British Regional Heart Study: cardiovascular risk factors in middle-aged men in 24 towns

North-South Gradients in Britain for Stroke and CHD

Background and Purpose— The geographic variation in CHD and stroke within Great Britain is well known. We aimed to quantify these variations and to determine the contribution of established risk factors.

Methods— This prospective study consisted of 7735 men 40 to 59 years of age in 24 British towns who were followed up for 20 years from screening in 1978 to 1980. We compared age-adjusted incidences of major stroke and CHD events in southern England and the rest of Britain before and after adjustment for established cardiovascular risk factors.

Results— At least 1 episode of stroke occurred in 467 men (3.54 per 1000 person-years, age standardized) and of CHD in 1299 men (10.05 per 1000 person-years). Event rates varied between towns, from 2.00 to 5.45 per 1000 person-years for stroke and from 6.16 to 12.21 per 1000 person-years for CHD. Incidence for both diseases was highest in Scottish towns and lowest in southern English towns (“north-south gradient”). The hazard ratio for stroke in the rest of Britain compared with southern England was 1.44 (95% confidence interval [CI], 1.16 to 1.78); for CHD, it was 1.32 (95% CI, 1.14 to 1.53). After adjustment for baseline systolic blood pressure, smoking status, physical activity, social class, and height, the hazard ratio was 1.24 (95% CI, 1.00 to 1.54) for stroke and 1.17 (95% CI, 1.02 to 1.35) for CHD.

Conclusions— Similar north-south gradients were observed for major stroke and major CHD events. The magnitude of these gradients was considerably diminished when individual risk variables were taken into account.

Impact of smoking reduction on coronary heart disease mortality trends during 1981-2000 in England and Wales

Objective

To explore how much of the coronary heart disease (CHD) mortality fall in England and Wales can be attributed to changes in smoking prevalence.

Methods

A previously validated cell-based IMPACT CHD mortality model was used to estimate the deaths prevented or postponed by changes in population smoking prevalence in England and Wales between 1981 and 2000. CHD mortality statistics and population trends in smoking were obtained from routine data sources.

Results

In England and Wales between 1981 and 2000, smoking prevalence in adults aged 25–84 decreased from 43% to 28% in men and from 35% to 24% in women. In men, most of the decrease occurred in those aged over 55. Smoking prevalence changed little in older women. An estimated 29,460 deaths were prevented or postponed (DPP) by this population reduction in smoking prevalence. Most of this benefit was seen in men (86% of the DPPs versus 14% in women).

Conclusion

Large declines in smoking prevalence accounted for 29,460 fewer CHD deaths in England and Wales in 2000 compared with 1981. This emphasises the importance of a national strategy with comprehensive tobacco control programmes to further reduce smoking.

Associations of adult measures of childhood growth with breast cancer: findings from the British Women's Heart and Health Study

Since the two components of adult height - leg length and trunk length - are poorly correlated with each other and appear to be influenced by different early life factors, examining their separate influence on breast cancer may provide additional insights into the mechanisms responsible for the positive association between adult height and breast cancer. In a cross-sectional study of 4286 women aged 60-79 years, in whom there were 170 cases of breast cancer, we found total height, leg length and trunk length were all modestly positively and linearly associated with breast cancer. The magnitudes of the associations of leg and trunk length were similar: fully adjusted odds ratio (95% confidence interval) of breast cancer for a one standard deviation (s.d.) increase in leg length 1.17 (0.98, 1.39) and for a 1 s.d. increase in trunk length 1.19 (0.99, 1.41). Self-reported birth weight (available on 33% of the sample) was positively and linearly associated with breast cancer: fully adjusted odds ratio of breast cancer for a 1 s.d. increase in birth weight 1.30 (0.93, 1.80). These associations were all independent of each other and other potential confounding factors and are likely to reflect different mechanisms by which factors operating prenatally and prepubertally influence breast cancer risk.

Missing, mediocre, or merely obsolete? An evaluation of UK data sources for coronary heart disease

STUDY OBJECTIVE

Coronary heart disease (CHD) is the commonest cause of death in the UK. However, there is no single comprehensive source of information to support CHD prevention and treatment strategies. Therefore this study evaluated the availability and quality of UK CHD data sources since 1981.

DESIGN

Data sources for England and Wales were identified and appraised on: (1) CHD patient numbers (myocardial infarction, angina, hypertension, and heart failure); (2) uptake of medical and surgical CHD treatments, and (3) population trends in major cardiovascular risk factors.

SETTING

England and Wales (population 53 million).

MAIN RESULTS

Population and mortality data were easily accessible from Office for National Statistics and British Heart Foundation Annual CHD Statistics; population based risk factor data came principally from the British Regional Heart Study, the General Household Survey, and the Health Survey for England. They were limited for 1981, but more extensive by 2000. Hospital admissions information since 1998 was available online from HES; but trend data and details of interventions were scant. Limited primary care data on consultation rates, prescribing, and treatment uptake were available from published audits and studies.

CONCLUSIONS

Information on CHD in the UK is fragmented, patchy, and mixed in quality. Data for women, the elderly populatiom, and ethnic minorities were particularly scarce, exacerbating inequalities. Future CHD disease monitoring and evaluation will require comprehensive and accurate population based information on trends in patient numbers, treatment uptake, and risk factors.

Alcohol, body weight, and weight gain in middle-aged men

BACKGROUND

There is uncertainty as to whether regular alcohol consumption contributes directly to weight gain and the risk of obesity.

OBJECTIVE

We examined the relation between alcohol intake and body weight and the association between changes in alcohol intake and in body weight over 5 y of follow-up.

DESIGN

This was a prospective study of 7608 men aged 40-59 y drawn from general practices in 24 British towns, excluding persons with known diabetes. Five years after screening, 6832 men then aged 45-64 y and without diabetes completed a postal questionnaire on changes in alcohol intake and body weight.

