Control of blood pressure and risk of first acute myocardial infarction: Skaraborg hypertension project.

OBJECTIVE--To analyse the relation between treated blood pressure and concomitant risk factor and morbidity from acute myocardial infarction. DESIGN--Prospective longitudinal study. Treated blood pressures and other variables were used to predict acute myocardial infarction. SETTING--Primary health care in Skaraborg, Sweden. SUBJECTS--1121 men and 1453 women aged 40-69 years at registration at outpatient clinics, 1977-81, with no evidence of previous myocardial infarction were followed up for an average of 7.4 years. Subjects were undergoing treatment with drugs to lower blood pressure or had blood pressure that exceeded the systolic or diastolic limits, or both, for diagnosis (> 170/> 105 mm Hg (patients aged 40-60 years) and > 180/> 110 mm Hg (older than 60 years)) on three different occasions, or both. MAIN OUTCOME MEASURES--First validated event of fatal or non-fatal acute myocardial infarction. RESULTS--In men but not in women there was a negative relation between treated diastolic blood pressure and risk of acute myocardial infarction. Left ventricular hypertrophy and smoking were contributory risk factors in both sexes, as was serum cholesterol concentration in men. In men with normal electrocardiograms (n = 345) risk increased with increasing diastolic blood pressure (P = 0.047), whereas the opposite was found in men with electrocardiograms suggesting ischaemia or hypertrophy, or both (n = 499, P = 0.009). In those with a reading of 95-99 mm Hg the relative risk was 0.30 (P = 0.034); at > or = 100 mm Hg it was 0.37 (P = 0.027). No similar relations were seen in women or for systolic blood pressure. CONCLUSION--It may be hazardous to lower diastolic blood pressure below 95 mm Hg in hypertensive men with possible ischaemia or hypertrophy, or both. Electrocardiographic findings should be considered when treatment goals are decided for men with hypertension.     

Case-control study of stroke and the quality of hypertension control in north west England.

OBJECTIVE: To examine the risk of stroke in relation to quality of hypertension control in routine general practice across an entire health district. DESIGN: Population based matched case-control study. SETTING: East Lancashire Health District with a participating population of 388,821 aged < or = 80. SUBJECTS: Cases were patients under 80 with their first stroke identified from a population based stroke register between 1 July 1994 and 30 June 1995. For each case two controls matched with the case for age and sex were selected from the same practice register. Hypertension was defined as systolic blood pressure > or = 160 mm Hg or diastolic blood pressure > or = 95 mm Hg, or both, on at least two occasions within any three month period or any history of treatment with antihypertensive drugs. MAIN OUTCOME MEASURES: Prevalence of hypertension and quality of control of hypertension assessed by using the mean blood pressure recorded before stroke) and odds ratios of stroke (derived from conditional logistic regression). RESULTS: Records of 267 cases and 534 controls were examined; 61% and 42% of these subjects respectively were hypertensive. Compared with non-hypertensive subjects hypertensive patients receiving treatment whose average pre-event systolic blood pressure was controlled to < 140 mm Hg had an adjusted odds ratio for stroke of 1.3 (95% confidence interval 0.6 to 2.7). Those fairly well controlled (140-149 mm Hg), moderately controlled (150-159 mm Hg), or poorly controlled (> or = 160 mm Hg) or untreated had progressively raised odds ratios of 1.6, 2.2, 3.2, and 3.5 respectively. Results for diastolic pressure were similar; both were independent of initial pressures before treatment. Around 21% of strokes were thus attributable to inadequate control with treatment, or 46 first events yearly per 100,000 population aged 40-79. CONCLUSIONS: Risk of stroke was clearly related to quality of control of blood pressure with treatment. In routine practice consistent control of blood pressure to below 150/90 mm Hg seems to be required for optimal stroke prevention.     

Effectiveness of programme for reducing cardiovascular risk for men in one general practice.

