Antibodies against myelin-oligodendrocyte-glycoprotein (MOG-Abs) associated disease (MOGAD) has been recognized as a disease entity. Optic neuritis (ON) is the most common symptom in MOGAD. To demonstrate the differences in retinal microvascular characteristics between patients with MOGAD-ON and aquaporin-4 antibody (AQP4-Ab) positive ON.In a prospective study, optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) were used to measure retinal and microvascular parameters.p < 0.001, respectively), but comparable to AQP4-ON eyes. The vessel density in retina capillary plexus (RCP) was reduced significantly in MOGAD-ON than that in AQP4-ON . The visual accuracy was positively correlated with vessel density of superficial RCP in MOG-ON (p = 0.001) and positively correlated with the thickness of the inner retina layer in AQP4-ON (p < 0.001).Twenty-six MOGAD-ON eyes, 40 AQP4-ON eyes, and 60 control eyes were included in the study. The thickness of RNFL and GCC in MOGAD-ON eyes was significantly lower than that of HC . Antibodies against myelin-oligodendrocyte-glycoprotein (MOG-Abs) have been detected in several autoimmune central nerve systems (CNS) disorders, in which the clinical characteristics often overlap with aquaporin-4 (AQP4) Ab-negative neuromyelitis optica spectrum disease (NMOSD) , 2. ReceBoth optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) are non-invasive imaging techniques used to visualize the microstructures of the fundus. OCT performs a real-time and in vivo retinal biopsy to directly visualize the microstructure of human eye tissue, including the peripapillary retinal nerve fiber layer (pRNFL) and ganglion cell complex (GCC) . The pRNWith the utilization of retinal OCT in clinical neuroimmunology, researchers successively observed that pRNFL and GCC were significantly thinning in NMOSD-ON , 15 and We performed a prospective study, Clinical and Imaging Patterns of Neuroinflammation Diseases in China . Patients with a history of ON were enrolled from Jan. 2019 to Jan. 2022 in the neurology department of Beijing Tiantan Hospital, Capital medical university. ON was defined as the presence of an acute relapse lasting more than 24 hours and associated with decreased high-contrast letter acuity, pain with eye movement, color desaturation and/or visual field (VF) abnormalities, with or without optic nerve swelling or enhancement visualized by magnetic resonance imaging (MRI). Ethical approval for this study was obtained from the Institutional Ethics Committee at Beijing Tiantan Hospital.The inclusion criteria for patients were as follows: (1) best-corrected visual acuity (BCVA) of the eye with better eyesight ≥20/400, intraocular pressure (IOP) ≤ 21.0 mmHg, a spherical equivalent less than 3.00 D; (2) the duration more than 6 months since last ON attack ; (3) serThe AQP4-IgG antibody and MOG-IgG antibody testing were performed blindly at the Euroimmun Medical Diagnostic Laboratory (China) using a fixed-cell-based indirect immunofluorescence test on BIOCHIPs . Information including demographic data, disease duration of ON, time since previous ON attack, ON relapse times and status of MOG-Abs and AQP4-Abs were collected and reviewed. The evaluation of EDSS was evaluated independently by two neurologists according to a predefined standard on the same day as the ophthalmoscopic examinations.Early Treatment Diabetic Retinopathy Study (ETDRS) charts  were used to collect the prognostic Best-Corrected Visual Acuity (BCVA) of the patients with ON. The presented letter-acuity scores may be converted to LogMAR (logarithm of the minimum angle of resolution) as follows: LogMAR = −(0.02) * Letters + 1.1 . Due to The thickness measurements of pRNFL, inner retina, and outer retina were performed with an RTVue-XR Avanti spectral-domain OCT . Retinal imaging was firstly performed by a three-dimensional (3D) reference scan, which was used as the reference and registration image for the enhanced macular map 5. It consisted of a dense grid scan in a 6 × 6 mm central macula area. The optic nerve head (ONH) scan consisted of 13 concentric rings with diameters ranging from 1.3–4.9 mm and 12 radial lines with 3.4 mm in length. The thickness of the retinal nerve fiber layer (RNFL) was measured at a diameter of 3.45 mm around the center of the disk using the ONH protocol. RNFL analysis was done in 8 sectors namely superotemporal (ST), superonasal (SN), inferotemporal (IT), inferonasal (IN), nasal inferior (NI), nasal superior (NS), temporal inferior (TI), and temporal superior (TS).The perifoveal retina was divided into the inner retina and outer retina. The perifoveal retina scan is 1 mm temporal from the foveal center, and consists of 15 vertical line scans, covering a 7 mm square area . The ganOCTA scans of the optic disc (4.5 * 4.5 mm) and macula (6 * 6 mm) were obtained by a spectral domain system . The radial peripapillary capillary network was visualized on scans within a 1.0 mm wide elliptical annular region extending outward from the optic disc boundary, and the vasculature within the internal limiting membrane and the nerve fiber layer were analyzed automatically using the software.p < 0.001). Poor-quality photographs with a signal strength index less than 40 or images with residual motion artifacts were rejected. In terms of the OCT and OCTA acquisition, we followed OSCAR-IB [The parafoveal capillary network was observed on scans of a circular area with a diameter of 1 mm–3 mm surrounding the fovea, while the scan of the 3 mm–6 mm annular area around the parafoveal capillaries was a perifoveal capillary network. Both parafoveal and perifoveal capillary networks were further divided into superior and inferior hemispheres, temporal section (TEM), nasal section (NAS), inferior section (INF) and superior section (SUP). The superficial retinal capillary plexus (SRCP) was analyzed from 3 mm below the internal limiting membrane to the outer boundary of the IPL, and the deep retinal capillary plexus (DRCP) was referred to the layer from IPL to ONL. Macular layer segmentation was automatically recognized by the software inside the machine . The vessel density was calculated as the percentage area occupied by the large vessels and micro-vessels in the analyzed region. They were automatically generated in the whole scan area and all sections using the software . Two experienced ophthalmologists blindly evaluated the quality of OCTA images to determine interobserver reproducibility , and GraphPad Prism version 7.0  were used to analyze and create graphs. Data were presented by n (%), mean (SD) or median (range). The t-test or Mann–Whitney test were used to compare demographic characteristics and clinical presentations. The chi-square test was used to compare the proportion of eyes with reduced RNFL in each quadrant. The generalized estimating equation (GEE) was used throughout the analysis whenever applicable for adjusting for age, gender, disease duration and the inter-eye correlation. Univariate and multivariate linear regression methods were used to analyze the effects of OCT and OCTA parameters on visual function. We considered outcomes with a p = 0.007). The average visual accuracy of patients with MOG-ON was statistically lower than that of AQP4-ON patients (p = 0.023).Seventeen MOGAD-ON (26 eyes), 26 AQP4-ON (40 eyes), and 30 HC (60 eyes) participants were included in the study. The demographic and clinical features of patients and healthy controls were presented in Table p < 0.0001 for all). Besides, the thickness of the inner retina (GCC) was significantly thinner in MOGAD-ON than in HC (p < 0.001).Detailed afferent visual system parameters analyzed by OCT and OCTA were respectively summarized and compared in Table p < 0.0001 for all, see Table As for the retinal vessel density between MOGAD-ON and HC, the average vessel densities of optic disk radial peripapillary capillaries (RPC) and retina in MOGAD-ON were significantly lower than that in HC , parafoveal vessel densities in the superior, nasal and inferior area , and perifoveal vessel densities in nasal and inferior area  were significantly decreased in the MOGAD-ON eyes than that in AQP4-ON eyes (Table As for the deep retina capillary plexus (DRCP), the whole vessel density , average pRNFL thickness (p = 0.037), average inner retina thickness (p = 0.034), and the average vessel density of superficial retina (p = 0.001). Above factors were selected for multivariate modeling. After adjustment by multivariable linear regression, the LogMAR was significantly correlated with vessel density of SRCP .In univariate analysis of parameters in MOGAD-ON, the LogMAR was significantly correlated with the duration since last ON (p = 0.004), average pRNFL thickness (p < 0.001), average inner retina thickness (p < 0.001), the average vessel density of superficial retina (p < 0.001) and average vessel density of deep retina (p = 0.005). Above factors were selected for multivariate modeling. The LogMAR was significantly related to the thickness of inner retina layer , rather than any retinal vessel density.As for AQP4-ON cases, in univariate analysis, the LogMAR was significantly related to the disease duration (In this study, we mainly demonstrated differences of retinal microstructure and vasculature between MOGAD-ON and AQP4-ON. MOGAD-ON eyes presented with severe thinning of RNFL, the extent and quadrant of which were comparable to eyes with AQP4-ON. The vessel densities of DRCP in the macular area of MOGAD-ON eyes were significantly lower than that of AQP4-ON eyes. Furthermore, the reduced microvascular densities were positively correlated with the deterioration of the visual acuity in MOGAD-ON.MOGAD has gradually been a separate disease entity from NMOSD as the distinct pathologies mediated by MOG-Abs. In previous studies, changes in the retinal structure in MOGAD and NMOSD eyes have been separately described , 27. ConHowever, OCT findings regarding comparing retinal microstructure changes between MOGAD-ON and AQP4-ON eyes have been inconclusive. Some studies have shown that compared with AQP4-Ab-positive NMOSD, MOGAD-ON led to less severe retinal damages , 29, butThe OCTA data regarding MOG-Ab-associated retinal vessel degeneration are scarce. In conformity with previous study , the micMOGAD-ON relatively preserved visual acuity compared with AQP4-ON, even if the severity of retinal damages was similar . Unlike The limitations of our study mainly included that the sample size was relatively small, which is expected given the rarity of these conditions. Whether the vascular changes precede the changes of retinal structure or are secondary to retinopathy cannot be proved. In addition, we didn’t include eyes that were positive for MOG-Ab and AQP4-Ab because “double positive” cases were sporadic.In conclusion, the retinal neuro-axonal damages in MOGAD-ON were comparable to AQP4-Abs-positive ON. Compared to AQP4-Abs, the MOG-Abs might be related to more severe vascular damage. And the reduced microvascular densities were positively correlated with the deterioration of the visual acuity in patients with MOGAD-ON. Here, we stressed the different pathophysiology between MOGAD-ON and AQP4-ON, but the mechanisms by which MOG-Abs destroys the retinal structure and function are still unclear.