RESULTS

Mean body mass index (BMI; in kg/m(2)) and the prevalence of men with a high BMI (>or= 28; top quintile of the BMI distribution) increased significantly from the light-moderate to the very heavy alcohol intake group even after adjustment for potential confounders. Similar patterns were seen for all types and combinations of alcohol. After 5 y of follow-up, stable and new heavy drinkers (including very heavy drinkers of >or= 30 g/d) showed the greatest weight gain and had the highest prevalence rates of high BMI. Weight change patterns in heavy drinkers at baseline who reduced their intake were not significantly different from those in the stable none-occasional group but showed more weight loss and less weight gain than in the stable or new heavy drinkers.

CONCLUSION

Heavy alcohol intake (>or= 30 g/d) contributes directly to weight gain and obesity, irrespective of the type of alcohol consumed.

Fetal programming for adult disease: where next?

The Barker hypothesis of fetal programming for adult cardiovascular and metabolic diseases has attracted much interest over the past few years. In this review, we summarize the main studies in this field, give a brief outline of some of the laboratory models used to investigate this hypothesis and discuss potential mechanisms underlying these clinical observations that are amenable to future research.

Substantial potential for reductions in coronary heart disease mortality in the UK through changes in risk factor levels

STUDY OBJECTIVE

The UK government called for a 40% reduction in cardiovascular disease mortality in those aged under 75 by 2010. This paper examines the potential for cardiovascular risk factor changes to reduce coronary heart disease deaths in Scotland, and then extrapolates the findings to the UK population.

DESIGN

Secondary analysis of published data using a previously validated mortality model. The model combines uptake and effectiveness of treatments with risk factor trends by sex and age group. It was used to estimate the expected reductions in coronary heart disease mortality: (a) if recent risk factor trends simply continued; (b) if additional risk factor reductions were achieved in line with Scandinavia and the United States. An "analysis of extremes" sensitivity analysis was then carried out.

SETTING

Scotland and UK.

PARTICIPANTS

Projected Scottish population aged 45+ in 2010 (2.4 million) and UK population of 26.8 million.

MAIN RESULTS

Continuation of current trends would result in 2169 fewer coronary deaths in 2010 (minimum estimate 1191 from sensitivity analyses to maximum 3870). About 4749 fewer deaths (minimum 3085, maximum 7155) could be achieved by: (a) a reduction in smoking prevalence from 30% to 18% (about 1668 fewer deaths); (b) a mean population cholesterol reduction from 6.2 to 5.2 mmol/l (about 2167 fewer deaths); (c) a 3.7 mm Hg fall in diastolic blood pressure (about 914 fewer deaths). Extrapolation from the Scottish population to the UK suggests 24 000 fewer deaths in 2010 if current trends continue, or 53 000 fewer deaths with the additional reductions.

CONCLUSIONS

With additional interventions it would be possible to almost halve current UK coronary heart disease mortality. Even without gains from medical treatments, the UK government target of 28 000 fewer deaths in 2010 does not seem challenging.

Association between leg length and offspring birthweight: partial explanation for the trans-generational association between birthweight and cardiovascular disease: findings from the British Women's Heart and Health Study

Low birthweight individuals not only have increased risk of cardiovascular disease themselves, but cardiovascular disease risk is also increased in their parents. The mechanisms underlying these trans-generational associations are not fully understood. We hypothesise that, in part, they reflect the trans-generational effects of poor maternal environmental circumstances in early childhood. Adverse environmental factors acting early in the mother's life will not only influence her own predisposition to cardiovascular disease but will also result in adverse consequences - low birthweight and increased cardiovascular disease risk in later life - for her offspring. Adult leg length is a valid indicator of early life environmental circumstances, in particular of infant nutrition. If our hypothesis is correct, then adult leg length should be positively associated with offspring birthweight. In this study of 4286 randomly selected women aged 60-79 years from 23 towns across England, Scotland and Wales, the magnitude of the association between leg length and offspring birthweight was greater than the association between trunk length and offspring birthweight. After control for potential confounding factors, offspring birthweight increased by 89.8 g [95% confidence interval 66.1, 113.5 g] for each standard deviation increase in maternal leg length, and by 55.2 g [32.2, 78.1 g] for each standard deviation increase in maternal trunk length. The association between leg length and offspring birthweight was unaffected by adjustment for maternal birthweight, but the association between trunk length and offspring birthweight was attenuated to 38.0 g [1.0, 74.9 g]. These findings support the hypothesis that adverse early childhood environmental circumstances affect not only the vitality and health of the woman in later life but also the birthweight of her offspring, and suggest that the trans-generational association between birthweight and cardiovascular disease is in part explained by early childhood maternal environmental circumstances.

Is the association between parity and coronary heart disease due to biological effects of pregnancy or adverse lifestyle risk factors associated with child-rearing? Findings from the British Women's Heart and Health Study and the British Regional Heart Study

BACKGROUND

Parity is associated with coronary heart disease (CHD) risk. In the present study, we assessed the associations between number of children and CHD in both women and men.

METHODS AND RESULTS

A total of 4286 women and 4252 men aged 60 to 79 years from 24 British towns were studied. Number of children was positively associated with body mass index and waist-hip ratio in both sexes. In women but not in men, number of children was inversely associated with high-density lipoprotein cholesterol and was positively associated with triglycerides and diabetes. For both sexes, similar "J" shaped associations between number of children and CHD were observed, with the prevalence lowest among those with 2 children and increasing linearly with each additional child beyond 2. For those with at least 2 children, each additional child increased the age-adjusted odds of CHD by 30% (odds ratio, 1.30; 95% confidence interval, 1.17 to 1.44) for women and by 12% for men (odds ratio, 1.12; 95% confidence interval, 1.02 to 1.22). Adjustment for obesity and metabolic risk factors attenuated the associations between greater number of children and CHD in both sexes, although in women some association remained.

CONCLUSIONS

Lifestyle risk factors associated with child-rearing lead to obesity and result in increased CHD in both sexes; biological responses of pregnancy may have additional adverse effects in women.

