Since little is known about chronic kidney disease (CKD) among people living with HIV/AIDS (PLWHA) in Sub-Saharan Africa, the prevalence and nature of CKD were assessed in Burundi through a multicenter cross-sectional study.Patients underwent assessments at baseline and 3 months later. Glomerular Filtration Rate (GFR) was estimated using abbreviated 4-variable Modification of Diet in Renal Diseases (MDRD) and Cockroft-Gault estimation methods. Patients were classified at month 3 into various CKD stages using the National Kidney Foundation (NKF) definition, which combines GFR and urinary abnormalities. Risk factors for presence of proteinuria (PRO) and aseptic leukocyturia (LEU) were further analyzed using multiple logistic regression.Median age of the patients in the study (N = 300) was 40 years, 70.3% were female and 71.7% were on highly active antiretroviral therapy. Using the MDRD method, CKD prevalence in patients was 45.7%, 30.2% of whom being classified as stage 1 according to the NKF classification, 13.5% as stage 2 and 2% as stage 3. No patient was classified as stage 4 or 5. Among CKD patients with urinary abnormality, PRO accounted for 6.1% and LEU for 18.4%. Significant associations were found between LEU and non-steroidal anti-inflammatory drug (NSAID) use, previous history of tuberculosis, low body mass index and female gender and between PRO and high viral load.Our study, using a very sensitive definition for CKD evaluation, suggests a potentially high prevalence of CKD among PLWHA in Burundi. Patients should be regularly monitored and preventative measures implemented, such as monitoring NSAID use and adjustment of drug dosages according to body weight. Urine dipsticks could be used as a screening tool to detect patients at risk of renal impairment. Since the era of highly active antiretroviral therapy (HAART), mortality and morbidity among HIV-infected patients in high-income countries have dramatically shifted from opportunistic infections (OI) to chronic conditions . Since 1In resource-limited countries, while OI still account for the majority of HIV-related mortality and morbidity, their incidence is likely to decline, paralleling the continued implementation of earlier and wider access to HAART. OI will be replaced by chronic diseases, including CKD, as a consequence of longer survival . PatientData on PLWHA renal function in SSA are scarce, despite being the area hardest hit by the pandemic. Data that is available on CKD prevalence in PLWHA ranges from 6% to 45%, although a variety of definitions have been used -11.In Burundi, CKD data are inexistent, both in the general population and among PLWHA. We assessed the prevalence of CKD among PLWHA in Burundi through a multicenter cross-sectional study. We also assessed risk factors related to CKD among PLWHA in order to draw recommendations in terms of monitoring.A multicenter cross-sectional survey was conducted between February 2008 and February 2009 in 4 outpatient HIV-clinics in Bujumbura, Burundi.1 positive adults above the age of 18 who attended the clinics for routine visits during the survey period were included, until the predefined objective of 300 patients (75 patients per site) was reached. The assumptions underlying the calculation of the sample size were that 250 000 persons were HIV positive in Burundi, at least 12% of whom having CKD, based on the literature reviewed at that time  [CG (ml/min) = {(140 - age) (weight)(1.18 if of African origin)}/serum creatinine] [The Glomerular Filtration Rate (GFR) was estimated by 2 methods: a) abbreviated 4-variable Modification of Diet in Renal Disease (MDRD) [GFRatinine] . Serum cCG < 60 ml/min or GFRMDRD < 60 ml/min/1.73 m2 and/or kidney damage defined as a urinary abnormality at any GFR level. In addition to proteinuria, which was the most evidence-based marker of kidney damage according to NKF, 2 other markers were included, leukocyturia and hematuria. Urinary abnormality was defined by isolated proteinuria ≥ 1+ or isolated hematuria ≥ 2+ or isolated leukocyturia ≥ 2+ or the association of hematuria ≥ 1+ with leukocyturia ≥ 1+ or proteinuria ≥ 1+. Patients with urine dipstick abnormalities as described above at baseline underwent a urine bacterial examination. If a urinary tract infection was diagnosed, the patient was prescribed an appropriate antibiotic and urine samples were again assessed by dipstick 10 days after the completion of treatment, in order to both confirm the disappearance of the urine infection and reassess urinary abnormalities. If leukocyturia persisted, the patient was screened for symptoms of active tuberculosis.The definition and classification of CKD were based on the National Kidney Foundation (NKF) guidelines . AccordiCG < 60 ml/min, GFRMDRD < 60 ml/min/1.73 m2, or if urinary abnormalities persisted at month 3 after the baseline assessment.Patients were classified as CKD if GFRIn addition, persistent abnormalities as highlighted by urine dipstick at month 3 were categorized into 5 groups (a-e): a) proteinuria (PRO) in case of either isolated proteinuria ≥ 3+ or proteinuria ≥ 1+ associated with hematuria ≥ 2+ or leukocyturia ≥ 2+; b) leukocyturia (LEU) in case of leukocyturia ≥ 2+, isolated or not, without proteinuria; c) hematuria (HEM) in case of isolated hematuria ≥ 2+; d) glycosuria (GLY) in case of normoglycemic glycosuria; e) any other combination of abnormalities  was classified as "other".Due to local constraints, it was not possible to perform ultrasonographic examination or renal biopsy in patients diagnosed with CKD.Stata version 8  was used for all statistical analyses. We provided descriptive analysis of the study population and GFR, using the 2 methods of measure, CG and MDRD. Prevalences of CKD were calculated together with their 95% confidence intervals, after checking the normality of their distribution. Lost to follow-up patients were considered as either being all affected by CKD or none being affected, to provide upper and lower estimates of CKD prevalence as part of the sensitivity analysis. As CKD is a mixture of multiple etiologies, we focused on the analysis of abnormalities as highlighted by the use of urine dipsticks. Patients with glycosuria, related to either pregnancy or diabetes mellitus, were excluded from the risk factor analysis, as were patients with known causes of CKD, namely diabetes and hypertension.Predictors of PRO and LEU were analyzed, using a univariable analysis and multivariable logistic regression model. Numerical variables were included as continuous variables after verifying their normality, otherwise they were used as categorized variables. Variables associated with PRO or LEU, with a p-value < 0.2 in univariate analysis, were included in a multivariable analysis. The most parsimonious final model was determined by using a stepwise method, while variables were also removed when statistical interactions with a biological explanation were present (e.g. between WHO stage and a history of tuberculosis).MDRD and GFRCG, we adjusted GFRCG for the body surface area (BSA), using the Dubois formula , p = 0.01). Pregnancy was not associated with LEU.Five patients with CKD from hypertension or diabetes were excluded for the purpose of the risk factor analysis. Results of univariable and multivariable analysis for risk factors of LEU are shown in Tables 10 copies/ml .Results from the risk factor analysis of PRO are shown in Tables The results of the sensitivity analysis were as follows: if loss to follow-up patients were all classified as CKD (according to the MDRD method), or as non-CKD, prevalence of CKD would have been 55.6% and 37% respectively.CG and GFRMDRD was 0.91. The Bland Altman method provided a mean difference of -1.7 ml/min/1.73 m2 between BSA adjusted GFRCG and GFRMDRD [95% CI -3.7 to -0.3]. The kappa index of agreement between the NKF stages classification, based on either GFRMDRD or GFRCG was 0.79.The Pearson's correlation coefficient between BSA adjusted GFRThe prevalence of CKD among this population of PLWHA in Burundi accounted for nearly half of the sample: 45.7% using the MDRD method and 46.5% using the CG method. LEU was more frequently identified than PRO, accounting for 18.4% and 6.1%, respectively.CG below 60 ml/min or a combination of definitions assessing the presence of proteinuria together or not with the GFR [This prevalence of CKD is one of the highest ever found among both resource-rich and resource-limited countries ,11,18,19MDRD < 60 ml/min/1.73 m2) represented 2% of our sample, using the MDRD estimation and 4.9% using the CG estimation. Quite similar rates were found in Kenya and Spain, 4.8% [MDRD < 90 ml/min/1.73 m2 represented 15.5% in our sample. Overton et al. reported a much higher prevalence of 43% in the United States, but hypertensive patients were included in their sample and constituted 33% of their population [CG < 60 ml/min was 12% at baseline and decreased with HAART to 4%, after 24 months of follow up [CG < 60 ml/min and could be linked to the fact that the majority of our patients (71.7%) were on HAART. Indeed, Kalayjian et al. reported significant GFR improvement following HAART prescription, supporting the hypothesis that kidney inflammation is secondary to immune activation [Patients at NKF stage 3  possibly reflects sequelae of the urological extension of tuberculosis which is common but underdiagnosed . In our  sterile . The aut2 increment). In Burundi, adjusting dosages to body weight is not always possible. Consequently, patients with a low BMI are exposed to a greater concentration of drugs and therefore to acute tubular necrosis, with sequellar interstitial damage (e.g. with aminoglycosides). In our results, the use of aminoglycosides was associated with the presence of LEU in univariable analysis, but due certainly to a lack of power, the association did not remain in the multivariable analysis. Association between low BMI and renal impairment was also reported in Nigeria. This was explained as being due to an advanced renal disease [In our sample, an increase in BMI was negatively associated with the presence of LEU . Prevalence of HIVAN at the time of the study was estimated at between 3.5% and 12%, the highest rates coming from autopsy-based estimations . HoweverMDRD and GFRCG were good. Buitrago et al found a moderate level of agreement (kappa index of 0.55) but focused on agreement for CKD at stage 3, which was underrepresented in our sample [In our sample, both correlation and agreement between