Patients undergoing cardiac surgery represent a challenge in terms of pain management due to multiple factors relating to the patients and to the procedure itself. Our aim was to identify the influence of levels of preoperative anxiety on postoperative pain in patients undergoing cardiac surgery and explore associations between preoperative anxiety, postoperative pain, analgesic requirements, and sex. We present a prospective cohort study of 116 patients undergoing cardiac surgery between January and April 2020. Preoperative anxiety was evaluated using the State-Trait Anxiety Inventory and the amount of morphine needed to keep pain intensity below 4 on the verbal numerical rating scale was recorded for 48 h post-surgery. Given the extracorporeal circulation time, type of surgery and body surface, it was observed that every percentile increase in preoperative state anxiety led to an extra 0.068 mg of morphine being administered. For each extra year of age, the amount of morphine needed decreased by 0.26 mg, no difference was observed between men and women in terms of preoperative anxiety or postoperative analgesics requirements. It may be concluded that in cardiac surgery, postoperative analgesic requirements increased with higher levels of preoperative state anxiety and decreased for every extra year of age. Inadequate analgesia during the postsurgical period can lead to adverse cardiovascular responses, such as hypertension, tachycardia, vasoconstriction, haemodynamic instability, and high incidence of postoperative myocardial infarction. This increase in morbidity may interfere with extubation time, resulting in longer hospital stays and higher overall costs3. Patients undergoing cardiac surgery pose a challenge when it comes to pain management because of the multiple, diverse characteristics of each patient and procedure, so many tools for evaluating postoperative pain have been validated among cardiac surgery populations1.In patients undergoing cardiac surgery, postoperative pain is one of the main causes for concern. Recent studies show that, during the postoperative period, 47% to 75% of patients experienced pain. This pain is often severe and insufficiently treated4. Factors such as optimism, depression, chronic pain  and catastrophic pain have also been linked to acute postoperative pain from cardiac surgery5. Within strictly surgical factors, time of extracorporeal circulation and type of cardiac surgery affects the overall recovery including postoperative pain6.Significant factors predicting greater sensitivity to postoperative pain from cardiac surgery include: experiencing preoperative pain, feeling anxiety, being younger, and being female8. Preoperative anxiety can cause haemodynamic issues during the intraoperative period, increased need for analgesics, and poorer patient satisfaction in the postoperative period8. Given this, the recently updated guidelines from the European Society of Anaesthesiology recommend incorporating anxiety assessment into preoperative patient assessments9.Research has linked higher levels of preoperative anxiety to greater postoperative pain10. The inventory’s authors identify two types of anxiety: a temporary state or State Anxiety (SA), and a stable latent trait or Trait Anxiety (TA). SA is conceptualised as a transitory emotional state or condition of the human body that is characterised by subjective feelings of tension and apprehension, which are consciously perceived, as well as a hyperactive autonomic nervous system. It can vary over time and fluctuate in intensity. TA is a relatively stable propensity for anxiety, making individuals more likely to perceive situations as threatening and exacerbating their SA11.One of the most reliable and most widely used tools to measure preoperative anxiety in cardiac surgery is the State-Trait Anxiety Inventory (STAI)12. It has also been suggested that women are more sensitive to pain. Although the reasons for this remain unclear13. The considerable differences in men and women’s molecular and cellular genetic mechanisms and systems for processing acute and chronic pain are undoubtedly affected by the interaction between sex and other sociocultural factors, and this is likely to play an extremely important role in experiences of pain14.Studies have shown that women experience higher levels of persistent pain up to a year after cardiac surgery, although they note that this may be linked to a lower intake of analgesics15.Postoperative pain is a complex, multifactorial phenomenon and an important prognostic predictor among cardiac surgery patients. The notion of individualised pain management based on associated factors needs further research in order to be applied to the development of tools for predicting who will experience increased pain and need more analgesia, or for the early implementation of interventions to reduce modifiable factors, such as preoperative anxietyThe relationship between preoperative anxiety and postoperative pain becomes apparent. This study differs from previous publications in that it links preoperative anxiety not only to the degree of pain reported by patients in the immediate postoperative period, but also to the degree of analgesia necessary to keep pain at a mild level.This study aims to identify the influence of levels of preoperative anxiety on predisposition to postoperative pain in patients undergoing cardiac surgery based on analgesic requirements, as well as to explore the relationship between preoperative anxiety, postoperative pain, and sex.This prospective cohort study of patients undergoing cardiac surgery evaluated preoperative anxiety levels as a factor influencing immediate postoperative pain.Patients aged over 18 undergoing elective cardiac surgery at a tertiary hospital run by the Castile and León Regional Health Management Board, Spain, between January and April 2020. The following types of cardiac surgery were covered: coronary revascularisation (a graft using the mammary artery or the saphenous vein) and/or valvular (repair or replacement) surgery. All of them with sternotomy and extracorporeal circulation. Patients who did not consent to participate in the study after receiving information about it were excluded. A total of 13 patients were excluded: 1 exitus occurred in the first 24 h after surgery, 8 patients were unable to perform the preoperative anxiety test due to last minute changes to the surgery schedule, and 4 patients provided incomplete data on postoperative pain. A total of 116 patients who met the inclusion criteria were finally included. The optimal sample size was set at 113 participants with a 95% confidence interval, an accuracy of 0.5 units, and a standard deviation of 2.5 units for mean postoperative pain. The replacement rate was set at 15%.Data were collected on: (a) sociodemographic variables: age and sex; (b) most common comorbidities and toxic habits in the last month ; (c) type of cardiac surgery , and extracorporeal circulation time (minutes); (d) psychological variables: SA/TA level ; (e) analgesic requirements in the postoperative period: milligrams of morphine hydrochloride required to maintain pain below 4 on the verbal numerical rating scale (vNRS), which ranges from 0 (no pain) to 10 (maximum pain) and, (f) body surface calculated with height and weight. About analgesic requirements, it is known that weight or body surface area makes a difference in the morphine dosage recommendations. The drugs administered during surgery (fentanyl and etomidate or propofol and rocuronium bromide) were not taken into consideration, as they were used according to protocol.16. Centile scores were used in this study. Patients were asked to respond to the items on the SA scale, which ranges from 0  to 3 (a lot), and the TA scale, which runs from 0  to 3 . The minimum direct score was 0 and the maximum was 60 for both subscales, and this score was then converted into the corresponding centile. Two members of the research team administered the questionnaires in all cases, giving patients the same instructions for completing the questionnaire to reduce potential bias17.In the 24 h prior to surgery, patients in the cardiac surgery inpatient unit who met the inclusion criteria were informed of the study objectives and asked for their informed consent. After they had signed the informed consent form, the patients completed the Spanish version of the State-Trait Anxiety Inventory (STAI). This psychometric questionnaire comprises two scales measuring different facets of anxiety: state and trait anxiety. The STAI contains 40 items. Half of the items belong to the State subscale, which is made up of phrases describing how the respondent feels at that specific moment. The other half belong to the Trait subscale, which encompasses phrases describing how the respondent usually feels. The Spanish adaptation of the questionnaire has good internal consistency at 0.90–0.93  for the State subscale and 0.84–0.87  for the Trait subscale. In the Spanish version, the direct scores corresponding to the sum of the items have been converted into centile and sten scores, which are obtained according to the sex and age indicated by the authors of the Spanish adaptation18.After their surgery, patients’ pain was evaluated and monitored in the Cardiac Recovery Unit throughout the first 48 h post-surgery. The first 48 h after surgery were selected as the follow-up period for measuring patients’ pain, as several studies have identified this as the most painful period following cardiothoracic surgeryEvaluation of postoperative pain was carried out once patients had been extubated and were able to verbalise their pain. The vNRS scale was used to measure their pain (0: no pain and 10: maximum pain). Pain intensity was recorded every two hours in two daily shifts: morning (08:00 to 15:00), evening (15:00 to 22:00) and night (22:00 to 08:00). Patients’ sleep was respected during the night shift, with at least two measurements taken at 00:00 and 06:00. The maximum pain values recorded in each shift throughout the course of the 48-h monitoring