Parkinson’s disease (PD) is associated with a progressive inability to accomplish essential activities of daily living (ADL) resulting in a loss of autonomy and quality of life. Accurate measurement of ADL in PD is important to monitor disease progression and optimize care. Despite its relevance, it is still unclear which measurement instruments are the most suitable for evaluating ADL in people with PD.To identify and critically appraise which measurement instruments have been used to assess ADL in PD.A systematic review was conducted using the databases CENTRAL, MEDLINE, and PEDro from their inception to October 2021 to identify all observational and experimental studies conducted in PD or atypical parkinsonism that included an ADL assessment. Titles and abstracts were screened independently by two authors. The clinimetric properties of the measurement instruments were assessed, and the instruments were classified as “recommended,” “suggested,” or “listed.”A total of 129 articles were included, with 37 measurement instruments used. The Unified Parkinson’s Disease Rating Scale (UPDRS), the Schwab & England ADL scale , the Movement Disorder Society Unified Parkinson’s Disease Rating Scale (MDS-UPDRS), the Barthel Index, the Lawton-Brody Instrumental Activities of Daily Living Scale, the Functional Independence Measure (FIM) and the Alzheimer’s Disease Cooperative Study – ADL (ADCS-ADL) scale were the seven most frequently cited measurement instruments. Of these, only two included an assessment of basic and instrumental ADL.MDS-UPDRS and the S&E scale were the only two scales that could be classified as recommended. For the MDS-UPDRS, either the full version or only Part II, which is focused on ADL, can be used. Future studies should explore the use of wearable devices to assess ADL remotely and more continuously. Parkinson’s disease (PD) is a heterogeneous neurodegenerative disease characterized by a wide range of motor and non-motor symptoms . RegardlThe term “Activities of Daily Living” (ADL) refers to the fundamental skills required for self-care, such as eating, bathing, and mobility . There aAs PD progresses, patients’ ability to perform ADL deteriorates . EvaluatWe searched CENTRAL, MEDLINE, and PEDro from their inception to October 2021 using the following keywords “Parkinson*,” “Activity* daily living,” and “ADL.” Reference lists from the identified articles were cross-checked to identify any further potentially eligible studies.Observational and experimental clinical studies conducted in PD and/or atypical parkinsonism were included. Studies had to include an ADL assessment and describe the measurement tool used. Studies written in languages other than English, Portuguese, and Spanish were excluded. Two authors independently screened abstracts obtained from the database search. The full texts of potentially relevant articles were retrieved for further assessment. Disagreements were resolved by consensus or by consultation with a third reviewer.The following data from the individual studies were included in a pre-piloted form: general information ; ADL measurement tools  and measurement instrument classification.Based on criteria used in previous reviews, measurement instruments were classified as recommended, suggested, or listed . These iThe search for studies evaluating the clinimetric properties of the included measurement tools was based on previous research  and the The primary outcome was to identify the measurement instruments currently used to evaluate ADL in people with PD. Descriptive data were summarized using frequencies and percentages.n = 2167), wrong study design (n = 973), and ineligible base population (n = 653) were the most common reasons for exclusion.The electronic searches identified 2,900 citations . A totaln = 40), prospective cohort  and randomized controlled studies . The median sample size was 64  patients, with a study duration ranging from one to 180 months. ADL was the primary outcome in 88.4% (n = 114) of the studies.Over time, the number of studies evaluating PD has increased . Of the n = 17) can be used as patient- or clinician-reported outcomes, 27.2% (n = 10) were clinician-reported outcomes (ClinRO), 16.2% (n = 6) observer-reported outcomes (ObsRO), and 8.1% (n = 3) were patient-reported outcomes (PRO). Wearable sensors were used in one of the studies to evaluate specific movements related to ADL   .The most frequently cited measurement instruments (used in at least five studies) are summarized in Regarding the Unified Parkinson’s Disease Rating Scale (UPDRS) and the Movement Disorder Society Unified Parkinson’s Disease Rating Scale (MDS-UPDRS), the included studies only used the section dedicated to ADL (Part II). We chose to present the scale in its entirety in this review, stating whether Part II can be used independently and what its benefits are.n = 44) of the included studies.Unified Parkinson’s Disease Rating Scale Part II was used in 34.1% . A lower score represents less disability in performing ADL in PD. According to its description, the average time required to administer the full scale is between 10 and 20 min  for the entire scale and substantial (ICC = 0.85) for the ADL section. It has adequate internal consistency  and inter-rater reliability (k ≥ 0.4), criterion, and convergent validity. The clinimetric properties for Part II as an independent scale were already studied and showed that floor and ceiling effects, convergent validity, reliability, and standard error of measurement, found to be adequate . Its main drawbacks are its reliance on the expertise of the evaluator and the amount of time it takes. Although it is estimated to take 10–20 min, due to the numerous topics that must be discussed with the patient, it may take longer, limiting its use in clinical practice. The Movement Disorder Society (MDS) sponsored a critique of the UPDRS in 2001, which praised the scale’s strengths while pointing out several ambiguities, flaws, and areas that needed to be included to reflect current scientific developments. In 2008, the MDS developed a new version of the scale, which addressed some of the original scale’s flaws and included several clinically relevant PD-related issues that were underrepresented in the original version. Although the new version of the scale was recommended, the transition was not immediate as the old version had been used in several studies after 2008 (ter 2008 .n = 30) of the included studies.Schwab and England Daily Living Activities Scale was used in 23.3%  to 100% (completely independent). This instrument takes about 5 min to administer . A 10-point change was reported as the minimum clinically significant difference  of the included studies.Movement Disorder Society-Unified Parkinson’s Disease Rating Scale Part II was used in 7.0%  and II have been designed to fit into a patient/caregiver questionnaire format, allowing them to be completed without the assistance of the investigator. All questions in Part I that deal with complex behaviors (items 1.1–1.6) and all questions in Part IV that deal with motor fluctuations and dyskinesias require the investigator to conduct the interview. Part III keeps the objective assessments of parkinsonism but has now more detailed instructions  and is highly correlated with the original UPDRS (q = 0.96). It also has an excellent construct validity (r = 0.92). The instrument has strong concurrent validity based on high correlations with the UPDRS , as well as between the individual parts of the two scales. According to r = 0.70–0.80) and quality of life scales , which proves useful for assessing disability in PD  of the included studies.The Barthel Index was used in 7.0% , mobility (on a level surface), and stairs (ascending and descending). It can take 5–20 min depending on how the assessment is performed (self-report vs. direct observation). Higher scores imply greater functional independence, with a severity cut-off of 0–20 indicating “complete” dependency, 21–60 indicating “severe” dependency, 61–90 indicating “moderate” dependency, and 91–99 indicating “slight” dependency , inter-rater/intra-rater reliability  and internal consistency . It also has moderate to high convergent validity in ON and OFF phases (ρ = 0.48–0.82) (48–0.82) .Feasibility: The Barthel Index is a straightforward tool that takes only a few minutes to complete and provides a global but comprehensive view of the patient’s ADL performance. It can be used in both the early and advanced stages of the disease because it can be used as a self-completion questionnaire or for direct observation. The rating system uses the numbers 0–unable, 1–requires assistance, and 2–independent, which does not allow for a detailed description of the difficulties in each task (ach task .n = 6) of the included studies.The Lawton-Brody scale was used in 4.7%  to 1 (can perform) based on their highest level of functioning. The total score ranges from 0  to 8 . The assessment takes about 10–15 min to complete . Its validity was tested by determining the correlation with four scales that measure domains of functional status: Physical Classification , Mental Status Questionnaire (10-point test of orientation and memory), Behavior and Adjustment rating scales , and the Physical Self-Maintenance Scale (6-item ADLs) and all the correlations were significant at the.01 or.05 levels. The scale has also been validated for people with dementia, showing a moderate internal consistency and excellent test-retest reliability  its use is not advised, due to the fact that the lack of responsiveness to some questions is due to cultural differences, not because of the inability to perform those tasks.n = 5) of the included studies.The Functional Independence Measure (FIM) was used in 3.9%  to 7 (complete independence) (endence) .Clinimetric properties: The clinimetric properties of the scale have not been assessed in the PD population. Studies in older adults have shown an excellent test-retest reliability (ICC = 0.98) and studies in neurological disorders (not specified which) showed excellent internal consistency  ( = 0.95) .Feasibility: The FIM provides realistic and detailed information about a patient’s level of self-care disability. It has the drawbacks of requiring training, being time-consuming (it takes 30–45 min to administer) and requiring environmental conditions that allow self-care tasks to be performed.n = 5) of the included studies.The Alzheimer’s Disease Cooperative Study – Activities of Daily Living Inventory (ADCS-ADL) was used in 3.9%  field. It includes 23 items, 6 basic ADL items, and 17 instrumental ADL items. The total score ranges from 0 to 78, with a lower score indicating greater severity  using it as the primary outcome. A total of 37 different measurement instruments were used. Of the eight most used measurement instruments, the majority focused on the assessment of basic ADL, with only three including both basic and instrumental ADL assessment.According to our results, two measurement instruments can be classified as recommended: the MDS-UPDRS and the Schwab & England ADL scale . In some of the included studies, these scales were combined. Only the MDS-UPDRS assesses basic and instrumental ADL.Regarding the MDS-UPDRS, both the full scale and the independent use of the section dedicated to ADL (Part II), proved to be useful in measuring ADL. The full scale can provide a more comprehensive perspective on how disease severity limits patients’ ability to perform ADL since, besides the patient questionnaire focused on ADL, it includes a motor assessment (a more objective measure) and a questionnaire about non-motor aspects and motor complications associated with PD. It also specifies if a patient was in an ON- or OFF-medication state. However, this is a time-consuming scale, for which the independent use of Part II can be, in some circumstances, a more feasible measurement instrument to evaluate ADL in PD patients.While the MDS-UPDRS Part II covers both specific basic and instrumental ADL and explores the difficulty presented by the patient in performing each task, the S&E scale provides a global perspective of the level of independence in performing tasks in general. This can be useful in circumstances where a quick and global perspective of a patient’s level of disability is needed.Although UPDRS complies with all the criteria required to achieve the level of “recommended” and was the most widely used scale for the clinical study of PD for several years, it was replaced by the MDS-UPDRS due to the need to correct some flaws and ambiguities present in the scale and include the evaluation of some relevant missing items. We propose that the MDS recommendation of using the revised version of the scale (the MDS-UPDRS) be followed in order to reduce the