Incidence of hypertension in Porto Alegre, Brazil: a population-based study

How Do Young and Old Spontaneously Hypertensive Rats Respond to Antihypertensive Therapy? Comparative Studies on the Effects of Combined Captopril and Nifedipine Treatment

Numerous studies on the effects of antihypertensive treatment in young spontaneously hypertensive rats (SHRs) have shown that early-onset therapy may effectively reduce their blood pressure (BP) even to normotensive values. In contrast, only a few studies investigated the effects of treatment started at an advanced age. These studies revealed that antihypertensive effects are lower in adult or even in senescent SHRs compared with young SHRs. Even more, prevention of cardiac sequelae of hypertension such as hypertrophy and fibrosis is less effective when treatment starts late in life. Because, in patients, combination therapies with calcium antagonists are favored, we studied the efficacy of a combination therapy with captopril and nifedipine in young and old SHRs. We directly compared the treatment effects on BP as well as on cardiac hypertrophy and remodeling between these two animal cohorts. With antihypertensive treatment, significantly lower BP values were achieved in young SHRs despite a shorter treatment period compared with old SHRs. Although treatment effects on cardiac hypertrophy were greater in old than in young SHRs, cardiac fibrosis was significantly attenuated only in young but not in old SHRs. The results emphasize the value of antihypertensive therapy and particularly accentuate the importance of an early-onset therapy. With respect to problems such as late diagnosis and poor therapy adherence, these results may have great importance for the treatment of human hypertension.

The 10-year incidence of hypertension across blood pressure categories in a population-based cohort in southwestern Sweden

BACKGROUND

To explore the determinants of incident hypertension, and especially the impact of baseline blood pressure categories, in a representative Swedish population.

METHODS

A 10-year longitudinal study of residents aged 30-74. Blood pressures were measured and categorized according to ESH guidelines with optimal blood pressure < 120/80 mmHg, normal 120-129/80-84 mmHg, and high normal 130-139/85-89 mmHg. Incident hypertension was defined as ongoing treatment or three consecutive blood pressure readings ≥ 140/ ≥ 90 mmHg (one or both) at follow-up, while those with ≥ 140 and/or ≥ 90 mmHg at only one or two visits were labelled as unstable. After excluding subjects with hypertension, ongoing blood pressure lowering medication or a previous CVD event at baseline, 1099 remained for further analyses.

RESULTS

Sixteen (2.6%) subjects with optimal baseline blood pressure had hypertension at follow up. Corresponding numbers for subjects with normal, high normal and unstable blood pressure were 55 (19.4%), 50 (39.1%) and 46 (74.2%), respectively. Compared with subjects in optimal group those in normal, high normal and unstable blood pressure categories had significantly higher risk to develop manifest hypertension with odds ratios OR and (95% CI) of 7.04 (3.89-12.7), 17.1 (8.88-33.0) and 84.2 (37.4-190), respectively, with adjustment for age, BMI and family history for hypertension. The progression to hypertension was also independently predicted by BMI (p < 0.001), however, not by age.

CONCLUSIONS

Subjects with high normal or unstable blood pressure should be identified in clinical practice, evaluated for global hypertension risk and offered personalized advice on lifestyle modification for early prevention of manifest hypertension and cardiovascular disease.

Effects of recreational sports and combined training on blood pressure and glycated hemoglobin in middle-aged and older adults: A systematic review with meta-analysis

BACKGROUND

Combined resistance and aerobic training (CT) is the most suitable form of exercise training to simultaneously improve strength and cardiometabolic profile in middle-aged and older adults. Recreational sports (RS) emerge as an alternative to CT to improve these outcomes. We performed a meta-analysis on the effects of RS and CT on systolic blood pressure (SBP), diastolic blood pressure (DBP) and glycated hemoglobin (HbA1c) in middle-aged and older adults and to compare these exercise interventions to a non-exercising control group (CON).

