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The study examines if the low ankle brachial index (ABI) adequately predicts the risk of cardiovascular events and mortality independently of the Framingham risk score (FRS). Findings indicate that measurement of the ABI could improve the accuracy of cardiovascular prediction separately from the FRS.

A study to differentiate the advancement of subclinical atherosclerotic disease in patients with type 2 diabetes is conducted. Results conclude that treatment of low-density lipoprotein (LDL) cholesterol and systolic blood pressure bettered alternate measures of cardiovascular disease.

A randomized controlled trial is used to evaluate the efficacy of a comprehensive pharmacy care program to improve medication adherence and its associated effects on blood pressure (BP) and low-density lipoprotein cholesterol (LDL-C). The results have shown that pharmacy care program led to increase in medication adherence, medication persistence and clinically meaningful reductions in BP, but the discontinuation of this program was associated with decreased medication adherence and persistence.

Both systolic and diastolic blood pressure are important when assessing a person's risk of death from cardiovascular disease, according to a study of 342815 men. Systolic pressure is the first number in a blood pressure reading and diastolic pressure is the second number. Pulse pressure, which is the difference between the two, is less useful in predicting cardiovascular mortality., Context The sixth Joint National Committee (JNC-VI) classification system of blood pressure emphasizes both systolic blood pressure (SBP) and diastolic blood pressure (DBP) for cardiovascular disease risk assessment. Pulse pressure may also be a valuable risk assessment tool. Objective To compare relationships of SBP, DBP, and pulse pressure, separately and jointly, with cardiovascular disease-related mortality in men. Design and Setting Data from the Multiple Risk Factor Intervention Trial (MRFIT), which screened men aged 35 to 57 years from 1973 through 1975 at 22 US centers, was used to assess cardiovascular disease-related mortality through 1996. Participants A total of 342815 men without diabetes or a history of myocardial infarction were divided into 2 groups based on their age at MRFIT screening (35- to 44-year-olds and 45- to 57-year olds). Participant blood pressure levels were classified into a JNC-VI blood pressure category based on SBP and DBP (optimal, normal but not optimal, high normal, stage 1 hypertension, stage 2-3 hypertension), and pulse pressure was calculated. Main Outcome Measure Cardiovascular disease-related mortality. Results There were 25721 cardiovascular disease-related deaths. Levels of SBP and DBP were more strongly related to cardiovascular disease than pulse pressure. Relationships of SBP, DBP, and pulse pressure to cardiovascular disease-related mortality varied within JNC-VI category. Concordant elevations of SBP and DBP were associated with a greater risk of cardiovascular disease-related mortality for both age groups of men. Among men aged 45 to 57 years, higher SBP and lower DBP (discordant elevations) also yielded a greater risk of cardiovascular disease-related mortality. Conclusion In both age groups, cardiovascular disease risk assessment was improved by considering both SBP and DBP, not just SBP, DBP, or pulse pressure separately.