GFRr sample . The MDRr sample ,23.We acknowledge several limitations to our study, due to the challenges of performing specialized examinations in Burundi. The great difficulty in performing ultrasound measurements and renal biopsies prevented precise diagnosis of patients diagnosed with GFR and/or urine dipstick abnormalities. We therefore used urinary abnormality as a tool to categorize patients and discussed possible diagnosis linked to them. Among female patients, chronic pyelonephritis or asymptomatic bacterial urinary tract infections could have been underdiagnosed due to a low quality of bacteriological examination, especially for those on cotrimoxazole. This could have led to an overestimation of CKD prevalence and could partly explain the association between female gender and LEU. Tuberculosis may also have been underdiagnosed, but none of the patients presented with clinical signs of active disease. The presence of leukocyturia and hematuria might also be related to genito-urinary diseases other than tuberculosis or urinary tract infections. Underdiagnosis of these infections might have led to an overestimation of CKD prevalence in our sample. The baseline kidney status of the non-HIV population is largely unknown in Burundi and we cannot attribute kidney function abnormalities to HIV-related factors with certitude. Similarly, the Dubois equation was used although the relevance of this equation in this population is unknown. Despite these biases, we believe the results of this study are important in helping raise awareness of CKD among PLWHA in this context.Whereas previous studies mainly focused on HIVAN, there is now a need to shift towards a more comprehensive review of all the potential risk factors associated with CKD. HIV is a chronic disease and patients are now exposed to a range of non HIV-specific kidney risk factors, such as arteriosclerosis, hypertension or diabetes mellitus. In addition, PLWHA are more likely to experience kidney damage, due to a higher susceptibility to renal infections including tuberculosis, to longer and more frequent exposure to multiple drugs, HIV-related or not, and finally due to inflammation. Thus, diagnosing HIV earlier could lead to earlier HAART prescription, as recently recommended by the WHO . This coBMI: Body Mass Index; BSA: Body Surface Area; CG: Cockroft-Gault; CI: Confidence Interval; CKD: Chronic Kidney Disease; GFR: Glomerular Filtration Rate; GLY: Glycemia; HAART: Highly Active Antiretroviral Therapy; HEM: Hematuria; HIV: Human Immunodeficiency Virus; LEU: Leukocyturia; MDRD: Modification of Diet in Renal Disease; NKF: National Kidney Foundation; NSAID: Non Steroid Anti-Inflammatory Drug; OI: Opportunistic Infections; OR: Odds Ratio; PLWHA: people living with HIV/AIDS; PRO: Proteinuria; SSA: Sub-Saharan Africa.The authors declare that they have no competing interests.JC, HI, TN and OB contributed to conceptualizing and designing the study. JC, BN, TN, LM, DS, EB, JN participated in the coordination and implementation of the study. BN performed the data collection and EN supervised the data capture. JC and EN performed the data analyses. All authors have been involved in drafting the manuscript.All authors read and approved the final manuscript.The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1471-2369/12/40/prepub


Intrauterine growth restriction plays a powerful role in influencing later susceptibility to certain chronic diseases, such as hypertension. Endothelial dysfunction and arterial stiffness are early events in the development of cardiovascular diseases (CVDs). We have studied vascular compliance in small for gestational age (SGA) children/adolescents in comparison with that in appropriate for gestational age (AGA) subjects.We monitored blood pressure, vascular resistance and compliance in 82 children–adolescents , by means of pulse wave analysis (CR 2000 HDI) at the radial level, before and after 3 min of ischemic stress at the brachial level.In the children/adolescents born SGA we found a significant increase in systolic and diastolic blood pressure and vascular resistance in the basal condition; the large and small vessels were stiffer. After ischemia we observed an increased vascular response in the SGA children/adolescents: there was a great diminution of systolic and diastolic blood pressure and a larger increase of the elasticity of the conduit and resistance vessels.These data show that the SGA group presented some early signs of arterial wall functional disorders. More pediatric data are needed for the evaluation by non-invasive techniques of vascular function in children–adolescents at risk of CVD. An extensive body of research has shown that birth weight is related to adverse outcomes, such as hypertension, risk of coronary heart disease and type 2 diabetes, with smaller babies having a greater risk with age –4, with Reduced arterial elasticity, measured also in terms of vascular compliance, stiffness, or distensibility, is an early sign of vascular damage and can be used as a surrogate marker of arterial function , 17. AssVascular endothelial dysfunction is a key event in the development of diseases associated with birth weight , and a pTo explore vascular function in a very early phase of life (children or adolescents) we studied the vascular compliance of two groups of subjects divided according to birth weight. We checked arterial compliance before and after ischemic stimuli in a group of SMA children/adolescents monitoring conduit compliance and vessel resistance by radial pulse wave analysis. We also examined induced vascular reactivity after a standardized ischemic stimulus.From April 2008 to April 2009, we studied 82 children and adolescents . They were divided into two groups according to birth weight and gestational age , 27. IUGWe enrolled 52 Italian children/adolescents with a gestational age of 37–38 weeks into the SGA/IUGR group ; these children had been followed up in a regular clinical program. The average birth weight was 1,684 ± 520 g, the average head circumference at birth was 31.8 ± 1.8 cm, and the average age at the time of examination was 12.40 ± 2.47 years. The control group comprised 30 children/adolescents  born full term and with the appropriate weight for gestational age (AGA); the average age at the time of examination was 12.27 ± 1.74 years. The subjects of both groups were nonobese, and they were all at Tanner developmental stage 2.Blood pressure measurements were obtained from the right arm of each subject in a supine position. The proper cuff size was ensured by arm measurements. Systolic and diastolic blood pressures  were determined by automated oscillometric monitors . The clinical characteristics of the 52 SGA children/adolescents and the 30 age- and sex-matched AGA children/adolescents of the control group are summarized in Table Exclusion criteria were known congenital or acquired cardiovascular, hepatic, renal, or brain diseases, genetic syndromes, and chronic gastrointestinal diseases, such as celiac, metabolic, or endocrine disorders.The Institutional Local Ethical Committee of the Siena University Hospital  approved the study. Informed consent was obtained from older children and from both parents of all children after a full explanation of the study prior to enrolment.The subjects were studied between 1500 hours and 1800 hours; after 15 min of rest in a quiet, temperature-controlled room, with the subject in a recumbent position, BP measurement and pulse wave analysis (PWA) were performed three times at 5-min intervals. We then provoked an ischemic stimulus with a cuff placed on the brachial segment of the forearm inflated to a pressure exceeding the systolic arterial blood pressure so that the radial homolateral oscillometric curve disappeared for exactly 3 min. The BP measurement and PWA were repeated four times at 5-min intervals.Diastolic pulse contour analysis uses a modified Windkessel model to derive information on proximal and distal arteries by analyzing the diastolic portion of the pressure pulse contour; we measured the arterial waveform in the nondominant arm with a cardiovascular profiling instrument . Briefly, the tonometer was applied to the patient’s radial artery at the wrist overlying the radial bony prominence. The subject’s arm was supported by a wrist stabilizer for optimal positioning and minimal movement during the measurements. The cuff for BP measurement was placed on the contralateral arm and inflated concurrently with the pulse waveform recording for calibration; a 30-s interval of analogue waveforms was digitized at 200 samples/s, and a beat marking algorithm was determined the beginning of systole, peak systole, onset of diastole, and end of diastole for all beats in the 30-s measurement period. The elasticity indices of the arteries (C1 and C2) were quantified during the diastolic portion of the heart cycle (mean recording time 30 s). According to the modified Windkessel model of circulation, C1 is a marker of large artery elasticity and C2 is a marker of small artery elasticity. Heart rate, mean arterial pressure (MAP), and stroke volume were also calculated from the radial pressure waveform using HDI/Pulse Wave CR-2000 software. These hemodynamic parameters (i.e. MAP and stroke volume) are used in multivariate algorithms for determining C1 and C2. The full method has already been validated and described in detail in adult patients ; howeverAll variables were tested for normal distribution by the Kolmogorov–Smirnov test and for variance homogeneity by the Levene test. The variables are expressed as average values and SD or as absolute frequency.t test or proportions test. The one-way analysis of variance, with the Dunn post hoc test for multiple comparisons when necessary, was used to compare the determinations of each group (AGA and SGA). A P value of <0.05 was considered to be statistically significant. The statistical analysis was performed using SPSS statistical software ver. 14.0 .The AGA and SGA groups were compared under basal conditions using the unpaired A total of 82 children/adolescents were studied: 30 AGA  and 52 SGA . Table t test, P < 0.01, with a difference of + 7.6 mm Hg) and DBP ; significant negative differences were highlighted in C1  and in C2 . There were also significant difference in vascular resistances (VR) . However, there was no statistical difference between the two groups for the pulse pressure (PP) variable . , DBP (P = 0.149), and pulse pressure (PP) (P = 0.191) in the AGA group. The multiple comparisons in the AGA group showed a significant difference for the variables C1 (P = 0.949), C2 (P = 0.348), and vascular resistance (P = 0.949). In the SGA group, the change in SBP (P = 0.096), DBP (P = 0.444), PP (P = 0.075), and C2 (P = 0.105) following application of the ischemic stimulus was not significant; however, there was a significant increase of C1 (P < 0.01) and a significant reduction of vascular resistance (VR) (P < 0.001). In particular, we found a significant increase (+1.73 mmHg) between basal time and the last time for C1 , and a significant reduction between basal time and each time of post-ischemic determination for VR (−117 dyne/s × cm-5) , DBP  and VR (−117 in SGA vs. −116 in AGA). We also observed a greater increase in the indexes of macrovascular compliance [+1.73 vs. +0.4 (ml/mm Hg × 10) in SGA vs. AGA groups] and microvascular elasticity [+0.82 vs. +0.35 (in ml/mm Hg × 100) in SGA vs. AGA groups]. The percentage changes from pre- to post-ischemia in the SGA group are shown in Fig. Knowledge of the characteristics of the vascular tree in IUGR infants, children, and young adults can help clarify the underlying mechanisms that are at the origin of hypertension in this population at increased risk of CVD in adulthood.In the SGA group we observed an increase in systolic, pulse, and diastolic blood pressure and in vascular resistances; the elasticity of the large and small vessels was lower in the SGA than in the AGA group. These data are in line with those reported by other authors , 26–29 w−5) and an increase in the C1 (+0.35 ml/mm Hg × 10) and C2 (+0.35 ml/mm Hg × 100). Following the same stress in the SGA group, we observed a more lively vasodilator response that was characterized by a greater decrease in SBP (−4.1 mm Hg), DBP (−1.53 mm Hg), PP (−2.86 mm Hg), and VR (−117 dyne/s × cm−5). We also observed a greater increase in the indexes of macrovascular compliance (C1 + 1.73 ml/mm Hg × 10) and microvascular elasticity (C2 + 0.82 ml/mm Hg × 100). These data support the hypothesis that in the SGA group the response induced by ischemic stress is greater, which could indicate that endothelial cells are chronically overstimulated to supply organs and tissues. This pathophysiological condition could not only increase oxidative stress on the vascular tree, thereby favoring progressive early damage to the vascular wall, for example by increasing stiffness in large and small arteries, but it could also explain the early appearance of hypertensive disease with the manifestation of endothelial dysfunction due to decreased synthesis and release of NO and other vasorelaxant substances. Mechanical forces, comprising both unidirectional laminar and oscillatory shear, are increasingly being recognized as important inducers of vascular NO and generators of reactive oxidative species (ROS). On the other hand, oscillatory shear is linked to increased ROS production with consequent oxidative damage, as occurs in hypertension. As recently reviewed, shear stress alone potently stimulates the release of vasorelaxant mediators, such as NO, enhances endothelial survival, and counters cell adhesion and thrombosis [When we provoked a standardized ischemic stress at the brachial artery of subjects in the AGA group, we observed a decrease in the SBP (−2.1 mm Hg), DBP (−3.4 mm Hg), PP (−2.5 mm Hg), and VR  in pediatric patients is limited; methods such as Doppler ultrasound are strictly dependent on highly trained personnel, and the few studies performed to date have involved relatively few subjects , 37. HowIn conclusion, we found a raised SBP and a reduced vascular elasticity under basal conditions in SGA children/adolescents; after the application of ischemic stress, the large and small vessels of these children/adolescents manifested a stronger vasodilation than those of AGA subjects. However, further studies with more subjects are required so that the prognostic value, relative to established predictors of risk, may be fully defined, especially in the pediatric population. Moreover we want to stress that the applanation tonometry method is absolutely not invasive and would appear to be particularly suitable for the pediatric/adolescent patient population, for which we need to have simple techniques that are non-invasive so as to increase the compliance of families and healthy children/adolescents to prevent cardiovascular disease .


ABPM was carried out in all patients. In CKD group, eGFR was 35.3 ± 2.8 ml/min. The mean 24-hour systolic and diastolic blood pressure (BP) was similar in both groups. AASI was significantly higher in CKD group , positively correlated to age  and pulse pressure  and negatively correlated to nocturnal BP fall . These findings indicate the presence of stiffer vessels in CKD hypertensive patients.Ambulatory arterial stiffness index (AASI) is a parameter obtained from ambulatory blood pressure monitoring (ABPM) that correlates with clinical endpoints. The aim of this study was to compare AASI in nondiabetic hypertensive patients with and without chronic kidney disease (CKD). Subjects with systemic arterial hypertension (SAH,  Epidemiological and observational studies indicate hypertension as a major cause of chronic kidney disease (CKD) . In factVascular changes are commonly observed in CKD patients, including reduced arterial elasticity observed in patients with end-stage renal disease , 9. FibrIt has already been reported that AASI presents good correlation with target organ damage and glomerular filtration rate (GFR) in essential hypertension –20. MoreA case-control study involving 60 consecutive patients with primary hypertension was carried out in our institution. Thirty patients were recruited from the CKD outpatient clinic. Hypertensive patients with CKD, aged 40 to 75 years and estimated glomerular filtration rate (eGFR) <60 mL/min by the Modification of Diet in Renal Disease (MDRD) equation , were inOffice blood pressure was obtained using an electronic device  and an appropriate sized cuff. Patients were seated for 30 minutes before measurement and refrained from smoking and caffeine ingestion in this period of time. Three readings, one minute apart, were done, and the average of these measurements was defined as the patient clinic blood pressure. The patients underwent 24-hour ABPM in nondominant arm with SpaceLabs 90207 monitor , validated by the British Hypertension Society and the Association for the Advancement of Medical Instrumentation protocol [ −1.154 × age−0.203. C-reactive protein  and morning urinary spot albumin and creatinine  were also measured. The lower detection limit for C-reactive protein was 0.20 mg/L. Values for microalbuminuria were considered normal up to 30 mg/g creatinine. Fasting venous blood was collected from participants to measure total cholesterol, triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), glucose, creatinine (enzymatic method), and uric acid. The low-density lipoprotein cholesterol (LDL-C) level was calculated by the Friedewald formula (8). eGFR was assessed by modified MDRD equation: eGFR = 0.741 × 175 × Crt-test were used to compare proportions and means, respectively. Pearson's correlation coefficients were used to explore associations between examined continuous variables with parametric distribution. Statistical significance was determined by α-level of 0.05 on two-sided tests.Data are presented as mean ± standard error of mean (SEM). For database management and statistical analyses, we used GraphPad Prism software, version 5.0 . Chi-squared test (for 2 × 3 tables) or Fisher's exact test (for 2 × 2 tables) and Student's Baseline clinical characteristics did not differ between the groups. As expected, hemoglobin was significantly lower and serum creatinine and uric acid were significantly higher in CKD group . Mean eGP = 0.0398) to obtain blood pressure control. When CKD was compared to SAH group concerning antihypertensive treatment, there was no significant difference for diuretics (60% versus 70%), angiotensin converting enzyme inhibitors/angiotensin receptor blockers (86% versus 77%) and beta blockers (40% versus 37%). However, use of calcium channel antagonists was significantly more common in CKD patients .The mean office and ambulatory blood pressure readings were similar in both groups , althougP = 0.0588). There were 40% of dipper patients, 50% of nondipper, and 10% of reverse dipper in SAH group. On the other hand, CKD group presented 30% of dipping pattern, 40% nondipping, and 30% reverse dipping (P = 0.20).The mean nocturnal systolic blood pressure fall was lower than 10% in both groups . Correlation tests showed that AASI was positively related to age , pulse pressure  and inversely related to nocturnal blood pressure fall   . AASI di = 0.03) .The results of our study demonstrate that hypertensive patients with CKD presented a higher AASI when compared to those with normal renal function. Supporting the concept that AASI is a marker of arterial stiffness, Li et al. described its correlation with pulse wave velocity, central and peripheral augmentation indexes . MoreoveSome authors have studied the relationship between AASI and renal function among hypertensive patients. Ratto et al. showed that AASI was positively related to urinary albumin excretion and negatively related to estimated creatinine clearance in a population of 168 patients with recently diagnosed hypertension and without drug treatment . Mulè etAgeing is an important factor for arterial stiffening. Elderly people are predisposed to lose arterial elastic laminae and increase collagen deposits in vascular wall , 31. ThiPulse pressure and nocturnal blood pressure fall are two parameters from ABPM that correlate with arterial stiffness , 35. LekThe present study has limitations considering the small sample size. Moreover, it was not prospective and not focused on clinical outcomes. However, our data strongly implies the value of AASI as a noninvasive tool for hemodynamic evaluation of CKD patient and reinforces the role of ABPM in hypertensive patients with renal dysfunction. Increased AASI might be one of the pathophysiological changes observed in CKD patients before the progression to end stage renal disease. More studies are needed to support the clinical usefulness of this parameter, but we propose that the software for ABPM analysis should include AASI value as a marker of cardiovascular risk assessment in the near future.