OBJECTIVES--To assess the effectiveness of a programme for reducing cardiovascular risk in men in terms of clinical measurements and perceptions of patients. DESIGN--Collection of paired data on men attending well person clinics over three to five years. Questionnaire to determine changes in risk related habits. SETTING--Well person clinics in rural general practice with five partners in mid-Wales. SUBJECTS--The first 687 men seen in the clinic: analysable data obtained on 520. Initial age range 28-60 years. MAIN OUTCOME MEASURES--Analysis of serum cholesterol concentration (mmol/l) and blood pressure (mm Hg). Changes in diet, exercise, smoking, and drinking. RESULTS--Mean (SD) cholesterol concentration for all subjects increased from 5.8 (1.0) to 6.0 (1.0), p < 0.001. Overall percentage of ideal weight and mean systolic blood pressure also increased. Mean diastolic blood pressure was unchanged at 84 mm Hg. Professed dietary change, age, and number of visits all had significant effects on final cholesterol concentration. Those seen more often showed a significant decrease in cholesterol concentrations (in those seen more than twice mean (SD) initial value 6.7 (0.9) mmol/l v final value 6.5 (1.0) mmol/l, p < 0.001). Those over 45 years at start of study showed a significant decrease in diastolic blood pressure (mean (SD) initial value 89 (9) mm Hg v final value 86 (7) mm Hg, p < 0.001). CONCLUSIONS--These clinics are not effective in achieving a reduction in mean cholesterol concentration or blood pressure, despite evidence that the message of reduction in risk had been successfully transmitted. Success was achieved in older patients and those in whom a definite problem was identified. Identification of high risk groups and clinical case finding with appropriate long term follow up may be more cost effective in reducing cardiovascular risk than non-specific screening of the whole population.     

Waist circumference action levels in the identification of cardiovascular risk factors: prevalence study in a random sample.

OBJECTIVE--To determine the frequency of cardiovascular risk factors in people categorised by previously defined "action levels" of waist circumference. DESIGN--Prevalence study in a random population sample. SETTING--Netherlands. SUBJECTS--2183 men and 2698 women aged 20-59 years selected at random from the civil registry of Amsterdam and Maastricht. MAIN OUTCOME MEASURES--Waist circumference, waist to hip ratio, body mass index (weight (kg)/height (m2)), total plasma cholesterol concentration, high density lipoprotein cholesterol concentration, blood pressure, age, and lifestyle. RESULTS--A waist circumference exceeding 94 cm in men and 80 cm in women correctly identified subjects with body mass index of > or = 25 and waist to hip ratios > or = 0.95 in men and > or = 0.80 in women with a sensitivity and specificity of > or = 96%. Men and women with at least one cardiovascular risk factor (total cholesterol > or = 6.5 mmol/l, high density lipoprotein cholesterol < or = 0.9 mmol/l, systolic blood pressure > or = 160 mm Hg, diastolic blood pressure > or = 95 mm Hg) were identified with sensitivities of 57% and 67% and specificities of 72% and 62% respectively. Compared with those with waist measurements below action levels, age and lifestyle adjusted odds ratios for having at least one risk factor were 2.2 (95% confidence interval 1.8 to 2.8) in men with a waist measurement of 94-102 cm and 1.6 (1.3 to 2.1) in women with a waist measurement of 80-88 cm. In men and women with larger waist measurements these age and lifestyle adjusted odds ratios were 4.6 (3.5 to 6.0) and 2.6 (2.0 to 3.2) respectively. CONCLUSIONS--Larger waist circumference identifies people at increased cardiovascular risks.     

Low blood pressure and depression in older men: a population based study.

OBJECTIVE--To determine if an association exists between low blood pressure and depressive symptoms in older men living in the community. DESIGN--Cross sectional, population based study. SETTING--Town of Rancho Bernardo, California, United States. SUBJECTS--846 men aged 60-89 years. Comparisons between hypotensive, normotensive, and hypertensive groups were limited to 594 men not taking drugs for hypertension. MAIN OUTCOME MEASURES--Mean scores on Beck depression inventory and prevalence of scores > or = 13. RESULTS--Men with diastolic blood pressure < 75 mm Hg had significantly higher depression scores (mean scores 6.35 v 4.96; P < 0.001) and more categorical depression (7.6% v 1.8% with scores > or = 13; P < 0.01) than men with diastolic blood pressure levels between 75 and 85 mm Hg. Men with diastolic blood pressure levels > 85 mm Hg had higher depression scores than men with intermediate blood pressure levels (mean scores 5.85 v 4.96; P < 0.05). Men with diastolic hypotension scored significantly higher on both affective and somatic item subscales of the Beck depression inventory and on individual measures of fatigue, pessimism, sadness, loss of appetite, weight loss, and preoccupation with health. Low diastolic blood pressure was a significant predictor of both mean depression score and prevalence of categorical depression, independent of age and change in weight since the baseline visit. The presence of several chronic diseases was associated with depressed mood and higher blood pressure but not with low blood pressure. CONCLUSION--The association of relatively low diastolic blood pressure with higher depressive symptom scores and rates of categorical depression was independent of age or weight loss. Since fatigue is a prominent symptom of depression, any association of low blood pressure with fatigue could reflect depressive disorders or clinically important depression.     