An increase in pulse pressure is a risk factor for death in patients with kidney failure who receive dialysis, according to a study of 37,069 hemodialysis patients. Pulse pressure is a different way of measuring blood pressure. It involves subtracting diastolic pressure from systolic pressure to measure the actual pulse of blood flow every time the heart contracts., Context: Although increased blood pressure is associated with adverse outcomes in the general population, elevated blood pressure is associated with decreased mortality in patients with end-stage renal disease undergoing maintenance hemodialysis. Recent investigations in the general population have demonstrated the predictive utility of pulse pressure (systolic minus diastolic blood pressure), a measure reflecting the pulsatile nature of the cardiac cycle. Objectives: To estimate the relationship between pulse pressure and mortality in patients undergoing maintenance hemodialysis and to test our hypothesis that an increasing pulse pressure would be associated with increased risk of death up to 1 year despite the inverse relationship between conventional blood pressure measures and mortality in patients with end-stage renal disease. Design, Setting, and Patients: Retrospective cohort investigation of patients with end-stage renal disease undergoing maintenance hemodialysis at 782 hemodialysis facilities throughout the United States. Of 44 069 eligible patients as of January 1, 1998, 37069 with complete demographic data were included in the analyses of clinical and laboratory data collected from October 1 through December 31, 1997. Patients were followed up through December 31, 1998. Main Outcome Measures: The primary study outcome was death at 1 year. A secondary outcome was the magnitude of the pulse pressure. Results: The final patient cohort was similar to national averages with respect to age, sex, race, and diabetic status. Mean (SD) pulse pressures before dialysis were 75.0 (15.0) mm Hg and 66.9 (13.9) mm Hg after dialysis. By the end of the 1-year follow-up, 5731 patients (18.4%) died. After adjusting for level of systolic blood pressure, multivariable Cox proportional hazards modeling showed a direct and consistent relationship between increasing pulse pressure and increasing death risk. Each incremental elevation of 10 mm Hg in postdialysis pulse pressure was associated with a 12% increase in the hazard for death (hazard ratio, 1.12; 95% confidence interval, 1.06-1.18). Postdialysis systolic blood pressure was inversely related to mortality with a 13% decreased hazard for death for each incremental elevation of 10 mm Hg (hazard ratio, 0.87; 95% confidence interval, 0.84-0.90). In a multivariable linear regression model, important variables directly associated with elevated pulse pressure included age, diabet es, white race, female sex, and number of years receiving dialysis (all P Conclusions: Pulse pressure is associated with risk of death in a large, nationally representative sample of patients undergoing maintenance hemodialysis. The recognition of pulse pressure as an important correlate of mortality in patients receiving dialysis highlights the need to investigate the relationship between potential therapeutic implications of conduit vessel function and clinical outcomes in patients with end-stage renal disease.

Dietary sodium restriction may be beneficial in people with hypertension but it does not appear to benefit those with normal blood pressure. Researchers evaluated 114 clinical trials evaluating the effect of sodium restriction on blood pressure. Fifty-eight trials of hypertensive patients found that sodium restriction lowered systolic and diastolic blood pressure by a small amount. However, blood pressure in 56 trials of people with normal blood pressure was not affected by sodium restriction. Sodium restriction is probably not necessary for most people., Context.---One of the controversies in preventive medicine is whether a general reduction in sodium intake can decrease the blood pressure of a population and thereby reduce the number of strokes and myocardial infarctions. In recent years the debate has been extended by studies indicating that reduced sodium intake has adverse effects. Objective.--To estimate the effects of reduced sodium intake on systolic and diastolic blood pressure (SBP and DBP), body weight, and plasma or serum levels of renin, aldosterone, catecholamines, cholesterols, and triglyceride, and to evaluate the stability of the blood pressure effect in relation to additional trials. Data Sources.-- MEDLINE search from 1966 through December 1997 and reference lists of relevant articles. Study Selection.---Studies randomizing persons to high-sodium and lowsodium diets were included if they evaluated at least one of the effect parameters. Data Extraction.--Two authors independently recorded data. Data Synthesis.--In 58 trials of hypertensive persons, the effect of reduced sodium intake as measured by urinary sodium excretion (mean, 118 mmol/24 h) on SBP was 3.9 mm Hg (95% confidence interval [Cl], 3.0-4.8 mm Hg) (P [is less than] .001) and on DBP was 1.9 mm Hg (95% Cl, 1.3-2.5 mm Hg) (P [is less than] .001). In 56 trials of normotensive persons, the effect of reduced sodium intake (mean, 160 mmol/24 h) on SBP was 1.2 mm Hg (95% Cl, 0.6-1.8 mm Hg) (P [is less than] .001) and on DBP was 0.26 mm Hg (95% Cl, -0.3-0.9 mm Hg) (P=.12). The cumulative analysis showed that this effect size has been stable since 1985. In plasma, the renin level increased 3.6-fold (P [is less than] .001), and the aldosterone level increased 3.2-fold (P [is less than] .001); the increases were proportional to the degree of sodium reduction for both renin (r=0.66; P [is less than] .001) and aldosterone (r=0.64; P [is less than] .001). Body weight decreased significantly, and noradrenaline, cholesterol, and low-density lipoprotein cholesterol levels increased. There was no effect on adrenaline, triglyceride, and high-density lipoprotein cholesterol. Conclusion.--These results do not support a general recommendation to reduce sodium intake. Reduced sodium intake may be used as a supplementary treatment in hypertension. Further long-term studies of the effects of high reduction of sodium intake on blood pressure and metabolic variables may clarify the disagreements as to the role of reduced sodium intake, but ideally trials with hard end points such as morbidity and survival should end the controversy. JAMA. 1998;279:1383-1391