variability of the instruments used to assess ADL.Of the eight most used measurement instruments, only one, the Barthel Index, achieved the level of suggested. This is an instrument focused on basic ADL.The Barthel Index provides a more complete perspective of patients’ ability to perform ADL than the S&E scale, but a less detailed perspective when compared with the MDS-UPDRS Part II. This measurement instrument was not specifically developed for PD patients, therefore, it does not have a disease-specific perspective when assessing ADL. It is a scale that can be used to evaluate patients through observation but is most often used as a self-completion questionnaire, which can be completed by the patient or caregiver. It has the advantage of being a scale that is simple to use and capable of being filled in by third parties in cases of cognitive deficit (common in advanced stages of the disease). It has the disadvantage of only covering basic ADL and not instrumental ADL. Future studies should study the clinimetric properties of the scale in people with PD. It is a very useful and feasible non-disease-specific instrument to assess ADL for example in institutionalized patients or rehabilitation centers.Three of the eight most used measurement instruments were classified as listed: the Lawton-Brody scale, the FIM, and the ADCS-ADL. Clinimetric properties in the PD population are not available for any of these instruments. Only the ADCS-ADL assesses basic and instrumental ADL, the Lawton-Brody scale is the only instrument  that only assesses instrumental ADL.The Lawton-Brody scale has the added value of approaching instrumental ADL. However, it does not include the assessment of basic ADL and is only applicable in independent, non-institutionalized/hospitalized patients. Its use may be conditioned in some cultures where men do not perform certain tasks related to housekeeping . As PD is more common in men and is also a progressive disease, these factors may limit the use of the scale in clinical practice and research.The FIM addresses basic ADL by dividing them into motor  and cognitive . ADL can be assessed through observation or interview. Although it takes between 35 and 40 min to administer, it is a frequently used measurement instrument in health institutions for patients with different diagnoses, since it allows the monitoring of the patient’s evolution in response to both disease progression and therapeutic interventions, it is not limited to any stage of the disease and provides a multidisciplinary perspective.The use of the ADCS-ADL, an instrument developed for patients with AD and not validated in PD, may, at first glance come as a surprise. In our opinion, the fact that this instrument is one of the most used is related to the fact that it evaluates, in a detailed way, an extensive set of ADL, including basic and instrumental ADL. Excluding the MDS-UPDRS, the remaining instruments analyzed here only assess one type of ADL, and the MDS-UPDRS itself does not present such a complete assessment. For research purposes, the ADCS-ADL could be a useful instrument, if its clinimetric properties are studied in PD. Its use in clinical practice is limited by the time it takes to apply.One of the included studies used wearable sensors to evaluate ADL.The traditional measurement instruments, while accessible and useful, have certain limitations. These include: (1) only providing brief “snapshots” of a patient’s performance, with limited ability to capture how it fluctuates through the day and over time); (2) being subject to intra- and inter-rater variability; (3) requiring an in-person at the very least a telephone assessment; and (4) being time-consuming.To overcome the limitations of traditional clinical scales, a plethora of new and improved devices have been developed thanks to technological advancements. These have the added value of: (1) capturing the full complexity and diversity of PD symptoms with higher sensitivity and accuracy; (2) providing a more realistic portrayal of patients’ performance; and (3) enabling closer monitoring of therapy response. However, while technology-based objective measures (TOMs) are very promising, some aspects of them need to be improved. The main disadvantage is that, despite significant and rapid advancements in device characteristics, algorithm development has lagged. Currently, issues like algorithmically analyzing captured data, defining truly relevant clinical information, and displaying it synthetically and intuitively need to be addressed.Future research should explore the use of wearable sensors to monitor ADL in patients with PD, preferably in free-living and passively.From the eight most used measurement instruments, two are classified as recommended: the MDS-UPDRS and the S&E scale. The full MDS-UPDRS can provide a more comprehensive perspective of patients’ ability to perform ADL, however, it is time-consuming to use in clinical routine. To overcome this difficulty, the MDS-UPDRS Part II, which focuses on ADL and assesses it through a self-administered questionnaire, can be used as an independent measurement instrument. If a more global perspective of patients’ independence in performing ADLs is sought, the S&E scale is a better option. As the development of TOMs continues, we believe that they might become the best tool to assess ADL in a real, unsupervised context.The original contributions presented in this study are included in the article/supplementary material, further inquiries can be directed to the corresponding author.JF and RB-M contributed to the conception of the study. RB-M, CR, and DB conducted the literature search and study selection. AF and RB-M performed data extraction and data analysis and drafted the manuscript. All authors contributed to manuscript revision, read, and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Mendelian randomization (MR) uses genetic variants as instrumental variables to investigate the causal effect of a risk factor on an outcome. A collider is a variable influenced by two or more other variables. Naive calculation of MR estimates in strata of the population defined by a collider, such as a variable affected by the risk factor, can result in collider bias. We propose an approach that allows MR estimation in strata of the population while avoiding collider bias. This approach constructs a new variable, the residual collider, as the residual from regression of the collider on the genetic instrument, and then calculates causal estimates in strata defined by quantiles of the residual collider. Estimates stratified on the residual collider will typically have an equivalent interpretation to estimates stratified on the collider, but they are not subject to collider bias. We apply the approach in several simulation scenarios considering different characteristics of the collider variable and strengths of the instrument. We then apply the proposed approach to investigate the causal effect of smoking on bladder cancer in strata of the population defined by bodyweight. The new approach generated unbiased estimates in all the simulation settings. In the applied example, we observed a trend in the stratum-specific MR estimates at different bodyweight levels that suggested stronger effects of smoking on bladder cancer among individuals with lower bodyweight. The proposed approach can be used to perform MR studying heterogeneity among subgroups of the population while avoiding collider bias.The online version contains supplementary material available at 10.1007/s10654-022-00879-0. Mendelian randomization (MR) is the use of genetic variants as instrumental variables to assess the causal relationship between a risk factor and an outcome , 2. A vaCollider bias can occur when conditioning on a collider, defined as a variable that is a common effect of two or more variables –10. The Selection bias is a form of collider bias that occurs when selection of individuals into a dataset is dependent on a collider. For example, when disease progression is considered as an outcome, only patients who have already developed the disease would be recruited into the study . If riskCollider bias could also occur when stratifying the population based on a collider. As an example, we consider investigating the causal effect of the risk factor on the outcome for individuals with specific levels of a stratifying variable. Stratification is important for identifying whether there are subgroups of the population for which causal effects of the risk factor are different, and so the outcome would be affected more strongly by an intervention on the risk factor. However, if the stratifying variable is a collider, an association between the instrument and the outcome in strata of the population could arise due to collider bias, invalidating the results. In particular, collider bias could affect some estimates more than others, leading to heterogeneity in the stratum-specific causal estimates even if the true causal effect is the same across strata. Although several previous papers have considered collider bias arising due to differential selection into the study sample , 13, 16,The aim of this paper is to present an MR approach that obtains estimates in strata of the population that do not suffer from collider bias. The structure of this paper is as follows: first, we demonstrate the bias that arises from conditioning on a collider; second, we propose an approach to calculate MR estimates in strata of the population and evaluate heterogeneity between estimates in the different strata; third, we illustrate this new technique in simulation studies and an applied example using the UK Biobank resource; and finally, we discuss the interpretation of estimates and limitations of the approach.X on outcome Y with a genetic instrument G is the ratio method [Y on G, and X on G [G, X, and Y are available in the same individuals (known as “one-sample MR”), the same estimate with a single IV can be obtained using the two-stage-least-squares method.The simplest MR method to estimate the causal effect of a risk factor o method . With a entclass1pt{minimaC in the regression models for the ratio estimate, since an association between the instrument and the outcome will occur through conditioning on the collider. To demonstrate the impact and magnitude of collider bias, we performed a simulation study in which we compared estimates when no adjustment on C is made versus when the outcome regression is adjusted for C. It is also possible to adjust the risk factor regression for C; however, while this will distort estimates, this adjustment alone will not bias causal estimates when the true causal effect is null. Under the causal null, the genetic association with the outcome will tend towards zero, and so the expectation of the IV estimate will be zero even if the genetic association with the risk factor is misestimated.Collider bias will occur when adjusting for a collider variable M in the graph M in the graph M in the graph In Pearl’s language of d-separation (open and closed paths), conditions for a valid instrument are: 1) there must be an open pathway from the instrument to the exposure, and (2) all pathways between the instrument and outcome must be closed in a modified graph where all edges out of exposure are removed . A path collider . In this there muC, and second, we stratified on a new variable C0, referred to as the “residual collider”. The residual collider was generated as the residual from regression of the collider on the genetic instruments:To further illustrate the impact of collider bias, we performed a simulation study in which we calculated causal estimates using the ratio method within strata of the population defined using a variable that is influenced by the risk factor, and hence is a collider. We compared two approaches: first, we stratified directly on the collider C on G.C0 is not associated with the instrument, and hence it is not itself a collider. It is influenced by the component of the risk factor that is not a function of G (defined as X0), but not by the component that is a function of G, as shown in Fig. C0 does not lead to invalidity of the instrumental variable assumptions. Moreover, provided that the genetic instrument does not explain much of the variance in the risk factor , it is likely not to explain much of the variance in the collider, and so the residual collider will be highly correlated with the collider. Hence, while stratifying on the residual collider is important to avoid bias, the strata defined by stratifying on the collider or residual collider are likely to be similar and so any difference in the interpretation of stratum-specific estimates is minimal. If the genetic instrument explains a substantial portion of variance in the risk