Miguel Gus

Prevalence, awareness, and control of systemic arterial hypertension in the state of Rio Grande do Sul.

OBJECTIVE To report the prevalence of cardiovascular risk factors, particularly of systemic arterial hypertension, in the adult population of the Brazilian state of Rio Grande do Sul, in addition to the publics level of awareness, hypertensive control, and associated factors. METHODS A cross-sectional, population-based study with random sampling from a population pool was carried out with 918 patients older than 20 years from 1999 to 2000. Systemic arterial hypertension was defined as blood pressure > or = 140/90 or current use of antihypertensive drugs. RESULTS The prevalence of systemic arterial hypertension was 33.7% (n = 309), and 49.2% of the individuals were unaware of their hypertensive condition; 10.4% knew they were hypertensive, but did not undergo treatment; 30.1% underwent antihypertensive treatment, but did not have adequate control; and 10.4% underwent antihypertensive treatment with adequate control. Based on multivariate analysis, the following variables were found to be significantly associated with the presence of systemic arterial hypertension: age (OR = 1.06), obesity (OR = 3.03), and low educational level (OR = 1.82). These same variables were associated with unawareness of the hypertensive condition: age (OR = 1.05), obesity (OR = 2.46), and low educational level (OR = 2.17). CONCLUSION Prevalence of systemic arterial hypertension in the state of Rio Grande do Sul has been remained at constant levels for the past decades, and the populations level of awareness of it has improved slightly. However, the control level of systemic arterial hypertension has not increased. This study allowed the definition of a target group -- elderly, obese individuals with low educational level -- for both diagnostic campaigns and better control of blood pressure levels.

Diagnosis of Obstructive Sleep Apnea Syndrome and Its Outcomes With Home Portable Monitoring

BACKGROUND The use of portable respiratory monitoring (PM) has been proposed for the diagnosis of obstructive sleep apnea syndrome (OSAS), but most studies that validate PM accuracy have not followed the best standards for diagnostic test validation. The objective of the present study was to evaluate the accuracy of PM performed at home to diagnose OSAS and its outcomes after first validating PM in the laboratory setting by comparing it to polysomnography (PSG). METHODS Patients with suspected OSAS were submitted, in random order, to PM at the sleep laboratory concurrently with PSG (lab-PM) or at home-PM. The diagnostic performance was assessed by sensitivity, specificity, positive and negative predictive values, positive likelihood ratio (+LR), negative likelihood ratio (-LR), intraclass correlation coefficients, kappa statistic, and Bland-Altman plot. RESULTS One hundred fifty-seven subjects (73% men, mean age +/- SD, 45 +/- 12 yr) with an apnea-hypopnea index (AHI) of 31 (SD +/- 29) events/h were studied. Excluding inadequate recordings, 149 valid comparisons with lab-PM and 121 with unattended home-PM were obtained. Compared to PSG for detecting AHI > 5, the lab-PM demonstrated sensitivity of 95.3%, specificity of 75%, +LR of 3.8, and -LR of 0.11; the home-PM exhibited sensitivity of 96%, specificity of 64%, +LR of 2.7, and -LR of 0.05. Kappa statistics indicated substantial correlation between PSG and PM results. Bland-Altman plot showed smaller dispersion for lab-PM than for home-PM. Pearson product moment correlation coefficients among the three AHIs and clinical outcomes were similar, denoting comparable diagnostic ability. CONCLUSIONS This study used all available comparison methods to demonstrate accuracy of PM in-home recordings similar to that of repeated PSGs. PM increases the possibility of correctly diagnosing and effectively treating OSAS in populations worldwide.

Risk for Obstructive Sleep Apnea by Berlin Questionnaire, But Not Daytime Sleepiness, Is Associated With Resistant Hypertension: A Case-control Study

BACKGROUND Obstructive Sleep Apnea Syndrome (OSAS) is a risk factor for resistant hypertension. Overnight polysomnography and portable sleep monitors are not generally available and questionnaires may be useful for screening OSAS. In a case-control study, we investigate the association between resistant hypertension and sleep disorders evaluated by the Berlin Questionnaire and Epworth Sleepiness Scale (ESS). METHODS Cases were 63 patients with resistant hypertension (either systolic blood pressure (BP) > or =140 mm Hg or diastolic BP > or =90 mm Hg using at least three BP-lowering drugs, including a diuretic). Controls were 63 patients with controlled BP under drug treatment. All the patients were submitted to ambulatory BP monitoring and level III polysomnography by means of a portable monitor. The prevalence of high risk in the Berlin Questionnaire and high score in the ESS (>10) was compared between the groups. Diagnostic performance for OSAS of both questionnaires was calculated. RESULTS The prevalence of high score in ESS was 44% in both groups. There was a higher prevalence of high risk for OSAS in Berlin Questionnaire in the cases group (78% vs. 48%; P < 0.001). In a logistic regression model, high risk for OSAS in Berlin Questionnaire was independently associated with resistant hypertension (odds ratio 4.1; confidence interval 95% 1.80-9.31; P < 0.01). Sensitivity and specificity for the diagnosis of OSAS was 85.5% (75.3-92.0%) and 65.0% (52.0-76.0%), respectively. CONCLUSIONS High risk for OSAS assessed by the Berlin Questionnaire is highly prevalent and associated with resistant hypertension. This questionnaire may be used as screening for OSAS in patients with this clinical condition.