High resting heart rate (HR) is associated with increased cardiovascular risk in general populations, possibly due to elevated blood pressure (BP) or sympathetic over-activity. We studied the association of resting HR with cardiovascular function, and examined whether the hemodynamics remained similar during passive head-up tilt.Hemodynamics were recorded using whole-body impedance cardiography and continuous radial pulse wave analysis in 522 subjects  without medication influencing HR or BP, or diagnosed diabetes, coronary artery, renal, peripheral arterial, or cerebrovascular disease. Correlations were calculated, and results analysed according to resting HR tertiles.Higher resting HR was associated with elevated systolic and diastolic BP, lower stroke volume but higher cardiac output and work, and lower systemic vascular resistance, both supine and upright . Subjects with higher HR also showed lower supine and upright aortic pulse pressure and augmentation index, and increased resting pulse wave velocity (p < 0.001). Upright stroke volume decreased less in subjects with highest resting HR (p < 0.05), and cardiac output decreased less in subjects with lowest resting HR (p < 0.009), but clear hemodynamic differences between the tertiles persisted both supine and upright.Supine and upright hemodynamic profile associated with higher resting HR is characterized by higher cardiac output and lower systemic vascular resistance. Higher resting HR was associated with reduced central wave reflection, in spite of elevated BP and arterial stiffness. The increased cardiac workload, higher BP and arterial stiffness, may explain why higher HR is associated with less favourable prognosis in populations.NCT01742702ClinicalTrials.gov,  Measurement of heart rate (HR) is an easily available cardiovascular phenotype in clinical practice. Increased resting HR is associated with higher cardiovascular mortality and morbidity in general populations-5, even The mechanisms linking elevated HR with cardiovascular pathology and pathophysiology are not well understood. The association has been assumed to be a consequence of sympathetic over-activity,16. In aOn the other hand, there is a significant negative association between HR and central BP and central wave reflection. AugmentTaken together, even though higher HR at rest is associated with lower central wave reflection which is considered to be beneficial, it is associated with less favourable prognosis in observational studies,5,25,26.All study subjects participated in an on-going study, in which hemodynamics are noninvasively recorded from voluntary subjects . The ethics committee of the Tampere University Hospital approved the study protocol and patients gave an informed consent, as stipulated in the Declaration of Helsinki. An announcement for the recruitment of subjects was distributed at the University of Tampere, Tampere University Hospital, several occupational health care organizations, Varala Sports Institute, and two announcements were published in a local newspaper. The subjects who responded were successively recruited in the order that they contacted the research nurse. In November 2012 a total number of 830 subjects had been recruited to the study.2-sympathomimetics, α-adrenoceptor agonists, varenicline, or the weight-reducing agent sibutramine.In present investigation, those subjects with a history of coronary artery disease, diabetes mellitus, peripheral arterial or cerebrovascular disease, valvular regurgitation or stenosis, long QT syndrome, chronic renal insufficiency, hemochromatosis, or medication for hypertension were excluded. Also, subjects with regular medication influencing HR or BP were excluded, i.e. subjects using anti-arrhythmic agents, long-acting βAltogether 522 subjects  with technically successful hemodynamic recordings were included in the present study. The majority of subjects were without concurrent diseases or medications  per week. Physical exercise frequency was interviewed, and was expressed as the number of bouts of physical activity per week that lasted for at least 30 min each time and caused sweating or shortness of breath.Venous blood samples were drawn after ~12 hours of fasting. Plasma sodium, potassium, glucose, creatinine, cystatin C, C-reactive protein (CRP), and total, high-density (HDL) and low-density lipoprotein (LDL) cholesterol concentrations were determined using Cobas Integra 700/800 , or Cobas 6000, module c501 , and white blood cell count and haematocrit using ADVIA 120 or 2120 analyzers . Glomerular filtration rate was estimated using the Rule formula, since tHemodynamics recordings were carried out in a quiet, temperature-controlled laboratory by a research nurse. The subjects were instructed to refrain from caffeine-containing products, smoking, and heavy meals for at least 4 h, and from alcohol for at least 24 h prior to the investigation. Before the actual measurement the subjects were resting supine for approximately 10 min, during which period electrodes for impedance cardiography were placed on the body surface, a tonometric sensor for pulse wave analysis was fixed to the left wrist on the radial pulsation, and a brachial cuff for BP calibration was placed to the right upper arm. Then hemodynamic variables were continuously captured in a beat-to-beat fashion for 5 min in supine position and for 5 min during passive head-up tilt to 60 degrees. Mean values of each measured minute of the experiment were calculated and used in statistical analyses.R, JR Medical Ltd, Tallinn, Estonia), which records the changes in body electrical impedance during cardiac cycles, was used to determine beat-to-beat HR, stroke index , cardiac index , and PWV (m/s)[2) was calculated by formula 0.0143*(MAP–PAOP)*cardiac index, which has been derived from the equation published by Gorlin et al.[2O, volume to density of blood (kg/L), and centimetre to metre. Systemic vascular resistance index  was calculated from the signal of the tonometric BP sensor and cardiac index measured by CircMonR.A whole-body impedance cardiography device (CircMonWV (m/s)-31. Leftn et al.. MAP is impedance*0.696) + 0.864)[R are in good agreement with the values measured by the thermodilution method[To calculate the PWV, the CircMon software measures the time difference between the onset of the decrease in impedance in the whole-body impedance signal and the popliteal artery signal. From the time difference and the distance between the electrodes, PWV can be determined. As the whole-body impedance cardiography slightly overestimates PWV when compared with Doppler ultrasound method, a validated equation was utilized to calculate values that correspond to the ultrasound method (PWV = (PWV+ 0.864). PWV was+ 0.864). A detai+ 0.864). PWV was+ 0.864). The carn method, and then method,35.Radial BP and pulse wave form were continuously determined by the use of an automatic tonometric sensor , which was fixed on the radial pulse with a wrist band. The extended left arm was lying on a stable bracket at the level of the heart, whether supine or upright. Radial BP signal was calibrated by brachial BP measurement at the onset of the recording. Continuous aortic BP was derived with the SphygmoCor monitoring system  using the previously validated generalized transfer function. From thTo evaluate the accuracy of stroke volume determination with impedance cardiography during head-up tilt, echocardiography was performed by a cardiologist (author E.I.) to a subset of subjects (n = 16) during an extra visit. The 3D echocardiography  was performed simultaneously with beat-to-beat impedance cardiography recordings during head-up tilt to 60 degrees. Mean stroke volume from 7 consecutive heart beats (6 before and 1 after echocardiography) was calculated from impedance cardiography recordings to cover approximately one respiratory cycle (~6 seconds).For the statistical analyses, the study population was divided into tertiles according to mean resting HR, determined as an average HR of the last 3 min during the 5-min measurement period in supine position. Analysis of variances for repeated measures was applied to study the differences in the hemodynamic variables BP, stroke index, cardiac index, left cardiac work index, systemic vascular resistance index, AIx, and PWV between the HR tertile groups during rest and head-up tilt. For post hoc testing Tukey HSD test was performed for homogenous, and Tamhane’s T2 test for nonhomogeneous variables. In adjusted analysis of variances for repeated measures, the variables sex, age, body mass index, smoking in pack years, haematocrit, leukocyte count, CRP, creatinine, cystatin C, total cholesterol, triglycerides, HDL cholesterol, fasting plasma glucose, and mean radial arterial pressure at rest were used as covariates.2 test, and differences of numerical variables among HR tertiles were studied using analysis of variances. Variable values are given as means and 95% confidence intervals (CI). Natural logarithms of CRP and triglyceride concentrations were used in analyses to normalize their distributions. P-values <0.05 were considered statistically significant. The analyses were performed using SPSS Statistics 17.0 for Windows software .Pearson’s correlation coefficients were calculated, as appropriate, and possible differences in stroke volume determined using impedance cardiography and 3D echocardiography were tested using Student’s T-test. Distributions of categorical variables among resting HR tertiles were tested using χThe characteristics of the study population according to the HR tertiles at rest, with average values of 54, 62 and 75 beats/min in the 1st, 2nd and 3rd tertile, respectively, are shown in Table In the entire study population HR at rest showed a moderate association with resting radial systolic BP  and diastolic BP . In tertile 3 radial systolic and diastolic BPs were higher than in other tertiles, in both supine position and during head-up tilt  or upright positions (p = 0.452). However, supine aortic diastolic BP was higher in tertile 3 than tertiles 1 and 2 . Upright aortic diastolic BP was higher in tertile 3 than tertile 1 (p < 0.001).All HR tertiles showed a corresponding upright chronotropic effect , and the clear differences in HR between the tertiles persisted during the head-up tilt Figure A. The me2, CI: 9.7 to 11.2) , than in the 1st , and 2nd tertiles  (unadjusted and adjusted p < 0.001). Upright stroke index was lower in tertiles 2 and 3 than in tertile 1 (p = 0.002).Supine stroke index showed a significant negative correlation with HR , and in tertile 3 supine stroke index was lower than in other tertiles , and 3rd tertiles , than in the 1st tertile  (p < 0.034), but in adjusted analyses the difference remained significant only between the 1st and 3rd tertiles (p < 0.009). Importantly, the clear differences in cardiac index and left cardiac work index between the HR tertiles persisted in the upright position .In spite of the above negative correlation between stroke index and HR, supine cardiac index and also left cardiac work index were highest in tertile 3, and were also higher in tertile 2 than tertile 1 , so that AIx was mathematically reduced by 2.5%-units for every 10 beats/min increase in HR. Supine aortic pulse pressure was highest in the 1st HR tertile Figure A, while Arterial stiffness was evaluated by measuring resting PWV, the mean value of which in the whole study population was 8.5 m/s (CI: 8.3 to 8.7). HR was notably correlated with PWV . PWV was significantly higher in tertiles 2 and 3 than in tertile 1  and by echocardiography 67 ml CI: 59 to 75) , while there was no relation between HR and age. Previously, resting HR has been reported to be 2–7 beats/min higher in female than male subjects, while the effect of age on resting HR has been minor,39,51. IWhen measuring the human hemodynamics noninvasively, many of the variables are calculations or derivatives, and most of the calculations include HR in the procedure. The formulas used here have been found to be reliable-32,54, bWe found that the hemodynamic profile associated with higher resting HR was characterized by higher cardiac output, higher cardiac workload, and lower systemic vascular resistance. The hemodynamic features of the distinct HR tertile groups persisted during the head-up tilt. Higher resting HR was also associated with lower augmentation index and aortic pulse pressure, in spite of elevated BP and arterial stiffness. Thus, possible factors associating higher resting HR with less favourable prognosis in the population studies are higher cardiac workload, elevated BP, and increased arterial stiffness.AIx: Augmentation index; BP: Blood pressure; CI: Confidence interval; CRP: C-reactive protein; HDL: High-density lipoprotein; HR: Heart rate; LDL: Low-density lipoprotein; PWV: Pulse wave velocity.The authors have no conflicts of interest to disclose.JK, AT, IP, JM designed and conducted the study. JK, AT, IP, AJT analysed and interpreted the data, and drafted the first version of the manuscript. JK, AT, AJT, AH, ML, IP, EI, ON and JV performed experiments. JM, AJT, EI, ON, TL, TK and MK gave critical intellectual input and contributed to drafting revised versions of the manuscript. All authors read and approved the final manuscript.The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1471-2261/13/102/prepubRegular medications used by the study population.Click here for file