factor, then the residual collider will not be as highly correlated with the collider, and so differences in the strata explained by the residual collider and collider would be more substantial. Even so, stratum-specific estimates represent Mendelian randomization estimates in strata of the population with different average levels of the collider, which can be meaningfully compared.The residual collider Here we considered estimates in four strata of the population defined by quartiles of the distribution of the collider or residual collider; however, in practice any number of strata could be considered. We estimated genetic associations with the outcome in each stratum separately. We estimated genetic associations with the risk factor in the full dataset, although if it is believed that these associations vary between strata, it would be possible to estimate these within each stratum as well. The stratum-specific estimate is calculated as the ratio of the stratum-specific genetic association with the outcome divided by the genetic association with the risk factor. The interpretation of stratum-specific estimates is equivalent to that of IV estimates obtained in the whole population; depending on the version of the IV4 assumption, they either target an average or a local average causal effect , and  X and Y , and self-reported information from an interview with a nurse practitioner. The instrument for smoking was a weighted genetic risk score comprising 378 conditionally independent SNPs obtained from a genome-wide association study (GWAS) assessing associations with smoking initiation , and weighted by the associations with smoking initiation [We performed analyses in the UK Biobank study, a population-based cohort of more than 500,000 United Kingdom residents recruited between 2006 and 2010 . For ouritiation . Geneticitiation .2 = 0.006 for the mean proportion of variance in the risk factor explained by the instrument and a mean F statistic of 60.8) and Supplementary Tables 1 and 2 for 2 = 0.051, mean F statistic of 548.6) and 2 = 0.001, mean F statistic of 15.3). In each case, we report the median estimate of Y on G, estimates were biased, and type I error rates were substantially above 5%. The only exception was for C is not a function of the risk factor, and so does not act as a collider. Bias and type I error rates generally increased for more extreme values of Results from Scenario A1  are presented in Table In Scenarios B1 , there was evidence of trend in the stratum-specific estimates for residual bodyweight from meta-regression on the mean value of bodyweight in each stratum . These results suggest that the effect of smoking on bladder cancer is stronger for subgroups of the population with lower bodyweight.Estimates for the causal effect of smoking on bladder cancer in strata of bodyweight and residual bodyweight are shown in Table In this paper, we have demonstrated that conditioning or stratifying on a variable that is a collider can have a serious impact on MR estimates. We have introduced a simple approach that constructs a new variable, the residual collider, which is typically highly correlated with the collider, but is independent of the instrument. Estimates obtained from stratification on the residual collider did not suffer from bias in a range of simulation studies. Stratification on the residual collider allows investigators to explore causal estimation in relevant subgroups of the population. We applied our new approach to demonstrate that MR estimates for the effect of smoking on bladder cancer differ within strata of bodyweight, suggesting that the effect of smoking is stronger for subgroups of the population with lower bodyweight.The approach of stratifying on the residual collider follows the same logic as a previously proposed method for non-linear MR, in which causal estimates are obtained in strata of the population defined by the “residual risk factor” or “IV-free exposure” , 30. ThiThere are some limitations to this approach. First, while the independence of the residual collider from the instrument is theoretically justified, we demonstrated the validity of our approach through simulation studies. Although we considered a range of different scenarios and parameter values, it is not possible to consider every possible data-generating mechanism by which that a collider could arise. Second, in practice, the relationships between variables are unknown, and so it may be unclear whether a proposed stratifying variable is a collider. However, even if the variable is not a collider, it is unlikely stratification on the residual variable will lead to invalid estimates, suggesting that this approach would be valid for stratifying on variables that are not colliders. This was demonstrated in the simulation study when the effect of the risk factor on the “collider” was zero Below is the link to the electronic supplementary material.


Introduction: Previous publications have suggested a link between decreased bone mineral density (BMD) and audiovestibular symptoms. Being the first study, to our knowledge, in the Caribbean region, we aimed to determine the relationship between hearing impairment, vertigo, and tinnitus with BMD in a Dominican postmenopausal population diagnosed with osteoporosis.Methods: A retrospective, cross-sectional, single-center study was conducted. Patients were enrolled using a previous database of Dominican postmenopausal women from 2008 to 2015, including a total of 101 participants. Patients were questioned for hearing difficulty, tinnitus, and vertigo. Body mass index (BMI), Bone Mineral Density (BMD) using T-scores, FRAX score, serum levels of 25-(OH) vitamin D, corrected calcium, phosphate, albumin, alkaline phosphatase, and smoking history were assessed. Statistical analysis was conducted using Chi-square, Mann-Whitney U test, and Odds Ratio.Results: Median age was 74 years with an interquartile range (IQR) of 12. Fifty-six patients had osteoporosis and 42 osteopenia. Women with osteoporosis diagnosed using a femoral neck T-score demonstrated a greater level of association as well as higher odds of developing vertigo and hearing difficulty than those diagnosed using a hip T-score.Conclusion: Special attention to the otologic evaluation of these patients as well as increasing the referral to a specialized consult is suggested. Additional multicenter prospective national studies are needed. Presbycusis, or age-related hearing loss, is a common affliction of the elderly. It typically begins around the age of 60, but certain stressors have been shown to accelerate its rate of decline. Initially believed to be associated with degenerative changes in the peripheral auditory system and plasticity in central neural processing, presbycusis is now recognized as a complex condition involving genetic predisposition, anatomical changes, noise exposure, hormones, ototoxic medications, head trauma, ear-related conditions, and some systemic diseases -4. PreviThe World Health Organization (WHO) predicts that by 2025, almost 500 million people aged 60 and older will have substantial age-related hearing loss . Its impOsteoporosis is a systemic skeletal disease characterized by low bone mass and microarchitecture deterioration of bone tissue, resulting in increased fracture risk . It is aThis has drawn our attention towards the development of strategies that could directly impact the improvement of quality of life among these patients. Being the first study, to our knowledge, in the Caribbean region to evaluate this relation, we aimed to determine the association between audiovestibular symptoms and osteoporosis in a postmenopausal population and assess the odds of developing these symptoms in patients with osteoporosis.A retrospective, cross-sectional, single-center study was conducted. Patients were enrolled using a previous database, from 2008 to 2015, in which Dominican postmenopausal women were thoroughly examined, including their audiological and vestibular sphere. The current study enrolled a total of 101 participants. Patients were divided into three groups, women with a history of vertigo, women with a history of hearing difficulty, and women with a history of tinnitus. Audiovestibular symptoms were assessed using self-reported qualitative data. Patients were questioned for hearing difficulty, tinnitus, and vertigo, as well as if they had a history of recurrent otitis media, impacted cerumen, Menier's disease, otosclerosis, a previous tympanoplasty, cochlear implant, myringotomy, and family history of hearing impairment. In addition, their smoking history was assessed.Body mass index (BMI) was calculated by dividing weight by the square of height (kg/m²). The femoral neck and total hip bone mineral density (g/cm²) were measured using bone density scans (DXA). The T-score is defined as the difference between a measured bone density and the expected young normal value divided by the population standard deviation (SD) derived from manufacturer-supplied guidelines. The WHO T-score criteria were used to diagnose osteopenia or osteoporosis; T-score ≥ 1 was considered normal; T-score < -1 was considered low bone mass (osteopenia); and T-score ≤ -2.5 osteoporosis . The FraStatistical analyses were performed using JASP version 0.13.1 for Mac, data were tabulated in spreadsheets. The Chi-square test was used to calculate the association between categorical variables as well as Phi to determine the level of association. Two group comparisons were made using the Mann-Whitney U test to assess whether the distribution of ranks was statistically significant. Odds ratio (OR) was used to determine the strength of association between bone mass and audiovestibular impairment symptoms, p-values < 0.05 were regarded as statistically significant.Out of the 101 patients , 56 were diagnosed with osteoporosis and 42 with osteopenia. No patient referred history of cerumen impaction, Meniere's Disease, myringoplasty, myringotomy, tympanoplasty, otosclerosis, or recurrent otitis media. Eight out of 11 patients with a family history of hearing loss were diagnosed with osteoporosis. One patient had cochlear implant history. Serum 25-(OH) vitamin D, corrected calcium, phosphate, albumin, and alkaline phosphatase demonstrated no significant difference between the means of any of the three groups Table . Women wWomen with osteoporosis diagnosed using the femoral neck T-score demonstrated a greater level of association as well as higher odds of developing both vertigo and hearing difficulty than those diagnosed using the hip T-score. Women with a history of tinnitus had a statistically significant association with osteoporosis diagnosed using the femoral neck T-score Table .Due to inconsistencies in previous research, we decided to conduct the first nationwide study to investigate the relationship between bone mineral density and audiovestibular symptoms. We found, as well as other publications ,4,8-9, aPresbycusis has been described to begin around the age of 60 as a symmetrical, slowly developing, high-frequency sensorineural hearing loss (SNHL) . IdentifNumerous studies on self-reported hearing loss have been conducted, where contradictory results have been identified. However, it has been proven to be strongly predictable at higher frequencies (4 to 8 kHz) hearing loss and in individuals aged 60 or older -13. For As mentioned in earlier research ,14, we dAs BMD of the femoral neck revealed a stronger association and OR with audiovestibular symptoms than the hip BMD, it's suggested that the femoral neck T-score could work as a more powerful predictor of hearing loss and vertigo development within these patients. This has been postulated in the past as a relation between the measured bone mass of the femoral neck and the petrous temporal bone because both contain a greater proportion of trabecular bone . It has The present study must be viewed in light of its limitations. Hearing impairment outcomes were just determined by the use of a self-reported setting, for which it may not apply to other circumstances or populations. Our findings suggest that reduced BMD may be a risk factor for hearing impairment in postmenopausal women; therefore, it is essential to accurately identify osteoporotic patients with hearing loss and provide them with the proper follow-up.This study found a strong association between audiovestibular symptoms and osteoporosis in postmenopausal women. Therefore, we suggest paying special attention to the otologic evaluation of these patients, as well as increasing the referral to a specialized consult. Additional multicenter prospective national and regional studies are needed to complement these findings and better understand the specific patterns of audiovestibular disorders among these patients.


