Does psychosocial stress cause hypertension? A systematic review of observational studies.

Acute stress promotes transient elevation of blood pressure, but there is no consistent evidence that this effect results in hypertension. In this systematic review of cohort and case-control studies that investigated the association between psychosocial stress and hypertension, we conducted a complete search up to February 2007 in MEDLINE, EMBASE, PSYCINFO and LILACS, through a search strategy that included eight terms to describe the exposure, six related to the design of the studies and one term for outcome. The quality was assessed by the Newcastle-Ottawa Quality Assessment Scale. The selection was done in duplicate by two teams of independent reviewers. Among 82 studies selected in the second phase, only 14 (10 cohort studies and 4 case-control studies), totalling 52,049 individuals, fulfilled the selection criteria. The average quality of the studies was 6.6+/-1.3 in a 9-point scale. Acute life events were associated with hypertension in one and were not associated in two studies. Five out of seven studies found a significant and positive association between measures of chronic stress and hypertension, with risk ratios ranging from 0.8 to 11.1. Three out of five studies reported high and significant risks of affective response to stress for hypertension, one a significant risk close to a unit and one reported absence of risk. Acute stress is probably not a risk factor for hypertension. Chronic stress and particularly the non-adaptive response to stress are more likely causes of sustained elevation of blood pressure. Studies with better quality are warranted.

Validity and reliability of the dietary sodium restriction questionnaire in patients with hypertension.

The study aimed to evaluate the reliability and the validity of the dietary sodium restriction questionnaire (DSRQ) in patients with hypertension receiving outpatient treatment at a tertiary care university hospital in Southern Brazil. This instrument is composed of three subscales: attitude, subjective norm and perceived behavioral control. A total of 104 patients were included. They were 63.3±8.9 years old and 75% were females. Cronbach's alpha coefficient for the subscales of attitude, subjective norm and perceived behavioral control were 0.75, 0.37 and 0.82, respectively. The PCA with the extraction of three factors explained a total of 53.5% of the variance. The data suggest that the 15-item DSRQ is reliable and has internal consistency of its construct to measure the barriers and the attitudes of hypertensive patients related to dietary sodium restriction and may be useful to improve blood pressure control.

Absence of association between depression and hypertension: results of a prospectively designed population-based study.

The objective of this study was to examine the relation between hypertension and depression. In a cross-sectional study of the urban region of a State capital with more than 1.5 million inhabitants, 1174 men and women aged 18-80 years, selected at random from the population, were studied. Blood pressure, hypertension (blood pressure readings >or=140/90 mm Hg or use of blood pressure-lowering agents), risk factors for hypertension and depression according to the Diagnostic and Statistical Manual of Mental Disorders (fourth edition) were investigated in home interviews. The prevalence of major depression and hypertension were 12.4% (95% confidence interval (CI): 10.5-14.3) and 34.7% (95% CI: 32.2-37.4), respectively. Systolic and diastolic blood pressures of individuals with and without a lifetime episode of depression were not different after adjustment for age and gender. Lifetime episodic major depression was not associated with hypertension in bivariate analysis (risk ratios (RR): 0.96, 95% CI: 0.76-1.23) and after adjustment for confounding (RR: 1.15; 95% CI:0.75-1.76). Hypertension and depression were not associated in this free-living population of adults, suggesting that their concomitant occurrence in clinical practice may be ascribed to chance.

Blood pressure variability in controlled and uncontrolled blood pressure and its association with left ventricular hypertrophy and diastolic function.