Associação entre diferentes indicadores de obesidade e prevalência de hipertensão arterial

PURPOSE To evaluate the association between body mass index (BMI), waist-hip ratio and waist circumference with the prevalence of hypertension in a representative sample of 1088 adults of Porto Alegre (RS), Brazil. METHODS In this cross-sectional survey, subjects were considered as having hypertension if they had systolic blood pressure > or = 160 mmHg or diastolic > or = 90 mmHg, and were considered obese if they had BMI > or = 27 kg/m2, or had a waist-hip-ratio > or = 0.95 cm (men) or 0.80 (women) or had a waist circumference > or = 96 (men) or 92 (women). RESULTS Obesity defined by the BMI was associated with hypertension in both genders (RR 1.9, CI 1.0-3.2 in men; RR 2.2, CI 1.3-3.8 in women). The other indices were significantly associated with hypertension just in women. CONCLUSION BMI > or = 27.0 kg/m2 was strongly associated with increased odds to have hypertension. Similar magnitude of the association with the other indices indicate their utility to estimate the risk of hypertension.PURPOSE: To evaluate the association between body mass index (BMI), waist-hip ratio and waist circumference with the prevalence of hypertension in a representative sample of 1088 adults of Porto Alegre (RS), Brazil. METHODS: In this cross-sectional survey, subjects were considered as having hypertension if they had systolic blood pressure ³160mmHg or diastolic³90mmHg, and were considered obese if they had BMI ³27kg/m2, or had a waist-hip-ratio ³0.95cm (men) or 0.80 (women) or had a waist circumference ³96 (men) or 92 (women). RESULTS: Obesity defined by the BMI was associated with hypertension in both genders (RR 1.9, CI 1.0 - 3.2 in men; RR 2.2, CI 1.3 - 3.8 in women). The other indices were significantly associated with hypertension just in women. CONCLUSION: BMI ³ 27.0kg/m2 was strongly associated with increased odds to have hypertension. Similar magnitude of the association with the other indices indicate their utility to estimate the risk of hypertension.

Is Epistaxis Evidence of End-Organ Damage in Patients With Hypertension?†

Objectives/Hypothesis: To study the association between history of mild to severe epistaxis with different stages of hypertension and with other evidence of target organ damage in a sample of patients attending an outpatient hypertension clinic, controlling for potential confounding factors. Study Design: A survey of adult patients with hypertension. Methods: A consecutive sample of 323 adults with hypertension was studied. The main outcome measures were history of adult epistaxis, high blood pressure, duration of hypertension, nasal abnormalities, and fundoscopic and electrocardiogram abnormalities. Results: Ninety‐four patients (29.1% of the whole sample) reported at least one episode of nosebleed after 18 years of age. Of these, 59 (62.8%) needed medical assistance to control at least one of the episodes. The history of epistaxis was not associated with blood pressure classified according to the World Health Organization/International Society of Hypertension paradigm or classified as severe or not severe. There was a trend of an association between history of epistaxis and duration of hypertension. The history of severe epistaxis (epistaxis that needed medical assistance) was not associated with blood pressure classified as severe or not severe and with duration of hypertension. More patients with left ventricular hypertrophy had a positive history of adult epistaxis. There was no association between history of epistaxis or history of severe epistaxis and fundoscopic abnormalities. Among the abnormalities detected at rhinoscopy, only the presence of enlarged septal vessels was associated with history of epistaxis. The presence of enlarged septal vessels was strongly and independently associated with history of epistaxis in the logistic regression model. Duration of hypertension and left ventricular hypertrophy showed a trend for an association with the history of epistaxis in the adult life. Conclusions: A definite association between blood pressure and history of adult epistaxis in hypertensive patients was not found. The evidence for an association of duration of hypertension and left ventricular hypertrophy with epistaxis suggests that epistaxis might be a consequence of long‐lasting hypertension. The association between the presence of enlarged vessels at rhinoscopy with history of epistaxis in hypertensive patients is a novel observation that needs to be addressed in future observations.

