Daily calcium intake and its relation to blood pressure, blood lipids, and oxidative stress biomarkers in hypertensive and normotensive subjects

Several studies revealed that low calcium intake is related to high prevalence of cardiovascular diseases such as hypertension. The prevalence of hypertension is high in Koreans along with their low dietary calcium consumption. Thus, the aim of this study was to evaluate the status of calcium intake between the hypertension and normotension groups and to investigate the correlation between dietary calcium intake and blood pressure, blood lipid parameters, and blood/urine oxidative stress indices. A total of 166 adult subjects participated in this study and were assigned to one of two study groups: a hypertension group (n = 83) who had 140 mmHg or higher in systolic blood pressure (SBP) or 90 mmHg or higher in diastolic blood pressure (DBP), and an age- and sex-matched normotension group (n = 83, 120 mmHg or less SBP and 80 mmHg or less DBP). The hypertension group consumed 360.5 mg calcium per day, which was lower than that of the normotension group (429.9 mg) but not showing significant difference. In the hypertension group, DBP had a significant negative correlation with plant calcium (P < 0.01) after adjusting for age, gender, body mass index (BMI), and energy intake. In the normotension group, total calcium and animal calcium intake were significantly and positively correlated with serum triglycerides. No significant relationship was found between calcium intake and blood/urine oxidative stress indices in both groups. Overall, these data suggest reconsideration of food sources for calcium consumption in management of the blood pressure or blood lipid profiles in both hypertensive and normotensive subjects.     

Postural changes in blood pressure and pulse rate among black adolescents and white adolescents: the Minneapolis Children's Blood Pressure Study

Because studies have suggested a possible relation between vascular responsiveness to postural changes and risk of subsequent myocardial infarction, the reactivity of blood pressure and pulse rate to change from supine to standing positions was examined in 158 black males, 144 black females, 342 white males, and 272 white females aged 14-16 years. The study was part of the Minneapolis Children's Blood Pressure Study and was conducted during October to December 1985. Two blood pressure readings and one pulse reading were taken after five minutes of supine rest, immediately upon standing, and five minutes after standing. After adjustment for body mass index, mean systolic blood pressure decreased, and fourth- and fifth-phase diastolic blood pressures and pulse rate increased from supine to standing positions in all race and sex groups. Black males had significantly larger changes in systolic pressure than did white males (-5.9 vs. -4.1 mmHg), and males had significantly larger changes in fourth- and fifth-phase diastolic pressures compared with females of the same race (fourth-phase diastolic pressure, 8.0 vs. 4.1 mmHg for blacks and 10.0 vs. 4.8 mmHg for whites). Fifth-phase diastolic pressure increased more than did fourth-phase diastolic pressure in all groups. No race or sex differences were seen for pulse changes. For all race-sex groups, decreases in systolic pressure were positively correlated with initial levels of supine systolic pressure, whereas increases in fourth- and fifth-phase diastolic pressures were negatively correlated with corresponding initial levels. Measurement of postural changes may provide a clinically simple and reproducible way of testing for abnormalities in blood pressure and may better discriminate those at high risk of hypertension and its cardiovascular complications than would the commonly used single-seated blood pressure measurement.     

Geographical variations in blood pressure in British men and women

Geographical variations in blood pressure have been studied using an automatic sphygmomanometer in 2596 men and women aged 25-29, 40-44 and 55-59 living in nine British towns. In males aged 40-59, systolic blood pressure showed a range in age-adjusted town means of 9.0 mmHg (p less than 0.05); in females the difference of 8.6 mmHg was not significant (p = 0.14). Mean arterial pressure (MAP) and diastolic at age 40-59 were significantly different between towns for both sexes. Differences at age 25-29 were of a similar magnitude, and the mean town blood pressures at 25-29 correlated highly with those at 40-59 [systolic; males r = 0.74 (p less than 0.05), females r = 0.65 (p = 0.059)]. The ranking of town blood pressures in an earlier study was reflected in the present study, but stronger associations were observed with cardiovascular mortality. It is concluded that geographical blood pressure variations in Britain are established by age 25-29 years.     