High systolic blood pressure (SBP) variability has been associated with higher risk for target-organ damage. In a cross-sectional study done in a tertiary outpatient hypertension clinic, we compared short-term SBP variability among controlled and uncontrolled hypertensive patients and evaluated the association between higher levels of SBP variability and diastolic function and left ventricular hypertrophy (LVH). Patients were evaluated by 24-h ambulatory blood pressure monitoring and transthoracic Doppler echocardiogram. Blood pressure (BP) variability was evaluated by the time-rate index and high variability corresponded to index values in the top quartile of distribution. Echocardiographic parameters were compared in patients with and without higher BP variability within controlled and uncontrolled office BP (⩽140/90 mm Hg). The analyses included 447 patients with 58±12 years of age, 67% were women, 68% white, 43% current or previous smokers and 32% with diabetes mellitus. Among the whole sample, 137 patients had controlled and 310 uncontrolled BP. The 75th percentile cutoff points for the time-rate index were 0.502 mm Hg min(-1) and 0.576 mm Hg min(-1) for participants with controlled and uncontrolled BP, respectively. After adjustment for confounders, the time-rate index did not differ between controlled and uncontrolled patients. BP variability was not associated with LVH or diastolic function in controlled and uncontrolled BP after adjustment for 24-h SBP and age. Patients with controlled and uncontrolled BP had similar SBP variability assessed by time-rate index, which was not associated with LVH or diastolic function. These findings should be confirmed in studies with larger sample size.

Stopping oral contraceptives: an effective blood pressure-lowering intervention in women with hypertension.

The association of combined oral contraceptives (OC) with higher blood pressure (BP) may be attenuated with pills with smaller doses of oestrogen. The effect of stopping OC on BP of patients with hypertension was not described to date. In a cohort study of patients with hypertension, we identified 72 women using OC among 2112 patients seen from 1989 to 2002. Stopping hormonal contraception was recommended to all. The main outcome measurement was BP change in women who stopped (n=44) and who did not stop (n=28) OC, adjusting for baseline BP and age. Odds ratio for having a reduction of at least 20 mmHg in systolic blood pressure (SBP) or 10 mmHg in diastolic blood pressure (DBP), adjusting for age, change in weight and prescription of BP-lowering drugs, were calculated. The mean follow-up time was 6.6+/-7.5 months. Participants who stopped and did not stop OC had similar baseline characteristics. The deltas of SBP (adjusted) were 15.1+/-2.6 mmHg in patients who stopped and 2.8+/-3.2 mmHg in patients who did not stop OC (P=0.004). The corresponding values for DBP were 10.4+/-1.8 and 2.7+/-2.2 mmHg (P=0.008), respectively. The odds ratio (adjusted) for having a decrease of at least 20 mmHg in SBP or 10 mmHg in DBP was 0.28 (95% CI 0.08-0.90) in patients who stopped OC. Stopping OC is an effective antihypertensive intervention in a clinical setting.

Behavior of ambulatory blood pressure surrounding episodes of headache in mildly hypertensive patients.

BACKGROUND: Headache is usually associated with high blood pressure (BP) despite the lack of evidence of such an association in most observational studies. Ambulatory BP monitoring provides an opportunity to analyze this relation because it permits measurement of BP before, during, and after episodes of headache. METHODS: We evaluated 76 patients with mild hypertension who underwent clinical evaluation, ambulatory BP monitoring, and questioning about the occurrence of headache and its characteristics during monitoring. The 24-hour BP curves of patients with and without headache during monitoring were compared using analysis of variance for multiple factors and repeated measurements. Hourly averages of BP surrounding the episode and 24-hour mean BP of patients with headache were compared using paired sample t tests. RESULTS: Twenty-five participants (33%) experienced headache during monitoring. Their 24-hour BP curves did not differ from those of participants without headache. Mean 24-hour BP was not different from BP registered during the episode of headache (mean +/- SD systolic BP: 137.0 +/- 17.3 vs 139.4 +/- 21.1; P =.13; diastolic BP: 83.3 +/- 12.8 vs 85.0 +/- 18.2; P =.30). Blood pressure values registered during the episode of headache and in the hours before and after the episode were not different from each other. Analysis restricted to 8 patients with migrainelike headache showed a similar pattern. CONCLUSIONS: In patients with mild hypertension, there is no association between the occurrence of headache and variation of BP. Health professionals must discourage patients with hypertension from believing that they can rely on the presence of such a symptom to know about their BP levels.