Tight blood pressure control and risk of macrovascular and microvascular complications in type 2 diabetes: UKPDS 38

Objective: To determine whether tight control of blood pressure prevents macrovascular and microvascular complications in patients with type 2 diabetes.Design: Randomised controlled trial comparing tight control of blood pressure aiming at a blood pressure of <150/85 mm Hg (with the use of an angiotensin converting enzyme inhibitor captopril or a β blocker atenolol as main treatment) with less tight control aiming at a blood pressure of <180/105 mm Hg.Setting: 20 hospital based clinics in England, Scotland, and Northern Ireland.Subjects: 1148 hypertensive patients with type 2 diabetes (mean age 56, mean blood pressure at entry 160/94 mm Hg); 758 patients were allocated to tight control of blood pressure and 390 patients to less tight control with a median follow up of 8.4 years.Main outcome measures: Predefined clinical end points, fatal and non-fatal, related to diabetes, deaths related to diabetes, and all cause mortality. Surrogate measures of microvascular disease included urinary albumin excretion and retinal photography.Results: Mean blood pressure during follow up was significantly reduced in the group assigned tight blood pressure control (144/82 mm Hg) compared with the group assigned to less tight control (154/87 mm Hg) (P<0.0001). Reductions in risk in the group assigned to tight control compared with that assigned to less tight control were 24% in diabetes related end points (95% confidence interval 8% to 38%) (P=0.0046), 32% in deaths related to diabetes (6% to 51%) (P=0.019), 44% in strokes (11% to 65%) (P=0.013), and 37% in microvascular end points (11% to 56%) (P=0.0092), predominantly owing to a reduced risk of retinal photocoagulation. There was a non-significant reduction in all cause mortality. After nine years of follow up the group assigned to tight blood pressure control also had a 34% reduction in risk in the proportion of patients with deterioration of retinopathy by two steps (99% confidence interval 11% to 50%) (P=0.0004) and a 47% reduced risk (7% to 70%) (P=0.004) of deterioration in visual acuity by three lines of the early treatment of diabetic retinopathy study (ETDRS) chart. After nine years of follow up 29% of patients in the group assigned to tight control required three or more treatments to lower blood pressure to achieve target blood pressures.Conclusion: Tight blood pressure control in patients with hypertension and type 2 diabetes achieves a clinically important reduction in the risk of deaths related to diabetes, complications related to diabetes, progression of diabetic retinopathy, and deterioration in visual acuity.

Key messages

• This study showed that tight control of blood pressure based on captopril or atenolol as first agents and aiming for both a systolic blood pressure <150 mm Hg and diastolic pressure <85 mm Hg achieved a mean 144/82 mm Hg compared with 154/87 mm Hg in a control group
• 29% of patients in the tight control group required three or more hypotensive treatments
• Tight control of blood pressure reduced the risk of any non-fatal or fatal diabetic complications and of death related to diabetes; deterioration in visual acuity was also reduced
• Reducing blood pressure needs to have high priority in caring for patients with type 2 diabetes

     

Relation between birth weight at term and systolic blood pressure in adolescence.

OBJECTIVE--To examine whether birth weight is related to systolic blood pressure during adolescence. DESIGN--Retrospective (comparative) cohort study. The observers who traced and studied the subjects were unaware of their case-control status. SUBJECTS--330 subjects were born in Cardiff in 1975-7. Cases who were low birth weight at term (< 2500 g) were matched with controls of normal birth weight (3000-3800 g) at term. MAIN OUTCOME MEASURES--Systolic blood pressure measured by random zero sphygmomanometry in the subject''s right arm with the subject supine, corrected for size and age. RESULTS--The mean age at examination was 15.7 years. The mean systolic blood pressure of the cases was 105.8 mm Hg and of the controls 107.5 mm Hg. The corrected difference (95% confidence interval) in systolic blood pressure between the cases and controls was 1 mm Hg (-3 to +1 mm Hg; two tailed probability 0.33). CONCLUSION--Systolic blood pressure in adolescents of low birth weight is not significantly different from that of adolescents of normal birth weights.     

Fate in intermittent claudication: outcome and risk factors.