METHODS

Search was conducted using the databases at PubMed, COCHRANE and SciELO between July and August 2020. Studies that included men and women aged ≥45 years, healthy or with values for SBP ≥130 mmHg or DBP ≥80 mmHg or with type 2 diabetes and performed RS or CT versus CON.

RESULTS

From 6017 records, 27 studies were included (9 RS and 18 CT). The analysis included 1411 participants with 55 ± 8 years. RS and CT were associated with reductions in SBP (RS: -7.2 mmHg, P = 0.03; CT: -3.6 mmHg, P < 0.001) and DBP (RS: -3.6 mmHg, P = 0.02; CT: -3.1 mmHg, P < 0.001) versus CON. Only CT was associated with a reduction in HbA1c versus CON (-0.47%; P < 0.001).

CONCLUSIONS

RS and CT are effective exercise interventions to improve BP in middle-aged and older adults. CT seems to be an excellent strategy to reduce HbA1c, and future studies are necessary to confirm the effectiveness of RS to improve HbA1c.

Efficacy of Khār-i-khasak (Tribulus terrestris Linn.) in prehypertension: a randomized, double-blind, placebo-controlled trial

BACKGROUND

Prehypertension is a state of above-normal blood pressure that does not meet the criteria for the diagnosis of hypertension and its prevalence estimated in population-based samples ranges from 22 to 52%. It conveys potentially many deleterious consequences such as high risk of progression to hypertension and cardiovascular disease later in life.

OBJECTIVES

The present study was conducted to evaluate the blood pressure-lowering effect of Khār-i-khasak (Tribulus terrestris Linn.) in prehypertensive individuals.

METHODS

This randomized, double-blind, placebo-controlled, clinical trial was conducted at the National Institute of Unani Medicine, Hospital, Bengaluru, after approval by the Institutional Ethics Committee. Prehypertensive individuals over 18 years of age were enrolled after obtaining their written informed consent and were randomly allocated to the test or placebo group. The test and placebo groups were administered powdered dried fruits of Khār-i-khasak (6g) and matched placebo (6g) in three divided doses for two months respectively. The efficacy assessment was determined by changes in systolic and diastolic blood pressures.

RESULTS

Both systolic and diastolic blood pressure showed a significant decline in the test group (p<0.001) as compared to the placebo group. The average decline in systolic/diastolic blood pressure was -7.7/5.5 mmHg in the test group and -1.9/0.2 mmHg in the placebo group. During the post-therapy follow-up period, no prehypertensive developed full-blown hypertension in either group. Safety parameters were found to be within normal limits.

CONCLUSIONS

The test drug Khār-i-khasak (T. terrestris Linn.) was found to be effective and safe in lowering blood pressure compared to placebo in prehypertensive individuals.

Incidence of hypertension among Asian Indians: 10 year follow up of the Chennai Urban Rural Epidemiology Study (CURES-153)

AIMS

There are very few studies on incidence of hypertension from developing countries. We report on the incidence of hypertension and its risk factors in Chennai city in southern India.

METHODS

Participants were 1691 individuals from the Chennai Urban Rural Epidemiology Study (CURES) cohorts who did not have hypertension (normotensive n = 878, prehypertension n = 813) at baseline and who were followed for a median of 9.0 years. During the follow-up, 41 with missing blood pressure values were excluded, leaving 1650 individuals for the present analysis. Incidence rates of hypertension and predictors of progression to prehypertension and/or hypertension were estimated using Cox proportional hazards model.

RESULTS

During the follow-up period, 426 out of 1650 individuals developed hypertension, giving an overall incidence of hypertension of 28.7(95%CI 26.1-31.5) per 1000 person-years. Individuals with dysglycemia at baseline had higher incident rates of hypertension. Collectively, four modifiable risk factors [pre-hypertension, dysglycemia, central obesity and physical inactivity] accounted for 87.2% of the population attributable risk of incident hypertension.

CONCLUSIONS

Higher body weight, BMI, age and dysglycemia were associated with an increased risk of incident hypertension. Prehypertension, dysglycemia, central obesity and physical inactivity accounted for 87% of incident hypertension.