Seasonal variation in food intake and the interaction effects of sex and age among adults in southern Brazil.

BACKGROUND/OBJECTIVES: Because studies have evidenced variations in nutrient intake, further investigation of the interaction between demographic characteristics and the seasons is necessary. We aimed to test the differences in food intake throughout the seasons and the interaction between the seasons and sex and age. SUBJECTS/METHODS: This study included 273 individuals. Food intake was evaluated with 24-hour dietary recalls, and the reported food items were sorted into food groups. We performed the test on the differences in intake of food groups throughout the seasons with repeated measures and on the interaction effect by using the Generalized Estimate Equation. RESULTS: Intake of fruits and natural fruit juices and sweetened beverages was lower, whereas that of grains and derivatives was higher in the winter. The intake of leafy vegetables and fish and seafood was lower in the autumn. The consumption of coffee and eggs was higher in the spring. Intake of chocolate powder and sugar, salt and lean poultry was higher in the winter. The variation in consumption of grains and derivatives, eggs, fatty poultry and processed meat over the seasons was more likely to be modified by sex. Age interacted with the seasons for leafy vegetables, beans and lentils, lean beef, lean poultry, low fat milk and light yogurt, vegetable oil and unsalted margarine, chocolate powder and sugar and processed meat. CONCLUSIONS: This study shows that food intake may change seasonally and that seasonal variation depends on sex and age, which might aggregate a specific co-variation component.

Alcohol intake and blood pressure: the importance of time elapsed since last drink.

BACKGROUND: A positive association of chronic exposure to alcoholic beverages with blood pressure and the prevalence of hypertension has been described in epidemiological surveys, but the influence of time elapsed since last ingestion in this setting was not demonstrated. DESIGN: A cross-sectional, population-based survey. METHODS: In total 1089 adults from Porto Alegre, randomly selected from a population-based, multi-stage probability sample, were interviewed at home. The average daily alcohol intake of each subject was calculated taking into account the concentration of ethanol in the beverages (distilled or fermented beverages), and the time elapsed between the last ingestion of ethanol and the moment of blood pressure determination. Standardized sitting blood pressure and anthropometric parameters were collected. The magnitude and shape of the associations were analyzed considering blood pressure as a continuous variable and the prevalence of arbitrarily defined hypertension. Simple and multiple linear regression models, including models to identify nonlinear associations, with quadratic and cubic terms of the amount of alcohol consumed, were employed. Blood pressure means were compared by analysis of variance and analysis of covariance. The association between hypertension and exposure to ethanol was analyzed through logistic regression models, controlling for various potential confounders. RESULTS: Positive nonlinear associations of the amount of alcohol consumed with blood pressure and the prevalence of hypertension (> or = 160/95 mmHg) were found, independent of age, years of education, smoking, and use of oral contraceptive and antihypertensive drugs. The consumption of 30 g/day ethanol was associated with increases of 1.5 and 2.3 mmHg in diastolic and systolic blood pressures, respectively, for men, and 2.1 and 3.2 mmHg, respectively, for women. The prevalence of hypertension was higher among those ingesting more than 30 g/day (odds ratio = 2.9, P < 0.01). The time elapsed between the last ingestion and blood pressure measurement was independently associated with the prevalence of hypertension. Men with last consumption of alcohol 13-23 h prior to measurement had odds of being hypertensive 2.6 (confidence interval 1.3-5.0) greater than did subjects who had consumed alcoholic beverages 24 h and more before the blood pressure determination. For men, systolic and diastolic blood pressures were lower during the first 3 h after ingestion and increased afterward. Frequency of consumption and type of beverage consumed were not independently associated with level of blood pressure. CONCLUSION: A time-dependent association between alcohol consumption and effects on blood pressure, demonstrated in experimental studies, was found for free-living individuals selected at random.