Blood pressure,lipids and other risk factors for cardiovascular disease in Aborigines and persons of European descent of southeastern Australia

Abstract: Based on a survey in two country towns of southeastern Australia, cardiovascular risk-factor prevalence data from Aborigines and persons of European descent are presented. The mean diastolic blood pressure in 123 Aboriginal males was 83.2 mmHg, compared with 79.2 mmHg in 272 European males (P= 0.005). In 178 Aboriginal females, mean diastolic pressure was 79.2 mmHg, compared with 76.3 mmHg in 281 European females (P = 0.006). Mean plasma total cholesterol was higher in Europeans (both males and females: 5.7 mmol/L) than in Aborigines (in males 5.2 and females 5.0 mmol/L) (male comparison, P = 0.02, female comparison, P < 0.001). The prevalence in participants aged 25 to 64 years of at least one major risk factor (diastolic blood pressure 95 mmHg or higher, plasma cholesterol 6.5 mmol/L or higher, or smoking more than one cigarette daily) was higher in both these samples of Aborigines (94 per cent in males, 89 per cent in females) and Europeans (70 per cent in males, 59 per cent in females) than in the 1989 urban sample of the National Heart Foundation (47 per cent in males, 36 per cent in females). Multivariate analyses showed statistically significant independent contributions of body mass index and the variable ‘ethnicity’ (unidentified genetic and environmental differences between the groups) to blood pressure and other risk factors. The higher cardiovascular mortality of Aborigines may be explained partly by the higher prevalence of risk factors in this group compared with other Australians. Further, the risk-factor profile may be worse among rural compared with urban Europeans.     

The differential blood pressure sign in general practice: prevalence and prognostic value

BACKGROUND: Patients sometimes have differences of > or =20/10 mmHg in their blood pressure depending on which arm is measured. The prevalence and prognostic value of this finding in general practice are unknown. If these differences are due to peripheral vascular disease, these patients may be at increased risk of cardiovascular or cerebrovascular events. OBJECTIVE: Our aim was to establish the frequency and prognostic value of a blood pressure difference between arms in one rural general practice. METHODS: Paired blood pressure readings were collected from patients attending the surgery. The outcome measures of myocardial infarction, new diagnosis of angina, a cerebrovascular event or death were recorded prospectively. RESULTS: A total of 280 patients were examined, and of these 13.6% had a systolic blood pressure difference (SBPD) of > or =20 mmHg, and 23.2% a diastolic blood pressure difference (DBPD) of > or =10 mmHg. Eighty-three patients were followed-up for 5.6 years. Patients with a DBPD of > or =10 mmHg showed a mean event-free survival of 3.3 years [95% confidence interval (CI) 2.2-4.4] compared with 5.0 years (95% CI 4.7-5.3) for those with a DBPD of <10 mmHg (P < 0.0001). Patients with an SBPD of > or =20 mmHg showed a mean event-free survival of 3.5 years (95% CI 2.3-4.7) compared with 4.9 years (95% CI 4.5-5.2) for an SBPD of <20 mmHg (P = 0.043). CONCLUSIONS: During a single assessment of blood pressure, there will be a minority of patients with a difference of > or =20/10 mmHg between their right and left arms. Measurement of both arms is therefore necessary to diagnose and treat hypertension accurately. This study suggests an association between blood pressure difference and increased morbidity and mortality. Priority should be given to managing other risk factors aggressively in those patients with a reproducible blood pressure difference of > or =20/10 mmHg.     

Projected effects of high-risk versus population-based prevention strategies in coronary heart disease

The potential benefits of a high-risk and a population strategy to prevent cardiovascular disease deaths by lowering total serum cholesterol and diastolic blood pressure were estimated. The first strategy concentrates on the top 10% of the risk distribution, and the second strategy changes risk factor distributions of the entire population. With the high-risk strategy, lowering total serum cholesterol 20% and diastolic blood pressure to 90 mmHg would result in a 28% reduction in death from cardiovascular disease. Lowering total serum cholesterol to 190 mg/dl and diastolic blood pressure to 80 mmHg with this strategy would result in a 33 per cent reduction in death from cardiovascular disease. These expected changes approximate those expected by lowering total serum cholesterol by 10% and diastolic blood pressure by 5% with the population strategy. Changes in total serum cholesterol (20% lowering) and diastolic blood pressure (10% lowering) that have been achieved in nutrition intervention trials would result in a 50% decline in cardiovascular disease death rates if applied to the whole population. If population mean total serum cholesterol could be lowered to 190 mg/dl and population mean diastolic blood pressure could be lowered to 80 mmHg, a 70% reduction in cardiovascular disease death rates would be expected. This suggests that only a population approach can prevent the majority of deaths from cardiovascular disease in a community.     

Initial therapy of essential hypertension: diuretic or beta blocker?