The fate of 257 consecutive patients (100 women) aged 36-85 years (mean 65) first seen with intermittent claudication in 1977 was analysed after a mean of 6.5 (SD 0.5) years. When first seen none of the patients complained of rest pain or had ulcers or gangrenous lesions on the feet. At follow up 113 of the patients (44%) had died. Causes of death were no different from those in the general population. Mortality was twice that of the general population matched for age and sex. Mortality among the men was twice that among the women. In men under 60 mortality was four times that expected. The rate of clinical progression of the arteriosclerotic disease (that is, rest pain or gangrene) of the worst affected leg was 7.5% in the first year after referral. Thereafter the rate was 2.2% a year. An ankle systolic blood pressure below 70 mm Hg, a toe systolic blood pressure below 40 mm Hg, or an ankle/arm pressure index below 50% were individually significantly associated with progression of the arteriosclerotic disease. These findings show the importance of peripheral blood pressure measurements in the management of patients with intermittent claudication due to arteriosclerotic disease.     

Use of ankle brachial pressure index to predict cardiovascular events and death: a cohort study.

OBJECTIVE: To determine whether a low ankle brachial pressure index is associated with an increased risk of cardiovascular events and death, and whether the prediction of such events could be improved by including this index. DESIGN: Cohort study. SETTING: 11 practices in Edinburgh, Scotland. SUBJECTS: 1592 men and women aged 55-74 years selected at random from the age-sex registers of 11 general practices and followed up for 5 years. MAIN OUTCOME MEASURES: Incidence of fatal and non-fatal cardiovascular events and all cause mortality. RESULTS: At baseline 90 (5.7%) of subjects had an ankle brachial pressure index < or = 0.7, 288 (18.2%) had an index < or = 0.9, and 566 (35.6%) < or = 1.0. After five years subjects with an index < or = 0.9 at baseline had an increased risk of non-fatal myocardial infarction (relative risk 1.38, 95% confidence interval 0.88 to 2.16), stroke (1.98, 1.05 to 3.77), cardiovascular death (1.85, 1.15 to 2.97), and all cause mortality (1.58, 1.14 to 2.18) after adjustment for age, sex, coronary disease, and diabetes at baseline. The ability to predict subsequent events was greatly increased by combining the index with other risk factors--for example, hypertensive smokers with normal cholesterol concentrations had a positive predictive value of 25.0%, increasing to 43.8% in subjects with a low index and decreasing to 15.6% in those with a normal index. CONCLUSION: The ankle brachial pressure index is a good predictor of subsequent cardiovascular events, and improves on predictions by conventional risk factors alone. It is simple and accurate and could be included in routine screening of cardiovascular status.     

Determination of who may derive most benefit from aspirin in primary prevention: subgroup results from a randomised controlled trial

ObjectiveTo determine which groups of patients may derive particular benefit or experience harm from the use of low dose aspirin for the primary prevention of coronary heart disease.DesignRandomised controlled trial.Setting108 group practices in the Medical Research Council''s general practice research framework who were taking part in the thrombosis prevention trial.Participants5499 men aged between 45 and 69 years at entry who were at increased risk of coronary heart disease.ResultsAspirin reduced coronary events by 20%. This benefit, mainly for non-fatal events, was significantly greater the lower the systolic blood pressure at entry (interaction P=0.0015), the relative risk at pressures 130 mm Hg being 0.55 compared with 0.94 at pressures >145 mm Hg. Aspirin also reduced strokes at low but not high pressures, the relative risks being 0.41 and 1.42 (P=0.006) respectively. The relative risk of all major cardiovascular events—that is, the sum of coronary heart disease and stroke—was 0.59 at pressures <130 mm Hg compared with 1.08 at pressures >145 mm Hg (P=0.0001).ConclusionEven with the limitations of subgroup analyses the evidence suggests that the benefit of low dose aspirin in primary prevention may occur mainly in those with lower systolic blood pressures, although it is not clear even in these men that the benefit outweighs the potential hazards. Men with higher pressures may be exposed to the risks of bleeding while deriving no benefit through reductions in coronary heart disease and stroke.     

Effectiveness of health checks conducted by nurses in primary care: final results of the OXCHECK study. Imperial Cancer Research Fund OXCHECK Study Group.