period were used for the study.The protocol for managing cardiac surgery patients’ postoperative pain at the Cardiac Recovery Unit offered two options based on medical criteria: (A) Analgesic combination of 1 g of paracetamol every 8 h and 50 mg of dexketoprofen every 8 h administered alternately and (B) 1 g of paracetamol every 8 h and 2 g of metamizole magnesium every 8 h administered alternately. In addition, whenever patients expressed pain exceeding 4 on the vNRS scale, IV boluses containing 3 mg of morphine hydrochloride were administered as ‘rescue doses’. The ‘analgesic requirements’ variable was measured by calculating the total milligrams of morphine hydrochloride required by patients over the 48-h period.The study was conducted in line with the principles stated in the Declaration of Helsinki. The permission to conduct the study was approved by the Clinical Research Ethics Committee of the East Valladolid Health Area (Reference Number: GR-19-1253).t-test was used to compare two groups of quantitative values and ANOVA was used to compare more than two groups of quantitative values. To analyse the degree of association between quantitative variables, Pearson’s correlation coefficient was used. A univariate linear regression model was performed to identify the factors linked to the dose of morphine received by each patient. Variables found to be statistically significant at the 0.1 level in the previous analyses were entered into a multivariate linear regression model. The performance of association of the model was calculated with the coefficient of determination R-squared (R2). The statistical significance threshold for all tests was set at p < 0.05.Data were analysed using the IBM SPSS Statistics for Windows, Version 24.0. Armonk, NY: IBM Corp. Quantitative variables were expressed as means and standard deviations. Qualitative variables, in terms of their frequency distribution. The assumption of normality was assessed using the Kolmogorov–Smirnov test. Associations between qualitative variables were explored using Pearson’s chi-squared test. When more than 20% of the cells had expected values under 5, Fisher’s exact test or the likelihood-ratio test for variables with more than two categories was used. Student’s A sample of 116 patients comprising 68% men and 32% women was analysed. The mean age was 70 years old (standard deviation (SD) = 8.08). 23.3% (n = 27) of the patients underwent coronary cardiac surgery, 55.2% (n = 64) underwent valvular coronary surgery, and 21.6% (n = 25) underwent mixed surgery. The mean extracorporeal circulation time was 107.73 min (SD = 42.42).The most common comorbidities were, 49.1% (n = 57) experienced high blood pressure and 19.8% (n = 23) diabetes. Only one patient (0.9%) reported suffering from chronic pain  for SA, and a median of 30 for TA .The mean value for postoperative pain was 3.57 SD = 1.81) on the vNRS scale. The mean dose of morphine needed as a rescue dose was 13.21 mg (SD = 7.59). The pain intensity verbalised by patients decreased significantly throughout the evening, night, and morning shifts in the 48-h follow-up period (p < 0.001) .Based on univariate analyses the following variables that were significantly related to postoperative morphine use at a 0.1 level, were entered in the multivariate model: rescue medication corrected for body surface area, extracorporeal circulation time and type of surgery,2) obtained in the multivariate linear regression model was 0.77. This result indicates that the percentage of variability explained for pain taking into account milligrams of morphine and state anxiety is good. The results of the multivariate linear regression model can be seen in Table Patients with higher levels of preoperative SA were found to need more morphine hydrochloride to keep their pain level below 4 on the vNRS p = 0.029). On average, every percentile increases in SA required an extra 0.068 mg of morphine hydrochloride in the rescue doses administered. Considering age, every extra year of age reduced morphine hydrochloride requirements by 0.25 mg (p = 0.017). The coefficient of determination  see Fig. .Figure 2No differences between men and women were found in the mean postoperative pain intensity measured using the vNRS (p > 0.05) see Fig. .Figure 3Men had a higher mean body surface, 1.92 (SD = 0.20) than women, 1.69 (SD = 0.16), (p < 0.001). Men required an average of 7.247 mg of morphine hydrochloride for each unit of body surface area and women required 6.254 mg for the same unit of body surface area. There were no significant differences in analgesic requirements in milligrams of morphine hydrochloride, between men and women, to keep their pain level below 4 on the vNRS (p = 0.241).19. In this study, patients experienced a decrease in the mean intensity of pain over the course of successive shifts in the first 48 h of the postoperative period, maintaining values within the range of moderate to mild pain (mean level of pain below 4 on the vNRS). Only at day one the afternoon mean pain score was > 4, coinciding with the first hours after surgery.Thoracic surgery requiring sternotomy can be very painful, with movement, coughing, and respiratory physiotherapy exacerbating the pain20.In our study population, higher levels of preoperative SA proved to have a negative impact on the immediate postoperative period, increasing the analgesic requirements needed to keep patients’ pain below 4 on the vNRS. This finding offers an opportunity for intervention, as SA is a variable that can be modified via effective intervention to reduce preoperative anxiety and influence postoperative pain. Although several techniques have been identified for reducing anxiety, it is unclear which is the most effective. Interventions that have proved effective in reducing preoperative anxiety include ‘orientation tours’, in which patients visit the operating theatres and several inpatient units, where healthcare professionals explain their functioning and patients are able to share experiences with hospitalised patients before undergoing surgery21. One of the strengths of our study is the fact that it does not compare preoperative anxiety with postoperative pain itself but with the analgesic requirements needed to keep postoperative pain in the mild range, below 4 on the vNRS. To assess the analgesic needs of patients in order to keep pain intensity for mild to moderate pain (vNRS ≤ 4) in such painful surgery, could be considered as an indicator of adequate pain management in these patients. On the one hand analgesics need to be administrated regularly for moderate–severe pain and, on the other, patients need to be encouraged to communicate their pain with nurses.A number of studies have explored the role of psychological interventions in reducing pain intensity in patients undergoing cardiac surgery, obtaining no conclusive findings as to their effectiveness in reducing postoperative pain, although most of these studies did not consider postsurgical analgesic requirements6. Besides, pain scores have been related to the type of surgery, some previous studies identified that patients having coronary artery bypass grafting (CABG) with Left Internal Mammary Artery (LIMA) and valvular surgery were more likely to have higher levels of pain than those having CABG without LIMA22.Given the multifactorial nature of pain, extracorporeal circulation time and the type of surgery were taken into account as influential factors. The literature reports that patients undergoing cardiac surgery with the use of extracorporeal circulation report a slightly greater intensity of pain than those in whom extracorporeal circulation is not used, as it is associated with the induction of the systemic inflammatory response syndrome23. There was also a decrease in analgesic requirements for every extra year of age, other studies have confirmed that the pain threshold rises with age24. Since our findings on sex refer specifically to postsurgical pain measured via analgesic requirements, they may differ from studies concluding that women are more sensitive to chronic pain13. However, our results corroborate recent studies finding increasing evidence that sex specific differences in pain are not clear. Even more controversial is the effect of sex on opioid consumption after surgery. Although morphine seems to be more effective in women compared to men, clinical trials investigating sex differences of perioperative morphine consumption showed conflicting results, in this way, female sex is not considered a risk factor for pain after surgery25.In our study population, no differences in preoperative anxiety were found between men and women, despite some studies observing higher levels of anxiety among womenExploring associations between preoperative anxiety, perceptions of postoperative pain, and analgesic requirements may help us to plan pain management for patients undergoing cardiac surgery and deliver person-centred care. Nursing interventions could be designed to reduce postoperative pain by including an evaluation of state anxiety in the preoperative protocol for cardiac surgery. These results should be validated in other cohorts and hospital settings.Limitation is linked to the use of a convenience sample of patients undergoing cardiac surgery in a specific hospital, which helped with meeting the study objectives but makes it difficult to generalise the results. Besides, preoperative pain has not been measured, which could be a risk of bias due to a possible association with postoperative pain.Postoperative analgesia requirements increase with higher levels of preoperative anxiety and decrease with each additional year of age, regardless of sex. Therefore, higher levels of preoperative state anxiety and lower age appear to act as predictors of greater analgesia requirements in cardiac surgery patients. Nursing interventions could be designed to reduce postoperative pain by including an evaluation of state anxiety in the preoperative protocol for cardiac surgery. These results should be validated in other cohorts and hospital settings.