The ability of hydrochlorothiazide or a long-acting beta adrenergic blocker, nadolol, to reduce the blood pressure was compared in 55 patients with mild to moderately severe essential hypertension. A randomized crossover study design was employed, with 43 patients completing both legs of the study. The mean sitting diastolic blood pressures after one month of therapy were reduced by 13.6 and 14.9 mmHg with hydrochlorothiazide and nadolol, respectively. After hydrochlorothiazide therapy, the diastolic blood pressure was 90 mmHg or lower in 51 percent of the patients, and after nadolol, in 56 percent of the same patients. The results suggest that diuretics and beta adrenergic blockers are equally effective in lowering the blood pressure. Nadolol's long duration of beta adrenoreceptor blockade justifies a simplified, once daily dosage schedule.     

Risk factors for hypertensive crisis: importance of out-patient blood pressure control

OBJECTIVES: The purpose of this study was to identify independent risk factors for development of hypertensive crisis. METHODS: This was a retrospective, case-controlled study. Cases were 143 patients who presented during a 3-year period to the Emergency Department with the diagnosis of hypertensive crisis, defined as systolic pressure >/=180 mmHg and/or diastolic pressure >/=110 mmHg and symptoms of hypertensive emergency during the Emergency Department presentation. Controls were 485 patients with hypertension, matched to cases on the basis of age, sex and race, who were not admitted to the Emergency Department with an episode of hypertensive crisis during the study period. Co-morbid conditions were identified from computerized health system databases and medical records. Out-patient blood pressures were obtained from medical records from randomly selected out-patient clinic visits. RESULTS: The average blood pressure during Emergency Department presentation in patients with hypertensive crisis was 197 +/- 21/108 +/- 14 mmHg. Less successful out-patient systolic blood pressure control was an independent risk factor for hypertensive crisis [odds ratio (OR) 1.30 (1.18-1.42), per 10 mmHg, P < 0.001]. Higher out-patient diastolic blood pressures [OR 1.21 (0.99-1.43 per 10 mmHg, P = 0.07] and history of heart failure [OR 3.48 (0.94-12.94), P = 0.06] trended towards independence as risk factors. CONCLUSION: Less effective blood pressure control, based on out-patient systolic blood pressure measurements, is an independent risk factor for an Emergency Department presentation due to hypertensive crisis.     

CBO guideline 'High blood pressure' (revision)]

The revised CBO guideline 'High blood pressure' details the present scientific knowledge about the detection, diagnosis and treatment of elevated blood pressure as well as the implementation of this knowledge in practice. For both systolic and diastolic increased blood pressure the risk of cardiovascular disease and mortality gradually increases. The blood pressure is considered to be elevated if the systolic pressure is > or = 140 mmHg and/or the diastolic pressure is > 90 mmHg. For individuals aged 60 years and over, without diabetes, familiar hypercholesterolaemia or overt cardiovascular disease, 160 mmHg is the cut-off value for elevated systolic pressure. Depending on age or blood pressure level, the diagnosis 'elevated blood pressure' is established after 3 or 5 measurements over a period of some weeks (3 measurements) to 6 months (5 measurements). Where elevated blood pressure is diagnosed, lifestyle recommendations should be considered first and only if these provide insufficient results should medicinal treatments be adopted. The indication area for treatment is laid down in the case of elevated blood pressure and an absolute cardiovascular risk of 20% per 10 years. When the absolute cardiovascular risk is between 10% and 20% per year, treatment may be considered. For treatment the target value is the same as the criterion for elevated blood pressure.     

Alcohol-induced macrocytosis and blood pressure.

The effect of alcohol on blood pressure was studied prospectively in consecutive general practice patients with macrocytosis (MCV greater than or equal to 100 fl). The patients were separated into misuser and non-misuser groups on the basis of the Malm? modified Michigan Alcoholism Screening Test. There was no significant difference in the prevalence of antihypertensive medication between the misuser and non-misuser groups. When patients using antihypertensive medication were excluded and the groups were age-adjusted, male misusers (n = 95) compared to control patients (n = 22) had significantly higher diastolic (88 mmHg and 81 mmHg, respectively, P = 0.001) and systolic (146 mmHg and 137 mmHg, respectively, P less than 0.001) blood pressure values. Female misusers (n = 24), as compared to female non-misusers (n = 59) had significantly higher diastolic (83 mmHg and 82 mmHg, respectively, P = 0.04) but not systolic blood pressure values. Thus, alcohol seems to have a pressor effect predominantly among men. As 72% of men with macrocytosis were alcohol misusers and 41% of them either had elevated systolic or diastolic blood pressure, all patients with macrocytosis should be asked about their alcohol consumption and at least the males should have blood pressure measured.     