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.

The effects of two aerobic training intensities on ambulatory blood pressure in hypertensive patients: results of a randomized trial.

The effect of different intensities of aerobic exercise on blood pressure remains uncertain. The goal of this trial was to compare the effect of two different levels of aerobic physical training on 24-hour ambulatory blood pressure. In this double-blind parallel-group trial, 28 sedentary hypertensive patients (mean diastolic blood pressure of 90 to 104 mm Hg) were randomly assigned to 10 weeks of physical training at 20% (Group I) or 60% (Group II) of their maximal workload on a cycle ergometer (mean load of 32 and 85 watts, respectively). Maximal oxygen consumption was estimated by the time spent on a mechanical braked Monark bicycle (Monark, Sáo Paulo, Brazil). Indexes of physical fitness were determined by cycle ergometer tests before and after the experimental period. The principal outcome variable was mean 24-hour ambulatory blood pressure. Mean 24 hour systolic blood pressure fell from 137.2+/-14.9 to 135.2+/-12.7 mm Hg in Group I and from 144.4+/-13.3 to 138.6+/-12.9 in Group II (mean between group difference of -2.1 mm Hg, P = 0.479, adjusted for baseline blood pressure). Mean diastolic blood pressure fell from 9.21+/-10.0 to 89.3+/-7.7 mm Hg in Group I and from 93.3+/-5.8 to 90.6+/-6.8 mm Hg in Group II (mean adjusted difference of -0.06, P = 0.765). Nighttime blood pressure did not change in either group. Across all participants, a reduction in systolic blood pressure was significantly associated with improved physical fitness as manifest by increased physical work capacity at heart rate of 130 bpm (PWC130), increased systolic blood pressure at PWC130, and decreased maximum heart rate measured during the cycle ergometer test We conclude that aerobic training programs at 20% and 60% of the maximum work capacity have similar effects on ambulatory blood pressure.

Dose-dependent biphasic effect of ethanol on 24-h blood pressure in normotensive subjects.

The vasodilation that follows acute alcohol intake is hard to conciliate with the high prevalence of hypertension detected in those persons who consume regular amounts of alcohol. In this experiment we examined early and late hemodynamic effects of acute administration of water and of 15 g, 30 g, and 60 g of alcohol in 40 normal men, aged 19 to 30 years, using 24-h ambulatory blood pressure monitoring (ABPM). Mean systolic and diastolic blood pressures were each approximately 4 mm Hg lower during the period immediately after ingestion of 60 g (v 0 g) of ethanol, and were 7 and 4 mm Hg higher, respectively, at night. The day minus night differences displayed a dose-response curve both for systolic (P < .001) and diastolic blood pressure (P = .045). Three subjects in the 60-g group had more than 50% of nightly blood pressure loads in the hypertensive range against none in the remaining groups (P < .01). In conclusion, our findings suggest that acute alcohol intake elicits a biphasic hemodynamic response, causing, first, vasodilatation and, later, a pressor effect. The higher prevalence of hypertension in alcohol abusers seen in epidemiological surveys may be, in part, a result of measurements done in the period of transiently increased blood pressure during ethanol washout.

Headache is not more frequent among patients with moderate to severe hypertension.