Blood pressure effects of antihypertensive drugs and changes in lifestyle in a Brazilian hypertensive cohort

Background The antihypertensive efficacy of drug therapy and of some nonpharmacologic recommendations has been demonstrated in controlled clinical trials, but not in a clinical setting. Objective To assess the antihypertensive effectiveness of drug therapy and of three nonpharmacologic recommendations (loss of weight, salt-intake restriction, and physical exercise). Design A prospectively planned cohort study. Setting A hospital-based hypertensive outpatient clinic. Patients We studied 637 patients (65.5% women) with systolic blood pressures above 140 mmHg or diastolic blood pressures above 90 mmHg, corresponding to 76% of 839 patients who were administered a prescription for hypertension and who returned for the first follow-up visit 3.5 months later on average. Methods The nonpharmacologic prescription consisted of salt-intake restriction for all, weight reduction for overweight patients, and practice of aerobic physical exercise for those for whom it was not contraindicated; 60% of the patients were treated with drugs according to standard recommendations. Patients treated with drugs were compared with untreated subjects; for the nonpharmacologic interventions, the groups were compared according to their reported compliances with the recommendations (at least some compliance versus none). The main outcome measures were variations in systolic and diastolic blood pressures between the baseline evaluation and the first follow-up visit and an improvement in prognosis, represented by a favorable change in the classification of the blood pressure (according to Joint National Committee V criteria). Results The cohort constituted predominantly low-income, middle-aged, overweight white women, with low-to-moderate hypertension of long duration. The group treated with drugs exhibited the greatest reduction in blood pressure, with clinical significance even discounting the losses in follow-up; the group of patients who reported compliance with the low-energy-intake diet also showed a consistent antihypertensive effect, which was still detectable on the occasion of the third follow-up visit 9 months after the first prescription; reported compliance with a low-sodium diet and practice of physical exercise were not associated with a reduction in blood pressure; among a subset of the patients, reported compliance with the salt-intake-restricted diet did not reduce the amount of sodium to the theoretical antihypertensive threshold. It was not possible to determine whether the lack of an antihypertensive effect of physical exercise for this cohort was secondary to a misreport of the extent of compliance or to an absence of effect of the intensity of training prescribed. The effects of drug therapy and compliance with a low-energy-intake diet were shown to be independent of other interventions or confounders. Conclusion The antihypertensive effect of drugs demonstrated in well-controlled clinical trials is achievable in clinical practice. The recommendation to lose weight was the only nonpharmacologic intervention with a detectable antihypertensive effect in this cohort. The absence of effect of a low-sodium diet is probably secondary to the insufficient reduction in the amount of salt consumed. The lack of an antihypertensive effect of physical exercise could reflect either a misreported compliance or an absence of effect of the intensity of training recommended in this study.

Waist circumference cut-off values to predict the incidence of hypertension: an estimation from a Brazilian population-based cohort.

BACKGROUND AND AIMS Central obesity is a key component in the definition of the metabolic syndrome, but the cut-off values proposed to define abnormal values vary among different guidelines and are mostly based on cross-sectional studies. In this study, we identify the best cut-off values for waist circumference (WC) associated with the incidence of hypertension. METHODS AND RESULTS Participants for this prospectively planned cohort study were 589 individuals who were free of hypertension and selected at random from the community of Porto Alegre, Brazil. Hypertension was defined by a blood pressure measurement >or= 140/90 mmHg or the use of blood pressure lowering drugs. A logistic regression model established the association between WC and the incidence of hypertension. A receiver operating characteristics (ROC) curve analysis was used to select the best WC cut-off point to predict the incidence of hypertension. During a mean follow-up of 5.5+/-0.9 years, 127 subjects developed hypertension. The hazard ratios for the development of hypertension, adjusted for age, baseline systolic blood pressure, alcohol consumption, gender and scholarship were 1.02 (95% CI; 1.00-1.04; P=0.02) for WC. The best cut-off WC values to predict hypertension were 87 cm in men and 80 cm in women, with an area under the curve of 0.56 (95% CI; 0.47-0.64; P=0.17) and 0.70 (95% CI; 0.63-0.77; P<0.001), respectively. CONCLUSION Excess visceral adiposity is a major risk factor for hypertension in individuals living in communities in Brazil, and this risk begins at lower values of WC that those recommended by some guidelines.

Incidence of hypertension by alcohol consumption: is it modified by race?