Pulses are a group of leguminous crops that are harvested solely for their dry seeds. As the demand for plant-based proteins grows, pulses are becoming important food crops worldwide. In addition to being a rich source of nutrients, pulses also contain saponins that are traditionally considered anti-nutrients, and impart bitterness and astringency. Saponins are plant secondary metabolites with great structural and functional diversity. Given their diverse functional properties and biological activities, both undesirable and beneficial, saponins have received growing attention. It can be expected that redirecting metabolic fluxes to control the saponin levels and produce desired saponins would be an effective approach to improve the nutritional and sensory quality of the pulses. However, little effort has been made toward understanding saponin biosynthesis in pulses, and, thus there exist sizable knowledge gaps regarding its pathway and regulatory network. In this paper, we summarize the research progress made on saponin biosynthesis in pulses. Additionally, phylogenetic relationships of putative biosynthetic enzymes among multiple pulse species provide a glimpse of the evolutionary routes and functional diversification of saponin biosynthetic enzymes. The review will help us to advance our understanding of saponin biosynthesis and aid in the development of molecular and biotechnological tools for the systematic optimization of metabolic fluxes, in order to produce the desired saponins in pulses. Pulses are leguminous crops that are harvested strictly for their dry seeds, including peas, dry beans, lentils, chickpeas, faba beans, cow peas and pigeon peas. They are consumed worldwide, and have received growing attention due to both nutritional and environmental benefits. Pulses provide a rich source of protein, fiber, minerals and vitamins, as well as a healthy diet of low glycemic index that is also cholesterol-free and gluten-free. Pulses also contain an array of phytochemicals with various potential benefits for human health . SaponinSaponins are a structurally diverse group of specialized plant terpenoids in many plant species, consisting of either steroidal or terpenoidal aglycones linked to oligosaccharide moieties ,4. In diIt is generally believed that saponins contribute to the bitter and astringent taste of pulse-based food products . UnderstAphanomyces euteiches, or Rhizoctonia solani and Fusarium oxysporum) significantly increased the saponin content in grains of two pea (Pisum sativum L.) cultivars, Crécerelle and Firenza [Saponins display a wide range of biological activities such as anti-microbial or anti-insect repellent activity, being produced as plant defense molecules in response to biotic threats, pathogens and herbivores . Being a Firenza . Additio Firenza . Given t Firenza . In addi Firenza ,13,14,15In the context of human health, saponins exhibit a wide spectrum of pharmacological properties, including anti-cholesterolemic, anti-cancer and hemolytic activities ,4,9,16. Glycine max), peas (Pisum sativum) and chickpeas (Cicer arietinum) [Lens culinaris Medik.), chickpea (Cicer arietinum L.), faba bean (Vicia faba) and dry bean (Phaseolus vulgaris L.) [Soyasaponins, belonging to the oleanane triterpenoid group, are composed of soyasapogenol and oligosaccharide moieties, and are abundantly present in in the seeds of legumes such as soybean and pulses ,9. Four ietinum) . The conietinum) . Likewisietinum) . Howeverietinum) . One posaris L.) . Both graris L.) . Seed siaris L.) .Processing and cooking reduce the total saponins, although to various degrees, in different pulse grains ,31 and aIn this review, we will focus on the biosynthesis of triterpenoid saponins, since they are the class present in the pulses. Saponin biosynthesis involves sequential actions of three key classes of enzymes encoded by multi-gene families . The bioMedicago truncatula and in soybeans, only a few genes have been cloned and characterized in pulse crops (Although significant progress has been made on saponin biosynthesis in the model legume se crops . Many geP. sativum) OSC sequences reported by Vernoud et al. [M. truncatula, soybean (G. max) and pulse crops, including the common bean (Phaseolus vulgaris L.), tepary bean (Phaseolus acutifolis A. Gray), lima bean (Phaseolus lunatus), cowpea , lentil (Lens culinaris Medik.) and chickpea (C. arietinum) , cycloartenol synthase (CAS), lanosterol synthase (LAS), lupeol synthase (LUP) and several mixed-function OSCs that produce diverse products. These OSCs have specialized functions and make different major products . A neighd et al. , togetheietinum) . These Ouncatula  and Barbvulgaris , suggestvulgaris .bas1, in two different genetic backgrounds led to the identification of the PsBAS1 gene (Psat7g264880) encoding a β-amyrin synthase that was expressed in several tissues, including the developing seeds [PsBAS1 was much higher in the seed embryo than the seed coat, which coincided with the accumulation patterns of both DDMP and type B saponins. The expression of PsBAS1 was first detected at 19 days after pollination (dap) and increased as the seed matured with the peak at 29 dap [PsBAS1 throughout the pea seed development was in agreement with the accumulation pattern of saponin content, which was strongly increased in the late stage, indicating a key role of PsBAS1 in the biosynthesis of saponin [P. sativum, with one encoding β-amyrin synthase (PSY) [Psat7g264880, and the other encoding mixed amyrin synthase (PSX) to produce both α- and β-amyrin [Psat4g188800 at the amino acid level. A cDNA encoding cycloartenol synthase was isolated from pea seedlings [Psat1g051480. To our knowledge, OSCs have not been characterized in other pulse crops. Functional characterization of these OSCs is necessary to advance our knowledge of saponin biosynthesis and to facilitate the development of molecular tools to modify saponin content in pulse crops.A few OSCs have been isolated and functionally characterized in peas. Characterization of two ethyl methanesulfonate (EMS)-induced pea mutants, ng seeds . The expt 29 dap . The gen saponin . Two trise (PSY)  that wasβ-amyrin , which heedlings , with 99Leguminosae family, and have yet to be found outside the Leguminosae. Unlike CYP93E, the CYP72A subfamily is distributed across the entire plant kingdom [The second diversifying step for triterpenoid biosynthesis occurs when P450s catalyze the site-specific oxidation of the cyclized skeleton, primarily through the introduction of hydroxyl, carboxyl or epoxy groups . A largeP. sativum, M. truncatula, L. culinaris Medik. and C. arietinum L. are clustered together, suggesting that these species likely share a common ancestry. The CYP93E subfamily catalyzes the C-24 oxidation of the triterpene backbone (β-Amyrin) to produce 24-OH-β-amyrin during the biosynthesis of triterpenoid saponins [M. truncatula) and CYP93E8 (P. sativum) were demonstrated in a heterologous host (Saccharomyces cerevisiae) [M. truncatula ortholog CYP72A61v2 transform 24-OH-β-amyrin into the major soyasaponin aglycone, soyasapogenol B, by catalyzing the hydroxylation at the C-22 position [G. max) [Glyma15g39090 encoding the cytochrome P450 enzyme, CYP72A69, led to metabolic switching from undesirable group A saponins to beneficial DDMP saponins in soybean [Phylogenetic analysis of putative P450s involved in soyasaponin biosynthesis distinguishes three distinctive clades . Only a saponins . Differeevisiae) . The CYPposition . Soyasap[G. max) ,52,53. S soybean . The ideM. truncatula) can glycosylate certain isoflavones and the flavonol quercetin, in addition to triterpenoids [M. truncatula, UGT73K1 was demonstrated to have specificity for hederagenin and soyasapogenols B and E, while UGT71G1 has specificity for medicagenic acid [Glycosylation is the last modification step in the biosynthesis of saponins. This sugar conjugation step is important for the biological activities and chemical properties of saponins by regulating triterpenoid aglycones, including increasing their stability, water solubility and cell compartmentalization . The glyrpenoids . Most ofrpenoids . In M. tnic acid . In soybnic acid . The varnic acid .P. sativum, M. truncatula, L. culinaris Medik. and C. arietinum L. are clustered together. Multiple members are present in each of the subfamilies. However, further experimental studies are required to confirm whether they are involved in saponin biosynthesis, as well as what their functional mechanism is. It is not completely clear which enzymes are involved in the biosynthesis of DDMP soyasaponins. However, a member of UGT73B4, encoded by the gene Glyma.16G033700 in soybeans, has been suggested to function as a DDMP transferase, catalyzing the production of DDMP saponins from group B saponins [A neighbor-joining phylogenetic tree for the subfamilies of putative UGT71, UGT73 and UGT91 orthologs in pulse crops  shows thsaponins  and/or asaponins .Panax quinquefolius L) [M. truncatula, two JA-inducible bHLH TFs, TRITERPENE SAPONIN BIOSYNTHESIS ACTIVATING REGULATOR1 (TSAR1) and TSAR2 positively regulate non-hemolytic and hemolytic triterpenoid saponin biosynthesis, respectively [Medtr2g104650, regulates the expression of CYP88A13 in the developing seeds of M. truncatula, a cytochrome P450 that catalyzes the final oxidation step of the hemolytic saponin biosynthesis branch [M. truncatula by suppressing the activities of TSAR1 and TSAR2 [The biosynthesis and accumulation of saponin are subjected to the transcriptional, developmental and spatiotemporal modulation . Prior solius L) . In the ectively . A seed-s branch . Althougs branch . Comparend TSAR2 .Gleditsia sinensis Lam. (Leguminosae) [In addition to TFs, microRNAs (miRNAs) have been reported to be involved in terpenoid biosynthesis and accumulation in plants . The miRminosae) . HoweverQuillaja brasiliensis when exposed to abiotic elicitors such as salicylic acid, jasmonic acid, UV light and mechanical damage [The dynamic accumulation of secondary metabolites, including saponins, in response to environmental stimuli is an adaptive strategy of the plants which allows them to survive under adverse environmental conditions. Abiotic environmental factors, such as temperature and precipitation, affect the accumulation patterns of saponins, including their content and composition . Increasl damage . Furtherl damage . With inTriterpenoid saponin biosynthesis in pulses is poorly understood, and many pathway genes remain uncharacterized. Rapid advances in next generation sequencing technology promote the increasing availability of genome and pan-genome sequences of multiple crop species, which no doubt accelerates the discovery of new genes/alleles involved in saponin biosynthesis. Integrated applications of the genome, transcriptome, proteome and metabolome are opening up unprecedented opportunities for functional genomics to elucidate the molecular mechanism underlying triterpenoid saponin metabolism in pulse crops. In conjunction with exploiting natural gene variants in diverse germplasms, genetic engineering with CRISPR and/or molecular breeding for targeted production of saponins will facilitate the development of the varieties with balanced benefits to plant health, nutritional quality for human and animal consumption, and palatability for pulse food products.