To alloBased on patient signs and symptoms, the DC/TMD defines two axes: (i) Axis I, categorizing the TMD into muscular TMD (Group I) and arthrogenous TMD (Group II and III); (ii) Axis II, assessing the disability due to the TMD pain through the evaluation of behavioral and psychological status .An overall prevalence of TMD patients of around 30% has been recently reported, consisting of around 45% for group I and 70% for groups II and III (taking into account the overlapping conditions) .The etiology of TMD has been accepted as multifactorial, and the suggested risk factors can include excessive muscle tension, grinding, clenching as a parafunctional activity, repetitive trauma to the joint, and bruxism . FurtherMyofascial pain prevalence is higher in primary pain conditions connected to the central nervous system, including headaches and other chronic conditions, most likely due to central sensitization ,4. IndeeIt has been shown in the scientific literature that the most common signs and symptoms of TMD patients are pain and the articular limitation of jaw motion; these might even induce disability during activities of daily living  with a consequent reduction in health-related quality of life .Furthermore, it has to be noted that the recent COVID-19 epidemic might lead to a higher frequency of TMD symptoms, interacting with the psychological and emotional status of the population . Indeed,The diagnosis is commonly performed according to DC/TMD and through cone beam computer tomography and magnetic resonance imaging exams, commonly required for the diagnosis of temporomandibular joint (TMJ) disorders . The MRIConcerning the treatment of TMD patients, the main objectives that should be focused on are: (i) reducing TMJ pain; (ii) reducing masticatory muscle pain; (iii) improving TMJ function; and (iv) avoiding further TMJ impairments ,10. In tLastly, telemedicine might allow us to monitor TMD patients over time, particularly during the COVID-19 pandemic, providing adequate feedback ,15. In tTherefore, multidisciplinary intervention is required for managing TMD pain, taking into consideration an appropriate diagnosis and all the interdisciplinary therapeutic approaches concerning the TMJs and the neuromuscular structures of the masticatory system. Further evidence is still needed to better characterize the physiopathology, diagnosis, and treatment of TMD patients.


Nine proteins separated TMDM from controls (p = 0.0174) and 12 proteins separated MYA from MFP (p = 0.019). Pain duration, characteristic pain intensity, pain catastrophizing, perceived stress, and insomnia severity were significantly associated with protein markers (p < 0.001 to p < 0.022). In conclusion, several plasma proteins were upregulated in TMDM and either upregulated or downregulated in MYA compared to MFP. Some proteins in TMDM were associated with pain variables, sleep disturbance, and emotional function. These results show that systemic differences in protein expression exist in patients with TMDM and that altered levels of specific plasma proteins are associated with different clinical variables.The aims of this study were (1) to compare the levels and interactions of several plasma proteins in patients with myogenous temporomandibular disorders (TMDM) compared to healthy and pain-free controls, (2) to compare the levels and interactions in two TMDM subgroups, myalgia (MYA) and myofascial pain (MFP), and (3) to explore associations between the proteins and clinical data. Thirty-nine patients with TMDM (MFP,  Chronic musculoskeletal pain is one of the major causes of illness with a great negative impact on the individual and the society. The International Association for Pain (IASP) estimates that one in five individuals world-wide suffers from chronic pain and it is the most common reason for health care seeking . Even ifIn the orofacial area, temporomandibular disorders (TMD) are the most common chronic pains affecting 5–12% of the population . It is mThe etiology of TMD is regarded as multifactorial and the Orofacial Pain Prospective and Risk Assessment (OPPERA) study suggested that a biopsychosocial model should be used for TMD to emphasize the importance of psychosocial and behavioral factors in the onset of TMD . NeverthTo explore the molecular mechanisms involved in the pathophysiology of human pain conditions biofluids are often analyzed. While many studies have analyzed molecular markers in pure articular TMDs, relatively few studies have been conducted in TMDM . HoweverPrevious techniques only permitted analyses of a few molecules at a time and complex interactions between molecules could not be studied. However, recent developments in analytical techniques such as multi-panel arrays and omics have increased our ability to study multiple markers simultaneously. It was also proposed that multiple biomarkers should be assayed to understand the complexity of painful TMD, since concentrations of single markers may vary considerably between patients . Our resHence, the first aim of this study was to compare the levels and interactions of multiple plasma proteins in TMDM compared to healthy and pain-free controls as well as between its diagnostic subgroups MYA and MFP. A second aim was to explore associations between proteins and clinical data in TMDM.The null hypothesis was that there are no differences between TMDM patients and controls, or MFP and MYA in plasma protein concentration of the investigated markers and that there are no correlations to clinical data.This prospective case–control study is a sub-study of a project investigating salivary and plasma biomarkers in TMDM. The recruitment process has previously been described in detail . The preInclusion criteria for the TMDM group were (1) a DC/TMD diagnosis of MYA or MFP , (2) a pThe study was conducted at the Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden and followed Good Clinical Practice and the guidelines of the Helsinki Declaration. One experienced researcher (HJ) calibrated to a DC/TMD reference standard examiner  examined all participants and collected the data. All participants received both verbal and written information about the study and gave their written consent. The study was approved by the Regional Ethical Review Board in Stockholm, Sweden .The participants were first asked to complete a questionnaire with questions regarding general and oral health, medications, and validated instruments for assessment of pain variables and physical as well as emotional function. This was followed by a clinical examination according to the DC/TMD examination protocol, which includes confirmation of pain location, mandibular mobility and pain on movement, temporomandibular joint (TMJ) noises, and TMJ and muscle palpation . The par2 connected to a handle with a pistol grip. The examiner placed the tip of the algometer on the relaxed muscle and slowly increased the pressure (50 kPa/s). When the participants felt that the pressure turned into the slightest painful sensation, they pushed a stop button, and the display momentarily froze and the PPT value was noted in the protocol. The PPT was recorded three times over the most prominent part of the masseter muscle as well as over the tip off the index finger (thumb) on the most dominant side. The mean of the three recordings was used in the analyses [The PPT was recorded using an electronic algometer . The device consists of a rod with a pressure sensitive strain gauge with an area of 1 cmanalyses .The questionnaire used was an extended version of the DC/TMD Axis II questionnaire . The folSelf-reported physical activity was scored according to frequency with three levels, 1–2 times per month, 1–2 times per week, and ≥3 times per week .This form contains questions about presence and duration of orofacial pain and headache and if they are influenced by jaw function, and presence of joint sounds, and TMJ catchings/lockings. It is mainly used for diagnostic purposes together with the clinical examination .The GCPS v.2 is used for assessment of pain intensity and pain interference. Three questions are used to calculate the Characteristic Pain Intensity , which is based on the current pain intensity, the average, as well as the worst pain intensity during the last month, assessed on a 0–10 numeric rating scale (NRS). The mean value of the three scores is then multiplied by 10 to obtain the CPI. For pain interference, three other 0–10 NRS scales regarding interference in daily, social, and work activities are completed to calculate the interference score in the same manner as the CPI. Finally, disability points (0–6) are determined from the interference score  and added to the score for number of days of interference during the last month . The Chronic Pain Grade is then determined: Grade 0 = None, I = Low disability with low pain intensity; II = Low disability with high pain intensity; III = Moderately limiting, and IV = Severely limiting ,23. The JFLS consists of 20 questions, each scored on a 0–10 NRS, that assesses masticatory limitation (Q 1–6), vertical mobility limitation (Q 7–10), and verbal and non-verbal communication limitation (Q 13–20). A sum can be calculated for each of these three domains as the mean of the scores for the available questions. A total score can also be calculated as the mean of the score for Q 1, 3, 6, 10, 11, 12, 13, and 19. Norms have not been established yet for the instrument ,24.The PHQ-9 consists of nine questions that assess depressive symptoms. Each question is scored 0–3 . The total score (0–27) is calculated. Scores of 5, 10, 15, and 20 represent cut-off points for mild, moderate, moderate-severe, and severe depression, respectively ,25.The PHQ-15 was used to assess non-specific physical symptoms, such as headache, stomach pain, dizziness, and shortness of breath. Its 15 questions are scored 0–2 where 0 = not bothered, 1 = bothered a little, and 2 = bothered a lot. The total score (0–30) is calculated and cut-off values of 5, 10 and 15 represent mild, moderate, and severe physical symptoms, respectively ,26.The GAD-7 consists of seven questions that score anxiety. The questions are scored 0–3 according to frequency, exactly as the PHQ-9. Thus, the total score is 0–21 with the same cut-off values as for the PHQ-15 ,27.The PCS is composed of 13 questions assessing thought and feelings a person may have while being in pain. Each question is scored 0–4 according to frequency where 0 = not at all, 1 = to a slight degree, 2 = to a moderate degree, 3 = to a great degree, and 4 = all the