Arterial stiffness is an important factor in hypertension. Fibulin 2 is an extracellular matrix scaffold protein involved in arterial stiffness and, hence, the fibulin 2 (FBLN2) gene may be a candidate for hypertension susceptibility. 4 single nucleotide polymorphisms (SNPs) of FBLN2 were evaluated in an association case-control study containing 447 hypertensive patients and 344 normotensive control subjects. The minor allele frequencies of rs3732666 and rs1061376 were significantly lower in hypertensives. The odds ratios (OR) for having the protective G (rs3732666) and T (rs1061376) alleles were 0.75 (95%CI: 0.58 to 0.96) and 0.83 (95%CI: 0.66 to 1.02), respectively. For rs3732666, the OR for hypertension in AG+GG subjects, compared with AA, was 0.71 (95%CI: 0.52 to 0.95). The protective genotype AG+GG was associated with significantly lower systolic blood pressure (SBP) [−3.6 mmHg (P = 0.048)]. There was a significant age interaction with rs3732666; the effect decreasing with increasing age. For rs1061376, TT subjects had an OR for hypertension of 0.53 (95%CI: 0.32 to 0.87) compared with CC subjects, with reduced SBP  and diastolic BP (DBP) . The presence of a G allele was an independent predictor of intima-media thickness (IMT); G carrier’s having lower mean IMT  compared with AA. Our results provide the first evidence for FBLN2 as a new gene associated with hypertension. Increases in systolic and diastolic blood pressure  contribute to millions of deaths worldwide every year due to coronary heart disease, stroke, and other vascular diseases Arterial stiffness is defined as a reduction in arterial distensibility Fibulin 2 is an ECM protein first identified in 1990 It is its high binding affinity to elastin that allows fibulin 2 to participate in the mechanisms of elastic fiber assembly Structural alterations of the vessel wall which include fracturing of elastin Based on the postulated role of fibulin 2 in the remodeling and elasticity of the vascular wall, we tested the hypothesis that fibulin 2 may be involved in regulation of blood pressure and, therefore, may be a susceptibility gene for essential hypertension and, indeed, we have shown that variations in FBLN2 gene (rs3732666 and rs1061376) are associated with reduced levels of SBP and decreased risk of hypertension.The study was performed in unrelated and non-selected consecutive white (Caucasian) individuals of the general population who voluntarily attended the University Clinic of Navarra for a routine medical check-up. In this general population, the individuals lack evidence of overt cardiovascular disease . The study population consisted of 344 normotensive subjects and 447 hypertensive patients. By definition, participants were considered hypertensive if they had resting SBP and/or DBP>139 and 89 mmHg, respectively, or if they were prescribed antihypertensive medication. The percentage of hypertensive patients receiving antihypertensive medication reflects what would be observed in a general population in Spain. Resting blood pressure was measured three times using a mercury sphygmomanometer and the mean of these three readings was used in subsequent statistical analyses. All patients had appropriate clinical and laboratory evaluations to exclude secondary hypertension. In accord with our Institution’s guidelines and the Helsinki Declaration, subjects were informed of the research nature of the study and gave written consent prior to participation. The study was approved by the Ethics Committee of the University Clinic of Navarra.http://hapmap.ncbi.nlm.nih.gov/) was used to select the 4 tag SNPs. SNPs were selected for having high minor allele frequency (MAF), for being in different linkage disequilibrium structure and, if possible, for having functional variant status. We selected one non-synonymous SNP located in exon 2 , one intronic SNP (rs1878173) and two synonymous SNPs located in exon 13 and exon 18 (rs4684968 and rs1061376), respectively. These SNPs account for a total of 35% common variation in the FBLN2 gene.We selected fibulin 2 (FBLN2) as a candidate gene involved in blood pressure. We genotyped 4 tag single nucleotide polymorphisms (SNP) in a case-control study sample powered to detect association to rare alleles with an effect size (odds ratio) of 0.7 for hypertension and of 2% of the phenotypic variance for SBP and DBP. The international HapMap database  according to the manufacturer’s instructions.All four SNPs were genotyped using Sequenom’s MassARRAY platform using the iPLEX Gold protocol as specified by the manufacturer  Ultrasound measurements of the common carotid arteries (CCA) were performed as previously reported http://ihg.gsf.de/cgi-bin/hw/hwa1.pl). Continuous variables are expressed as mean ± standard error of the mean (SEM). Differences in clinical and metabolic variables between controls and hypertensive patients were tested by one-way analysis of variance (ANOVA). The χ2 test was used to assess statistical significance of differences in categorical variables. Logistic regression was used to assess the association of genotype with hypertension, while linear regression was used for analysis of continuous variables (SBP and DBP). Logistic and linear analyses were conducted initially using a crude model without adjustment for covariates and without considering any interaction and, subsequently, using a multivariable model adjusted for age, gender, BMI, and smoking. We adjusted for antihypertensive therapy by adding 15 mmHg to SBP and 10 mmHg to DBP. In the multivariable model, all first-order interactions between the SNPs and age, gender, BMI, and smoking were taken into account. First-order interactions were evaluated by the Fisher test. Since the model of inheritance of the SNPs studied is not known, we tested the association analysis without specifying the genetic model, and with no assumptions of specific relationships among genotypes. However, due to the low number of GG subjects in rs3732666, the GG and GA genotypes were pooled and a dominant genetic model was applied. We used stepwise multiple regression analyses to test for associations between the IMT and the selected SNPs and other measured variables. Probability values <0.05 were considered significant.Statistical analyses were performed using SPSS software version 15 for Windows . Power analysis were performed using Genetic Power Calculator Clinical and biometric characteristics of the study subjects are shown in All four SNPs were in HWE in the overall population as well as in the hypertensive and control groups. Two of the tag SNPs (rs3732666 and rs1061376) showed evidence of an association with essential hypertension. For rs3732666, the MAF was significantly lower in hypertensive patients than in control subjects  with an odds ratio (OR) for having the protective allele (G) of 0.75 . MAF of rs1061376 showed a trend towards a lower frequency in hypertensive patients . The differences reached statistical significance  among men, with an OR for having the protective allele (T) in control males of 0.76 . No statistically differences in allele frequencies were observed for rs1878173 and for rs4684968.Comparisons of genotype frequency distributions  showed aThe other two SNPs tested (rs1878173 and rs4684968) showed no evidence of association with hypertension/blood pressure  and, henFor SBP, the β coefficients in the linear regression crude model showed that carriers of allele G (AG+GG), compared to AA homozygotes, had a significantly lower SBP of −4.95 mmHg  . When adFor DBP, although the crude model showed a significant β coefficient for G carriers, this effect was lost when adjusted for gender, age, BMI, and smoking .For the dichotomous trait of hypertension, the logistic regression using the crude model showed that, compared to AA homozygotes, carriers of the G allele had a significantly decreased odds for hypertension  , model 1Crude linear regression models for SBP and DBP were applied , model 1For the dichotomous trait of hypertension, the logistic regression crude model , model 1For rs3732666, stepwise multiple regression analysis showed that the presence of a G allele was an independent predictor of the mean IMT of the right CCA. Additionally, following adjustment for various confounding factors , AG heterozygotes had a significant 0.032 mm decrease in IMT compared with AA homozygotes (p = 0.044). We did not observe any statistically significant effect for GG genotype. Further, as depicted in In this candidate gene study, we have shown that variations in FBLN2 gene (rs3732666 and rs1061376) are associated with lower levels of SBP and decreased risk of hypertension. These two traits are well-established risks factors for atherosclerosis and cardiovascular diseases The data for rs3732666 is consistent with a dominant effect whereas for rs1061376 the data showed a recessive effect since two copies of the minor allele were needed to have an effect on blood pressure. The results for rs3732666 showed an interaction with age for SBP and HTA traits. Conversely, rs1061376 did not show any first-order interactions.The potentially protective role of the FBLN2 SNPs is free of confounding factors since the association was maintained following adjustment for confounding variables such as age, gender, BMI and smoking; factors that have a major contribution to blood pressure variability. We adjusted for antihypertensive therapy by adding 15 mmHg to SBP and 10 mmHg to DBP. This approach has been widely used and has been shown to be a better option than ignoring the treatment or excluding subjects who are on therapy Candidate gene association studies have the advantage that genes can be selected based on known or suspected disease pathways, enabling the investigation of potential causal pathways between the genetic markers selected and complex diseases. Finding an association provides information about its functionality within that pathway. Conversely, many variants identified by GWAS are, often, distant from a protein-coding gene and thus may not have known functional consequences. However, the advantage is that the analysis is not hypothesis driven and, as such, any associations observed would point towards novel areas warranting further investigation.Whether the effect on SBP associated with rs3732666 and rs1061376 is sufficient to decrease cardiovascular disease risk is beyond the remit of our study. However, we could postulate such an effect if we take into account the study by Lewington et al. in which a decrease in 2 mmHg was shown to be associated with a 7% and a 10% reduction in CAD and stroke mortality, respectively The underlying mechanisms by which variations in FBLN2 gene might affect blood pressure are not known. The rs3732666 SNP encoded in exon 2 involves a missense change of an adenine (A) for a guanine (G) which results in a serine to glycine change in aminoacid 361 in the cysteine-free domain of the expressed protein. Changes from serine to glycine residues in other proteins have been shown to result in changes in the affinity, structure, and function of the mature protein Overall, genetic variation can contribute to altered blood pressure regulation by altering the structure of fibulin 2 or by altering FBLN2 gene expression. Fibulin 2 is an important component of the vascular extracellular matrix and, hence, can influence the organization and structure of the vascular wallOur results may provide the first evidence for FBLN2 as a new gene associated with hypertension. We hypothesize that changes either in the structure of fibulin 2, or in its quantitative levels, could be a new mechanism leading to hypertension. Further studies are needed to clarify this point. In addition, even in the absence of a precise underlying molecular mechanism, our results are especially interesting in SBP regulation since there are few protein targets identified for therapeutic intervention, to-date.Our results may provide the first evidence for FBLN2 as a new gene associated with hypertension. We believe that changes either in the structure of fibulin 2, or in its quantitative levels, could be a new mechanism leading to hypertension. Further studies are needed to clarify this point. In addition, even in the absence of a precise underlying molecular mechanism, the identification of this new association may shed further light on new disease mechanisms, especially with respect to SBP regulation since, to-date, there have been few target proteins identified for therapeutic intervention.