The management of prehypertension in young adults

The incidence of prehypertension (blood pressure 120-139 and/or 80-89 mm Hg) in young adults worldwide ranges from ~37.5% to 77.1%. Identifying high-risk groups of prehypertension in young adults is helpful for early and effective interventions and treatments to reduce the occurrence of future hypertension and organ damage. This review summarized the epidemiological characteristics, disease intervention measures, and disease progression characteristics of prehypertension to provide a basis for the development of targeted intervention measures for young adults with prehypertension.

High Blood Pressure and Cardiovascular Disease

Fragmented investigation has masked the overall picture for causes of cardiovascular disease (CVD). Among the risk factors for CVD, high blood pressure (BP) is associated with the strongest evidence for causation and it has a high prevalence of exposure. Biologically, normal levels of BP are considerably lower than what has typically been characterized as normal in research and clinical practice. We propose that CVD is primarily caused by a right-sided shift in the population distribution of BP. Our view that BP is the predominant risk factor for CVD is based on conceptual postulates that have been tested in observational investigations and clinical trials. Large cohort studies have demonstrated that high BP is an important risk factor for heart failure, atrial fibrillation, chronic kidney disease, heart valve diseases, aortic syndromes, and dementia, in addition to coronary heart disease and stroke. In multivariate modeling, the presumed attributable risk of high BP for stroke and coronary heart disease has increased steadily with progressive use of lower values for normal BP. Meta-analysis of BP-lowering randomized controlled trials has demonstrated a benefit which is almost identical to that predicted from BP risk relationships in cohort studies. Prevention of age-related increases in BP would, in large part, reduce the vascular consequences usually attributed to aging, and together with intensive treatment of established hypertension would eliminate a large proportion of the population burden of BP-related CVD.

Effectiveness of low-dose diuretics for blood pressure reduction to optimal values in prehypertension: a randomized clinical trial

BACKGROUND

To determine the effectiveness of low-dose diuretic therapy to achieve an optimal level of blood pressure (BP) in adults with prehypertension.

METHODS

The PREVER-prevention trial was a randomized, parallel, double-blinded, placebo-controlled trial, with 18 months of follow-up, conducted at 21 academic medical centers in Brazil. Of 1772 individuals evaluated for eligibility, 730 volunteers with prehypertension who were aged 30-70 years, and who did not reach optimal blood pressure after 3 months of lifestyle intervention, were randomized to a fixed association of chlorthalidone 12.5 mg and amiloride 2.5 mg or placebo once a day. The main outcomes were the percentage of participants who achieved an optimal level of BP.

RESULTS

A total of 372 participants were randomly allocated to diuretics and 358 to placebo. After 18 months of treatment, optimal BP was noted in 25.6% of the diuretic group and 19.3% in the placebo group (P < 0.05). The mean net reduction in SBP and DBP for the diuretic group compared with placebo was 2.8 mmHg (95% CI 1.1 to 4.5) and 1.1 mmHg (95% CI -0.09 to 2.4), respectively. Most participants in the active treatment group (74.5%) and in the placebo group (80.7%) continued to have BP in the prehypertension range or progressed to hypertension.

CONCLUSION

Low-dose diuretic therapy increased the probability of individuals with prehypertension to achieve optimal BP but most of those treated continued to have a BP in the prehypertension range or progressed to having overt hypertension.

Incidence of cardiovascular risk factors in female patients with systemic lupus erythematosus: a 3-year follow-up cohort

Objectives

To evaluate the incidence and variability of traditional coronary artery disease (CAD) risk factors in a cohort of lupus patients and to investigate if prednisone use predicts an increase in the number of risk factors.

Methods

A total of 151 women, 37.8 ± 11.1 (mean ± SD) years old at baseline, were reevaluated after a median period of 39 (interquartile range 36.5–42.0) months. The cumulative incidence of traditional risk factors, the incidence rate (with 95% confidence interval) of hypertension, diabetes, dyslipidemia and hypertriglyceridemia, and the frequency of the risk factors’ disappearance were calculated. Metabolic syndrome (MetS) and Framingham risk score (FRS) were computed. Logistic regression was used to investigate if maximum or cumulative prednisone dose used during follow-up predicted an increase in the cardiometabolic risk factors’ number.