Increasing dietary potassium may lower blood pressure. Researchers used meta-analysis to review 33 clinical trials assessing the health benefits of potassium supplementation in 2,609 patients. Potassium supplementation reduced systolic blood pressure by an average of 3 millimeters of mercury and diastolic blood pressure an average of 2 millimeters of mercury. Potassium supplementation appeared to be especially beneficial in people who could not reduce their sodium intake., Objective. -- To assess the effects of supplementation with oral potassium on blood pressure in humans. Design. -- Meta-analysis of randomized controlled trials. Data Sources. -- English-language articles published before July 1995. Study Selection. -- Thirty-three randomized controlled trials (2609 participants) in which potassium supplementation was the only difference between the intervention and control conditions. Data Extraction. -- Using a standardized protocol, 2 of us independently abstracted information on sample size, duration, study design, potassium dose, participant characteristics, and treatment results. Results. -- By means of a random-effects model, findings from individual trials were pooled, after results for each trial were weighted by the inverse of its variance. An extreme effect of potassium in lowering blood pressure was noted in 1 trial. After exclusion of this trial, potassium supplementation was associated with a significant reduction in mean (95% confidence interval) systolic and diastolic blood pressure of -3.11 mm Hg (-1.91 to -4.31 mm Hg) and -- 1.97 mm Hg (-0.52 to -3.42 mm Hg), respectively. Effects of treatment appeared to be enhanced in studies in which participants were concurrently exposed to a high intake of sodium. Conclusions. -- Our results support the premise that low potassium intake may play an important role in the genesis of high blood pressure. Increased potassium intake should be considered as a recommendation for prevention and treatment of hypertension, especially in those who are unable to reduce their intake of sodium.

It may be unwise to recommend dietary sodium restriction until further research confirms that the treatment is safe and effective. Researchers used meta-analysis to evaluate 56 clinical trials of the effect of sodium reduction on blood pressure. The trials covered 1,131 people with hypertension and 2,374 people with normal blood pressure. A reduction in daily sodium intake of approximately 2,000 milligrams reduced blood pressure by 3.7/0.9 in those with hypertension and by 1/0.1 in those with normal blood pressure. Reduction in blood pressure was greatest in hypertensive patients 45 or older but was insignificant in younger patients. Reductions in blood pressure were also insignificant in the people with normal blood pressure. Many of the studies that showed greater reductions in blood pressure were flawed. There is evidence that a low-sodium diet can actually be harmful., Objective. - To ascertain whether restriction of dietary sodium lowers blood pressure in hypertensive and normotensive individuals. Data Sources. - An English-language computerized literature search, restricted to human studies with Medical Subject Heading terms, "hypertension," "blood pressure," "vascular resistance," "sodium and dietary," "diet and sodium restricted," "sodium chloride," "clinical trial," "randomized controlled trial," and "prospective studies," was conducted. Bibliographies of review articles and personal files were also searched. Trial Selection. - Trials that had randomized allocation to control and dietary sodium intervention groups, monitored by timed sodium excretion, with outcome measures of both systolic and diastolic blood pressure were selected by blinded review of the methods section. Data Extraction. - Two observers extracted data independently, using purpose-designed forms, and discrepancies were resolved by discussion. Data Synthesis. - The 56 trials that met our inclusion criteria showed significant heterogeneity. Publication bias was also evident. The mean reduction (95% confidence interval) in daily urinary sodium excretion, a proxy measure of dietary sodium intake, was 95 mmol/d (71-119 mmol/d) in 28 trials with 1131 hypertensive subjects and 125 mmol/d (95-156 mmol/d) in 28 trials with 2374 normotensive subjects. After adjustment for measurement error of urinary sodium excretion, the decrease in blood pressure for a 100-mmol/d reduction in daily sodium excretion was 3.7 mm Hg (2.35-5.05 mm Hg) for systolic (P < .001) and 0.9 mm Hg (-0.13 to 1.85 mm Hg) for diastolic (P = .09) in the hypertensive trials, and 1.0 mm Hg (0.51-1.56 mm Hg) for systolic (P < .001) and 0.1 mm Hg (-0.32 to 0.51 mm Hg) for diastolic (P = .64) in the normotensive trials. Decreases in blood pressure were larger in trials of older hypertensive individuals and small and nonsignificant in trials of normotensive individuals whose meals were prepared and who lived outside the institution setting. Conclusion. - Dietary sodium restriction for older hypertensive individuals might be considered, but the evidence in the normotensive population does not support current recommendations for universal dietary sodium restriction. (JAMA 1996;275:1590-1597)