Intraoperative arterial hypotension can lead to severe complications in patients undergoing carotid endarterectomy, in particular if cerebral auto-regulation is impaired. Short-acting agents, such as phenylephrine or ephedrine, commonly used to correct intra-operative hypotension, have different hemodynamic effects. Recently, it was reported that, in healthy anesthetized subjects with intact cerebral auto-regulation, frontal lobe cerebral tissue oxygenation declined after phenylephrine bolus administration, while it was preserved after ephedrine use . However, the effect of both agents in patients undergoing carotid endarterectomy is unknown. The aim of this study is to assess the effect of two routinely used vasopressors (phenylephrine and ephedrine) on the cerebral hemodynamics during carotid endarterectomy.Patients undergoing carotid endarterectomy will be prospectively included and randomized for correction of intraoperative hypotension with either phenylephrine (50 to 100 μg) or ephedrine (5 to 10 mg). If hypotension persists for more than five minutes after treatment, the patient will be classified as a non-responder and escape medication as preferred by the anesthesiologist will be administered. Changes in cerebral hemodynamics will be quantified by changes in transcranial Doppler-derived middle cerebral artery blood velocity and near infra-red spectroscopy-derived frontal lobe cerebral tissue oxygenation, when intra-operative hypotension is treated with phenylephrine or ephedrine in patients who undergo carotid endarterectomy with or without an adequate functioning cerebral auto-regulation.To quantify whether the intra-operative cerebral auto-regulation is impaired or not, a decrease in breathing frequency from the normal 12 breaths per minute to 6 breaths per minute for an episode of three minutes will be performed.Phenylephrine and ephedrine are two of the most commonly used short-acting agents to increase blood pressure in clinical anesthesiologic practice. Monitoring of middle cerebral artery blood velocity with transcranial Doppler and frontal lobe cerebral tissue oxygenation with near infra-red spectroscopy are part of the standard of care. Furthermore, there are no reports that the three-minute modification in breathing frequency described in the “intervention”-section is harmful. Therefore, the risks for participating patients are negligible and the burden minimal.Clinical trials.gov: NCT01451294 Carotid endarterectomy (CEA) is the recommended treatment to prevent future cardiovascular events in patients with a symptomatic high degree stenosis of the internal carotid artery (ICA). Besides these symptoms, stenosis of the ICA jeopardizes the cerebral perfusion and may affect cerebral auto-regulation (CA), indicating that cerebral perfusion becomes dependent on changes in blood pressure . TherefoTo do so, different short-acting vasopressor agents can be used, such as phenylephrine or ephedrine . If exis2) decreases during phenylephrine administration while it is preserved with ephedrine use [2[2 and vasomotor tone react after administration of phenylephrine or ephedrine. Thus, the optimal drug to maintain cerebral perfusion in CEA patients, with an impaired CA is unknown. If during the use of one of the two agents cerebral perfusion would be better maintained or even increased this would clearly influence the choice for the desired agent.Besides the difference in systemic hemodynamics, the perfusion of the brain reacts differently. In healthy subjects, with intact CA, the frontal lobe cerebral tissue oxygenation  and middle cerebral artery blood velocity (VMCA) measured by transcranial Doppler (TCD) during CEA. To study the effect of both vasopressors on these parameters, we retrospectively analyzed the effect of phenylephrine and ephedrine induced changes in mean arterial pressure (MAP) on rSO2 and VMCA in 11 CEA patients. We noticed that phenylephrine and ephedrine both increased MAP and VMCA in patients undergoing carotid endarterectomy. However, an increase in MAP induced by phenylephrine has a lowering effect on the rSO2, while ephedrine had an increasing effect on the rSO2[In our institution, we routinely monitor rSO the rSO2.This pilot study indicated that the use of ephedrine should be preferred above the use of phenylephrine for correction of hypotension during CEA. However, the numbers of patients were small and the dose of agent applied not standardized. Therefore, a prospective study to analyze the effect of both ephedrine and phenylephrine on cerebral perfusion during CEA is needed to make a recommendation.2 and TCD derived VMCA, in patients undergoing carotid endarterectomy.Our primary objective is to study the influence of two routinely used drugs to increase MAP (phenylephrine and ephedrine) on cerebral oxygenation and perfusion, estimated by changes in NIRS derived rSOOur secondary objective is to evaluate whether the influence of phenylephrine and ephedrine on cerebral perfusion and oxygenation is different between patients with and without an adequate functioning CA.This study is designed as a prospective randomized trial in a tertiary referral vascular center.The study population will include all patients indicated for CEA because of a symptomatic high degree stenosis of the ICA (discussed in a multidisciplinary meeting) in the University Medical Centre Utrecht (UMCU) who needs use of vasopressor to increase MAP during CEA Figure .To be included in the current study all patients must meet the following criteria:1. Undergoing CEA because of a symptomatic high degree stenosis of the ICA in the University Medical Centre Utrecht.2. Having an appropriate temporal bone window for reliable peri-operative TCD monitoring.3. Having given written informed consent.4. Having a decrease in MAP >20% during surgery.Patients will be excluded if they meet one of the following criteria:1. Not having a temporal bone window appropriate for TCD measurement.2. Not willing to give informed consent.3. No decrease in MAP >20%.4. A heart rate less than 50 beats per minute at the time of administration.5. Hypersensitivity to either ephedrine of phenylephrine.This study is designed as a prospective randomized trial in a tertiary referral vascular center. Currently, the preference of administering either phenylephrine or ephedrine for correction of intraoperative hypotension is mainly based on the physician’s preferences. For this trial randomization based on a computer-generated randomization list will be performed during CEA to counteract changes in MAP more than 20% under baseline with either1) Phenylephrine (50 to 100 μg), or2) Ephedrine (5 to 10 mg),If hypotension persists five minutes after administration of the randomized medication, this patient will be classified as a non-responder and escape medication as preferred by the anesthesiologist will be administered.Before surgery all patients will be informed about the trial procedure. Written informed consent will be obtained from all patients.As part of the standard of care cerebral monitoring, including transcranial Doppler (TCD), Near Infrared Spectroscopy (NIRS) and electroencephalography (EEG) will be provided. To quantify whether the intra-operative cerebral auto-regulation is impaired or not, the breathing frequency will be decreased from the normal 12 breaths per minute to 6 breaths per minute for an episode of three minutes.2 measured using NIRS and VMCA measured using TCD. Our secondary parameter is quantification of cerebral auto-regulation.Our primary study parameters are the changes in rSO2 of −1.5% (± 2) per 10 mmHg increase was seen, while after ephedrine use the rSO2 increased 1% (± 2) per 10 mmHg increase. We calculated that 14 patients in each group would be required to reject the null hypothesis that the population means of the experimental and control groups are equal with probability (power) 0.9. The Type I error probability associated with this test of this null hypothesis is 0.05. Adjusting the sample size to drop out of patients , 20 patients per group will be sufficient.To determine the sample size, we conducted a power analysis based on a retrospective pilot study. In this pilot study (performed in the UMCU), the response within each subject group was normally distributed. After phenylephrine administration a decrease in rSOIn our vascular center, CEA is performed weekly. We assume two patients can be included weekly. Therefore, the estimated length of the study will be approximately six months.Ephedrine is a sympathomimetic amine acting directly on the alpha and β-receptors and indirectly by increasing the release of norepinephrine by the sympathetic nerve endings. As with any sympathomimetic agent, ephedrine stimulates the central nervous system, the cardiovascular system, the respiratory system and the sphincters of the digestive and urinary tract. After intravenous administration, ephedrine is completely biologically available. Intravenous injections are effective within a minute and for up to about 20 minutes. Small quantities of ephedrine are metabolized in the liver, but the majority of ephedrine is excreted unchanged in the urine. Elimination of ephedrine is increased  with decreasing pH of the urine.Phenylephrine hydrochloride is a sympathomimetic agent with mainly direct effects on adrenergic receptors. It has predominantly α-adrenergic activity and is without significant stimulating effects on the central nervous system at usual doses. After injection it produces peripheral vasoconstriction and increased arterial pressure. It also causes a baro-reflex mediated bradycardia. Intravenous injections are effective within a minute and for up to about 20 minutes. Phenylephrine is metabolized in the liver by monoamine oxidase. The metabolites, their route and rate of excretion have not been identified.For both ephedrine and phenylephrine the preparation and labeling will be conducted as in the pharmacy department of the UMC Utrecht. The investigational products are part of the standard of care and, therefore, received, stored and disposed at the pharmacy of the University Medical Center Utrecht.Following connection of the patient to the anesthesia monitor, an intra-arterial catheter in the radial artery is placed in each patient for arterial blood pressure measurement. Induction of anesthesia is achieved with