The association between hypertension and headache has been a contentious issue. Most studies have showed that mild hypertension and headache are not associated, but this may not be the case in patients with hypertension classified at more severe stages. We investigated the association between hypertension classified at moderate to severe stages and headache in a cross-sectional study conducted in the hypertension clinic of a tertiary care University hospital. In total, 1763 referred patients with a medical diagnosis of hypertension in most cases (95.7%) were evaluated by an extensive protocol questionnaire, detailed physical examination, laboratory examination, and had their blood pressure classified according to the VI Joint National Committee (JNC-VI) recommendation. Logistic regression models were used to explore the association between severity of hypertension and pulse pressure with the presence of headache, controlling for several potential confounders. The complaint of headache was referred by 903 (51.3% of whole sample), and a total of 378 patients (21.4%) were classified at the moderate to severe stage (stage III of the JNC-VI report). The diagnosis of moderate to severe hypertension was not associated with the complaint of headache (OR 1.02, 95% CI from 0.79 to 1.30). Pulse pressure and headache were inversely associated (OR 0.91, 95% CI from 0.86 to 0.97, for 10 mmHg). We concluded that headache and hypertension classified at moderate to severe stages were not associated in patients attending to a hypertension clinic. The novel finding of an inverse association between pulse pressure and headache should be addressed in further investigations.

Study of the usefulness of optic fundi examination of patients with hypertension in a clinical setting.

The purpose of this study was to evaluate the usefulness of direct opthalmoscopy by non-opthalmologists in patients with hypertension. In a cross-sectional survey, we analysed the association between optic fundi abnormalities, individually and according to the criteria of Keith and Wagener (KW), with blood pressure and duration of known hypertension in 400 non-diabetic hypertensive patients. The optic fundi abnormalities were more frequent in patients with diastolic blood pressure (DBP) > 105 mm Hg (P = 0.002), SBP > 180 mm Hg (P < 0.0001) and with a duration of known hypertension > 3 years (P = 0.002). The severity of hypertension did not vary in parallel with the KW classes I and II: 34.5% of patients classified as KW I had a diastolic pressure of > 105 mm Hg compared with only 25.3% of those classified as KW II. Class III abnormalities were infrequent (2.5% of the whole cohort). In a logistic regression model, diffuse arteriolar narrowing was associated with DBP (P = 0.002) and age (P < 0.001). Abnormalities of the arteriovenous crossings were associated with SBP (P = 0.001) and duration of disease (P = 0.008). The positive predictive value of any fundoscopic abnormality to estimate the severity of hypertension was 59% and the negative value was 60%. The results of this study demonstrate that optic fundi examination by internists and cardiologists does not give an accurate assessment of the severity of hypertension in most patients, and that the Keith-Wagener classification of retinopathy has a limited applicability.(ABSTRACT TRUNCATED AT 250 WORDS)

Moyamoya disease associated with renovascular disease in a young African-Brazilian patient.

Moyamoya is a rare disease characterized by fibrous dysplasia of the internal carotid and proximal cerebral arteries, which has been described mainly in young Japanese. We present a case of Moyamoya disease with renal artery involvement in a young male patient with an African origin. A 15-year-old boy was referred to our hospital due to uncontrolled blood pressure, headache, somnolence, cognitive deficit and multiple lacunar infarcts in the computed tomography. Cerebral arteriography showed the absence of the normal vascular anatomy at the level of the circle of Willis. The intracranial vessels presented severe stenosis or were occluded and replaced by an extensive network of ectasic collateral vessels. Abdominal ultrasound examination identified asymmetric kidneys, and renal arteriography showed a tight stenosis of the ostium and proximal segment of right main artery, which was only partially relieved by balloon angioplasty. A saphenous bypass from aorta to the right renal artery re-established the renal blood flow. Blood pressure dropped after surgery and was controlled with low doses of diuretic and beta-blocker. After arteriography he presented right hemiplegia, with partial recovering in the following months. In conclusion, we described the first case of Moyamoya disease with concomitant renovascular disease in a young adult of African origin, an association that may be more frequent than usually suspected in clinical practice.

Hypertensive retinopathy and incident coronary heart disease in high risk men.