Results

The cumulative incidence of risk factors varied from 39.1% (abdominal obesity) to zero (smoking), and the incidence rate varied from 133.2 (87.8–178.6) per 1000 person-years (dyslipidemia) to 10.4 (1.3–19.5) per 1000 person-years (diabetes). The cumulative incidence for MetS was 18.8%, and 11.7% of 143 patients with low FRS at baseline (T1) were classified in the high-risk category at the end of the study (T2). Dyslipidemia was the most variable risk factor, with 43.5% disappearance at T2. The maximum prednisone dose used during follow-up was borderline ( p = 0.050) for prediction of an increase in the number of cardiometabolic risk factors in an adjusted model for antimalarial use, modified Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) and age.

Conclusion

The authors described high incidence and variability of CAD risk factors in female lupus patients, with higher prednisone dose being borderline for an increase in the number of cardiometabolic risk factors.

Association of prehypertension and cardiovascular risk factor clustering in Inner Mongolia: a cross-sectional study

OBJECTIVES

To assess the clustering of cardiovascular disease (CVD) risk factors in Han and Mongolian adults with prehypertension or hypertension in Northern China.

METHODS

We selected 3227 Han and Mongolian participants (20-80 years old) using a multistage cluster sampling method in 2014. The participants were interviewed by standard questionnaires and underwent anthropometric measurement and biochemical testing. Han and Mongolian participants were divided into optimal, prehypertension, and hypertension groups based on blood pressure. A multinomial logit analysis was performed to explore relationships between CVD risk factor clustering and prehypertension or hypertension, and the heterogeneity between Han and Mongolian was evaluated by the Cochran Q test. The differences between the ethnic groups in the proportions of risk factors was tested with the χ² test.

RESULTS

The clustering of two or three CVD risk factors in the prehypertension or hypertension groups was consistently higher than in the optimal group (Bonferroni, p<0.0167). The odds ratios (ORs) of prehypertension and hypertension increased with the number of CVD risk factors (p_trend <0.0001). In multivariate modelling, the adjusted ORs of one, two, and ≥3 CVD risk factors versus no risk factors was, respectively, 1.95, 2.25, and 2.28 in Han prehypertensive participants, and 1.73, 2.83, and 3.69 in Mongolian prehypertensive participants. In addition, the adjusted ORs were 3.15, 4.75, and 6.49 in Han hypertensive participants, and 1.90, 5.29, and 8.13 in Mongolian hypertensive participants (all p<0.05). There was no significant heterogeneity between Han and Mongolian participants in the prehypertension or hypertension groups. The age-standardised prevalence of ≥3 risk factors was 38.30% in Han men and 39.79% in Mongolian men. The rate was significantly lower in Han women than Mongolian women (9.18% vs 14.55%, p=0.002).

CONCLUSIONS

These findings showed clustering of CVD risk factors in prehypertensive Han and Mongolian adults, and showed prehypertension may be a useful target for intervention.

Effectiveness of Chlorthalidone Plus Amiloride for the Prevention of Hypertension: The PREVER-Prevention Randomized Clinical Trial

BACKGROUND

Prehypertension is associated with higher cardiovascular risk, target organ damage, and incidence of hypertension. The Prevention of Hypertension in Patients with PreHypertension (PREVER-Prevention) trial aimed to evaluate the efficacy and safety of a low-dose diuretic for the prevention of hypertension and end-organ damage.