time. The total score (0–54) is calculated. A score of 30 represents a clinically relevant level of catastrophizing .The PSS-10 was used to assess the level of stress. It comprises of six negatively and four positively phrased questions that are scored 0–4 . The scores for the positive items are reversed when calculating the total score (0–40) . NormatiThe ISI consists of seven questions that each are scored 0–4. The three first questions regarding insomnia are labelled none, mild, moderate, severe, very severe and the four last questions not at all, a little, somewhat, much, and very much. The total score is calculated and 8, 15, and 22 represent cut-off values for mild, moderate, and severe insomnia, respectively .The OHIP-5 was used to assess oral health-related quality of life. This ultra-short questionnaire has five response options scored 0–4 for each of the five questions  and the total score is calculated. A score of 0–7 is regarded as no, 8–15 as low, and 16–20 as high impact ,34.g for 20 min according to the manufacturer’s recommendation. The plasma fraction was aliquoted in 0.5 mL Eppendorf vials and stored at −80 °C until analysis.Blood was drawn from the decubital vein according to standard routine and was collected in an 8.5 mL tube . All samples were drawn in the morning under fasting condition. The blood samples were centrifuged at 2.500× The U-PLEX Metabolic Group 1 (hu) 87-plex , Gaithersburg, MD, USA) was used for analyses of plasma samples. It is a panel of 87 biomarkers  that conp < 0.05. The normality of the data was analyzed with the Shapiro–Wilk’s test. Mean (SD) or median , depending on normality, was used to describe the data. Comparison between groups in background variables was done with Student’s unpaired t-test for normally distributed data on a continuous scale and Mann–Whitney U-test for skewed or ordinal data. Differences in frequencies between groups were analyzed with chi-square test.Data were first analyzed with univariate statistics using SigmaPlot v.14  using a significance level of 2 describes the goodness of fit, i.e., the fraction of sum of squares of all the variables explained by a principal component whereas Q2 describes the goodness of prediction, i.e., the fraction of the total variation of the variables that can be predicted by a principal component using cross validation methods. R2 should not be considerably higher than Q2; if substantially higher (>0.3) the robustness of the model is poor [p-value was used. The OPLS-DA model was considered of significant importance if the CV-ANOVA had a p-value < 0.05.Since univariate statistics can only be used to analyze one protein at a time and our set of data consisted of 87 proteins that are more or less interrelated, we used multivariate statistics to identify correlations between biomarkers and other variables using SIMCA-P+ v.17.0  as earlier described . The rec is poor . To valiAnthropometric data of the patients and CON are shown in Subgroups MYA and MFP differed regarding occupation with less students in MFP. They also reported less frequent physical activity and higher reported oral health-related quality of life (OHIP-5) than MYA although still within the normal range.Pain variables are shown in More patients in the MFP than MYA group reported headache and PPTs were lower. The MFP group were also more frequently diagnosed with arthralgia and headache attributed to TMDM than MYA.The proteins were detected in plasma in 52–100% of samples, i.e., above the pre-set limit. The majority (60) were detected in 100% of samples and only 10 proteins were detected in less than 90% of samples. These proteins were IL-12p70 (87%), IL-5 (87%), IL-17A (80%), IL-29/IFN-L1 (77%), IL-2 (75%), IL-4 (72%), Active GLP-1 (65%), IL-31 (64%), IL-13 (62%), and IL-3 (52%).The PCA detected one strong outlier based on the score plots in combination with Hotelling’s T2 (identifies strong outliers) and distance to model in X-space (identifies moderate outliers). This participant, that was subsequently excluded from further analysis, belonged to CON.2 = 0.234, Q2 = 0.117, CV-ANOVA p-value = 0.0174)  . There w 0.0174) . As can  0.0174)  some pro2 = 0.499, Q2 = 0.224, CV-ANOVA p-value = 0.019). In this model 12 proteins , GLP-1 , GRO-alpha, IL-5, IL-7, IP-10, MCP-2, MCP-4, and TARC) separated the groups with a VIP > 1.0 and p(corr) > 0.40. Ghrelin (active) and GLP-1  were lower in MYA, all the others were higher in MYA compared to MFP , pain catastrophizing (PCS), perceived stress (PSS), and insomnia severity (ISI). Each model had different explained variation and predictivity, and from 8–13 significantly correlated proteins . Apart fThe main results from the present study were that of investigated 87 plasma proteins involved in inflammation and metabolism, nine were significantly higher in patients with TMDM compared to age-matched pain-free controls and 12 differed between MFP and MYA. We also found five significant regression models between proteins and clinical variables in TMDM. Thus, the null hypotheses were rejected.The nine proteins that differed between TMD and CON have different functions. Most of them are involved in the immune and inflammatory response, such as IL-6, IL-7, IL-1ra, BDNF, epithelial-derived neutrophil-activating peptide 78 (ENA-78), growth-regulated alpha protein , and YKL-40. Their levels were between 13 and 73 percent higher than CON. These proteins will be discussed below. Thyroid peroxidase (TPO) that participates in thyroid function and leptin that regulates the energy balance will not be discussed further.IL-6 is a multifunctional pro-inflammatory cytokine that stimulates the inflammatory and auto-immune processes in many diseases including systemic inflammatory diseases such as rheumatoid arthritis and systemic lupus erythematosus , but alsIL-7 is a pro-inflammatory cytokine released by many cells including immune cells and neurons. It seems to support aberrant immune activity in chronic inflammatory diseases such as rheumatoid arthritis, ankylosing spondylitis, and inflammatory bowel disease , but is Contrary to IL-6 and IL-7, IL-1ra is an anti-inflammatory cytokine. It is secreted by monocytes, macrophages, and neutrophils in response to acute-phase proteins and other cytokines and blocks the activity of IL-1 pathways involved in inflammation and pain and serves as an endogenous negative-feedback regulator to control potentially pathologic inflammatory events together with the other members of the IL-1 cytokine family . A few pIn a previous study from the same cohort as the present study, we found reduced saliva levels of BDNF, but increased plasma levels , which lENA-78, also known as CXCL5 is a chemokine that is produced during inflammation in response to the release of IL-1 and tumor necrosis factor alpha (TNF-α). It has been linked to sunburn-pain, arthritis, and atherosclerosis . In patiGRO-alpha or CXCL1 acts as a chemoattractant for immune cells and plays a role in the regulation of inflammatory and immune responses. It activates similar intracellular pathways as IL-8 and through these mediates sensitization by activation of NMDA receptors. It further contributes to prostaglandin release .YKL-40 or chitinase-3-like protein 1 is expressed by various cells, e.g., chondrocytes, macrophages, and smooth vascular cells. It has many biological functions, among these it modulates inflammation and has been linked to various diseases such as arthritis, inflammatory bowel disease, and cardiovascular disease. A recent study reported elevated levels in plasma and saliva of patients with peripheral neuropathy . In thatIL-7 was also among those 12 proteins that separated MFP from MYA. Of all these proteins, BDNF and GRO-alpha were the only ones that also differed between TMDM and CON. The concentration of BDNF and GRO-alpha were more than twice as high in MYA than in CON, with the concentration in MFP closer to CON than MYA. A similar pattern with higher levels was found for all the other proteins that separated MYA from MFP apart from GLP-1  and ghrelin (active) that were higher in MFP. This was unexpected and seemingly difficult to explain. However, on second thought this could make sense. One can speculate that, since MFP is a more severe condition than MYA with longer pain duration, higher pain intensity, and more comorbid conditions it could constitute a transition phase to more widespread pain , in whicWe found five OPLS models that significantly correlated plasma proteins to clinical variables, each with a set of eight to 13 proteins. However, several of the proteins were shared among the models, including IL-29/IFN-L1 (pain duration and CPI), IL-12p70 and GRO-alpha (CPI and pain catastrophizing), ENA-78 (pain catastrophizing and perceived stress), and I-309 and pro-insulin (perceived stress and insomnia). These models included some of the proteins that separated TMDM from CON. For example, BDNF, IL-7, ENA-78, and GRO-alpha were among those eight proteins that were associated with pain catastrophizing and GRO-alpha, IL-1ra, and TPO were associated with pain intensity. Further, IL-6 was associated with pain duration and ENA-7 with perceived stress. This further strengthens a role of these proteins in TMDM.This study has several strengths. The participants’ phenotype was well-characterized, patients and CON were well-matched for background variables, and the patients diagnosed using well-established and validated clinical criteria . Blood sAs is an exploratory study the reader may wonder about the clinical significance. Presently our results cannot be used when managing TMD patients. But since all current diagnostic classifications rely solely on subjective symptoms and clinical signs, management is unspecific and not directed to the cause of the pain. We therefore need more knowledge about mechanisms behind TMDM and if they differ between diagnoses such as MYA and MFP. Adding a third biomarker axis to the DC/TMD classification has been suggested to improve diagnostics and treatment . Since oIn summary, this study showed several plasma proteins that were upregulated in patients with TMDM compared to pain-free individuals and either upregulated or downregulated in MYA compared to MFP. Some proteins were associated with pain variables, sleep disturbance, and emotional function in TMDM. Combining these results confirms that systemic differences in protein expression exist in patients with TMDM compared to pain-free CON and that altered levels of specific plasma proteins are associated with different clinical variables.