Body mass index and cardiovascular risk factors in a rural Chinese population

The metabolic consequences of obesity are well-documented in Western populations. However, limited data are available on the association between body mass index (BMI) and cardiovascular risk factors in developing countries. The authors therefore examined the association between BMI and cardiovascular risk factors in a very lean population in China. A total of 2,542 subjects aged 20-70 years from a rural area of Anqing, China, participated in a cross-sectional survey, and 1,610 provided blood samples in 1993. Mean BMI (kg/m2) was 20.7 for men and 20.9 for women. After adjustment for age, sex, education level, occupation, current alcohol use, and cigarette smoking, BMI was significantly associated with systolic and diastolic blood pressures (p < 0.0001). The adjusted odds ratio for hypertension (systolic pressure > or =140 mmHg or diastolic pressure > or = 90 mmHg) across quintiles of BMI (quintile medians: 18.0, 19.4, 20.6, 21.8, and 24.0) were 1.0, 1.34, 2.46, 2.61, and 4.90 (95% confidence interval: 3.20, 7.50). A higher BMI was directly associated with higher levels of serum total cholesterol, triglycerides, and fasting glucose and lower levels of high density lipoprotein cholesterol. These data from a very lean Chinese population confirm independent relations between body mass and cardiovascular risk factors observed in predominantly overweight Western populations and extend the range of associations to lower BMI levels than do previous studies.     

Case in Point

Abstract

Epidemiologic and clinical trial data suggest that blood pressure in patients with hypertension who are at high risk for cardiovascular events because of coronary artery disease, diabetes, chronic kidney disease, stroke, or heart failure should be reduced to < 140/90 mm Hg in patients aged < 80 years, and that systolic blood pressure should be reduced to 140 to 145 mm Hg, if tolerated, in patients aged ≥ 80 years. Studies on patients with coronary artery disease, diabetes, chronic kidney disease, stroke, and heart failure are discussed, supporting a blood pressure goal of < 140/90 mm Hg in patients aged < 80 years who are at high risk for cardiovascular events.     

Dietary calcium supplementation as a treatment for mild hypertension

The blood pressure responses of 19 mildly hypertensive (diastolic blood pressure 90-104 mmHg) individuals to treatment with either 1200 mg of elemental calcium supplementation or placebo were assessed weekly in a 6-month randomized, double-blind, placebo-controlled crossover study. Both groups showed a decrease in blood pressure (calcium treated: 6 +/- 12 mmHg systolic, 7 +/- 7 mmHg diastolic; and placebo controlled: 9 +/- 14 mmHg systolic, 9 +/- 8 mmHg diastolic). Differences between the two groups were not significant (P greater than 0.1). There were no adverse effects to either treatment. This study does not support the hypothesis that dietary calcium supplementation is more effective than placebo in reducing blood pressure in mildly hypertensive individuals.     

Serial changes in blood pressure from adolescence into adulthood.

High blood pressure is an established risk factor for cardiovascular disease outcomes in adulthood. Furthermore, numerous longitudinal studies of blood pressure in childhood with length of follow-up from 1 to 17 years indicate that blood pressure levels track over the short term. This study addresses the question of the predictive value of childhood blood pressure readings for adult levels, using repeated blood pressure determinations from a sample of 501 participants in the Fels Longitudinal Study, an ongoing cohort study in southwestern Ohio that began in 1929. A damped autoregressive model indicated tracking correlations from 0.39 (4-year intervals) to 0.24 (20 years) for systolic pressure and 0.37 (4 years) to 0.20 (20 years) for diastolic pressure. These results indicate that tracking of blood pressure persists from age 13 years to age 40 years, which translates into moderate levels of relative risk for adult hypertension (diastolic pressure above 90 mmHg) for adolescents with high normal blood pressure. The estimated relative risks of hypertension at age 35 for white 15-year-olds with a true mean diastolic pressure of 80 mmHg were 1.9 for males and 2.6 for females, relative to 15-year-olds with a true diastolic pressure of 60 mmHg.     