METHODS AND RESULTS

This randomized, parallel, double-blind, placebo-controlled trial was conducted in 21 Brazilian academic medical centers. Participants with prehypertension who were aged 30 to 70 years and who did not reach optimal blood pressure after 3 months of lifestyle intervention were randomized to a chlorthalidone/amiloride combination pill or placebo and were evaluated every 3 months during 18 months of treatment. The primary outcome was incidence of hypertension. Development or worsening of microalbuminuria, new-onset diabetes mellitus, and reduction of left ventricular mass were secondary outcomes. Participant characteristics were evenly distributed by trial arms. The incidence of hypertension was significantly lower in 372 study participants allocated to diuretics compared with 358 allocated to placebo (hazard ratio 0.56, 95% CI 0.38-0.82), resulting in a cumulative incidence of 11.7% in the diuretic arm versus 19.5% in the placebo arm (P=0.004). Adverse events; levels of blood glucose, glycosylated hemoglobin, creatinine, and microalbuminuria; and incidence of diabetes mellitus were no different between the 2 arms. Left ventricular mass assessed through Sokolow-Lyon voltage and voltage-duration product decreased to a greater extent in participants allocated to diuretic therapy compared with placebo (P=0.02).

CONCLUSIONS

A combination of low-dose chlorthalidone and amiloride effectively reduces the risk of incident hypertension and beneficially affects left ventricular mass in patients with prehypertension.

CLINICAL TRIAL REGISTRATION

URL: http://www.ClinicalTrials.gov, www.ensaiosclinicos.gov. Unique identifiers: NCT00970931, RBR-74rr6s.

Anthropometric measures change and incidence of high blood pressure levels among adults: a population-based prospective study in Southern Brazil

OBJECTIVE

The objective was to evaluate the effects of BMI and waist circumference change on the cumulative incidence of high blood pressure levels (HBP) among adults.

METHODS

Prospective longitudinal study in Southern Brazil, with a sample evaluated in 2009 (n = 1720) and 2012 (n = 1213). The incidence of HBP was estimated using measured values of systolic and diastolic arterial pressure (≥140/90 mmHg).

RESULTS

The prevalence of overweight (BMI ≥ 25 kg/m) was 47.3% in 2009 and 55.0% in 2012. The incidence of HBP was 32.0%. Being overweight or having an elevated waist circumference (top quartile) in the two waves increased the incidence of HBP [odds ratio 3.41 (95% confidence interval (CI) 2.10; 5.53) and 5.42 (95% CI 2.65; 11.08), respectively] compared with those always eutrophic. Being overweight in either wave also increased the risk of HBP, whereas reducing waist circumference was a protective factor. When the annual BMI and waist circumference change were evaluated (conditional to the baseline measurements, age, and sex) the adjusted predicted incidence of HBP was 46.5% (95% CI 36.9; 56.1) among individuals with an annual BMI change more than +1.0 kg/m, and 45.1% (95% CI 36.7; 53.4) among those with an annual waist circumference change more than +3.0 cm. Among those who reduced their BMI and waist circumference, the incidence of HBP were 25.9 and 23.8%, respectively.

CONCLUSION

Being overweight (in any wave), maintaining an elevated waist circumference, or having an annual rise of these measurements above the expected values, all increased the incidence of HBP. Reducing the waist circumference showed greater benefits for the prevention of HBP than BMI changes.

A Meta-Analysis on Prehypertension and Chronic Kidney Disease

Background

Recent studies have demonstrated that there is an association between prehypertension and an increased risk of end-stage renal disease. However, there is conflicting evidence regarding the relationship between prehypertension and chronic kidney disease (CKD). This meta-analysis aimed to demonstrate the association between prehypertension and the incidence of CKD and identify the impacts of gender and ethnic differences.

Methods

MEDLINE, EMBASE, Cochrane Library (from inception through March 2016) and article reference lists were searched for relevant studies regarding blood pressure and CKD. Blood pressure (BP) measurements were classified as follows: optimal BP (less than 120/80 mmHg), prehypertension (120-139/80-89 mmHg) and hypertension (over 140/90 mmHg). CKD was defined by estimated glomerular filtration rate (eGFR)<60 ml/min/1.73 m² or proteinuria. Two investigators independently extracted the data and assessed the quality of studies enrolled in this meta-analysis using the Newcastle-Ottawa Scale (NOS). We performed the meta-analysis using Stata/SE 12.0 (StataCorp LP). The random-effect models were used in the heterogeneous analyses.