BACKGROUND/AIM: Although routine ophthalmoscopy is recommended in the evaluation of people with hypertension, the prognostic significance of retinopathy is unknown. The purpose of this study is to determine if hypertensive retinopathy predicts coronary heart disease (CHD). METHODS: A prospective cohort study involving 560 hypertensive, hyperlipidaemic, middle aged men enrolled in the Lipid Research Clinic's Coronary Primary Prevention Trial. Signs of hypertensive retinopathy (generalised and focal arteriolar narrowing, arteriovenous nicking, widened arteriolar light reflex, retinal haemorrhage and exudates, microaneurysms, and disc swelling) were evaluated by direct funduscopy during a baseline examination by study physicians. Incident CHD events were ascertained from hospital records, necropsy reports, and death certificates, and reviewed by a masked panel of cardiologists. RESULTS: There were 51 definite CHD events (definite CHD deaths or myocardial infarctions) during a median follow up of 7.8 years. After adjusting for age, blood pressure, electrocardiographic manifestations of left ventricular hypertrophy, cholesterol levels and treatment, glucose and creatinine levels, and smoking status in proportional hazards analysis, the presence of hypertensive retinopathy predicted a doubling of the risk of definite CHD events (relative risk 2.1; 95% confidence interval (CI) 1.0 to 4.2 ). The presence of either generalised or focal arteriolar narrowing predicted almost a tripling of the risk (relative risk 2.9; 95% CI 1.3 to 6.2). Associations were similar for stage 1 hypertension (systolic and diastolic blood pressures of 140-159 and 90-99 mm Hg, respectively) and for other CHD end points. CONCLUSION: Hypertensive retinopathy predicts CHD in high risk men, independent of blood pressure and CHD risk factors. The data support the concept that retinal microvascular changes are markers of blood pressure damage and may be useful in risk stratification and in the tailoring of hypertension treatment decisions.

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.

Familial predisposition to hypertension and the association between urinary sodium excretion and blood pressure in a population-based sample of young adults.

The reasons for the inconsistent association between salt consumption and blood pressure levels observed in within-society surveys are not known. A total of 157 normotensive subjects aged 18 to 35 years, selected at random in a cross-sectional population-based survey, answered a structured questionnaire. They were classified as strongly predisposed to hypertension when two or more first-degree relatives had a diagnosis of hypertension. Anthropometric parameters were obtained and sitting blood pressure was determined with aneroid sphygmomanometers. Sodium and potassium excretion was measured by flame spectrophotometry in an overnight urine sample. A positive correlation between blood pressure and urinary sodium excretion was detected only in the group of individuals strongly predisposed to hypertension, both for systolic blood pressure (r = 0.51, P<0.01) and diastolic blood pressure (r = 0.50, P<0.01). In a covariance analysis, after controlling for age, skin color and body mass index, individuals strongly predisposed to hypertension who excreted amounts of sodium above the median of the entire sample had higher systolic and diastolic blood pressure than subjects classified into the remaining conditions. The influence of familial predisposition to hypertension on the association between salt intake and blood pressure may be an additional explanation for the weak association between urinary sodium excretion and blood pressure observed in within-population studies, since it can influence the association between salt consumption and blood pressure in some but not all inhabitants.

Effect of sodium intake on blood pressure, serum levels and renal excretion of sodium and potassium in normotensives with and without familial predisposition to hypertension.