The neurophysiological correlates of gastrointestinal symptoms (GISs) in Parkinson's disease (PD) are not well understood. It has been proposed that in patients with a gastrointestinal origin of PD dopaminergic neurodegeneration would be more symmetric.The aim is to assess the associations between GISs and asymmetry of nigrostriatal dopaminergic neurodegeneration in PD.123I‐FP‐CIT SPECT. We calculated the asymmetry index and the predominant side of motor symptoms and dopamine transporter (DAT) imaging defect and assessed their association with GISs.Ninety PD patients were assessed using motor and GIS scales and There were no significant differences in GISs between symmetric and asymmetric dopaminergic defect. Left predominant defect was related to more GIS and higher constipation scores.Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson Movement Disorder Society.GISs were associated with left predominant reduction in putaminal DAT binding but not asymmetry per se. It remains open whether left‐sided DAT deficit is related to more pronounced GI involvement or symptom perception in PD. © 2022 The Authors.  Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by motor and nonmotor manifestations.Recently, an α‐synuclein origin site and connectome (SOC) model has been suggested, dividing PD into brain‐first and body‐first subtypes.Dopamine transporter (DAT) imaging with single‐photon emission computerized tomography (SPECT) is an in vivo biomarker of nigrostriatal neuron loss. The correlation between the motor symptoms and the striatal DAT binding is well recognized; however, the relation between nonmotor symptoms and DAT binding has been investigated in only a few studies.We hypothesized that in early‐stage PD patients, less asymmetric DAT deficit is associated with more GISs.123I‐FP‐CIT SPECT because of parkinsonism or tremor in 2015–2019 at Helsinki and Turku University Hospitals . See the supplement for inclusion and exclusion criteria.Ninety PD patients were imaged using The study was approved by the Ethics Committee of the Turku University Hospital and was conducted according to the principles of the Declaration of Helsinki. All participants provided written informed consent.See the supplement for technical details of SPECT imaging. Specific DAT binding was calculated from striatal subregions  using region‐to‐occipital cortex ratio with BRASS software Table .12The limit for an abnormal scan was more than two standard deviations below the reference mean in any of the six analyzed regions.Mean putamen DAT binding was calculated for both sides as mean putamen = (anterior putamen SBR + posterior putamen SBR)/2.Mean putamen asymmetry index (AI) in DAT uptake was then calculated as AI = (putamenhighest − putamenlowest)/(putamenhighest + putamenlowest). AI > 0.05 was considered as significantly asymmetric reduction in DAT binding.Assessments are summarized in Table We used Rome III criteria for the identification of functional gastrointestinal disorders (FGIDs): IBS, FC, functional diarrhea, functional dyspepsia, and functional bloating.Based on the motor symptoms' AIs, 50 (55.6%) patients had predominantly symmetric, 20 (22.2%) predominantly right‐sided, and 20 (22.2%) predominantly left‐sided motor symptoms at the time of imaging. In many of the previous studies, the laterality has been analyzed based on motor symptoms, but we also utilized dopamine imaging data. The motor symptoms AI correlated with the imaging AI best for mean putamen Figure .All the analyses were performed using IBM SPSS Statistics version 25  patients had asymmetric and 18 (20.0%) symmetric reduction in DAT binding. The majority of the patients (90%) reported asymmetric and 10% symmetric onset of motor symptoms. Degree of asymmetry of mean putamen DAT binding showed no statistically significant association with any clinical measure  were significantly more common and Wexner constipation scores higher in patients with left‐predominant reduction Table .The aim of this study was to elucidate the association between nigrostriatal DAT binding asymmetry and GISs in PD. Falsifying our initial hypothesis, more symmetrical binding was not associated with increased GISs.The proportion of PD patients fulfilling the criteria for IBS  observed in this study is in line with previous findings in Finnish (24.3%) and Japanese (27.1%) populations.123I‐FP‐CIT binding ratios in the right caudate nucleus and mainly driven by gastrointestinal [Scales for Outcomes in Parkinson's Disease—Autonomic (SCOPA‐AUT) score] and cardiovascular dysfunction.Previous studies have suggested a relation between the laterality of dopaminergic neurodegeneration and nonmotor symptoms in PD. In contrast to our study, the study by Deursen and colleagues showed that autonomic symptoms were related to lower Psychosis has been associated with right‐predominant motor symptoms.The SOC model posits that α‐synuclein pathology is the core feature in PD pathogenesis. The anatomical location of the first pathogenic α‐synuclein is important, and the neural connectome also plays a crucial role in determining how pathological α‐synuclein propagates through the nervous system.Although our results did not confirm a relation between subjective GISs and stronger symmetry of dopaminergic neurodegeneration, our results do not necessarily argue against the SOC model. The GI tract is regulated by the local nervous system and the vagal nerve. Furthermore, the information spreads through the vagal nerve to the striatum but also wider in the central nervous system. Consequently, the correlation between subjective GISs and objective dysfunction has been far from optimal.Overall, patients' symptom experience is a combination of different mechanisms, and it cannot be directly inferred that patients with more severe subjective GISs have more gut pathology.123I‐FP‐CIT SPECT and not only by the distribution of motor symptoms. However, the definition of symmetrically reduced dopaminergic activity is artificial. We chose a previously used definition of AI value between −0.05 and 0.05, and it is possible that other cutoff values would produce different results.The main strength of this study is that the laterality of PD pathology was assessed using 123I‐FP‐CIT SPECT, and patients were followed to further minimize the probability of false PD diagnosis (the mean follow‐up time being 30 months).Another strength of this study is that the diagnosis of PD was confirmed using the 123I‐FP‐CIT SPECT imaging to confirm the diagnosis and leading to selection bias. These PD patients might thus differ from the general PD population in terms of the underlying etiologic factors, and results cannot necessarily be generalized to the entire PD population.Given that patients were sent to imaging for diagnosis, most of them had early‐stage symptoms without long use of dopaminergic medication or were drug‐naive patients. Nevertheless, the average time since motor symptom onset in our cohort was 29 months and, nonsignificantly, longer in symmetric 34 months) than in asymmetric (27.6 months) patients. This is longer than in previous imaging studies of RBD‐positive (17 months) and RBD‐negative  PD patients, and we cannot exclude that diminishing of asymmetry during disease progression influenced our results. months tOne limitation in our study is that the GISs are based only on questionnaires. No objective functional gastrointestinal investigations were carried out.In conclusion, GIS burden was not associated with the degree of symmetry of DAT defect but rather with left‐sided DAT decrease. Further studies using objective biomarkers to assess GI pathology and dysfunction are needed to establish whether left‐sided DAT deficit is related to more pronounced GI involvement or rather symptom perception in PD.K.M. received grants from the Finnish Parkinson Foundation, the Hospital District of Helsinki and Uusimaa, and the Maire Taponen Foundation; T.M. received grants from the Finnish Parkinson Foundation, Emil Aaltonen's Foundation, and the Finnish‐Norwegian Medical Foundation, Employment Helsinki University Hospital, Neuroinnovation Oy; E.J. received grants from the Finnish Parkinson Foundation; E.M.: none; R.L.: none; T.N.: none; M.E. received grants from Turku University Hospital (ERVA funds), the Finnish Parkinson Foundation, and The Finnish Medical Foundation; S.N. holds stock ownership in medically related fields; K.L.: none; E.P. received the Finnish Government Research grant; lecturer honorarium from Abbott, AbbVie, and NordicInfucare; and consulting fees from Boston Scientific, NordicInfu Care AB, and AbbVie. PI in Finland: International Adroit‐study (Abbott DBS Registry of Outcomes for Indications over Time). 