OBJECTIVE--To determine the effectiveness of health checks, performed by nurses in primary care, in reducing risk factors for cardiovascular disease and cancer. DESIGN--Randomised controlled trial. SETTING--Five urban general practices in Bedfordshire. SUBJECTS--2205 men and women who were randomly allocated a first health check in 1989-90 and a re-examination in 1992-3 (the intervention group); 1916 men and women who were randomly allocated an initial health check in 1992-3 (the control group). All subjects were aged 35-64 at recruitment in 1989. MAIN OUTCOME MEASURES--Serum total cholesterol concentration, blood pressure, body mass index, and smoking prevalence (with biochemical validation of cessation); self reported dietary, exercise, and alcohol habits. RESULTS--Mean serum total cholesterol was 3.1% lower in the intervention group than controls (difference 0.19 mmol/l (95% confidence interval 0.12 to 0.26)); in women it was 4.5% lower (P < 0.0001) and in men 1.6% (P < 0.05), a significant difference between the sexes (P < 0.01). Self reported saturated fat intake was also significantly lower in the intervention group. Systolic and diastolic blood pressures and body mass index were respectively 1.9%, 1.9%, and 1.4% lower in the intervention group (P < 0.005 in all cases). There was a 3.9% (2.4 to 5.3) difference in the percentage of subjects with a cholesterol concentration > or = 8 mmol/l, but no significant differences in the number with diastolic blood pressure > or = 100 mm Hg or body mass index > or = 30 kg/m2. There was no significant difference between the two groups in prevalence of smoking or excessive alcohol use. Annual rechecks were no more effective than a single recheck at three years, but health checks led to a significant increase in visits to the nurse according to patients'' degree of cardiovascular risk. CONCLUSIONS--The benefits of health checks were sustained over three years. The main effects were to promote dietary change and reduce cholesterol concentrations; small differences in blood pressure may have been attributable to accommodation to measurement. The benefits of systematic health promotion in primary care are real, but must be weighed against the costs in relation to other priorities.     

Is exercise good for high blood pressure?

Ten men with uncomplicated essential hypertension (mean standing blood pressure 165/109 mm Hg) and 10 normal controls matched for age and weight were studied for the hypotensive potential of moderate exercise. Tests were conducted on a treadmill set to induce a steady heart rate of 120 beats/min and performed over five 10-minute periods separated by three minutes'' rest and finishing with 30 minutes'' sitting quietly in a chair.During exercise the mean systolic pressures were identical in the hypertensive patients and controls (175±SEM 5 mm Hg), the controls therefore sustaining an appreciably greater increase in pressure. During the 30-minute rest period after the tests both the control and hypertensive groups showed a significant and sustained fall in absolute systolic pressures as compared with pre-exercise values (p <0·001), the mean percentage reductions being 22% and 25% respectively.If a fall in blood pressure after exercise is maintained for four to 10 hours, then a “good walk” twice a day might be reasonable treatment for mild hypertension. Studies are continuing to determine the amount of exercise needed and the duration for which the reduction in blood pressure is maintained.     

Non-fasting serum triglyceride concentration and mortality from coronary heart disease and any cause in middle aged Norwegian women.

OBJECTIVE--To study the association between non-fasting serum triglyceride concentrations and mortality in women from coronary and cardiovascular disease and all causes. DESIGN--Follow up by ambulatory teams of men and women who underwent cardiovascular screening for a mean of 14.6 years. SETTING--National health screening service in Norway. SUBJECTS--25,058 men and 24,535 women aged 35-49 years. MAIN OUTCOME MEASURE--Predictive value of non-fasting serum triglyceride concentrations. RESULTS--At initial screening total serum cholesterol concentration, serum triglyceride concentration, blood pressure, height, and weight were measured, and self reported information about smoking habits, physical activity, and time since last meal were recorded. During subsequent follow up 108 women died from coronary heart disease, 238 from cardiovascular diseases, and 931 from all causes. In women mortality increased steadily with increasing triglyceride concentration for all three causes of death. With the proportional hazards model and adjustment for age, systolic blood pressure, total cholesterol concentration, time since last meal, and number of cigarettes a day the relative risk between triglyceride concentration > or = 3.5 mmol/l and < 1.5 mmol/l was 4.7 (95% confidence interval 2.5 to 8.9) for deaths from coronary heart disease, 3.0 (1.9 to 4.8) for deaths from cardiovascular disease, 2.3 (1.8 to 2.9) for total deaths in all women. CONCLUSIONS--A raised non-fasting concentration of triglycerides is an independent risk factor for mortality from coronary heart disease, cardiovascular disease, and any cause mortality among middle aged Norwegian women in contrast to what is seen in men.     