Results

After retrieving data from 4,537 potentially relevant articles, we identified 7 cohort studies including 261,264 subjects, according to the predefined selection criteria. Five studies were conducted in Mongolians from East Asia, and the other two studies were performed in Indo-Europeans from Austria and Iran. The participants ranged in age from 20 to 89 years, and the proportion of females ranged from 27.2% to 63.8%. The follow-up period ranged from 2 to 11 years. Compared with the optimal BP values, prehypertension showed an increased risk of CKD (pooled RR = 1.28; 95% CI = 1.13–1.44; P = 0.000; I² = 77.9%). In the sex-stratified analysis, we found a similar trend in women (pooled RR = 1.29; 95% CI = 1.01–1.63; P = 0.039; I² = 76.1%) but not in men. This effect was observed only in Mongolians from East Asia (pooled RR = 1.37; 95% CI = 1.18–1.59; P = 0.000; I² = 81.3%) and not in Indo-Europeans.

Conclusions

Prehypertension is considered a potential cause of CKD. Gender and ethnic differences are exhibited in this association.

Preventing the progression of prehypertension to hypertension: role of antihypertensives

Recent guidelines for the diagnosis and management of hypertension reversed the historical trend to recommend lower blood pressure (BP) thresholds to diagnose hypertension in high-risk individuals, such as patients with diabetes and elderly patients. The decision to raise the BP thresholds for diagnosis of hypertension in patients with diabetes was mostly based on the findings of the ACCORD trial. Nonetheless, the results of the ACCORD trial are within the predicted benefit to prevent coronary artery disease and stroke by meta-analysis of randomized controlled trials (RCT), particularly in regard to the prevention of stroke. The Eighth Joint National Committee (JNC 8) did not address prehypertension. There are many RCT done in individuals with prehypertension and concomitant cardiovascular disease showing the benefit of treatment of these patients. Trials exploring the efficacy of interventions to prevent cardiovascular disease in individuals with prehypertension free of cardiovascular disease would be hardly feasible in face of the low absolute risk of these individuals. Considering the risks of prehypertension for cardiovascular disease and the fast progression to hypertension of a large proportion of individuals with prehypertension, it is worth to consider drug treatment for individuals with prehypertension. RCT showed that the progression to hypertension can be partially halted by BP-lowering agents. These and ongoing clinical trials are herein revised. Prehypertension may be a window of opportunity to prevent hypertension and its cardiovascular consequences.

Incidence of hypertension in a prospective cohort study of adults from Porto, Portugal

Background

During the past 30 years, Portugal has been described as one of the countries with highest median blood pressure levels in Europe, but the incidence of hypertension is unknown. The aim of this study was to estimate the incidence of hypertension, according to socio-demographic characteristics and lifestyles.

Methods

A population-based cohort of randomly selected dwellers from Porto, Portugal, aged ≥18 years, was assembled in 1999–2003 (EPIPorto study) and 796 hypertension-free individuals (62.6% women) were reassessed after a median of 3.8 years. Hypertension was defined as blood pressure ≥140/90 mmHg and/or antihypertensive drug therapy. Incidence rate ratios (IRR) were estimated using Poisson regression.

Results

The overall incidence rate was 47.3 [95% confidence interval (95% CI): 40.5-55.5] per 1000 person-years. Among women, the incidence was 43.4 (35.6-53.1) and among men 52.7 (41.3-68.0) per 1000 person-years. The incidence was lower in women up to 60 years and much higher among women above 60 (110.0 vs. 64.4 per 1000 person-years among men, p for age-sex interaction=0.032). Participants with higher education had a lower risk of becoming hypertensive (≥13 years vs. ≤4 years: RR=0.70, 95% CI, 0.46-1.08, p for linear trend <0.001), independently of age and sex. Overweight and obesity were associated with a 1.67-fold and 2.44-fold increased risk of hypertension, respectively, independently of age, sex and education.