Weight reduction, an exercise program and a low-salt diet could reduce the number of Americans who have high blood pressure by 20% to 50%. Hypertension is a major risk factor for cardiovascular diseases such as atherosclerosis, heart attack and stroke. Surveys indicate that one out of four Americans has high blood pressure. Hypertension is described as a blood pressure greater than 140/90. The Framingham Study has found that blood pressure increases with age, probably because the blood vessels become less elastic. Two-thirds of the people participating in the Framingham Study developed hypertension over the 30-year follow-up. In the past, many doctors focused on diastolic blood pressure, but in the Framingham Study, systolic blood pressure was a more important predictor of cardiovascular disease. Despite treatment successes, 2 million people develop hypertension every year. Efforts should focus on prevention, supported by studies that weight loss can lower blood pressure., Objective. - to examine the prevalence, incidence, predisposing factors for hypertension, its hazards as an ingredient of the cardiovascular risk profile, and the implications of this information for prevention and treatment. Methods. - prospective longitudinal analysis of 36-year follow-up data from the Framingham Study of the relation of antecedent blood pressure to occurrence of subsequent cardiovascular morbidity and mortality depending on the metabolically linked burden of associated risk factors. Results.- hypertension is one of the most prevalent and powerful contributors to cardiovascular diseases, the leading cause of death in the United States. There is, on average, a 20 mm Hg systolic and 10 mm Hg diastolic increment increase in blood pressure from age 30 to 65 years. Isolated systolic hypertension is the dominant variety. There is no evidence of a decline in the prevalence of hypertension over 4 decades despite improvements in its detection and treatment. Hypertension contributes to all of the major atheroscletoric cardiovascular disease outcomes increasing risk, on average, 2- to 3-fold. Coronary disease, the most lethal and common sequela, deserves highest priority. Hypertension clusters with dyslipidemia, insulin resistance, glucose intolerance, and obesity, occurring in isolation in less than 20%. The hazard depends on the number of these associated metabolically linked risk factors present. Coexistent overt cardiovascular disease also influences the hazard and choice of therapy. Conclusion. - The absence of a decline in the prevalence of hypertension indicates an urgent need for primary prevention by weight control, exercise, and reduced salt and alcohol intake. The urgency and choice of therapy of existing hypertension should be based on the multivariate cardiovascular risk profile that more appropriately targets hypertensive persons for treatment and prevention of cardiovascular sequelae.

More research is needed on the link between protein intake and blood pressure. Several observational studies have found that people with high-protein diets seemed to have lower blood pressure. Clinical trials have failed to confirm this, but many of these trials were not designed primarily to study the relationship between protein intake and blood pressure. Many nutritionists believe that high-protein diets can damage the kidney. It is also unclear how high-protein diets would reduce blood pressure. Presumably, the effect would arise from increased blood levels of amino acids, which would affect blood vessels or the region of the brain that affects blood pressure. But amino acid metabolism is tightly controlled and is not affected substantially by diet. Large, well-designed studies are needed to evaluate the link between protein intake and hypertension, which affects an estimated 50 million Americans., Objective. - To review published and presented data on the relationship between dietary protein and blood pressure in humans and animals. Data Sources. - Bibliographies from review articles and books on diet and blood pressure that had references to dietary protein. The bibliographies were supplemented with computerized MEDLINE search restricted to English language and abstracts presented at epidemiologic meetings. Study Selection. - Observational and intervention studies in humans and experimental studies in animals. Data Extraction. - In human studies, systolic or diastolic blood pressure were outcome measures, and dietary protein was measured by dietary assessment methods or by urine collections. in animal studies, blood pressure and related physiological effects were outcome measures, and experimental treatment included protein or amino acids. Data Synthesis. - Historically, dietary protein has been thought to raise blood pressure; however, studies conducted in Japan raised the possibility of an inverse relationship. Data analyses from subsequent observational studies in the United States and elsewhere have provided evidence of an inverse relationship between protein and blood pressure. However, intervention studies have mostly found no significant effects of protein on blood pressure. Few animal studies have specifically examined the effects of increased dietary protein on blood pressure. Conclusions. - Because of insufficient data and limitations in previous investigations, better controlled and adequately powered human studies are needed to assess the effect of dietary protein on blood pressure. in addition, more research using animal models, in which experimental conditions are highly controlled and detailed mechanistic studies can be performed, is needed to help provide experimental support for or against the protein-blood pressure hypothesis.