Geographical variation in cardiovascular disease, risk factors, and their control in older women: British Women's Heart and Health Study

OBJECTIVES

To measure the geographical variation in prevalence of cardiovascular disease, risk factors, and their control in a nationally representative sample of older British women.

METHODS

Baseline survey using general practitioner record review, a self completed questionnaire, research nurse interview, and physical examination in a randomly selected sample of women aged 60-79 drawn from 23 towns in England, Scotland, and Wales.

RESULTS

Of 7,173 women invited and eligible to participate, information was obtained on 4,286 (60%). One in five women had a doctor diagnosis of any one of myocardial infarction, angina, heart failure, stroke, or peripheral vascular disease. Fifty per cent of women were hypertensive, 12% smoked, and over one quarter were obese. Fifty per cent had a total cholesterol level greater than 6.5 mmol/l, though only 3% had low high density lipoprotein concentrations. Cardiovascular disease prevalence varied by geographical region being highest in Scotland: age adjusted prevalence (95% confidence intervals) 25.0% (21.5% to 28.8%) and lowest in South England: age adjusted prevalence (95% confidence intervals) 15.4% (13.5% to 17.6%). The geographical variations in cardiovascular disease prevalence were attenuated by adjustment for risk factors and socioeconomic position; further adjustment for health service use (as indicated by aspirin or statin use) reduced the differences further. However, variation remained even after full adjustment for these factors: odds ratio (95% confidence intervals) comparing Midlands and Wales to South England 1.15 (0.82 to 1.61) and comparing Scotland to South England 1.53 (1.08 to 2.14). Of women with cardiovascular disease, 12% were current smokers, a third had uncontrolled hypertension, a third were obese, and 90% had a blood cholesterol over 5 mmol/l. Only 41% were taking antiplatelet drugs and 22% were taking a statin.

CONCLUSIONS

Older British women have a higher prevalence of cardiovascular disease and risk factors than previously documented. The workload consequences of attempting to control risk factors and ensure optimal secondary prevention for older British women are considerable. Geographical variations in cardiovascular disease prevalence in older women are somewhat, but not fully, explained by variations in major risk factors, socioeconomic position, and health service utilisation.

Migration within Great Britain and cardiovascular disease: early life and adult environmental factors

AIM

To examine the relative contributions of early life and adult life factors to risk of cardiovascular disease (CVD) in middle-aged men using migration within Great Britain (GB).

METHODS

Prospective study of 7,735 men (40-59 years) drawn from one group practice in each of 24 British towns. Zones of birth and/or examination: South of England and rest of GB (Midlands and Wales, North of England, and Scotland).

RESULTS

There were 1,392 coronary heart disease (CHD) events and 1154 cardiovascular deaths during 21.8 years mean follow-up. Regardless of birth zone, men examined in the South showed lower risk of CHD events and CVD mortality than those examined in the rest of GB. Migrants from South to rest of GB showed a small increase in cardiovascular risk. Men born and examined in the rest of GB showed the highest adjusted risk of CHD events (RR = 1.15, 95% CI: 0.96-1.38) and CVD mortality (RR = 1.28, 95% CI: 1.04-1.57). Men born in the rest of GB who moved to the South showed adjusted risks of CHD events and CVD mortality similar to those born and examined in the South. Zone of examination was more strongly associated with CHD events and CVD mortality than zone of birth (RR = 1.23 versus 0.95 for CHD; RR = 1.26 versus 1.04 for CVD mortality). Smokers, irrespective of zone of birth or examination, showed higher risk than non-smokers.

CONCLUSION

Factors in adult life appear to be dominant in determining cardiovascular risk in middle and older age although this does not exclude early life effects on cardiovascular risk.

Birth weight of offspring and insulin resistance in late adulthood: cross sectional survey

OBJECTIVE

To investigate the association between birth weight of offspring and mothers' insulin resistance in late adulthood.

DESIGN

Cross sectional survey.

SETTING

General practitioner's surgeries in 23 towns in Great Britain.

PARTICIPANTS

4286 women aged 60-79 years.

MAIN OUTCOME MEASURES

Maternal insulin resistance.

RESULTS

Birth weight of offspring was inversely related to maternal insulin resistance in late adulthood. For each 1 kg higher birth weight of offspring, women had a 15% reduction in the odds of being in the fourth with highest insulin resistance, compared to other fourths (odds ratio 0.85; 95% confidence interval 0.71 to 1.00). This increased to 27% (0.73; 0.60 to 0.90) after adjusting data for potential confounders. A U shaped relation between birth weight of offspring and diabetes in older age was found; women with the lightest and heaviest offspring had the highest prevalence of diabetes.

CONCLUSIONS

Birth weight of offspring is inversely related to the mother's insulin resistance in late adulthood, despite the association of glucose intolerance during pregnancy with heavier offspring at birth. Common genetic factors contribute to the relation between birth weight and risk of cardiovascular disease and diabetes in adults.

Low prevalence of lipid lowering drug use in older men with established coronary heart disease

OBJECTIVE

To determine the prevalence and correlates of lipid lowering drug use among older British men with established coronary heart disease (CHD).

DESIGN

Cross sectional survey within a cohort study (British regional heart study) carried out at 20 years of follow up in 1998-2000.

SETTING

General practices in 24 British towns.

PARTICIPANTS

3689 men aged 60-75 years (response rate 76%).

MAIN OUTCOME MEASURES

Diagnoses of myocardial infarction and angina based on detailed review of general practice records. Lipid lowering drug use and blood cholesterol concentrations ascertained at 20 year follow up examination.

RESULTS

Among 286 men with definite myocardial infarction, 102 (36%) were taking a lipid lowering drug (93 (33%) a statin); among 360 men with definite angina without myocardial infarction, 84 (23%) were taking a lipid lowering drug (78 (21%) a statin). Most men with documented CHD who were not receiving a lipid lowering drug had a total cholesterol concentration of 5.0 mmol/l or more (87% of those with myocardial infarction, 82% with angina). Fewer than half of men with CHD receiving a statin had a total cholesterol concentration below 5.0 mmol/l (45% of those with myocardial infarction and 47% of those with angina). Only one third of the men taking a statin were receiving trial validated dosages. Among men with CHD, a history of revascularisation, more recent diagnosis, and younger age at diagnosis were associated with a higher probability of receiving lipid lowering drug treatment.