Hypertension and Chronic Exposure to Noise

The effects of noise on various cardiovascular parameters are conflicting and uncertain. In the current study, the authors studied 52 workers who were employed in a bedframe factory who were chronically exposed to noise and who had poor hearing. An additional group of 65 workers who had jobs in the light-metal sector and another group of 64 office workers served as two control groups; none of the controls were exposed to noise, and none had hearing defects. Blood pressure was measured for each person in the supine and standing positions, and an electrocardiogram was also performed. Sound-level measurements were taken in the workplaces. Mean systolic and diastolic blood pressures and diastolic blood pressure distributions were significantly higher in the noise-exposed group than in both control groups. Among the three groups, there were significantly different frequencies of hypertension, drops in blood pressure, and electrocardiogram anomalies. Within the group of bedframe workers, those exposed to a personal daily level of exposure (i.e., equivalent continuous noise level for exposure to noise for each individual workers in an 8-hr shift) that exceeded 90 dBA had a higher mean diastolic blood pressure and a higher frequency of diastolic hypertension than workers exposed to a personal daily level of exposure of < 90 dBA. The findings suggested that (a) work performed by the bedframe group had some effects on the cardiovascular system, (b) noise is a cardiovascular risk factor, and (c) cardiovascular effects are relative to intensity and type of exposure. Vascular damage often accompanies auditory damage, but—depending on individual susceptibility—the cardiovascular system can respond in various ways.     

Calcium antagonists and cardiovascular risk in patients with hypertension and Type 2 diabetes mellitus: evidence from the PIUMA Study. Progetto Ipertensione Umbria Monitoraggio Ambulatoriale

We conducted a retrospective analysis of all subjects with essential hypertension and Type 2 diabetes mellitus enrolled in the PIUMA (Progetto Ipertensione Umbria Monitoraggio Ambulatoriale) registry, in order to evaluate whether the use of calcium antagonists is associated with an increase in cardiovascular risk in these subjects. One hundred and sixty-four consecutive subjects with no previous cardiovascular morbid events and coexistence of essential hypertension and Type 2 diabetes mellitus were studied before therapy and followed for up to 12 years (mean 5). There were periodical contacts with family doctors and patients in order to ascertain the occurrence of major cardiovascular events. The use of calcium antagonists that preceded the event was considered for classification. None of the patients was lost to follow-up. At entry, the patients who were subsequently given calcium antagonists (n=50) had a higher clinical (174/98 vs 161/92 mmHg, both p<0.01) and 24-hr ambulatory blood pressure (150/90 vs 141/84 mmHg, both p<0.01) than those who were not. During follow-up there were 53 major cardiovascular morbid events (6.46 per 100 person-years). The rate of total cardiovascular events [5.6 vs 6.8 events per 100 person-years, relative risk 0.88 (95% CI: 0.47-1.61)] and that of cardiac events [4.0 vs 3.3 events per 100 person-years, relative risk 1.33 (95% CI: 0.62-2.89)] did not differ between users of calcium antagonists and non-users. The use of angiotensin converting enzyme inhibitors (n=66) was unrelated to the risk of cardiovascular events (relative risk 1.24, 95% CI: 0.71-2.16). In a Cox multivariate analysis, only age (p=0.002) and 24-hr pulse pressure (p=0.04) were independent predictors of cardiovascular events. In conclusion, this cohort study does not support the hypothesis that use of calcium antagonists is associated with an excess risk of adverse cardiovascular events in uncomplicated subjects with essential hypertension and Type 2 diabetes mellitus.     

Assessing cardiovascular reactivity in working women with the social competence interview

The Social Competence Interview (SCI), an interview to induce cardiovascular reactivity through recounting a stressful life experience, was used with a sample of 120 working women employed as childcare providers. Women recounted their most stressful work factor while cardiovascular reactions were monitored at 2-minute intervals (data points included 4 baseline, 6 SCI, and 3 recovery). Increases were found when comparing mean baseline and SCI measures: systolic blood pressure (SBP) increased 10.00 mmHg; diastolic blood pressure (DBP)increased 10.63 mmHg; and heart rate increased 4.57 beats per minute. Consistent with the literature SBP and DBP were higher for some subgroups of women (those who were 50 years or older, were obese, or had 4 or more risk factors) across all data points. There were no time by individual difference interactions, indicating that the patterns of change over time were the same across groups. In a logistic regression, comparing women who reached SBP > or = 140 mmHg and/or DBP > or = 90 mmHg during the SCI versus those who did not, higher BP was associated with being older and obese, having a higher level of acceptance coping, and a lower level of suppression of competing activities coping.     