sufentanil (0.3 to 0.7 mcg/kg) and propofol (0.5 to 2.0 mg/kg). Rocuronium (0.3 to 0.5 mg/kg) is used to facilitate tracheal intubation. Anesthesia is maintained using the volatile anesthetic sevoflurane, aiming at a Minimum Alveolar Concentration (MAC) value of 0.5 to 1. Anesthesia-related hypotension is treated with either phenylephrine or ephedrine administration (study medication). In case hypotension persists five minutes after administration of either ephedrine or phenylephrine, the patient will be classified as a non-responder and escape medication as preferred by the anesthesiologist will be administered. Outside the study period, the choice of treatment to correct hypotension will be based on the physician’s preferences. After heparinization, MAP is maintained between −10% and +10% from baseline, until carotid artery cross clamping is performed. At the end of the procedure, the sevoflurane supply will be stopped, and after return of spontaneous respiration, the trachea will be extubated and the patient will be transferred to the recovery ward.VMCA and rSO2 signals.To quantify whether the intra-operative CA is impaired or not, the breathing frequency is decreased from the normal 12 breaths per minute to 6 breaths per minute for an episode of three minutes. To maintain an unchanged minute alveolar ventilation of approximately six liters per minute, the tidal volume has to be almost doubled. The intra-thoracic pressure oscillations created with this way of ventilating will be transferred to the arterial blood pressure signal since a higher intra-thoracic pressure during mechanical insufflation of the lungs will prohibit blood from entering the thoracic cavity. Approximately two heartbeats after the start of the inspiration the amount of blood delivered to the right side of the heart decreases and also the amount of blood leaving the left side of the heart  declines. In the expiration phase the opposite occurs and cardiac output increases. This variation in cardiac output results in a concomitant oscillation in the beat-to-beat registered blood pressure and this is again transferred to the beat-to-beat VMCA would remain totally unaltered despite the 6 per minute blood pressure oscillations as elicited with the ventilator in anesthetized subjects. In reality, CA behaves like a high pass filter. This means that oscillations with a duration of 10 seconds in blood pressure will be present but dampened in the VMCA signal. Furthermore, oscillations in VMCA in this frequency area precede those in MAP by approximately two to three seconds. The better CA functions the more the amplitude of the oscillation in VMCA will be dampened and the more the VMCA signal precedes the blood pressure signal.Intact CA implies that the cerebral perfusion remains constant despite changes in blood pressure. Hypothetically, this means that the A radial artery catheter is placed in each patient for continuous blood pressure measurement.Cardiac output monitoring:Noninvasive arterial pressure (NAP) will be measured using the Nexfin monitor , which uses an improved finger cuff technology with high sensitivity optical components and fully digital control systems. In addition, brachial arterial blood pressure is reconstructed from the measured finger arterial pressure using waveform filtering to approximate a brachial pressure wave, together with pressure level correction compensating for the finger to radial pressure difference. An appropriate size finger cuff will be applied to the mid-phalanx of the middle finger ipsilaterally to the invasive blood pressure catheter. The “heart reference system”, which measures and corrects the hydrostatic difference between the finger and the heart, will be set at the arterial pressure transducer level.2 measurements will be performed using Invos Cerebral Oximeter , which allows continuous monitoring of cerebral oxygenation, by penetrating the scalp and brain tissue whereby the skin, scull and other tissues are relatively transparent to near-infrared wavelengths of light. Changes in concentrations of oxygenated and deoxygenated hemoglobin are measured by a modified Beer-Lambert method and because of the different wavelengths of the oxygenated and deoxygenated hemoglobin, these can be distinguished and the ratio of oxygenated hemoglobin to total tissue hemoglobin (TOI) can be defined. By using two detectors the light reflected and transmitted by the superficial extracranial tissues is subtracted.Bilateral rSOFor all TCD registrations a pulsed Doppler transducer  gated at a focal depth of 45 to 60 mm, will be placed over the temporal bone to insonate the main stem of the ipsilateral middle cerebral artery and the contralateral anterior cerebral artery.VMCA, will be measured continuously.After tracheal intubation, TCD is applied. The TCD probes are fitted in a light metal frame, which is firmly fixed to the head with two earpieces and an adjustable nose saddle. The For measuring the cerebral function state and detecting signs of cerebral ischemia, used as an indication for selective shunting during CEA, electroencephalography  is used. Prior to starting anesthesia, EEG electrodes will be applied to the patient’s skull and the EEG will be continuously registered during surgery.A vascular surgeon or vascular trainee under supervision will perform carotid surgery in a standardized way. Patients will receive 5,000 IU heparin three minutes before cross-clamping the carotid artery. The decision for a venous, prosthetic or bovine patch will be made by preference of the surgeon. An intra-luminal shunt will selectively be used based on TCD and/ or EEG criteria as described in the literature .The principal investigator, who will inform individual participants about the study, will do patient recruitment. Informed consent will be obtained as soon as possible, but must be acquired before surgery. The patient information letter and informed consent form are attached as a separate document.Subjects can leave the study at any time for any reason if they wish to do so without any consequences. The investigator can decide to withdraw a subject from the study for urgent medical reasons. Any patient with incomplete data registration can be withdrawn and replaced by a consecutive patient.Patients will receive no follow-up other than regular follow-up procedures following carotid endarterectomy (outpatient clinic visit combined with duplex ultrasound of the operated carotid bifurcation).Adverse events, serious adverse events and suspected, unexpected, serious adverse reactions will be recorded and reported according to the requirements of the accredited medical ethical committee.The MAP, TCD and NIRS measurements will be presented as continuous variables for both of the randomized groups.2 and VMCA an intention-to-treat analysis will be used. For this analysis all patients that received either ephedrine or phenylephrine will be included (both responders and non-responders). Subsequently, a sub analysis will be performed to compare the changes in rSO2 and VMCA per 1 mmHg increase between patients that received either ephedrine or phenylephrine. For this sub analysis only the responders will be included.To examine the effect of either ephedrine or phenylephrine on rSO2 and VMCA, the Student’s t-test will be used. The relationship will be calculated at two different time points:To compare the relationship between the phenylephrine and ephedrine group in an rSO2) and• two minutes after either phenylephrine or ephedrine administration (tmax).• at the moment the maximum increase in blood pressure is reached . A confidence level of less than 5% (0.05) is considered significant.-1 with a normal ventilatory frequency of 12 min-1 are approximately 15 and 5 mmHg, respectively. During a ventilatory frequency of 6 min-1 inspiratory and expiratory airway pressures will rise to approximately 25 and 5 mmHg. This is comparable to airway pressures observed during laparoscopic surgery when the abdomen is inflated with carbon dioxide or during surgery with the body in 20° Trendelenburg position.Since both phenylephrine and ephedrine have been routinely used for years and all measurements are part of the standard of care, no side effects are expected. Furthermore, there are no reports that the three-minute modification in breathing frequency described in the “intervention”-section is harmful. Varying breathing frequencies while maintaining minute ventilation results in larger tidal volumes and, therefore, an unchanged oxygen uptake and carbon dioxide remove, which can be measured using a pulse oximeter. Larger tidal volumes, however, result in higher airway pressures during low frequency ventilation. Inspiratory and expiratory airway pressures in healthy lungs during 6 mL·kgTherefore, the risks for participating patients are negligible and the burden minimal.To our best knowledge this trial represents the first attempt to evaluate the differential effects of phenylephrine and ephedrine in correction of intraoperative hypotension during CEA. If either of these drugs is shown to be superior with respect to the cerebral hemodynamics, results from our study will provide clinical trial evidence for the management of blood pressure during CEA.The Medical Ethics Committee (METC) of the University Medical Center Utrecht has approved this study protocol. The trial has already been started in October 2012; the estimated length of the study will be six months.2: The frontal lobe cerebral tissue oxygenation; TCD: Transcranial Doppler; TOI: The ratio of oxygenated hemoglobin to total tissue hemoglobin; UMCU: University Medical Centre Utrecht; VMCA: Middle cerebral artery blood velocity.CA: Cerebral auto-regulation; CEA: Carotid endarterectomy; EEG: Electroencephalography; ICA: Internal carotid artery; MAC: Minimum Alveolar Concentration; MAP: Mean arterial pressure; METC: Medical Ethics Committee; NAP: Noninvasive arterial pressure; NIRS: Near infrared spectroscopy; rSOThe authors declare they have no competing interests in relation to this manuscript.CP participated in the design of the study and drafted the manuscript. RV and GB participated in the design of the study and helped to draft the manuscript. WB and FM participated in the design of the study and critically revised the manuscript. All authors read and approved the final manuscript.