CONCLUSION

Among patients with established CHD, the prevalence of lipid lowering drug use remains low and statin regimens suboptimal. Major improvements in secondary prevention are essential if the benefits of statins are to be realised.

Alcohol consumption and the incidence of type II diabetes

BACKGROUND

This study examines the relation between alcohol and type II diabetes and the possible mediating effects of HDL-cholesterol and serum insulin.

METHODS

Prospective study of 5221 men aged 40-59 years with no history of coronary heart disease, diabetes, or stroke drawn from general practices in 18 British towns.

RESULTS

During the mean follow up of 16.8 years there were 198 incident cases of type II diabetes. Occasional drinkers were the reference group. A non-linear relation was seen between alcohol intake and age adjusted risk of diabetes, with risk lowest in light and moderate drinkers and highest in heavy drinkers (quadratic trend p=0.03). Further adjustment for body mass index decreased risk in heavy drinkers. After additional adjustment for physical activity, smoking, and (undiagnosed) pre-existing coronary heart disease, only moderate drinkers showed significantly lower risk than occasional drinkers (RR=0.66 95% CI 0.44 to 0.99). Alcohol intake was inversely associated with serum insulin and positively associated with HDL-cholesterol. Adjustment for these factors reduced the "protective" effect in moderate drinkers (adjusted RR=0.73 95% CI 0.48 to 1.10) but the quadratic trend remained significant (p=0.02).

CONCLUSION

There is a non-linear relation between alcohol intake and the risk of type II diabetes. Serum insulin and HDL-cholesterol explained a small amount (20%) of the reduction in risk of type II diabetes associated with moderate drinking. The adverse effect of heavy drinking seemed to be partially mediated through its effect on body weight.

Is housework good for health? Levels of physical activity and factors associated with activity in elderly women. Results from the British Women's Heart and Health Study

OBJECTIVE

To determine the prevalence of achieving new recommended levels of physical activity, the types of activity involved, and their determinants among elderly British women.

DESIGN

National cross sectional survey.

PARTICIPANTS

2341 women aged 60 to 79 from 15 British towns.

MAIN OUTCOME MEASURES

Prevalence of subjects achieving recommended levels of physical activity.

RESULTS

Over two thirds of the participants were active at new recommended levels. This was mainly achieved through participation in heavy housework. If domestic activities were excluded only 21% were regularly active. Women who participated in brisk walking for at least 2.5 hours per week had reduced odds of being overweight: odds ratio (95% confidence intervals) 0.5 (0.3 to 0.6) after adjustment for other forms of activity, health status, smoking, and socioeconomic position. Participating in at least 2.5 hours of heavy housework was not associated with reduced odds of being overweight 1.1 (0.8 to 1.4). Age, self reported poor health status, coronary heart disease, and respiratory disease were independently associated with reduced odds of participating in all types of activity. In addition participation in brisk walking and physical exercise were less likely in current smokers, those from the lowest socioeconomic class, and those living in the north of the country. Participation in heavy housework was less likely in women reporting depression but was not associated with smoking, socioeconomic class, or area of residence.

CONCLUSIONS

If new physical activity recommendations, which include domestic activities, are used to assess population levels of physical activity then it seems that the majority of elderly women are sufficiently active. Heavy housework is not associated with reduced levels of being overweight and prospective studies are necessary to demonstrate an independent health benefit of participating in domestic activities.

Physical activity and hemostatic and inflammatory variables in elderly men

BACKGROUND

Physical activity is associated with lower risk of cardiovascular disease, but the mechanisms are uncertain. Hemostatic and inflammatory markers have been linked with risk of cardiovascular disease. We therefore examined the relationship between physical activity and hemostatic and inflammatory variables.

METHODS AND RESULTS

In 1998 to 2000, 20 years after the initial screening of 7735 men 40 to 59 years old from general practices in 24 British towns, 4252 subjects (77% of available survivors, now 60 to 79 old) attended for reexamination. A fasting blood sample was available in 4088 men. All men on warfarin (n=134) and men with incomplete data on physical activity (n=144) were excluded, leaving 3810 men for analysis. Physical activity showed a significant and inverse dose-response relationship with fibrinogen, plasma and blood viscosity, platelet count, coagulation factors VIII and IX, von Willebrand factor, fibrin D-dimer, tissue plasminogen activator antigen, C-reactive protein, and white cell count, even after adjustment for possible confounders. The effects were similar in men with and without prevalent cardiovascular disease. No relationship was seen with activated partial thromboplastin time, activated protein C resistance, hematocrit, or factor VII. An examination of changes in physical activity between baseline and 20 years later showed that inactive men who took up at least light physical activity had levels of blood variables approaching those who remained at least lightly active. Those who became inactive showed levels more similar to those who remained inactive.

CONCLUSIONS

These data suggest that the benefit of physical activity on cardiovascular disease may be at least partly a result of effects on hemostasis and inflammation.

An epidemiological re-appraisal of the association between blood pressure and blood lead: a meta-analysis

Studies on the possible association between blood pressure and blood lead have reached divergent conclusions. In a previous meta-analysis, a doubling of the blood lead concentration was associated with a 1.0/0.6 mm Hg increase in systolic and diastolic blood pressure (BP). This meta-analysis updates the analysis originally performed in 1994. Articles on the association between BP and blood lead were identified from computer searches from January 1980 to February 2001 using the Medical Literature Analysis and Retrieval System. Of the studies reviewed, 31 provided sufficient details to be considered. The meta-analysis included 58518 subjects recruited from the general population in 19 surveys and from occupationally exposed groups in 12 studies. In all but four studies, the results were adjusted for age, and most studies took into account additional confounding factors such as body mass index and the use of alcohol and medication. Weighted joint P-values were calculated using Stouffer's procedure. The association between BP and blood lead was similar in both men and women. In the combined studies, a two-fold increase in blood lead concentration was associated with a 1.0 mm Hg rise in the systolic pressure (95% CI +0.5 to +1.4 mm Hg; P < 0.001) and with a 0.6 mm Hg increase in the diastolic pressure (95% CI +0.4 to +0.8 mm Hg; P < 0.001). On balance, this meta-analysis suggests that there can only be a weak association between BP and blood lead.