Objective To investigate the influence of race, binge drinking and alcohol addiction on the association between consumption of alcoholic beverages and incidence of hypertension. Methods In a population-based cohort study, 1089 adults were interviewed and had blood pressure and anthropometric measurements carried out at home. Their alcohol consumption was ascertained by an amount–frequency questionnaire. Binge drinking was defined as consumption of five or more drinks on one occasion for men or four drinks for women, and abuse of alcohol as consumption of 30 g/day or more in men or 15 g/day or more in women. Incident cases of hypertension were characterized by blood pressure ≥ 140/90 mmHg or use of hypertension medication. Results Among 589 normotensive individuals in the baseline visit, 127 incident cases of hypertension were identified, after a follow-up of 5.6 ± 1.1 years. Binge drinking and alcohol dependency were not associated with the incidence of hypertension. Adjusted (age, education) risk ratios for the incidence of hypertension (95% confidence interval) were significant only for non-white abusers of ethanol: 11.8 (1.6–86.9). Systolic blood pressure of black abusers increased by 16.1 ± 3.5 mmHg, in comparison with 4.9 ± 1.5 mmHg among white abusers (P = 0.004). Conclusion Individuals with an African ancestry, who consumed larger amounts of ethanol, are at higher risk of developing hypertension. This risk is not explained by a binge drinking pattern or addiction to alcohol.

Influence of sleep apnea severity on blood pressure variability of patients with hypertension

PurposeObstructive sleep apnea (OSA) is a risk factor for the development of hypertension and cardiovascular disease. Apnea overloads the autonomic cardiovascular control system and may influence blood pressure variability, a risk for vascular damage independent of blood pressure levels. This study investigates the hypothesis that blood pressure variability is associated with OSA.MethodsIn a cross-sectional study, 107 patients with hypertension underwent 24-h ambulatory blood pressure monitoring and level III polysomnography to detect sleep apnea. Pressure variability was assessed by the first derivative of blood pressure over time, the time rate index, and by the standard deviation of blood pressure measurements. The association between the apnea–hypopnea index and blood pressure variability was tested by univariate and multivariate methods.ResultsThe 57 patients with apnea were older, had higher blood pressure, and had longer duration of hypertension than the 50 patients without apnea. Patients with apnea–hypopnea index (AHI) ≥ 10 had higher blood pressure variability assessed by the standard deviation than patients with AHI < 10 during sleep (10.4 ± 0.7 versus 8.0 ± 0.7, P = 0.02) after adjustment for age, body mass, and blood pressure. Blood pressure variability assessed by the time rate index presented a trend for association during sleep (P = 0.07). Daytime blood pressure variability was not associated with the severity of sleep apnea.ConclusionSleep apnea increases nighttime blood pressure variability in patients with hypertension and may be another pathway linking sleep abnormalities to cardiovascular disease.

Blood pressure-lowering efficacy of amiloride versus enalapril as add-on drugs in patients with uncontrolled blood pressure receiving hydrochlorothiazide.

A large proportion of patients with hypertension need a second drug to reach satisfactory control of blood pressure (BP), but there are few well-designed controlled trials comparing the efficacy of drugs added as a second option. In a double-blind randomized clinical trial, 82 patients with uncontrolled BP, receiving hydrochlorothiazide 25 mg daily, were selected to receive amiloride 2.5–5 mg/day (n = 39) or enalapril 10–20 mg/day (n = 43). Ambulatory blood pressure monitoring (ABPM) was done before and after 12-weeks of treatment. Office BP was measured in the 4th, 8th, and 12th weeks. The doses of amiloride and enalapril were doubled in the fourth week, and propranolol was added in the 8th week if office BP was above 140/90 mm Hg. There was a greater BP reduction in patients treated with enalapril. The ABPM δ values between the groups were 3.6 ± 2.2, 3.9 ± 2.2, and 1.1 ± 2.7 mmHg for 24-h, daily, and nightly systolic blood pressure, respectively, favoring enalapril. For diastolic blood pressure (DBP), the deltas were 1.7 ± 2.0, 3.2 ± 1.5, and 1.2 ± 1.9 mmHg, respectively (p = 0.039 for daily DBP). Office SBP decreased more and sooner in patients allocated to enalapril (p = 0.003). More patients taking amiloride required propranolol to control BP (p = 0.035). Potassium increased 0.3 mEq/L on the average in both groups. Cough, albeit predominantly mild, was reported more frequently by participants treated with enalapril. We conclude that enalapril is more effective than amiloride to lower BP of patients on hydrochlorothiazide with uncontrolled BP. Trial registration: ClinicalTrials.gov identifier: NCT00394394.