Relationship of blood pressure to cardiovascular death: the effects of pulse pressure in the elderly

PURPOSE: To investigate the relationship of systolic and diastolic blood pressure to fatal myocardial infarction, fatal stroke and other death related to cardiovascular diseases (CVD). METHODS: The study was based on a prospective longitudinal study conducted by the Veterans Administration at the Boston Outpatient Clinic. Participants are male volunteers from the greater Boston area. Main outcome measures are fatal myocardial infarction, fatal stroke and other deaths related to cardiovascular diseases. The method of pooled logistic regression was used for statistical analysis. RESULTS: For younger men (age 21-59), after adjusting for effects of other risk factors, when systolic and diastolic blood pressure were considered separately, SBP was predictive of cardiovascular death (SBP: RR = 1.23; 95% CI = (1.05, 1.45) per 10 mmHg of increase), and DBP showed a nonsignificant positive trend in relation to cardiovascular death (DBP: RR = 1.27; 95% CI = (0.95, 1.69) per 10 mmHg of increase). For older men (age 60-85), when SBP and DBP were considered separately, SBP (RR = 1.26; 95% CI = (1.02, 1.55) per 15 mmHg of increase) was directly related, but DBP (RR = 1.05; 95% CI = (0.83, 1.32) per 8 mmHg of increase) was not related to cardiovascular death. However, for the elderly group, when SBP and DBP were considered jointly in the regression model, then the regression coefficient of DBP (beta = -0.018, p = 0.30) was of approximately the same absolute magnitude as that of SBP (beta = 0.021, p = 0.02) but opposite in sign. For younger men, when SBP and DBP were considered jointly, SBP (beta = 0.021, p = 0.049) but not DBP (beta = -0.001, p = 0.953) was positively related to cardiovascular death. CONCLUSIONS: We found that, for the elderly, pulse pressure (SBP-DBP) may be a more accurate predictor of cardiovascular death than either SBP or DBP alone. The relative risk per 35 mmHg of increase of pulse pressure, which equals the approximate interval from the 10th to the 90th percentile in the elderly group, is 2.1 with 95% CI = (1.1, 3.8). In younger subjects, SBP, but not DBP, is an independent predictor of fatal CVD.     

A large scale study of angiotensin II inhibition therapy in an elderly population: the CHANCE study

This 8-week, multicenter study evaluated the efficacy and safety of candesartan cilexetil (CC, 8-16 mg) in elderly (>65 years) hypertensive patients. Patients (n=3013) received CC 8 mg during 8 weeks which eventually doubled to CC 16 mg at week 4 if blood pressure remained uncontrolled (> or = 140/90 mmHg). At week 8, 65.5% of patients were normalized (BP < 140/90 mmHg). Mean changes at week 8 were -25.8, -13.2, and -12.7 mmHg for systolic, diastolic, and pulse pressure, respectively. Age, sex, and diabetic status did not influence the antihypertensive effect of CC. 68% of the patients treated with, but uncontrolled or intolerant of, prior antihypertensive treatment were normalized by CC 8-16 mg. In summary, CC 8-16 mg once daily was effective and well tolerated in the management of arterial hypertension in elderly subjects.     

Cardiovascular risk management and its impact on hypertension control in primary care in low-resource settings: a cluster-randomized trial

Objective

To evaluate a simple cardiovascular risk management package for assessing and managing cardiovascular risk using hypertension as an entry point in primary care facilities in low-resource settings.

Methods

Two geographically distant regions in two countries (China and Nigeria) were selected and 10 pairs of primary care facilities in each region were randomly selected and matched. Regions were then randomly assigned to a control group, which received usual care, or to an intervention group, which applied the cardiovascular risk management package. Each facility enrolled 60 consecutive patients with hypertension. Intervention sites educated patients about risk factors at baseline and initiated treatment with hydrochlorothiazide at 4 months in patients at medium risk of a cardiovascular event, according to a standardized treatment algorithm. Systolic blood pressure change from baseline to 12 months was the primary outcome measure.

Findings

The study included 2397 patients with baseline hypertension: 1191 in 20 intervention facilities and 1206 in 20 control facilities. Systolic and diastolic blood pressure decreased more in intervention patients than in controls. However, at 12 months more than half of patients still had uncontrolled hypertension (systolic blood pressure > 140 mmHg and/or diastolic blood pressure > 90 mmHg). Behavioural risk factors had improved among intervention patients in Nigeria but not in China. Only about 2% of hypertensive patients required referral to the next level of care.

Conclusion

Even in low-resource settings, hypertensive patients can be effectively assessed and managed in primary care facilities.