Hemodialysis-associated hypertension: pathophysiology and therapy

The majority of end-stage renal disease (ESRD) patients are hypertensive. Hypertension in the hemodialysis patient population is multifactorial. Further, hypertension is associated with an increased risk for left ventricular hypertrophy, coronary artery disease, congestive heart failure, cerebrovascular complications, and mortality. Antihypertensive medications alone do not adequately control blood pressure (BP) in hemodialysis patients. There are, however, several therapeutic options available to normalize BP in these patients, often without the need for additional drug therapy (eg, long, slow hemodialysis; short, daily hemodialysis; nocturnal hemodialysis; or, most effectively, dietary salt and fluid restriction in combination with reduction of dialysate sodium concentration). Optimal BP in dialysis patients is not different from recommendations for the general population, even though definite evidence is not yet available. Predialysis systolic and diastolic BPs are of particular importance. Left ventricular mass correlates with predialysis systolic BP. Survival is better in hemodialysis patients with a mean arterial pressure below 99 mm Hg as compared with those with higher BP. Low predialysis systolic BP (<110 mm Hg) and low predialysis diastolic BP (<70 mm Hg) are associated with increased mortality, primarily because of severe congestive heart failure or coronary artery disease. Patients that experience repeated intradialytic hypotensive episodes should also be viewed with caution, and predialytic BP values should be reevaluated. A possible treatment option for these patients may be slow, long hemodialysis; short, daily hemodialysis; or nocturnal hemodialysis. Among the antihypertensive agents currently available, angiotensin-converting enzyme (ACE) inhibitors appear to have the greatest ability to reduce left ventricular mass. Pressure load can be satisfactorily determined by using the average value of predialysis BP measurements over 1 month. In selected hemodialysis patients, interdialytic ambulatory blood pressure monitoring (ABPM) may help to determine if the patient is in fact hypertensive. In addition, ABPM provides important information about the change in BP between day and night. Regular home BP monitoring, yearly echocardiography, and treatment of traditional risk factors for cardiovascular disease are recommended.

Taking up regular drinking in middle age: effect on major coronary heart disease events and mortality

AIM

To examine effects of taking up regular drinking by middle aged non-drinkers and occasional drinkers on major coronary heart disease events and total mortality.

METHODS

A prospective study of 7735 men from general practices in 24 British towns screened in 1978-80 at age 40-59 years (Q1). Five years after screening, 7157 men then aged 45-64 completed postal questionnaires (Q5) on changes in alcohol intake.

RESULTS

In 6503 men without diagnosed coronary heart disease, there were 874 major coronary heart disease events and 1613 total deaths during 16.8 years of follow up after Q5. With stable occasional drinkers as baseline, men who continued to drink regularly had a significantly lower risk of major coronary heart disease events, coronary heart disease mortality, and overall cardiovascular mortality, but a slightly increased risk of non-cardiovascular mortality. New regular drinkers (89% light), even after adjustment for their many advantageous characteristics, showed a lower risk of major coronary heart disease events than stable occasional drinkers (relative risk (RR) = 0.70; 95% confidence interval (CI) 0.48 to 1.03; p = 0.07). New drinkers showed no reduction in coronary heart disease or cardiovascular mortality and experienced an increase in risk of non-cardiovascular mortality (RR = 1.40; 95% CI 0.99 to 1.97; p = 0.06). In 654 men with diagnosed coronary heart disease, new drinkers experienced no mortality benefit compared with stable occasional drinkers.

CONCLUSIONS

Middle aged new regular drinkers experienced lower risk of major coronary heart disease events than stable occasional drinkers or non-drinkers, but had increased risk of non-cardiovascular mortality and total mortality. These findings provide little support for encouraging older men who do not drink or who only drink occasionally to take up regular drinking, whether or not they have coronary heart disease.

Does self-control account for the relationship between binge drinking and alcohol-related behaviours?

INTRODUCTION

Gottfredson and Hirschi's theory that there is an underlying factor accounting for all sorts of antisocial behaviour has attracted widespread theoretical and empirical attention. One of their most controversial statements is a 'generality' hypothesis, a notion that criminal, deviant and reckless acts are highly correlated because they are caused by individual differences in self-control. In this paper, we examine the extent to which self-control accounts for the relationship between two behaviours: binge drinking and involvement in alcohol-related behaviours, including criminal behaviour.

METHOD

Questionnaires were given to students at a southern US university. A final sample of 241 students (35% males, 91% whites, aged 17-40). One question concerned binge-drinking, 11 others related to other alcohol-related behaviour; a 24-item scale measured self-control and sex was recorded. A probit model was used to test the effect of low self-control on binge drinking and on other alcohol-related behaviours. It was found that self-control exhibits a positive effect on both. But binge drinking and other alcohol-related behaviours are correlated, so a further analysis using a bivariate probit model was undertaken using a naïve model (no covariates), an unconstrained model (allowing self-control to exert a unique effect on both outcomes), and a constrained model forcing self-control to be the same for both outcomes.

RESULTS

Our results suggest that while low self-control is a significant predictor of both binge drinking and alcohol-related problems, it does not fully account for the relationship between the two outcomes. In addition, separate estimation for each sex reveal a substantively different pattern of results.

DISCUSSION

Further research is needed to disentangle the differences between the sexes. Situational factors, especially in males, may account for adverse alcohol-related behaviours. Other measures of self-control are also needed.