Conclusions

In this urban Portuguese population the incidence rate of hypertension was high, with new cases occurring predominantly among older subjects, the less educated and those with overweight-obesity. Despite recent progresses in blood pressure related outcomes, the risk of hypertension remains higher in Portugal than in other developed countries.

Incidence of hypertension and its risk factors in rural Kerala, India: a community-based cohort study

OBJECTIVES

To investigate the incidence of hypertension and its risk factors in Kerala, India where the epidemiological transition is more advanced than elsewhere in India.

STUDY DESIGN

Prospective cohort study.

METHODS

A sample of 297 individuals (aged 15-64 years) in rural Kerala, India, who were free of hypertension at study enrolment, were followed-up from 2003 to 2010. At enrolment, demographic characteristics and behavioural risk factors were determined by interview, and the participants underwent physical (blood pressure, height, weight and waist circumference) and biochemical examinations (fasting plasma glucose and serum lipids). At follow-up, blood pressure readings were repeated using the original tool following the same protocol.

RESULTS

Nearly one-quarter (23.6%) of the sample developed hypertension over a mean follow-up period of 7.1 (standard deviation 0.2) years. Age ≥35 years [relative risk (RR) 4.00, 95% confidence interval (CI) 2.37-6.03], current smoking [RR 1.99, 95% CI 1.14-2.97, population-attributable risk percent (PAR%) 13.3%], high-normal blood pressure (RR 3.53 vs optimal blood pressure, 95% CI 2.17-5.28, PAR% 44.0%) and central obesity (RR 2.45, 95% CI 1.45-3.70, PAR% 40.4%) were significantly associated with incident hypertension. Collectively, current smoking, high-normal blood pressure and central obesity accounted for 70.1% of all new cases of hypertension. Awareness, treatment and control rates of incident hypertension were 42.9%, 22.9% and 11.4%, respectively.

CONCLUSIONS

This rural sample showed a high incidence of hypertension. This underscores the need for primary prevention of hypertension through lifestyle modification strategies targeting individuals with high-normal blood pressure, central obesity and current smoking. The healthcare system needs to improve the level of awareness, treatment and control of hypertension in this population.

Prevention of hypertension in patients with pre-hypertension: protocol for the PREVER-prevention trial

Background

Blood pressure (BP) within pre-hypertensive levels confers higher cardiovascular risk and is an intermediate stage for full hypertension, which develops in an annual rate of 7 out of 100 individuals with 40 to 50 years of age. Non-drug interventions to prevent hypertension have had low effectiveness. In individuals with previous cardiovascular disease or diabetes, the use of BP-lowering agents reduces the incidence of major cardiovascular events. In the absence of higher baseline risk, the use of BP agents reduces the incidence of hypertension. The PREVER-prevention trial aims to investigate the efficacy, safety and feasibility of a population-based intervention to prevent the incidence of hypertension and the development of target-organ damage.

Methods

This is a randomized, double-blind, placebo-controlled clinical trial, with participants aged 30 to 70 years, with pre-hypertension. The trial arms will be chlorthalidone 12.5 mg plus amiloride 2.5 mg or identical placebo. The primary outcomes will be the incidence of hypertension, adverse events and development or worsening of microalbuminuria and of left ventricular hypertrophy in the EKG. The secondary outcomes will be fatal or non-fatal cardiovascular events: myocardial infarction, stroke, heart failure, evidence of new sub-clinical atherosclerosis, and sudden death. The study will last 18 months. The sample size was calculated on the basis of an incidence of hypertension of 14% in the control group, a size effect of 40%, power of 85% and P alpha of 5%, resulting in 625 participants per group. The project was approved by the Ethics committee of each participating institution.

Discussion

The early use of blood pressure-lowering drugs, particularly diuretics, which act on the main mechanism of blood pressure rising with age, may prevent cardiovascular events and the incidence of hypertension in individuals with hypertension. If this intervention shows to be effective and safe in a population-based perspective, it could be the basis for an innovative public health program to prevent hypertension in Brazil.