The Alzheimer's Disease Cooperative Study – Activities of Daily Living Scale for use in Mild Cognitive Impairment (MCI), the ADCS-ADL-MCI, is an evaluation scale with information provided by an informant/caregiver to describe the functional impairment of patients with MCI. As the ADCS-ADL-MCI has yet to undergo a full psychometric evaluation, this study aimed to evaluate the measurement properties of the ADCS-ADL-MCI in subjects with amnestic MCI.Measurement properties, including item-level analysis, internal consistency reliability, test–retest reliability, construct validity , and responsiveness were evaluated using data from the ADCS ADC-008 trial, a 36-month, multicenter, placebo-controlled study in 769 subjects with amnestic MCI . Due to most subjects' mild condition at baseline and resulting low variance in scores, psychometric properties were assessed using both baseline and 36-month data.Ceiling effects were not apparent at the total score level, with 3% of the cohort reaching the maximum score of 53, despite most subjects having a relatively high score at baseline (mean score = 46.0 [standard deviation = 4.8]). Item-total correlations were overall weak at baseline, most likely due to low variability in responses; however, at month 36, good item homogeneity was found. Cronbach's alpha values ranged from acceptable (0.64 at baseline) to good (0.87 at month 36), indicating overall very good internal consistency reliability. Further, moderate to good test–retest reliability was found (intraclass correlation coefficients ranging from 0.62–0.73). The analyses also largely supported convergent/discriminant validity, especially at month 36. Finally, the ADCS-ADL-MCI discriminated well between groups showing good known-groups validity, and was responsive in patients who indicated a longitudinal change in other instruments.This study provides a comprehensive psychometric evaluation of the ADCS-ADL-MCI. Findings suggest that the ADCS-ADL-MCI is a reliable, valid and responsive measure capable of capturing functional abilities in patients with amnestic MCI.ClinicalTrials.gov Identifier: NCT00000173.The online version contains supplementary material available at 10.1186/s12877-022-03527-0. Mild cognitive impairement (MCI) is a common disorder in older populations with its prevalence increasing with age, as demonstrated by the findings that an estimated 6.7% of persons age 60–64 and 25% of persons age 80–84 are living with MCI globally . While MThe current view of AD is that the disease process and clinical manifestations are distributed along a continuum of decline, with symptoms reflecting mild cognitive impairment (MCI) occurring between "normal aging" and dementia . MCI canGiven the array of cognitive and functional impairments observed across the AD continuum, selecting suitable clinical outcome assessment (COA) instruments for measuring the effects of treatments in clinical trials with early symptomatic patients requires careful consideration. As AD patients may have a reduced ability to understand the impact of their disease on daily functioning, even early in the disease course , caregivThe Alzheimer's Disease Cooperative Study – Activities of Daily Living Scale for use in Mild Cognitive Impairment (ADCS-ADL-MCI) is a functional evaluation scale with the information provided by an informant/caregiver to describe the performance of patients in several ADLs. This measure is commonly used in clinical trials and clinical practice to measure the functional evolution of patients with MCI –15. HoweIn light of the evidence gaps regarding the measurement properties of the ADCS-ADL-MCI, the present study focused on the assessment of the psychometric properties of this instrument in subjects with amnestic MCI, including item-level analyses, internal consistency reliability, and homogeneity, test–retest reliability, construct validity , and responsiveness/sensitivity to change, using data from a large randomised controlled trial.n = 259); Vitamin E  plus a multivitamin daily (n = 257); or donepezil (10 mg) plus a multivitamin daily (n = 253). The primary outcome was the development of possible or probable AD dementia.The psychometric evaluation of the ADCS-ADL-MCI was undertaken using data from the ADCS ADC-008 trial, a 36-month, multicenter, randomized, double-blind, parallel-group, placebo-controlled study in subjects with amnestic MCI . All subN = 769). Further details of this trial are reported elsewhere [The science of evaluating an instrument’s measurement properties does not consider the biological mechanism of the underlying disease process and is agnostic as to the reasons why patients are in the evaluated disease state. As such, disease experiences as viewed through clinical measures and patient-reported outcomes resulting from treatment are considered equally usable to non-treated natural history patients . The psychometric evaluation of the ADCS-ADL-MCI was thus performed on all randomized subjects in the ADC-008 dataset for whom the ADCS-ADL-MCI was measured  through a structured questionnaire administered to the informant/carer by a physician or qualified rater . The ADCAPOE ε4 allele carrier status was assessed at screening only.To be able to assess the range of psychometric properties of the ADCS-ADL-MCI as detailed further below, several additional COA questionnaires were used that had been completed by patients, their caregivers, or clinicians at various time points. These questionnaires included the Global Deterioration Scale (GDS), the Informant Beck Depression Inventory (BDI), the NYU Delayed Paragraph Recall Test, and the Symbol Digit Modalities Test. Further, the Clinical Dementia Rating – Sum of Boxes (CDR-SB), the 11-item Alzheimer's Disease Assessment Scale – Cognitive Subscale (ADAS-Cog), and the Mini-Mental-State Examination (MMSE) were collected at screening and months 6, 12, 18, 24, and 36, while the Quality of Life – Alzheimer's Disease (QoL-AD) was assessed at baseline and months 6, 12, 24, and 36. Finally, the Mild Cognitive Impairment – Clinician Global Impression of Change (MCI-CGIC) was assessed at months 6 and 12, while Analyses were performed in accordance with a pre-specified statistical analysis plan (SAP). For the majority of the psychometric properties tested, screening/baseline and month 36 data were primarily used in the analyses; test–retest leveraged data from screening/baseline and month 6; responsiveness to change leveraged data from screening/baseline and month 36.The initial focus of the psychometric tests was baseline data, except for those tests that typically include follow-up data, such as test–retest or responsiveness analyses. However, initial analyses showed that the MCI population had limited functional impairments at baseline as reflected by low variability of the data and various ADCS-ADL-MCI items exhibiting ceiling effects. Further, some of the reference COA instruments were assessed at screening only , while the ADCS-ADL-MCI was assessed at baseline. Per protocol, the baseline was assessed between three and five weeks after the screening visit. While it is not expected that change occurred between these two assessments, ideally, data are evaluated on the same day to ensure that analyses, such as correlation analyses, are not affected by potential alternative effects such as different assessment time points. Therefore, for these two reasons the 36-month data were additionally included for all psychometric tests where applicable  and the fact that all COAs were assessed at the same time point). While evaluation of only placebo patients at month 36 was considered, the richness and real-world relevance of information contained in the full population was deemed more informative. Indeed, a heterogeneous cohort of patients was envisioned, with varying degrees of disease progression, which was considered helpful to evaluate the measurement properties. It is noted that patients at the 36-month timepoint do not include those who had progressed to dementia, and thus the sample only reflects those with slower disease progression.Item-level analyses  were evaluated using baseline and 36-month data, and items were further explored by sex, given the potential for certain items to differ by sex based on content. The item-level analyses included measures of central tendency , use of response categories for each item , and an assessment of floor and ceiling effects at the item-level  and total score-level .Internal consistency reliability  was assessed at baseline and month 36 using item-total correlations, with a target significant correlation > 0.30 indicating good homogeneity , 25, andTest–retest reliability  was assessed between baseline and month 6 (given the study design) among stable patients. Stability was defined in two ways: patients with no change in each of a) MCI-CGIC, GDS, and CDR-SB; or alternatively b) MCI-CGIC, GDS, and MMSE. As test–retest reliability is typically assessed across shorter time periods where there can be a strong rationale for disease stability , we sought assurance that the disease was stable. Therefore a three-component definition was employed using 1) a disease-specific assessment of global disease severity (MCI-CGIC), 2) a non-disease-specific global measure of disease severity (GDS) and 3) a detailed measure of disease severity (CDR-SB or MMSE). We examined both the CDR-SB and MMSE as we proposed the CDR-SB to be the more accurate measure of disease severity and the MMSE to be a measure with more widespread use (but higher variability in the MCI population). Mean differences and paired t-tests were calculated to compare ADCS-ADL-MCI total scores  between the two assessment visits. To assess test–retest reliability, the intraclass correlation coefficients (ICC) was computed where ≥ 0.7 indicates good reproducibility , 28.Convergent/discriminant validity ) was assessed using screening/baseline data by examining correlations of the ADCS-ADL-MCI with various COA measures included in the trial. Specifically, the ADCS-ADL-MCI was anticipated to be at least moderately correlated > 0.30) , 30 with , 30 witAPOE ε4 allele carrier status (carrier/non-carrier); 2) GDS categories ; 3) MMSE categories (< 27 vs. ≥ 27); 4) MMSE quintiles; 5) BDI categories ; 6) BDI quintiles; 7) CDR-SB categories (< 2.5 vs. ≥ 2.5); and 8) CDR-SB quintiles. Analysis of variance (ANOVA) models were used to assess differences in ADCS-ADL-MCI scores by severity groups, respectively.Known-groups validity  was examined at baseline (and at month 36 for consistency with the other psychometric tests) to determine whether the ADCS-ADL-MCI could distinguish between patients by disease severity within the MCI spectrum. Thereby, disease severity was defined in several ways: 1) Finally, responsiveness  was assessed using specific anchor measures to define groups of patients showing a change from baseline to month 36 based on the anchor measures. Specifically, patients were classified as 'improved,' 'no change,' and 'worsened' based on their change scores on 1) GDS; 2) CDR-SB; 3) global CDR, and 4) CDR-SB functional domain score. For example, patients who had a ≥ -1 point decrease on the GDS between baseline and month 36 were classified as 'improved.' Patients who had a ≥ 1 point increase on the GDS between baseline and month 36 were classified as 'worsened.' Stable patients were defined as those who did not experience any change in their condition according to the GDS between baseline and month 36 .Mean change between baseline and month 36 and effect size (ES)  were calculated for the ADCS-ADL-MCI total score within each change category, and effect sizes were compared . ANOVA wTo explore the dimensionality of the ADCS-ADL-MCI, both exploratory and confirmatory factor models were run. However, the models generally did not converge which is likely due to the low variance at baseline. In addition, the gating response format adds further complexity to running such models. Therefore, as results from the factor analyses were inconclusive, these