Bezafibrate in men with lower extremity arterial disease: randomised controlled trial

ObjectiveTo assess the effect of bezafibrate on the risk of coronary heart disease and stroke in men with lower extremity arterial disease.DesignDouble blind placebo controlled randomised trial.Setting85 general practices and nine hospital vascular clinics.Participants1568 men, mean age 68.2 years (range 35 to 92) at recruitment.InterventionsBezafibrate 400 mg daily (783 men) or placebo (785 men).ResultsBezafibrate did not reduce the incidence of coronary heart disease and stroke. There were 150 and 160 events in the active and placebo groups respectively (relative risk 0.96, 95% confidence interval 0.76 to 1.21). There were 90 and 111 major coronary events in the active and placebo groups respectively (0.81, 0.60 to 1.08), of which 64 and 65 were fatal (0.95, 0.66 to 1.37) and 26 and 46 non-fatal (0.60, 0.36 to 0.99). Beneficial effects on non-fatal events were greatest in men aged <65 years at entry, in whom benefit was also seen for all coronary events (0.38, 0.20 to 0.72). There were no significant effects in older men. There were 60 strokes in those on active treatment and 49 in those on placebo (1.34, 0.80 to 2.01). There were 204 and 195 deaths from all causes in the two groups respectively (1.03, 0.83 to 1.26). Bezafibrate reduced the severity of intermittent claudication for up to three years.ConclusionsBezafibrate has no effect on the incidence of coronary heart disease and of stroke combined but may reduce the incidence of non-fatal coronary events, particularly in those aged <65 years at entry, in whom all coronary events may also be reduced.

What is already known on this topic

The beneficial effects of bezafibrate on blood lipids and fibrinogen concentrations should reduce the incidence of heart attacks and strokesSo far, however, there is only limited evidence on clinical outcomes from randomised controlled trials

What this study adds

Treatment with bezafibrate was not associated with a reduction in the combined incidence of heart attacks and strokes, though there were substantially fewer non-fatal heart attacks in those taking bezafibrateBezafibrate was associated with a reduction in the incidence of all heart attacks, especially non-fatal, in men aged <65 yearsBezafibrate seems to reduce the severity of intermittent claudication for two or three years     

Blood pressure in prospective population based cohort of newborn and infant twins.

OBJECTIVE--To describe blood pressure in twins during infancy. DESIGN--Prospective study of cohort of twins. SETTING--Teaching hospital in Florida. SUBJECTS--166 viable twin pairs born between July 1976 and December 1989. MAIN OUTCOME MEASURES--Blood pressure and body weight at birth, at 14 days, and at 1, 3, 6, 9, and 12 months. RESULTS--Both systolic and diastolic pressure correlated with body weight throughout infancy (at birth r = 0.41, P < 0.001 and r = 0.42, P < 0.001 respectively; at 1 year r = 0.23, P < 0.001 and r = 0.26, P < 0.001 respectively). In infants weighing < 1500 g at birth mean blood pressure rose from about 45/25 mm Hg to 101/55 mm Hg from birth to the age of 1 year, while in infants weighing > 3000 g at birth it rose from 63/39 mm Hg to 100/61 mm Hg; corresponding mean body weights at 1 year were 7.86 kg and 9.88 kg. Differences in birth weight within pairs of monozygotic twins were negatively correlated with such differences in systolic blood pressure at 1 year (r = -0.37, P < 0.01). CONCLUSIONS--Blood pressure and body weights in twins showed strongly positive but generally declining correlations throughout infancy. Twins of lower birth weight showed a more rapid rate of rise in blood pressure during infancy. At 1 year the catch up in blood pressure exceeded that in body weight. Greater differences in birth weights between monozygotic twins were associated with smaller differences in systolic blood pressure at 1 year, suggesting that intrauterine environmental factors related to birth weight are important in determining blood pressure in infancy.     

Intersalt revisited: further analyses of 24 hour sodium excretion and blood pressure within and across populations. Intersalt Cooperative Research Group.

OBJECTIVES--To assess further the relation in Intersalt of 24 hour urinary sodium to blood pressure of individuals and populations, and the difference in blood pressure from young adulthood into middle age. DESIGN--Standardised cross sectional study within and across populations. SETTING--52 population samples in 32 countries. SUBJECTS--10,074 men and women aged 20-59. MAIN OUTCOME MEASURES--Association of sodium and blood pressure from within population and cross population multiple linear regression analyses with multivariate correction for regression dilution bias. Relation of sample median daily urinary sodium excretion to difference in blood pressure with age. RESULTS--In within population analyses (n = 10,074), individual 24 hour urinary sodium excretion higher by 100 mmol (for example, 170 v 70 mmol) was associated with systolic/diastolic blood pressure higher on average by 3/0 to 6/3 mm Hg (with and without body mass in analyses). Associations were larger at ages 40-59. In cross population analyses (n = 52), sample median 24 hour sodium excretion higher by 100 mmol was associated with median systolic/diastolic pressure higher on average by 5-7/2-4 mm Hg, and estimated mean difference in systolic/diastolic pressure at age 55 compared with age 25 greater by 10-11/6 mm Hg. CONCLUSIONS--The strong, positive association of urinary sodium with systolic pressure of individuals concurs with Intersalt cross population findings and results of other studies. Higher urinary sodium is also associated with substantially greater differences in blood pressure in middle age compared with young adulthood. These results support recommendations for reduction of high salt intake in populations for prevention and control of adverse blood pressure levels.     