1. Seventeen normal volunteers aged 19 to 22 were randomly subjected, in a trial of crossover design, to three distinct regimens of sodium chloride intake: high (16 to 20 g), normal (8 to 12 g) and low (0.5 to 1 g). Each regimen lasted nine days, with determination of blood pressure and heart rate (in the supine position and after sudden rising), body weight, and urinary output of creatinine, sodium and potassium on the third, sixth and ninth days. In addition, plasma levels of creatinine, sodium and potassium were determined on the ninth day so that sodium and potassium clearance and fractional excretion could be calculated. 2. Eleven of the volunteers had a family history of hypertension. Compared to the six without such a history, these subjects showed: 1) higher supine systolic blood pressure on the third day of sodium overload (124.7 +/- 3.0 vs 112.3 +/- 2.9 mmHg, P less than 0.02); 2) higher supine diastolic blood pressure on the third day of sodium overload (76.5 +/- 2.8 vs 64.5 +/- 4.3 mmHg; P less than 0.05); 3) higher supine diastolic blood pressure on the sixth day of sodium overload (73.7 +/- 2.3 vs 63.8 +/- 3.2 mmHg, P less than 0.05); 4) lower supine heart rate on the ninth day of sodium overload (61.0 +/- 3.1 vs 72.7 +/- 4.6, P less than 0.05), and 5) lower plasma potassium on the ninth day of sodium overload (4.10 +/- 0.05 vs 4.28 +/- 0.06 mEq/l, P less than 0.05). 3. These results suggest that normal individuals whose familial history places them at risk for the development of hypertension differ from those not at risk during their adaptation to sodium load by suffering a transient elevation of blood pressure within a few days of the increase in load. The low levels of plasma potassium observed in these volunteers after a period of sodium load may be due to the operation of different renal mechanisms of sodium excretion in this group, leading to increased kaliuresis, and may explain the high vascular reactivity of such individuals.

Alcoholic beverage consumption and associated factors in Porto Alegre, a southern Brazilian city: a population-based survey.

OBJECTIVE: To describe the pattern of alcoholic beverage consumption and the prevalence of at risk drinking behaviors, as well as their association with demographic and socioeconomic factors in the adult population of Porto Alegre, a southern Brazilian city. METHOD: In a cross-sectional, population-based, multistage random sampling study, 1,091 (600 female) individuals (92% of those eligible) were selected and interviewed at home. Exposure to alcohol was measured by the CAGE questionnaire and by inquiring about the type, quantity and frequency of alcoholic beverage consumption. An average consumption of 30 g per day or more, a level of exposure associated with health risks, was considered as heavy drinking. Two positive answers to the GAGE questionnaire represented the cutoff for indicating dependence. RESULTS: The prevalences were: 9.3% (95% CI: 7.6 to 11.0) for dependence, 15.5% (13.4 to 17.7) for heavy drinking and 12.3% (10.4 to 14.2) for daily drinking; 24.1% (21.7 to 26.6) were abstinent. Women consumed alcoholic beverages in lower frequency and amounts than men. The most widely consumed beverages were beer, wine and "cachaça," a Brazilian sugarcane spirit. In a logistic regression model, increasing age, lower education and income, and nonwhite race were associated with heavy drinking and dependence. Households with 3-4 persons were associated with the lowest risk of heavy drinking, but the prevalence of dependence was higher in crowded households. The presence of another heavy drinker or dependent in the household was associated with heavy drinking but not with dependence. CONCLUSIONS: The study characterized a detailed pattern of alcoholic beverage use and indicated that at risk drinking is an important public health problem in a developing country. The risk factors for heavy drinking and dependence were the same, with the exception of age at starting to drink, heavy drinking or dependence-positive household members.

The effect of Syzygium cumini (L.) skeels on post-prandial blood glucose levels in non-diabetic rats and rats with streptozotocin-induced diabetes mellitus.

This study was undertaken to investigate whether a tea prepared from Syzygium cumini, reported to be used by diabetics in Porto Alegre, Brazil, might have an antihyperglycemic effect in experimental models. Teas prepared from leaves and seeds of S. cumini, in concentrations ranging from 2-64 g/l, were administered, as water substitute for 14-95 days, to 16 groups with 8-9 normal albino rats and to four groups with 10-12 rats with streptozotocin-induced diabetes mellitus. Post-prandial blood glucose levels were determined by the glucose oxidase method on blood samples obtained by decapitation. None of the tea concentration had any detectable antihyperglycemic effect either in normal or in diabetic rats, suggesting that this plant, prepared in a manner similar to that employed by humans, is destitute of an antihyperglycemic effect.