are not reported in the results section.p < 0.05 was considered significant.SAS version 9.4  was used for all statistical analyses detailed above. In all of the analyses, APOE ε4 allele carriers (55%). The average age was 73 years (SD = 7.3). The mean number of years of education was 15 years (SD = 3.1), while the mean number of years since symptom onset was three years (SD = 2.6).The baseline characteristics of subjects with MCI included in the ADC-008 sample are presented in Table N = 265) of the cohort were APOE4 carriers.At baseline, the mean ADCS-ADL-MCI score was 46 (SD = 4.8), and most patients (57%) had mild cognitive decline defined by categories of GDS. The mean scores for the MMSE, CDR-SB, and ADAS-Cog at screening were 27.27 (SD = 1.9), 1.82 (SD = 0.8), and 11.28 (SD = 4.4), respectively. Scores on the other reference measures assessed in the trial are presented in Table Item-level analyses and the distribution of ADCS-ADL-MCI total scores for the full sample and by sex at baseline and month 36 are shown in Supplemental Tables At baseline, about two-thirds of individual items exhibited ceiling effects, i.e., a generally high level of ability of most patients regarding ADLs. Specifically, items 1, 2, 3, 10, 11, 12a-c, 13a, 14a, 15a-b, 16a-c, 17a, and 18a had strong ceiling effects, with over 80% of subjects being assessed as carrying out the respective activity "without supervision". Likewise, at month 36, most of these ceiling effects at the item level remained but to a lesser extent . Further, some differences were observed by sex for specific items, such that a lower proportion of males were endorsed in the first step of the gating question. This finding applied to items assessing cleaning or loading laundry; for example, 67% of males versus 88% of females were evaluated as having cleaned (item 4), and 45% of males versus 96% of females were assessed as having loaded laundry (item 7) in the past four weeks. Similar differences by sex were observed at month 36.At the total ADCS-ADL-MCI score level, the observed ceiling effects at baseline and month 36 were no longer apparent. With a maximum possible total score of 53, less than 3% of patients reached the top score, while less than 15% reached one of the top three scores at baseline . The overall distribution of scores at baseline was mean  = 45.95 (4.77) and median  = 47 (44–49.5). Similarly, less than 1% of patients reached the top score, and less than 13% reached one of the top three scores at month 36 . The overall distribution of scores at month 36 was mean (SD) = 40.63 (10.97) and median (IQR) = 45 .At baseline, most items in the ADCS-ADL-MCI did not correlate well with the total score of the remaining items . Four of the 18 ADCS-ADL-MCI items had correlations of > 0.30 with the total score, generally suggesting low item homogeneity . In contrast, item-total correlations were higher at month 36, with all but one item (item 7) having correlations between 0.30 and 0.70. Acceptable internal consistency was demonstrated at baseline with an overall Cronbach's alpha value of 0.64. Cronbach's alphas with each item omitted were largely similar, ranging between 0.58 and 0.64. Similar to the item-total correlations, Cronbach's alphas were higher at month 36 , indicating good internal consistency. Cronbach's alphas with each item omitted were similar, ranging between 0.85 and 0.87  was supported with an ICC value of 0.73 and a minimal, non-significant change between baseline and month 6 , the ICC value for this group of patients was lower at 0.62, indicating moderate test–retest reliability .Test–retest reliability among stable patients based on the MCI-CGIC, GDS and CDR-SB  based on the GDS, MMSE, BDI, and CDR-SB at baseline and month 36 .In view of known-groups validity, the ADCS-ADL-MCI was able to differentiate patients by disease severity . This finding suggests these questions were not assessing abilities but rather usual activities.The ADCS-ADL-MCI demonstrated moderate evidence of internal consistency. While item-total correlations were overall acceptable at month 36, at baseline there were generally poor correlations for most items. These findings were anticipated as variability in responses are known to increase with increasing disease severity and items with higher response variability are expected to show stronger correlations with the total score , 25. Of Further, items with strong sex effects  also had low item-total correlations (< 0.30), indicating that they behave systematically different from the other items. Finally, the Cronbach’s alpha measure of internal consistency was acceptable, with a Cronbach's alpha of 0.64 at baseline, and 0.87 at month 36 . The lacReproducibility, defined by test–retest ICC, of the ADCS-ADL-MCI was moderate to good, especially as the timeframe between screening and baseline assessments (up to 6 months) was longer than typically desired . In general, the ICC was higher when using the MCI-CGIC, GDS and CDR-SB vs. MMSE to define stability. One reason may be that the MMSE has higher variability in the MCI population than the other measure. Nonetheless, given the widespread use of the MMSE in this population, it was deemed important to explore 'stability' according to the MMSE as well.The convergent validity of the ADCS-ADL-MCI with other relevant COA measures defined a priori showed moderate to high correlations. The ADCS-ADL-MCI was moderately correlated with the CDR-SB total score in the baseline measurement cohort. At month 36, strong correlations were observed between the ADCS-ADL-MCI total score and all the COA instruments evaluated, except for the BDI, Qol-AD-Informant total score, and NYU delayed paragraph recall test (moderate correlations observed). While a few of these results were contrary to expectations , they indicate that functional, behavioral, and cognitive symptoms are all affected by (mild) cognitive impairment, particularly in a cohort with increased variability in disease presentation. Further, The ADCS-ADL-MCI likely had the strongest correlations with the CDR-SB as both measures assess functional aspects, whereas the MMSE and ADAS-Cog address predominantly cognitive aspects.APOE ε4 allele carrier status at month 36 but not baseline as expected, which confirms that the presence or absence of a biomarker when other clinical parameters are matched does not seem to differentiate ADL impairments in this early stage of the disease.Further strong support was found for the known-groups validity of the ADCS-ADL-MCI, which is in line with previous publications , 16, 21.Finally, there was good support for the responsiveness of the ADCS-ADL-MCI, i.e., the instrument was adequately responsive in patients who indicated change in other instruments; and it was adequately stable in patients who did not show change in other instruments . Curiously, the 'improved' group according to CDR functional domain showed a marginal decrease in ADCS-ADL-MCI scores. Further, for the GDS, the two categories' improved' and 'no change' showed decreases in ADCS-ADL-MCI scores, with the former group showing even larger reductions than the latter group. Given that no confirmation of underlying AD or other neurodegenerative pathology was confirmed in this trial, it is plausible that some participants who meet criteria for MCI could subsequently “revert” to normal cognition. However, MCI patients reverting back to normal still remain at higher risk of progressing to dementia . FurtherStrengths of the study include a relatively large sample size that enabled us to carry out all psychometric tests planned and trust that results are robust, especially given that the sample was based on a diverse population in terms of age, education, and years since disease onset. Besides that, the ADC-008 trial dataset included an extensive range of COA instruments that enabled us to use these as reference instruments to assess various psychometric properties. Further, given that the study used data from an interventional clinical trial, tests of sensitivity to change over time were possible as the objective change had occurred in many trial participants over the 36-month duration of the trial.APOE ε4 allele carriers are more likely to have underlying AD pathology and progress to dementia faster, it was of interest to examine whether there were more or less carriers at this timepoint. The proportion of APOE4 carriers was similar at baseline and month 36.The present study also has some limitations. For example, our target instrument was assessed at baseline, while some of the reference COA instruments had only been assessed at the screening assessment. Hence, while it is not expected that large changes occurred between these two time points, for the purpose of our project, it would have been preferable to have all COAs assessed at the same time point. However, we responded to this potential limitation by using 36-month data for our psychometric tests as well. The 36-month timepoint has limitations in that it only includes the aMCI patients who have not progressed to dementia, e.g., a more slowly progressing population. Thus, while the sensitivity to change reported herein may represent a conservative estimate, this reflects somewhat of a strength in that the psychometric property is shown in a more conservative sample. Given that Further, the two-step response process to most ADCS-ADL-MCI items poses some challenges for psychometric evaluation. For example, scale-level tests such as factor analysis on gated items are more challenging than those on questions with thoroughly graded responses. Therefore, we could not confirm nor deny the unidimensionality assumption of the ADCS-ADL-MCI. However, our results suggest that the ADCS-ADL-MCI performs well across multiple psychometric tests despite this limitation. The diversitiy of the enrolled clinical cohort was poor, with 92% of the cohort “white, not of Hispanic Origin”. While the inclusion criteria for the study was extensive to confirm amnestic MCI, subjects were not required to have evidence of amyloid or tau pathology, thus the application of these findings to MCI patients on the AD continuum can be considered an extrapolation on the basis that a clinical diagnosis of amnestic MCI is the same regardless of the underlying disease pathology. It is nonetheless important to note that patients with MCI may not necessarily have underlying AD. Finally, a caveat to the use of informant-based methods is reliance on the caregiver’s knowledge about patient’s daily activities. As such, the accuracy of these reports is somewhat limited to the amount of care provided by the informant.Overall, findings from this study suggest that the ADCS-ADL-MCI is reliable, valid and responsive to change in an amnestic MCI population. However, further investigation is needed in this sample, and a comparison of performance-based measures, self-report and informant-report measures may help define functional impairment in MCI (in terms of quanitifable cut-off scores) more precisely.In conclusion, this study provides supportive evidence that the ADCS-ADL-MCI is reliable, with acceptable internal consistency  and moderate-to-good reproducibility. Convergent validity was demonstrated, with moderate-to-high correlations observed between the ADCS-ADL-MCI with other relevant COA measures. Further, there was strong support for known-groups validity, as evidenced by the ADCS-ADL-MCI’s ability to distinguish between various disease severity groups. Finally, the ADCS-ADL-MCI was shown to be responsive to change when patients reported change on other COA measures. This instrumentis fit-for-purpose as a key endpoint in pivotal trials and for use by clinicians in clinical practice, capable of capturing amnestic MCI patients' functional abilities in ADLs from a caregiver's perspective.Additional file 1: Supplemental Table 1. Distribution of ADCS-ADL-MCI individual item scores at baseline by sex. Supplemental Table 2. Distribution of ADCS-ADL-MCI individual item scores at month 36 by sex.