Trial Registration

Clinical Trials NCT00970931.

Prehypertension: the rationale for early drug therapy

Blood pressure within prehypertensive levels confers higher cardiovascular risk by two means. At first, these levels are associated with higher risk for cardiovascular events, starting at BP values as low as 115/75 mmHg, and doubling at each 20 mmHg for systolic or 10 mmHg for diastolic BP. Prehypertension is also an intermediate stage for full hypertension, which develops in an annual rate of 7 out 100 individuals with 40-50 years of age. The precocious drug intervention in patients with prehypertension is therefore appealing. In individuals with previous cardiovascular disease or diabetes the use of BP-lowering agents is compulsory, since the 18-42% reduction of major cardiovascular events demonstrated in randomized clinical trials translates in palpable clinical benefit. In the absence of higher baseline risk, the absolute benefit of treatment is presumably small and was not demonstrated to date. These individuals could be candidate to treatment with the aim to prevent the development of full hypertension. The long-lasting effectiveness of non-drug therapies is low outside the controlled conditions of randomized clinical trials, and there are evidences that the use of BP-lowering drugs reduces the incidence of hypertension in individuals with prehypertension by more than 60%. Clinical trials testing the efficacy and safety of BP agents to prevent hypertension in a population-based perspective are required. In the meantime, it is worthy to present the option to start low doses of BP agents for individuals with prehypertension without co-morbidities who do not respond to the prescription of lifestyle modification.

Dyslipidemia and the risk of incident hypertension in a population of community-dwelling Brazilian elderly: the Bambuí cohort study of aging

This study aimed to examine the prognostic value of lipid parameters for incident hypertension in elderly living in a community. The study included 306 (81% from total) persons aged > 60 years who were free of hypertension and of cardiovascular diseases at the baseline survey of the Bambuí Cohort Study of Aging. The cumulative incidence of hypertension over three years was 37.3%. The relative risk (RR) of incident hypertension decreased 0.92 for each unit of HDL-cholesterol (95%CI: 0.86-0.99) independent of several potential confounding factors. Individuals with HDL-cholesterol in the top tercile (> 55mg/dL) had a risk of hypertension halve that those in the bottom tercile (RR = 0.54; 95%CI: 0.33-0.90). Other lipid parameters had no significant effect on the outcome. High HDL-cholesterol showed an independent protective effect on subsequent development of hypertension in the elderly.

The corporate bias and the molding of prescription practices: the case of hypertension

Drug management of hypertension has been a noticeable example of the influence of the pharmaceutical industry on prescription practices. The worldwide leading brands of blood pressure-lowering agents are angiotensin receptor-blocking agents, although they are considered to be simply substitutes of angiotensin-converting enzyme (ACE) inhibitors. Commercial strategies have been based on the results of clinical trials sponsored by drug companies. Most of them presented distortions in their planning, presentation or interpretation that favored the drugs from the sponsor, i.e., corporate bias. Atenolol, an ineffective blood pressure agent in elderly individuals, was the comparator drug in several trials. In a re-analysis of the INSIGHT trial, deaths appeared to have been counted twice. The LIFE trial appears in the title of more than 120 reproductions of the main and flawed trial, as a massive strategy of scientific marketing. Most guidelines have incorporated the corporate bias from the original studies, and the evidence from better designed studies, such as the ALLHAT trial, have been largely ignored. In trials published recently corporate influences have touched on ethical limits. In the ADVANCE trial, elderly patients with type 2 diabetes and cardiovascular disease or risk factors, allocated to placebo, were not allowed to use diuretic and full doses of an ACE inhibitor, despite the sound evidence of benefit demonstrated in previous trials. As a consequence, they had a 14% higher mortality rate than the participants allocated to the active treatment arm. This reality should be modified immediately, and a greater independence of the academy from the pharmaceutical industry is necessary.