Long-term risk of a major cardiovascular event by apoB,apoA-1, and the apoB/apoA-1 ratio—Experience from the Swedish AMORIS cohort: A cohort study

BackgroundElevated apolipoprotein B (apoB) and elevated apoB/apoA-1 ratio increase the risk of myocardial infarction (MI) and stroke, whereas high apoA-1 is protective. We study how these apolipoproteins are associated with major adverse cardiovascular events (MACEs), whether apoA-1 contributes to this association, and whether abnormal values occur decades before such events develop.Methods and findingsIn the Swedish AMORIS (Apolipoprotein-related MOrtality RISk) cohort study, 137,100 men and women aged 25–84 years were followed an average 17.8 years. ApoB, apoA-1, and the apoB/apoA-1 ratio were analysed in relation to MACEs (non-fatal MI, stroke, and cardiovascular [CV] mortality), yielding 22,473 events. Hazard ratios (HRs) were estimated using Cox regression. Kaplan–Meier estimates were used to investigate the relationship of MACEs with increasing quintiles of the apoB/apoA-1 ratio in all age groups for both sexes. In nested case–control analyses, cases were randomly matched to age- and sex-matched controls, yielding population trajectories for apolipoproteins. Increased level of apoB and increased apoB/apoA-1 ratio were associated with risk of MACE and all clinical sub-components in both men and women across all ages (10th versus first decile in both sexes combined: HR 1.7 for MACE and 2.7 for non-fatal MI). Decreased values of apoA-1 potentiated the impact of apoB at all levels of apoB (on average across apoB range: 40% increase in HR for MACE and 72% increase in HR for non-fatal MI), indicating that the apoB/apoA-1 ratio covers a broader range of persons with dyslipidaemia at risk than apoB alone. In both men and women, MACEs occurred earlier on average for each increasing quintile of the apoB/apoA-1 ratio. Individuals with the highest levels of apoB/apoA-1 ratio experienced CV events on average several years earlier than those with lower ratios. Higher apoB/apoA-1 ratio in cases of MACE versus controls was seen already about 20 years before the event. A limitation of this study was that adjustment for tobacco smoking and hypertension was only possible in a small validation study.ConclusionsAn imbalance between apoB and apoA-1 resulting in an increased apoB/apoA-1 ratio is strongly associated with the outcome MACE and its sub-components, in both men and women of all ages. An increased apoB/apoA-1 ratio already 2 decades before events calls for early recognition and primary prevention. Simple evidence-based cut values should be considered in future cardiovascular guidelines.

Göran Walldius and colleagues investigate the long-term risk of a major cardiovascular event by apoB, apoA-1 and apoB/apoA-1 ratio in the Swedish AMORIS cohort.     

Incidence of myocardial infarction in elderly men being treated with antihypertensive drugs: population based cohort study.

OBJECTIVE: To analyse the association between use of antihypertensive treatment, diastolic blood pressure, and long term incidence of ischaemic cardiac events in elderly men. DESIGN: Population based cohort study. Baseline examination in 1982-3 and follow up for up to 10 years. SETTING: Malmŏ, Sweden. SUBJECTS: 484 randomly selected men born in 1914 and living in Malmŏ during 1982. MAIN OUTCOME MEASURES: Observational comparisons of incidence rates and rate and hazard ratios of ischaemic cardiac events (myocardial infarction or death due to chronic ischaemic cardiac disease). RESULTS: The crude incidence rate of ischaemic cardiac events was higher in those subjects who were taking antihypertensive drugs than in those who were not (rate ratio 2.6 (95% confidence interval 1.7 to 3.9)). After adjustment for potential confounders (differences in baseline smoking habits, blood pressure, time since diagnosis of hypertension, ischaemic or other cardiovascular disease, hypercholesterolaemia, hypertriglyceridaemia, diabetes mellitus, obesity, and raised serum creatinine concentration) this rate was reduced but still raised (hazard ratio 1.9 (1.0 to 3.7)). In men with diastolic blood pressure > 90 mm Hg, antihypertensive treatment was associated with a twofold increase in the incidence of ischaemic cardiac events (rate ratio 2.0 (1.1 to 3.6)), which vanished after adjustment for potential confounders (hazard ratio 1.1 (0.5 to 2.6)). In those subjects with diastolic blood pressure < or = 90 mm Hg, antihypertensive treatment was associated with fourfold increase in incidence (rate ratio 3.9 (2.1 to 7.1)), which remained after adjustment for potential confounders (hazard ratio 3.8 (1.3 to 11.0)). CONCLUSION: Antihypertensive treatment may increase the risk of myocardial infarction in elderly men with treated diastolic blood pressures < or = 90 mm Hg.     