2021–: organized by Abbott; J.J. received a lecturer honorarium from Lundbeck; T.N. received grants from the Turku University Hospital (VTR funds); T.I.: none; V.K. received grants from the Päivikki and Sakari Sohlberg Foundation; serves on the advisory boards of AbbVie and Nordic Infucare AB; and received honoraria from AbbVie, Nordic Infucare AB, Orion Pharma, and Adamant Health; F.S. has received grants from the Academy of Finland, the Hospital District of Helsinki and Uusimaa, OLVI‐Foundation, Konung Gustaf V:s och Drottning Victorias Frimurarestiftelse, The Wilhelm and Else Stockmann Foundation, The Emil Aaltonen Foundation, the Yrjö Jahnsson Foundation, Renishaw, and received honoraria from AbbVie, Orion, GE Healthcare, Merck, Teva, Bristol Myers Squibb, Sanofi, and Biogen.K.M.: execution, analysis, writing, and editing of the final version of the manuscript; T.M.: execution, analysis, writing, and editing of the final version of the manuscript; E.J.: execution and editing of the final version of the manuscript; E.M.: execution and editing of the final version of the manuscript; R.L.: execution and editing of the final version of the manuscript; T.N.: execution and editing of the final version of the manuscript; M.E.: execution and editing of the final version of the manuscript; S.N.: execution and editing of the final version of the manuscript; K.L.: execution and editing of the final version of the manuscript; E.P.: editing of the final version of the manuscript; J.J.: design, execution, and editing of the final version of the manuscript; T.N.: execution and editing of the final version of the manuscript; T.I.: analysis and editing of the final version of the manuscript; V.K.: design, execution, and editing of the final version of the manuscript; F.S.: design, execution, and editing of the final version of the manuscript.Figure S1. Scatterplot of motor symptoms AI and mean putamen AI correlation. The X‐axis shows mean putamen AI. The Y‐axis shows motor symptoms AI. Spearman correlation ρ = 0.745 (p < 0.001) Negative motor symptoms AI (based on MDS‐UPDRS III) means left sided motor symptoms and negative mean putamen AI means right sided defect. AI = asymmetry index.Click here for additional data file.Figure S2. Correlation between mean putamen AI and Wexner sum score. Scatterplot against asymmetry index for Wexner score. Spearman correlation ρ = 0.20 (p = 0.067). Also 95% confidence interval lines shown. Negative mean putamen AI means right sided defect. Abbreviations: AI = asymmetry index.Click here for additional data file.Table S1. Patients with FGIDs and without FGIDs, basic information.Click here for additional data file.Table S2. PD patients divided into groups based on the mean putamen asymmetry index.Click here for additional data file.Table S3. SBR valuesand Z‐scorein PD patients in putamen and nucleus caudatus.Click here for additional data file.Appendix S1. Supporting Information.Click here for additional data file.


Recent studies indicate that the administration of open-label placebos (OLP) can improve symptoms in various medical conditions. The primary aim of this 3-week randomized controlled trial was to examine the effects of OLP treatments on pain, functional disability, and mobility in patients with arthritic knee pain.n = 41) or no treatment . OLP treatments were accompanied by the verbal suggestion “to decrease pain”  or “to improve mood” . Pain and mood levels were monitored on 11-point Numeric Rating Scales (NRSs) in a patient diary, and global clinical improvement (CGI-I) was assessed at the end of the study. At baseline and after 21 days, patients filled in validated questionnaires to assess symptoms and functional disability of the knee (WOMAC), mental and physical quality of life (SF-36), state anxiety (STAI-state), perceived stress (PSQ-20), and self-efficacy (GSE). In addition, knee mobility , heart rate variability (HRV), and diurnal cortisol levels were evaluated before and after treatment.Sixty patients  were randomized to one of two OLP treatments , with no difference between the OLP-pain and the OLP-mood groups . OLP treatment also improved WOMAC pain , again with no difference between the two OLP groups . WOMAC function and stiffness, knee mobility, stress, state anxiety, quality of life, and self-efficacy did not change differently between groups.Evaluation of daily pain ratings indicated significant pain decrease in the OLP groups compared to NT (OLP treatment improved knee pain in elderly patients with symptomatic knee osteoarthritis (OA), while functional disability and mobility of the knee did not change. The content of the verbal suggestion was of minor importance. OLP administration may be considered as supportive analgesic treatment in elderly patients with symptomatic knee OA.https://www.drks.de/), DRKS00015191 (retrospectively registered).German Clinical Trials Register ( Osteoarthritis (OA) is a degenerative, primarily non-inflammatory joint disease with chronic course and represents the most common joint disease among adults . It is cIt has long been assumed that deception is necessary to evoke placebo effects. Accordingly, the deceptive administration of placebos is the primary subject of placebo research and is rather common in clinical practice –19. NoneThe psychological mechanisms underlying the effects of OLP administration are unknown. While the effects of deceptive placebo interventions are mediated in part by expectations raised by verbal suggestions, there is increasing evidence that conscious expectations are of limited importance for the effects of OLP . FurtherIn this randomized controlled trial, we investigated the effects of OLP administration in patients with symptomatic knee OA. In order to study the role of different verbal suggestions for the effects of OLP, we included two OLP interventions: one to “relieve pain” (“OLP-pain”) and one to “improve mood” (“OLP-mood”). The OLP-pain intervention was described as reducing pain and thereby improving health status, while the OLP-mood intervention was described as enhancing positive emotions and thereby improving health status. The rationale behind the mood-enhancing OLP intervention was based on previous studies showing that placebo interventions can improve mood , and thaThis is a randomized controlled trial with a three-group parallel design. A total of 60 participants were randomized to one of three groups using a 1:1:1 randomization rate. After the baseline measurement on the first study day, participants were randomly assigned to no treatment (NT), OLP to reduce pain (OLP-pain), or OLP to improve mood (OLP-mood).via advertisements in local newspapers and by laying out flyers in local medical practices. Patients were included when they were ≥18 years old, in a good general/nutritional condition and were diagnosed with OA of the knee (Kellgren II–III) at least 6 months prior to the onset of the study, as evidenced by a physician letter. In addition, participants had to provide sufficient knowledge of German to understand the questionnaires, had to be able to follow the study requirements and instructions, and had to provide written informed consent. The mean pain score at the target knee had to be at least 4 on a 0–10 Numeric Rating Scale (NRS), while pain in the non-target knee should not exceed a level of 3. Exclusion criteria comprised inflammatory joint disease; other pain conditions; knee injury or surgery within the previous 3 months or planned surgery during the study period; intra-articularly injected knee pain medication; use of opioid analgesics, glucocorticoids, topical pain treatment, or systemic treatments that could affect outcomes during the study; medications that affect the autonomic nervous system or neuroendocrine system; use of psychotropic drugs; known clinical depression and/or depression score >10 on the Hospital Anxiety and Depression Scale (HADS-D) (Patients with pre-diagnosed painful OA of the knee were recruited (HADS-D) ; drug abVolunteers who contacted the study center received information about the study procedure and the open-label placebo intervention and were screened for the inclusion and exclusion criteria during a telephone interview. Eligible patients who consented to participate were included in the study. Study participation comprised two examinations at the Institute of Medical Psychology, LMU Munich, with a time interval of 21 days. Prior to the first study visit participants received saliva tubes along with detailed instructions on how to collect and store saliva probes the day before study visits. At both study visits, participants completed standardized questionnaires, and a 5-min electrocardiogram (ECG) was performed to assess heart rate variability (HRV). At their first visit, patients were administered a paper-and-pencil diary to monitor pain, mood, and analgesic use each day of the study period. After performing the baseline assessments at the first study visit, participants received general information on the placebo effect, namely that the placebo effect is powerful, the body can automatically respond to taking placebo pills like Pavlov’s dogs who salivated when they heard a bell, a positive attitude helps but is not necessary, and taking the pills faithfully is critical . ParticiComputer-assisted randomization was performed by a person not involved in the experiments, who prepared sequentially numbered, sealed, and opaque randomization envelopes. Due to the open-label nature of the placebo treatment, group allocation was not blinded.After treatment allocation, the participants in the two OLP groups received a box with identical gelatin capsules filled with mannitol to be taken regularly twice daily (morning and evening) for a period of 21 days. The labels of the medication boxes differed between the two OLP groups, indicating either “pain relief” or “mood improvement.” The administration of the boxes was accompanied by verbal suggestions of the effects to be expected from the respective placebo treatment. In the OLP-pain group, patients were informed that the goal of placebo administration was to reduce pain and thereby positively influence health status. In the OLP-mood group, patients were informed that the goal of placebo administration was to improve mood and thereby positively influence health status .Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) is a standardized, disease-specific self-assessment instrument with verified psychometric quality criteria , which is a 36-item, validated patient-reported survey providing component scores for the mental and the physical health domains, with higher scores indicating better quality of life (Perceived Stress Questionnaire (PSQ-20). We report here the PSQ-20 overall score, ranging from 0 to 100, with higher values indicating higher burden , which estimates anxiety at the current moment  scale, a validated 10-item tool with good psychometric properties to measure the general, optimistic sense of perceived personal competence  scale, which uses a bipolar scaling from 1 (very much improved) to 7 (very much worse) (Patients assessed pain and mood levels each evening of the 21-day study period using a standardized paper-and-pencil diary. Average pain/mood during the day was rated on 11-point NRS from 0 (“no pain”/”worst mood”) to 10 (“unbearable pain”/”best mood”). Patients were further asked to note the use of acute pain medication in the patient diary. At baseline and after 21 days, patients completed the following questionnaires: the criteria , 38. It criteria . Quality of life . Perceivr burden , 42. Stat moment , 44. Thempetence , 46. Theh worse) .The neutral-zero method was used to assess the mobility of the target knee at baseline and after 3 weeks. It is a functional measurement that describes the possible active joint mobility of an individual joint with reference to the anatomical normal (“zero”) position. With the aid of a protractor, the respective active end positions of the joint for flexion and extension are documented .The electrocardiogram was recorded for 5 min using the MP 150 BIOPAC System  with AcqKnowledge 3.7.2 software. To increase reliability, the respiratory rate was standardized to 15 breaths per minute using a metronome . The ECG®, Sarstedt, Nümbrecht, Germany). Participants were instructed to chew the swabs for at least 60 s before storing it back into a tube, and to hand out the four salivary tubes to the study personnel at each examination day. Saliva samples were centrifuged at 2000 rpm at 4°C and stored at −20°C until analysis. Salivary cortisol concentration was assessed using cortisol saliva assay kits from IBL International GMBH (RE52611). All saliva samples were analyzed in duplicate following the manufacturer’s protocol. The area under the curve (AUC cortisol) was calculated for each examination day according to the trapezoid rule as outlined by Pruessner et al.  and range of mobility  from baseline to follow-up at 3 weeks. Secondary outcomes comprised the course of pain and mood ratings (NRS) and the need for analgesics during the 3-week study period, global clinical improvement (CGI-I) after 21 days, and pre–post changes in physical and mental quality of life (SF-36), perceived stress (PSQ-20), diurnal salivary cortisol (AUC cortisol), and HRV. We further evaluated pre–post changes in state anxiety (STAI-state) and self-efficacy (GSE).p < 0.05) to detect a moderate-to-large effect (d = 0.7), as reported by Kaptchuk et al. . We estimated that a total sample size of 60 would provide 80% power  and OLP-pain vs. OLP-mood groups (two-tailed). Cohen’s d effects sizes were calculated for parametric and non-parametric statistics  were averaged for each week. All pre–post changes of continuous outcomes fulfilled the one-way analysis of variance (ANOVA) assumptions and were subjected to ANOVAs, with “group”  as the between-subject factor. We primarily evaluated the contrasts between the NT and OLP groups (one-tailed) to test whether OLP has beneficial effects compared to NT. In an exploratory approach, we also evaluated the contrasts between the OLP-pain and OLP-mood groups (two-tailed). Pre–post changes in knee flexion and knee extension as well as post-treatment CGI-I scores were evaluated using Mann–Whitney atistics , with 0.atistics . StatistRecruitment took place between November 2016 and September 2017. A total of 61 out of 261 patients who contacted the study center were enrolled in the study; reasons for exclusion are summarized in t(56) = 2.282, p = 0.013, d = 0.64], while changes in the two OLP groups did not differ significantly from each other . The need for analgesics remained stable in the three treatment groups  = −0.462, p = 0.323, d = 0.13], nor between the two OLP groups .From week 1 to week 2, NRS mood ratings increased in the three groups to a similar extent and remained stable thereafter . Plannedt(57) = 1.835, p = 0.036, d = 0.55]. Changes in the two OLP groups did not differ from each other .The group means of the WOMAC subscores pain, stiffness, and function before and after the intervention as well as pre–post changes are shown in t(57) = 1.223, p = 0.226, d = 0.34; stiffness: t(57) = 0.505, p = 0.308, d = 0.14] or between the two OLP groups .The WOMAC subscores function and stiffness did not differ between the OLP and NT groups , nor between the OLP-pain and OLP-mood groups [t(57) = 0.013, p = 0.990, d = 0; t(57) = 1.444, p = 0.057, d = 0.4; OLP-pain vs. OLP-mood, t(57) = −0.011, p = 0.991, d = 0; State anxiety did not change differently between the OLP and the NT groups [In this randomized controlled trial, we examined the effects of OLP administration accompanied by two different verbal suggestions on symptomatic OA of the knee. Results revealed that OLP administration significantly reduced knee pain, regardless of whether patients were informed that the placebo would “decrease pain” or “improve mood.” In addition, clinical global impression was improved in the OLP groups compared to the NT group. Our results confirm previous findings that OLP treatment can improve chronic pain  and exteWhile the mean age of patients in the previous studies ranged between 40 and 60 years , 30, 58,We administered two OLP treatments differing by their declared goal, namely pain relief or mood improvement. Results show that neither pain or mood ratings nor any of the other outcomes differed between the two placebo groups. These results may partially be due to the small sample size of our study, with limited statistical power to detect differential effects between the two OLP interventions. For example, the respective effect sizes for the comparison of the WOMAC subscores stiffness and function scores were moderate at 0.4, suggesting that larger sample sizes would have been necessary to detect significant differences. However, with regard to pain, the effect sizes for the differences between the two OLP groups were generally small. Thus, our results suggest that OLP treatment was effective regardless of whether the explicit goal was to improve pain, or mood. Although we did not assess treatment expectations in our study, the finding that suggestion-specific effects did not occur indirectly supports previous findings that expectations play a limited role in OLP treatment. In a qualitative study, for example, patients receiving OLP treatment denied having positive expectations . FurtherRecent Bayesian brain models offer an alternative way to explain OLP effects, apart from positive expectations , 57, 62.d = 0.34). Regarding objective knee mobility, our findings are consistent with those of Kleine-Borgmann et al. (The question of whether OLP treatment can improve health-related quality of life remains unclear, as previous studies have shown mixed results. Disease-specific quality-of-life instruments appear to be better suited to demonstrate the beneficial effects of OLP , 28, 60 n et al. , who alsFinally, we explored whether the beneficial effects of OLP may be due to the reduction of stress and negative emotions. Study results consistently argue against such a view, as perceived stress, state anxiety and physiological stress parameters were not affected by OLP administration. Similarly, Kleine-Borgmann et al.  reportedSeveral possible limitations of the study have to be mentioned. The sample size of our study was rather small and some of the beneficial effects of OLP in patients with OA of the knee may have been missed due to the lack of statistical power. Nonetheless, the reported effect sizes provide a solid empirical basis to design future OLP studies in patients with symptomatic OA of the knee. Furthermore, the assessment of observer-reported outcomes was not blinded and the improvement in the CGI-I scale by OLP administration should be interpreted with caution. In addition, the study research team’s appreciative attention may have blurred some of the beneficial effects of OLP treatment, particularly on mood. Furthermore, our exclusion criteria were rather strict and many patients were excluded because of various illnesses or medication. This limits the external validity of our results, especially with respect to elderly people who frequently have multiple diseases. Finally, the short duration of OLP treatment does not allow to draw conclusions about the potential value of OLP treatment in clinical practice. However, Carvalho et al.  recentlyIn conclusion, our study is the first to provide evidence that elderly patients with symptomatic OA of the knee show pain relief by OLP treatment. Results lend support to the notion that concealment and deception are not necessary to evoke placebo effects in patients with chronic pain conditions. Future studies should address the role of synergistic and opposite verbal suggestions for OLP effects, as well as the long-term effects of OLP administration and its acceptability and feasibility in clinical practice.The datasets generated and/or analyzed during the current study are available from the corresponding author on request.The studies involving human participants were reviewed and approved by the Ethics Committee of the Medical Faculty, LMU Munich, Munich, Germany. The patients/participants provided their written informed consent to participate in this study.SS and KM designed the study. EO, SS, and AH carried out the experiment. EO, SS, AH, FR, and MM analyzed the raw data. SF and KM supervised the data analyses. EO, SS, and KM performed the statistical analyses. EO and KM wrote the first draft of 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.