Asthma affects an estimated 300 million people worldwide. Poor compliance with prescribed medication leads to increased morbidity and mortality. The number of asthma cases has more than doubled since 1980 and, nearly 3 million workdays are lost annually due to asthma exacerbations. Non-compliance with therapy is a major impediment to effective asthma management and can lead to failure of treatment. The purpose of the study was to identify the better predictor for adherence behaviors between knowledge of asthma, health beliefs, attitude toward the illness of asthma, and behavioral intention to adhere.This cross sectional study was conducted among adult asthmatic patients in three private asthma clinics in Yazd city, Iran. Data was collected using face to face interview. During the interview a validated Questionnaire was used to assess patients’ knowledge about ICS,' positive and negative health beliefs and attitudes a about ICS, behavioral intention to comply with treatment, and compliance rate. A 4-item patient-report scale was used to measure medication adherence.Response rate of participants 94%, adult (≥16 years old) with prescribed ICS reported were included (n=112). Analysis showed that majority of patients (55.5%) was non adherence to their prescribed ICS. Patients’ knowledge toward ICS did not have effect on medication adherence behavior, while patients with positive attitude toward ICS were better adherent with their medication. A simple linear regression identified intention to comply with treatment and positive attitude toward ICS as predictors for adherence behavior.The findings confirm a relationship between medication attitude and adherence among asthmatic patients. A better understanding of patients’ attitude and its impact on adherence may help clinicians counsel effectively to promote adherence.


Background. Asthma in the elderly is an important public health problem. The aim of this study was to assess the prevalence and characteristics of asthma in seniors. Materials and Methods. The study involved 105 people of at least 80 years of age (mean age of 84.1 ± 3.9 years) selected from a group of 1860 individuals. Spirometry, the methacholine test, allergy diagnosis, a measurement of exhaled nitric oxide, and administration of the asthma quality of life questionnaire (AQLQ) were performed. Results. The average morbidity of asthma in the study population of elderly people (at least 80 years of age) was 5.6% (105 people) of the confidence interval (95% CI: 5.1–6.0). In the study group, 34% of the elderly asthmatics had uncontrolled asthma, 47% had partly controlled asthma, and only 24% had fully controlled asthma. Allergy to house dust mites was predominant. The average total score on the AQLQ was 4.12 ± 0.72 (arithmetic mean ± standard deviation) for the seniors, which was significantly lower than the score for the young. Conclusion. The pathogenesis, natural history, and value of the basic diagnostic methods of asthma in the elderly are similar to those observed in younger age groups. Bronchial asthma is an increasing problem in all age groups. However, there is still not enough information about the natural course and clinical features of asthma in seniors. Additionally, a clear diagnosis of asthma in patients over 80 years of age is difficult , 2. SimiThe aim of the study was to assess the differences between the clinical features of asthma in patients over 80 years old and youth. This study could successfully draw the necessary attention to the special needs of these patients.The study group enrolled 105 patients who were at least 80 years old and had a preliminary diagnosis of asthma. The recruitment of respondents was conducted in eight centers representative of the Polish population. Stratification sampling was performed from 1860 patients in the key age group of over 80 years of age. The control group consisted of young patients diagnosed with asthma and selected from GP clinics in the same areas of residence as the group of elderly patients. Stratification sampling was also performed, with a key age group of 18–30 years of age. Asthma was diagnosed on the basis of the ECRHS II questionnaire . Before Dermatophagoides pteronyssinus, Dermatophagoides farinae, Aspergillus fumigatus, Alternaria tennis, Cladosporium herbarum, dog dander, cat dander, grass mix, birch, alder, hazel, and mugwort. IgE values above 0.35 kU/l were considered to be a positive result [Measurement of the concentration of total IgE and allergen-specific IgE (sIgE) was performed using the Pharmacia CAP System FEIA , and the values are shown in kU/l . Researce result .In the study, SPTs were obtained from Allergopharma , corresponding to a set of allergen-specific IgEs. The tests were performed according to the guidelines .The level of fractional exhaled nitric oxide (FENO) was assessed in the senior group of patients and the young asthmatic control group. The determination of FENO was performed using a manual analyzer, the MINO Airway Inflammation Niox Monitor , measuring the exhaled fraction of nitric oxide by an electrochemical method . The patA patient quality-of-life assessment was performed using the asthma quality of life questionnaire (AQLQ) developed by Juniper, whose application was approved. The questionnaire included questions about the group: the environmental exposure of the patients, the reduction in physical activity by the disease, the patient's emotional evaluation in the context of the disease, and the symptoms of the disease itself. For each of the 32 questions, the patient responded on a scale of 1–9 points, with the lowest to the highest value representing the worst to the best assessment. Details of the questionnaire can be found in the literature .t-test for independent samples. To assess the correlation of the results of the skin tests and IgE measurements, Spearman's test was used. In addition, the logarithms of the IgE values met the criterion for a normal distribution, so Pearson's correlation test was used. Odds ratios were calculated to assess the likelihood of asthma in the presence of a particular trait in the subjects. Multiple linear regression analysis was used for the dependent variable, which was the duration of asthma, and for independent variables, such as smoking, the IgE value, asthma control, the ACT score, the severity of asthma, and the presence of allergic rhinitis. The statistical analyses used a Bonferroni correction. A P value of <0.05 was considered significant.For comparison, data meeting the criterion of a normal distribution, such as the age of the participants, the duration of the disease, and the results of the spirometry tests, were analyzed using a Student's The study was approved by the Bioethical Committee of the University Medical School of Silesia in Katowice, Poland.Based on data from 1860 screened individuals, the prevalence of asthma associated with age and sex in the study population of elderly people (at least 80 years of age) was 5.6% (105 people) of the confidence interval (95% CI: 5.1–6.0). There were 63 women and 42 men with a mean age of 84.1 ± 3.9 years (range of 80 to 97 years). The control group included 102 young patients with a mean age of 22.1 ± 5.2 years (range of 18 to 32 years), including 45 women and 67 men.The demographic data for the patients and the degree of the control of asthma are shown in P < 0.05). However, there was no statistical difference between percentage of normal range according to age which was obtained by elderly and young. An allergy to the house dust mite D. pteronyssinus and/or D. farinae (positive skin tests and corresponding IgE) was predominant in approximately 47% and 45% of the young and old patients, respectively. This followed by a grass pollens (27% in elderly versus 24% in young), tree pollens (29% versus 28%), cockroach (21% versus 19%), molds (15% versus 9%), and animal dander (10% versus 9%). The results of the tests, including for specific IgE, were comparable between the two groups, except for a significant predominance of allergy to molds in the elderly (P < 0.05). The mean spirometric values were as follows: mean FEV1 in elderly asthmatics: 1.21 ± 0.45 L ; mean FVC in elderly asthmatics: 1.73 ± 0.43 L ; mean FEV1 in young asthmatics: 1.87 ± 0.49 L ; and mean FVC in young asthmatics: 2.31 ± 0.69 L . There was a significant difference between the elderly and youth in absolute value  patients (increase in the FEV1 of ≥12% or an increase of 200 mL). In total, 11 (10.5%) patients had negative result of reversibility test. In 8 (7%) patients, the test could not be performed because of a lack of cooperation. Patients in the last two subgroups (11 plus 8 people) underwent assessment with a test for methacholine bronchial hyperreactivity, which indicated that 14 (13.3%) patients met the criterion for the diagnosis of asthma (FEV1 decline of 20%). Due to a low FEV1 value , 17 patients withdrew from the study. Finally, 5 (4.8%) patients were classified into groups with COPD or asthma/COPD overlap syndrome . They were excluded from the study. The evaluation of the measurement of nitric oxide is shown in t-test, P < 0.05). A similar trend was observed for each of the analyzed domains: environmental exposure: 4.13 ± 0.53 in seniors versus 5.16 ± 0.33 in young (P < 0.05); emotional function: 4.32 ± 0.61 versus 4.90 ± 0.34 (P < 0.05); and activity: 4.01 ± 0.55 versus 5.4 ± 0.63 (P < 0.05). The quality of life was significantly correlated with better asthma control according to the ACT . AQLQ scores did not correlate with spirometric values (FEV1).The average total score on the AQLQ was 4.12 ± 0.72 (arithmetic mean ± standard deviation) for seniors, which was significantly lower than the score for the youth: 5.12  ±  0.48 (Student's The obtained results showed lack of significant differences between clinical features of asthma in seniors and young. The severity of the disease, the result of ACT, and the degree of asthma control were similar to young patients. This phenomenon is interesting and contradicts the observations between asthmatic patients aged 50–70 years compared with the young as it was confirmed in previous studies , 17 wherThe performed pulmonary function studies highlighted the value of spirometry in the diagnosis and monitoring of asthma in older patients. There was no significant difference in reversibility tests and obtained percentage of normal ranges of of FEV1 and FVC. However, there are differences between absolute values of FEv1 and FVC as it was in previous observations , 18. TheThe worse quality of life in seniors with confirmed asthma than in the young may be an evidence for the poorer diagnosis and treatment of and interest in this group of patients. It is emphasizes earlier , 19.Asthma in the elderly is an important public health problem. This condition's pathogenesis and natural history and the value of basic diagnostic methods are similar to those observed in younger age groups. There is a need to pay more attention to the disease in patients over 80 years old, which would prevent the underdiagnosis and undertreatment of asthma.