Is the prevalence of coronary heart disease falling in British men?

OBJECTIVE

To assess whether long term trends over time in acute coronary heart disease (CHD) event rates have influenced the burden of prevalent CHD in British men.

DESIGN

Longitudinal cohort study.

PARTICIPANTS

7735 men, aged 40-59 at entry (1978-80), selected from 24 British towns.

METHODS

The prevalences of current angina symptoms and history of diagnosed CHD were ascertained by questionnaire in 1978-80, 1983-85, 1992, and 1996. New major CHD events (fatal and non-fatal) were ascertained throughout the study from National Health Service central registers and general practice record reviews. Age adjusted trends in CHD prevalence were compared with trends in major CHD event rates.

RESULTS

From 1978-1996 there was a clear decline in the prevalence of current angina symptoms: the age adjusted annual percentage change in odds was -1.8% (95% confidence interval (CI) -2.8% to -0.8%). However, there was no evidence of a trend in the prevalence of history of diagnosed CHD (annual change in odds 0.1%, 95% CI -1.0% to 1.2%). Over the same period, the CHD mortality rate fell substantially (annual change -4.1%, 95% CI -6.5% to -1.6%); rates of non-fatal myocardial infarction, all major CHD events, and first major CHD event fell by -1.7% (95% CI -3.9% to 0.5%), -2.5% (95% CI -4.1% to -0.8%), and -2.4% (95% CI% -4.3 to -0.4%), respectively.

CONCLUSIONS

These results suggest that middle aged British men are less likely to experience symptoms of angina than in previous decades but are just as likely to have a history of diagnosed CHD. Despite falling rates of new major events and falling symptom prevalence, the need for secondary prevention among middle aged men with established CHD is as great as ever.

Physical activity and risk of cancer in middle-aged men

A prospective study was carried out to examine the relationship between physical activity and incidence of cancers in 7588 men aged 40-59 years with full data on physical activity and without cancer at screening. Physical activity at screening was classified as none/occasional, light, moderate, moderately-vigorous or vigorous. Cancer incidence data were obtained from death certificates, the national Cancer Registration Scheme and self-reporting on follow-up questionnaires of doctor-diagnosed cancer. Cancer (excluding skin cancers) developed in 969 men during mean follow-up of 18.8 years. After adjustment for age, smoking, body mass index, alcohol intake and social class, the risk of total cancers was significantly reduced only in men reporting moderately-vigorous or vigorous activity; no benefit seen at lesser levels. Sporting activity was essential to achieve significant benefit and was associated with a significant dose-response reduction in risk of prostate cancer and upper digestive and stomach cancer. Sporting (vigorous) activity was associated with a significant increase in bladder cancer. No association was seen with colo-rectal cancer. Non-sporting recreational activity showed no association with cancer. Physical activity in middle-aged men is associated with reduced risk of total cancers, prostate cancer, upper digestive and stomach cancer. Moderately-vigorous or vigorous levels involving sporting activities are required to achieve such benefit.

Soluble adhesion molecules and prediction of coronary heart disease: a prospective study and meta-analysis

BACKGROUND

Previous studies have suggested that circulating concentrations of soluble adhesion molecules are useful predictors of risk of coronary heart disease (CHD). Larger studies are needed, however, to test this hypothesis.

METHODS

We measured serum concentrations of four soluble cell adhesion molecules (intercellular adhesion molecule-1 [ICAM-1], vascular cell adhesion molecule-1 [VCAM-1], E-selectin, and P-selectin) in the stored baseline serum samples of 643 men with coronary heart disease and 1278 controls nested in a prospective sutdy of 5661 men who were monitored for 16 years. We also did a meta-analysis of previous relevant studies to place our findings in context.

RESULTS

Concentrations of soluble adhesion molecules were significantly associated with one another, with other markers of inflammation, and with some classic coronary risk factors. For ICAM-1, the odds ratio for CHD was 1.68 (95% CI 1.32-2.14) in a comparison of men in the top third with those in the bottom third of baseline measurements after adjustments for age and town. This decreased to 1.11 (0.75-1.64) after adjustment for some classic coronary risk factors and indicators of socioeconomic status. For the three other cell adhesion molecules, the odds ratios for CHD, first adjusted for age and town only, and then additionally adjusted for other risk factors, were: VCAM-1: 1.26 (0.99-1.61) and 0.96 (0.66-1.40); E-selectin: 1.27 (1.00-1.61) and 1.13 (0.78-1.62); and P-selectin: 1.23 (0.96-1.56) and 1.20 (0.81-1.76).

INTERPRETATION

The measurement of these adhesion molecules is unlikely to add much predictive information to that provided by more established risk factors.

Geographic variation in incidence of coronary heart disease in Britain: the contribution of established risk factors

OBJECTIVE

To determine the extent to which geographic variation in the incidence of major coronary heart disease (CHD) in Great Britain may be explained by established risk factors.

DESIGN

Prospective study.

SETTING

24 British towns with widely differing CHD mortality.

SUBJECTS

7735 men followed up from screening in 1978-80 for 15 years.

MAIN OUTCOME MEASURES

Percentage of variance between the towns in major CHD incidence that can be explained by individual characteristics of men in the towns.

RESULTS

Age standardised incidence rates over a 15 year period varied from 0.52% per annum in Maidstone to 1.07% per annum in Dewsbury and tended to follow the known pattern of higher rates in Scottish and northern English towns and lower rates in southern English towns ("north-south gradient"). Higher town incidence rates were related to prevalence of current cigarette smoking, low physical activity, and low alcohol consumption, and to mean body mass index, mean systolic blood pressure, low mean height, and prevalence of manual social class, but not to mean serum total cholesterol. The 95% range for true age adjusted CHD incidence (over 15 years) was estimated as 0.58-1.03% per annum among British towns. After adjustment for baseline smoking status, physical activity, body mass index, alcohol consumption, systolic blood pressure, serum total cholesterol, occupational social class, and height, this variation was reduced by 50%. A model based on these eight variables accounted for the major part of the north-south gradient.