Insulin resistance in offspring of hypertensive parents.

OBJECTIVE--To determine if insulin resistance is present in normotensive adults at increased risk of developing hypertension. DESIGN--Normotensive subjects with at least one hypertensive parent were paired with offspring of normotensive parents (controls), being matched for age, sex, social class, and physical activity. SETTING--Outpatient clinic. SUBJECTS--30 paired subjects (16 men and 14 women) with and without a family history of hypertension, aged 18-32, with a body mass index < 25 kg/m2, with blood pressure < 130/85 mm Hg, and not taking drugs. INTERVENTIONS--Euglycaemic glucose clamp (two hour infusion of insulin 1 mU/kg/min) and intravenous glucose tolerance test (injection of 100 ml 20% glucose). MAIN OUTCOME MEASURES--Insulin mediated glucose disposal and insulin secretion. RESULTS--The offspring of hypertensive parents had slightly higher blood pressure than did the controls (mean 117 (SD 6) v 108 (5) mm Hg systolic, p = 0.013; 76 (7) v 67 (6) mm Hg diastolic, p = 0.017). Their insulin mediated glucose disposal was lower than that of controls (29.5 (6.5) v 40.1 (8.6) mumol/kg/min, p = 0.002), but, after adjustment for blood pressure, the difference was not significant (difference 6.9 (95% confidence interval -1.5 to 15.3), p = 0.10). Insulin secretion in the first hour after injection of glucose was slightly but not significantly higher in the offspring of hypertensive patients (9320 (5484) v 6723 (3751) pmol.min/l). The two groups had similar concentrations of plasma glucose (5.2 (0.3) v 5.1 (0.4) mmol/l), serum cholesterol (4.4 (0.8) v 4.6 (0.8) mmol/l), serum triglyceride (0.89 (0.52) v 0.68 (0.27) mmol/l), and serum low density lipoprotein cholesterol (2.81 (0.65) v 2.79 (0.61) mmol/l). The offspring of hypertensive parents, however, had lower serum concentrations of high density lipoprotein cholesterol (1.24 (0.31) v 1.56 (0.35) mmol/l, p = 0.002) and higher serum concentrations of non-esterified fatty acids (0.7 (0.4) v 0.4 (0.4) mmol/l, p = 0.039). CONCLUSIONS--Young normotensive subjects who are at increased risk of developing hypertension are insulin resistant.     

Body weight: implications for the prevention of coronary heart disease,stroke, and diabetes mellitus in a cohort study of middle aged men.

OBJECTIVE: To determine the body mass index associated with the lowest morbidity and mortality. DESIGN: Prospective study of a male cohort. SETTING: One general practice in each of 24 British towns. SUBJECTS: 7735 men aged 40-59 years at screening. MAIN OUTCOME MEASURES: All cause death rate, heart attacks, and stroke (fatal and non-fatal) and development of diabetes, or any of these outcomes (combined end point) over an average follow up of 14.8 years. RESULTS: There were 1271 deaths from all causes, 974 heart attacks, 290 strokes, and 245 new cases of diabetes mellitus. All cause mortality was increased only in men with a body mass index (kg/m2) < 20 and in men with an index > or = 30. However, risk of cardiovascular death, heart attack, and diabetes increased progressively from an index of < 20 even after age, smoking, social class, alcohol consumption, and physical activity were adjusted for. For the combined end point the lowest risks were seen for an index of 20.0-23.9. In never smokers and former smokers, deaths from any cause rose progressively from an index of 20.0-21.9 and for the combined end point, from 20.0-23.9. Age adjusted levels of a wide range of cardiovascular risk factors rose or fell progressively from an index < 20. CONCLUSION: A healthy body mass index in these middle aged British men seems to be about 22.