Hearing impairment (HI) is characterized by unilateral hearing loss in one ear and can result in learning difficulties, language impairment and socio-emotional difficulties. To assess the perception of hearing handicap in adult subjects, patients with unilateral sensorineural HI, non-users of individual hearing aids. Materials and Methods: Prospective study with 52 adult subjects with a mean of 34.5 years of age, from both genders  with hearing loss: sensorineural unilateral, in varying degrees, responded to a questionnaire for assessing hearing handicap, and for that we used the Hearing Handicap Inventory for Adults (HHIA).Results: We scored the subscales of the emotional and social/situational aspects, and we found 73.1% of the handicap present being mild, moderate and significant, but at a higher percentage (88.5%) in females.Conclusions: The use of the questionnaire proved to be an effective procedure, because the unilateral HI may, not infrequently, compromise social and emotional aspects of the adult subject and the same degree of HI who can react differently, indicating that the wide variability in the perception of the hearing handicap is associated with non-audiological aspects.Unilateral hearing loss is that which occurs in one ear; it affects mostly in males.Unilateral hearing loss individuals find academic life harder, present language difficulties and face social and emotional hurdles.The effects of unilateral hearing loss are as important as those caused by bilateral hearing loss in the presence of ambient noise. These individuals find it harder to understand speech, compared to normal hearing persons, even when the normal ear is well positioned towards the source of speech; spatial location of sources of sound is affected.Problems due to sensory deprivation may be minimized by using a personal sound amplification device (hearing aid); it makes it possible to retrieve ambient and speech sounds, which improves the ability to communicate.The decision to use a hearing aid begins with self-perception of the auditory handicap. According to a model proposed by the World Health Organization (WHO),It has been said that of all sensory disabilities, loss of communication with other people may be one of the most frustrating consequences for individuals with hearing loss.ResearchersThe HHIA was standardized in a sample of 67 adults with hearing loss,In the present study, we chose to use the term handicap, rather than “disadvantage,” since it is a widely used English term in the scientific community and expresses better the concept to which it refers.The purpose of this study was to assess self-perception of auditory handicap in adults with unilateral sensorineural hearing loss not using hearing aids.The selection and assessment procedures of patients started after the institutional review board approved the study (Protocol 123/98) and patients signed the free informed consent form.This cross-sectional contemporary cohort study included 52 adults of both genders , with a mean age of 34.5 years.The participant inclusion criteria were:–Age: adult from 18 to 60 years;–Hearing loss: unilateral sensorineural of varied degrees;–Presence of hearing loss for more than one year;–Non-users of hearing aids.Of 5,000 regularly registered patients, 77 fit into these study criteria; 52 of these subjects agreed to participate in the study.There were several etiologies according to the diagnoses made by the otorhinolaryngologist of the institution: cranial trauma (3), parotiditis (4), cholesteatoma (1), measles (1), sudden deafness (3), noise-induced hearing loss (1), vestibular syndrome (1), idiopathic (1), complication of chronic otitis media (1), otosclerosis (1), and of unknown cause (35).The degree of hearing loss was given based on the audiometric thresholds at 500, 1000, 2000 and 4000 Hz: mild hearing loss (mean – 26 to 40 dBHL), moderate hearing loss (mean – 41 to 60 dBHL), severe hearing loss (mean – 61 to 80 dBHL), and profound hearing loss (mean over 81 dBHL), based on WHO criteria.14The devices used for the exams were as follows: a model SD50 audiometer with HDA200 headphones, and a model SD30 impedance meter, both from Siemens.The Portuguese version of the HHIA questionnaire15 (Annex 1) was used for evaluating the handicap; question 1S was adapted from: “Does difficulty in hearing make you use the telephone less than you wish?” to 1S: “Does your difficulty in hearing bring you problems when using the telephone?”The HHIA is a self-assessment questionnaire of auditory handicap comprising 25 items, of which 13 deal with emotional aspects (E), and 12 deal with social and situational aspects (S). For each item or situation, subjects are asked to give one of the following answers: “yes” (4 points), “sometimes” (2 points) or “no” (0 points).The questionnaire was applied individually by the investigator. Explanations were given if there were doubts about each question; care was taken not to induce answers, to avoid interviewer bias.Scores ranged from zero to 100 percent; the score correlated with handicap perception, where a high score suggested a significant perception of hearing loss by the subject. Thus, a zero to 16 score indicated absent handicap; an 18 to 30 score indicated a mild handicap; a 32 to 42 score indicated a moderate handicap; and scores over 42 indicated a significant handicap.Although this was not the purpose of the study, participants underwent a hearing aid selection and adaptation process, and again answered the HHIA questionnaire after six months of effectively using the hearing aid. This procedure was carried out to check whether the handicap could be changed by using a sound amplification device.Spearman's correlation coefficient was used to verify whether the handicap correlated with age, degree and duration of hearing loss. The chi-square test was applied to verify any association between handicap and gender. The significance level in all tests was 5% (p<0.05).The emotional and social/situational subscales of 52 subjects who answered the HHIA questionnaire were scored. Assessing and analyzing the restrictions that individuals with unilateral hearing loss have in their daily lives provided us with knowledge about the effects of this condition on communicative, social and emotional aspects that make it possible for such persons to reflect about these factors and to understand their needs. Thus, considering that subjects with a similar audiometric profile may perceive their condition differently, and that traditional audiometric exams yield only basic information about a person's hearing ability, it becomes essential to assess communication difficulties and social and emotional consequences of hearing loss, which may be done by applying self-assessment questionnaires.Disadvantages due to hearing loss may appear in social and emotional situations. The distribution of the responses in the emotional subscale  revealedThis shows the importance of applying these questionnaires, which make it possible to investigate the patient's perception about their communication difficulties; it also facilitates monitoring and helping these patients to identify their hearing needs, as well as those that are found in routine audiological assessments.The distribution of responses in each item of the social/situational subscale  revealedSubjects may face several speech understanding difficulties in noisy environments, as the number of cues decreases significantly, and they find themselves having to use only those cues available in that situation.The observed difficulty in gathering data about telephone use  was unexCorrelating gender and the presence/absence of an auditory handicap  revealedWe found no statistically significant correlations between the degree and the duration of hearing loss ; most suThe HHIA questionnaire investigates whether hearing loss has altered the behavior of subjects in daily situations, as well as their attitude and response to this loss. Each subject reacts differently to hearing loss. Therefore, a mere pure tone analysis does not establish the extent of auditory handicap or the impact that hearing loss has on the daily lives of people.The HHIA has proven itself an excellent tool for predicting and confirming the performance of hearing impaired subjects in relation to communication difficulties in a variety of contexts; it may thus be of help in defining the amplification and rehabilitation needs, which are both directly linked with the patient's expectations and perception.The importance of the HHIA questionnaire in this study was underlined by reapplying the questionnaire six months later in the same sample, after effectively using hearing aids, and finding significant changes in the scores; this finding suggests that subjects perceived better their hearing impairment.In this study we hope to have provided additional information about the consequences of unilateral hearing loss in adults, and to foster an interest in further studies about this topic, with an emphasis on rehabilitation.Unilateral hearing loss may affect the social and emotional aspects of adults with this condition; these individuals require appropriate interventions.Females had a higher perception of their handicap compared to males.Subjects with the same degree of hearing loss may react differently, suggesting that the wide range of perception of an auditory handicap is associated with non-hearing factors.