CONCLUSIONS

Much of the variation in CHD incidence among British towns was accounted for by established risk variables. The remaining unexplained variation may be related to measurement error in the established risk variables, to environmental factors such as climate, or to the combined effect of a wide range of minor risk factors.

Aspirin use for the prevention of cardiovascular disease: the British Women's Heart and Health Study

Low dose aspirin is effective, safe, and economical in the secondary prevention of cardiovascular disease. We have found that only one-third of post-menopausal women with cardiovascular disease are using aspirin and that the majority of women who are using aspirin are doing so for primary prevention. Improvements in this area of medical practice are both necessary and feasible.

Smoking as a modifiable risk factor for type 2 diabetes in middle-aged men

OBJECTIVE

To examine the effects of cigarette smoking, giving up smoking, and primary or secondary pipe or cigar smoking on the risk of type 2 diabetes.

RESEARCH DESIGN AND METHODS

A prospective study followed 7,735 men aged 40-59 years from general practices in 24 British towns for an average of 16.8 years. Incident cases of physician-diagnosed diabetes were ascertained by repeated postal questionnaires and systematic reviews of primary care records.

RESULTS

A total of 290 incident cases of diabetes were found in 7,124 men with no history of diabetes, coronary heart disease, or stroke. Cigarette smoking was associated with a significant increase in risk of diabetes, even after adjustment for age, BMI, and other potential confounders. The benefit of giving up smoking was only apparent after 5 years of smoking cessation, and risk reverted to that of never-smokers only after 20 years. The risk of diabetes in those who switched from smoking cigarettes to pipe or cigars remained equal to the risk in continuing cigarette smokers. Men who gave up smoking during the first 5 years of follow-up showed significant weight gain and subsequently higher risk of diabetes than continuing smokers.

CONCLUSIONS

Cigarette smoking is an independent and modifiable risk factor for type 2 diabetes. Smoking cessation is associated with weight gain and a subsequent increase in risk of diabetes, but in the long term, the benefits of giving up smoking outweigh the adverse effects of early weight gain.

Alcohol and coronary heart disease

The data on two questions are reviewed: does heavy alcohol intake increase the risk of coronary heart disease (CHD)? And, is moderate intake protective? Identified alcoholics and problem drinkers have an increased risk of CHD, and in Britain there is a correlation among 22 towns, between the proportion of heavy drinkers in a town and CHD mortality. Of seven longitudinal studies reviewed, one shows heavy drinkers to have an increased CHD incidence. An inverse association between alcohol consumption and CHD mortality is seen in international comparisons and in time trends in the USA. Of six case-control studies reviewed from England and the USA, all show an inverse association between CHD and alcohol consumption which persists after control for other risk factors. Longitudinal studies, in Japanese-Americans, white American men and women, British civil servants, Puerto Ricans, Yugoslavs and Australians, all show moderate drinkers to have a lower CHD risk than abstainers. Abstainers are likely to differ from moderate drinkers in a number of ways. To date it has not proved possible to show that any of these differences account for the higher CHD risk of abstainers. The apparent protective effect is not large (RR = 0.5) but the consistency of the association and the existence of plausible mechanisms increase the likelihood that the negative association is causal. However, if alcohol intake were to increase in the population the social and medical consequences would be large. An increased intake is therefore not recommended as a community measure for CHD prevention.

Weight change, body weight and mortality: the impact of smoking and ill health

OBJECTIVES

This paper examines the influence of cigarette smoking and ill health on the relationship between weight change, body weight and subsequent mortality to determine whether weight loss and leanness in middle to older age is deleterious to health.

METHODS

Men aged 40-59 years at screening drawn from one general practice in each of 24 British towns, who completed a questionnaire 5 years after screening (Q5) and provided full information on changes in weight and smoking status (n = 7065) were then followed up for an average of 13.8 years.

RESULTS

In all men a shallow U-shaped relationship was seen between body mass index (BMI) at Q5 and all-cause mortality rates. Weight loss and substantial weight gain (> or =10%) were associated with increased mortality rates compared to the stable weight group. The increased risk associated with weight loss was seen in long- term non-smokers (n = 4101) and recent ex-smokers (n = 722) but not in current smokers (n = 2242) after adjustment for a wide range of potential confounders. However, the increased risk was markedly attenuated after exclusion of those with ill health (relative risk [RR] = 1.16, 95% CI : 0.84-1.59 and RR = 0.79, 95% CI : 0.29-2.20 for long-term non-smokers and recent ex-smokers, respectively). Moderate weight gain (4-10%) was associated with lower risk of mortality than observed in those with stable weight but only in recent ex-smokers and in current smokers, not in long-term non-smokers. A positive association was seen between BMI at Q5 and all-cause mortality in non-smokers and this was strengthened by exclusion of men with weight loss.

CONCLUSION

The increased risk of mortality associated with weight loss or low body weight in middle-aged and older men appears to be a direct consequence of ill health leading to weight loss and leanness. In healthy non-smoking men weight loss and leanness are not associated with increased mortality and moderate weight gain (4-10%) was neither deleterious nor beneficial.

Fibrin D-dimer and coronary heart disease: prospective study and meta-analysis

BACKGROUND

It is unknown whether modest increases of fibrin D-dimer, a circulating marker of fibrin turnover, are relevant to coronary heart disease (CHD) in the general population.

METHODS AND RESULTS

We measured serum concentrations of D-dimer antigen in the stored baseline blood samples of 630 CHD cases and 1269 controls "nested" in a prospective cohort of 5661 men who were monitored for 16 years, and we conducted a meta-analysis of previous relevant studies to place our findings in context. In a comparison of men in the top third compared with those in the bottom third of baseline fibrin D-dimer values (tertile cutoffs, >94 versus <49 ng/mL), the odds ratio for CHD was 1.67 (95% CI, 1.31 to 2.13; P<0.0001) after adjustments for age and town. The odds ratio increased slightly after further adjustment for smoking, other classic risk factors, and indicators of socioeconomic status (1.79; 95% CI, 1.36 to 2.36). Strong correlations were observed of fibrin D-dimer values with circulating concentrations of C-reactive protein and serum amyloid A protein but not with smoking, blood lipids, blood pressure, and other risk factors.