Calcium supplements could significantly reduce blood pressure and lower the risk of preeclampsia in pregnant women. Preeclampsia is characterized by high blood pressure and protein in the urine, which is a sign of kidney damage. Researchers used meta-analysis to analyze 14 controlled trials of the use of calcium supplements in 2,459 pregnant women. Pooling the results of all the trials revealed a reduction of 5.4 mm Hg in systolic pressure and 3.4 mm Hg in diastolic pressure in the women taking calcium supplements compared to those who did not take calcium. Women taking calcium had approximately one-third the risk of developing hypertension or preeclampsia. They also had approximately two-thirds the risk of premature delivery or fetal growth retardation., Objective.--To review the effect of calcium supplementation during pregnancy on blood pressure, preeclampsia, and adverse outcomes of pregnancy. Data Source.--We searched MEDLINE and EMBASE for 1966 to May 1994. We contacted authors of eligible trials to ensure accuracy and completeness of data and to identify unpublished trials. Study Selection.--Fourteen randomized trials involving 2459 women were eligible. Data Extraction.--Reviewers working independently in pairs abstracted data and assessed validity according to six quality criteria. Data Synthesis.--Each trial yielded differences in blood pressure change between calcium supplementation and control groups that we weighted by the inverse of the variance. The pooled analysis showed a reduction in systolic blood pressure of -5.40 mm Hg (95% confidence interval [Cl], -7.81 to -3.00 mm Hg; P

Calcium supplements may lower blood pressure slightly in people with hypertension but it does not appear to have a significant effect in people with normal blood pressure. Researchers used meta-analysis to review 33 controlled clinical trials that studied the effect of calcium supplements on blood pressure. Overall, the studies included 1,214 people who took calcium supplements and 1,198 who did not. A pooled analysis of all the studies showed that calcium supplementation reduced systolic blood pressure by 1.27 mm Hg and diastolic blood pressure by .24 mm Hg. In the six studies that specifically labelled one group as hypertensive and the other as normotensive, calcium supplements reduced systolic blood pressure in the hypertensive participants by 4.3 mm Hg and diastolic pressure by 1.5 mm Hg. In the normotensive participants, systolic pressure dropped .27 mm Hg and diastolic pressure dropped .33 mm Hg.

Young children who take in large amounts of calcium in their diet may have lower systolic blood pressure than those who do not. Blood pressure measurements have two components: systolic blood pressure (the top number) and diastolic blood pressure (the bottom number). The diets of 89 children between three and six years old were followed for an average of 9.6 days. Analysis of dietary calcium and systolic blood pressure found that for each unit of dietary calcium consumed per day, systolic blood pressure decreased a unit. The average systolic blood pressure of children with the highest dietary intake of calcium was six points higher than that of children who had the lowest dietary intake of calcium. No association was found between dietary calcium levels and diastolic blood pressure. Children who consumed large amounts of dietary calcium also ate large amounts of fat, however, since dairy products were the main source of dietary calcium. Parents of children over age two or three should feed them low-fat dairy products to reduce their risk of atherosclerosis later in life.

The outcomes of the Stop Atherosclerosis in Native Diabetics Study (SANDS) are highlighted. It is suggested that SANDS is suitable to determine whether aggressive pharmacological treatment or lower level treatment should be undertaken to reduce cardiovascular diseases.