Episodic angina-like retrosternal pain is a prevalent symptom for achalasia patients pre- and post-treatment. The cause of postoperative chest pain remains poorly understood. Moreover, there are no reports on their predictive value for chest pain in the long-term post-treatment. The effect of laparoscopic Heller myotomy (LHM) and fundoplication techniques (Dor vs. Toupet) is unclear.We analyzed a cohort of 129 achalasia cases treated with LHM and randomly assigned fundoplication technique. All the patients were diagnosed with achalasia by high-resolution manometry (HRM). Patients were followed up at 1-, 6-, 12-, and 24-month post-treatment. We implemented unadjusted and adjusted logistic regression analyses to evaluate the predictive significance of pre- and post-operative clinical factors.P = 0.006; adjusted model: OR = 26, 95% CI: 2.6–259.1, P = 0.005]. In type II achalasia, hypercontraction was also associated with an increased risk of chest pain . No significant differences were associated with age, type of achalasia, dysphagia, esophageal shape, and integrated relaxation pressure (IRP) with an increased risk of occasional postoperative chest pain. Also, there was no significant difference between fundoplication techniques or surgical approaches .Preoperative chest pain with every meal was associated with an increased risk of occasional postoperative chest pain [unadjusted model: odds ratio (OR) = 12, 95% CI: 2.2–63.9, Preoperative chest pain with every meal was associated with a higher risk of occasionally postoperative chest pain. Achalasia is a rare primary esophageal motor disorder characterized by the absence of swallow-induced relaxation of the lower esophageal sphincter and aperistalsis along the esophageal body –5. AlthoChest pain occurs in approximately 36–66% of pre- and 11–77.3% of post-achalasia treatment in different cohorts –20. MostPrior reports have indirectly assessed some of these mechanisms in prospective studies –20. HoweSince 2012, we have followed 129 achalasia patients who underwent LHM and randomly allocated fundoplication (Dor vs. Toupet). In this cohort, we monitored changes in clinical characteristics (incidence of symptoms) and diagnostic study findings (HRM) for over 8 years. Here, with these long-term assessments, we aimed to estimate the cumulative incidence of chest pain, accounting for multiple episodes during follow-up, at 48 months post-LHM. Moreover, assess the effect of preclinical and postoperative characteristics  on long-term chest pain.A cohort study was followed by a randomized controlled trial to compare Dor vs. Toupet fundoplication after LHM. We analyzed 129 achalasia cases. A full description of this cohort is available elsewhere . All theAll the recruited cases had a confirmed diagnosis of achalasia by barium esophagogram, upper endoscopy, and HRM. We analyzed adult patients (≥ 18 years or older) without prior history of Chagas disease, esophageal stricture, gastric or esophageal cancer, peptic stricture, other esophageal motility disorders, or previous surgical treatment. At baseline, we performed detailed interviews and clinical assessments to collect demographic data and clinical history of achalasia. Achalasia symptoms were tracked at baseline and follow-up with the following international standardized, validated questionnaires: (1) Eckardt for dysphagia, regurgitation, chest pain, and weight loss ; (2) GERBefore surgery, all the patients underwent an upper endoscopy, barium swallow, and HRM before and after surgery, and an upper gastrointestinal series and upper endoscopy were performed on all the patients. Postoperative assessments included upper endoscopy, pHmetry, HRM, and clinical evaluation of symptoms  conducted at 1-, 6-, 12-, 24-, and 48-month postoperatively.High-resolution manometry assessments were performed with a 360 high-resolution catheter with 36 channels . We considered vigorous achalasia with any distal amplitude contractions greater than 37 –31. A 24P-values less than or equal to 0.05 were considered significant.Descriptive statistic was performed, and categorical variables were compared using the chi-squared test or Fisher’s exact test. Continuous variables including age, BMI, disease evolution, questionnaires, neutrophil to lymphocyte ratio (NLR), pneumatic dilation sessions, esophageal dilation, basal lower esophageal sphincter (LES) pressure, IRP, and distal contractile integral analysis were performed using the Kruskal–Wallis one-way ANOVA on ranks. All the pairwise multiple comparison procedures were done by Dunn or Holm–Sidak method. Correlations among age, BMI, disease evolution, questionnaires, NLR, basal LES pressure, IRP, and distal contractile integral analysis were done using the Pearson correlation coefficient. Statistical analyses were performed using the Sigma Stat 14.5 program . Data are expressed as the median, range, and mean ± SD/SEM. We then plotted the incidence of chest pain frequency  at the different evaluations as shown in n = 21) and with chest pain , it was found that patients with pain had an Eckardt score , GERD-HRQL score , and EAT score  higher than patients without chest pain  compared to presurgery patients  had lower Eckardt score  vs. 45.5 ± 29.6 (n = 6); P = 0.044; n = 41).A 6 months after surgery, the patients without chest pain (n = 37) had lower Eckardt score . The number of patients with dysphagia and without chest pain was also lower  remained with a sustained reduction in the score of the questionnaires Eckardt score .A 24 months after surgery, the patients without chest pain .The chest pain with every meal decreased at 1-, 6-, 12-, and 24-month post-surgery compared with presurgery . Dysphagia disappeared at 1-, 6-, 12-, and 24-month post-surgery in 57.3, 45.1, 46.2, and 45.0% of patients, while all the patients had dysphagia before surgery . We did not find significant correlations between GERD-HRQL and EAT-10 scores, age, BMI, disease evolution, NLR, basal LES pressure, IRP, and distal contractile integral.We found positive correlation between the chest pain and Eckardt score  models at 12 months post-surgery. Results are shown in OR) = 12, 95% CI: 2.2–63.9, P = 0.006; adjusted model: OR = 26, 95% CI: 2.6–259.1; P = 0.005].Preoperative chest pain with every meal was associated with an increased risk of occasional postoperative chest pain [unadjusted model: odds ratio .Preoperative episodic angina-like retrosternal pain daily was associated with an increased risk of occasional postoperative chest pain .Preoperative occasional chest pain was associated with an increased risk of occasional postoperative chest pain . No significant differences were associated with age, type of achalasia, dysphagia, esophageal shape, and IRP with an increased risk of occasional postoperative chest pain. Also, there was no significant difference between fundoplication techniques or surgical approaches .In type II achalasia, hypercontraction was also associated with an increased risk of chest pain , BMI, GERD-HRQL, GERD pyrosis, EAT-10, Eckardt score, dysphagia, basal LES pressure, IRP, amplitude distal contractions, and distal contractile integral (DCI) on the variable chest pain. The regression model showed that the variables explained 89.32% of the variance from the chest pain variable. An ANOVA was used to test whether this value differed significantly from zero. The present sample showed that the effect was significantly different from zero, 2 = 0.89 –7.This study evaluated the long-term incidence of chest pain after a laparoscopic myotomy and fundoplication for achalasia. We built upon prior works identifying critical clinical factors associated with this symptom, pre- and post-surgical. However, we implemented a comprehensive approach by analyzing the risk for multiple symptom recurrence up to 24 months post-LHM. By this approach, preoperative pain frequency positively predicted postoperative episodic angina-like retrosternal pain persistence. We also found a positive correlation between chest pain and Eckardt score in each time evaluated. Notwithstanding our comprehensive approach, in our study, other clinical features with a significant association in prior works –20 were 9. This predictive factor was independent of age and sex. Especially, age independence is crucial since several reports describe an age-dependent relation to chest pain incidence  of individuals. Hence, our incidence estimations may be biased in this stratum. Nevertheless, our study contributes to long-term assessments evidencing trends described above, not previously reported.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.The studies involving human participants were reviewed and approved by the Ethics and Research Committee of the Salvador Zubirán National Institute of Medical Sciences and Nutrition. The patients/participants provided their written informed consent to participate in this study.HO-P, JP-F, SN-C, AP-O, and MR-M performed the analysis and interpretation of the data, responsible for the study conception and design, and wrote the manuscript. HO-P, JP-F, SN-C, JF-C, MN-P, AT-D, RA-S, FL-V, EC-A, and MV collected patient’s data from the clinical files, created the database, analyzed and interpreted the data, and wrote the manuscript. GT-V analyzed the data, wrote the manuscript, critically revised the manuscript for important intellectual content, and was responsible for the study conception and design. All authors contributed to the article and approved the submitted version.