CONCLUSION

Although there may be an association between circulating D-dimer values and CHD, further studies are needed to determine the extent to which this is causal.

The use of numbers needed to treat derived from systematic reviews and meta-analysis. Caveats and pitfalls

Numbers needed to treat (NNTs) may be used to present the effects of treatment and are the reciprocal of the absolute difference between treatment and control groups in a randomized controlled trial. NNTs are sensitive to factors that change the baseline risk of trial participants: the outcome considered; characteristics of patients; secular trends in incidence and case-fatality; and clinical setting. NNTs derived from pooled absolute risk differences in meta-analyses are commonly presented and easily calculated by meta-analytic software but may be seriously misleading because of heterogeneity between trials included in meta-analyses. Meaningful NNTs are obtained by applying the pooled relative risk reductions calculated from meta-analyses or individual trials to the baseline risk relevant to specific patient groups. This process will give a range of NNTs depending on whether patients are at high, low, or intermediate levels of risk, rather than a potentially misleading single number.

The effect of the C677T and A1298C polymorphisms in the methylenetetrahydrofolate reductase gene on homocysteine levels in elderly men and women from the British regional heart study

Total blood levels of homocysteine (tHcy) have been shown to depend on both environmental and genetic factors, and to be associated with the risk of developing atherosclerosis with its complications of coronary heart disease (CHD) and stroke. In this study, 408 men and 346 women from two towns, Dewsbury and Maidstone were examined for tHcy levels and genotyped for the C677T and the A1298C polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene. Blood tHcy was significantly higher in men from the CHD high risk town of Dewsbury (12.7 micromol/l) than in the low CHD risk town of Maidstone (11.5 micromol/l) P<0.001, but not in women (10.7 vs. 10.5 micromol/l), with women in both towns, thus, showing significantly lower tHcy than men. There was no difference between towns in folate or vitamin B12 levels but the conventional inverse relationship with tHcy was seen. Smoking men and women from both towns had significantly higher tHcy and lower folate levels than non-smoking individuals (P<0.001). The frequency of the 677T allele in Dewsbury was 0.35 (95% CI; 0.32-0.39) compared with 0.29 (95% CI; 0.26-0.32) in Maidstone (P<0.01). Similar frequency difference of borderline statistical significance was seen both for men (P=0.054) and women (P=0.048) in both the towns, suggesting a true regional frequency difference. The effect of the 677T on tHcy was highly significant in the group as a whole with the most profound effect seen in men (12.0 micromol/l for CC vs. 14.1 micromol/l for TT, P<0.001). By contrast, there was no significant effect of the A1298C polymorphism on tHcy, folate or vitamin B12 levels, with no evidence for an interaction with the C677T genotype. The regional differences in tHcy levels were still present after the adjustment for folate and vitamin B12 levels, smoking and the effect of the C677T polymorphism. This suggests that there may be other unidentified factors, either environmental or genetic, affecting tHcy levels, and thus potentially having an impact on the risk of developing hyperhomocysteinaemia and CHD. These observations may have a bearing on regional differences in tHcy levels and the variation in CHD risk between regions in the UK.

Small area variations in health related behaviours; do these depend on the behaviour itself, its measurement, or on personal characteristics?

In this paper we examine the patterning, by small areas, of four health related behaviours (smoking, alcohol consumption, diet, and exercise) in the West of Scotland, after controlling for a range of individual/household characteristics, using multilevel models. Smoking and drinking were measured both as binary and as continuous variables, and diet and exercise were each measured in two ways: 'good' (health promoting) and 'bad' (health damaging). 'Area effects' (unattributed variation by post code sector) were found for 'bad' diet only. 'Good' and 'bad' diet, 'bad' exercise patterns and current smoking were associated with postcode sector deprivation. For 'bad' diet this effect was found only for individuals in more affluent households, and for 'good' exercise and current smoking the association with area deprivation differed between adolescents and adults. We conclude that the influence of area on health related behaviours varies according to the behaviour and the way it is measured, and that the influence of area deprivation and/or of area can vary by age and household deprivation.

Plasma fibrinogen and factor VII concentrations in adults after prenatal exposure to famine

To assess the effect of maternal malnutrition during different stages of gestation on plasma concentrations of fibrinogen and factor VII, we investigated 725 people, aged 50 years, born around the time of the Dutch famine 1944-5. After adjustment for sex, plasma fibrinogen concentrations differed by -0.01 g/l (95% confidence interval, -0.14-0.11) in those exposed in late gestation, by -0.03 g/l (-0.16-0.11) in those exposed in mid gestation, and by 0.13 g/l (-0.03-0.30) in those exposed in early gestation, compared with non-exposed people (those born before and those conceived after the famine pooled together). Plasma factor VII concentrations differed by 0.4% (-5.4% to 6.6%) in those exposed to famine in late gestation, by 1.5% (-4.6% to 8.1%) in those exposed in mid gestation. and by -11.8% (-18.4 to -4.8%) in those exposed in early gestation, compared with nonexposed people. Size at birth was not associated with plasma concentrations of fibrinogen or factor VII. Our finding that factor VII concentrations were significantly lower in people whose mothers had been exposed to famine in early pregnancy suggests that liver function may be affected by undernutrition in early gestation.

Physical activity and mortality in older men with diagnosed coronary heart disease

BACKGROUND

We have studied the relations between physical activity, types of physical activity, and changes in physical activity and all-cause mortality in men with established coronary heart disease (CHD).

METHODS AND RESULTS

In 1992, 12 to 14 years after the initial screening (Q1) of 7735 men 40 to 59 years of age from general practices in 24 British towns, 5934 (91% of available survivors, mean age 63 years) provided further information on physical activity (Q92) and were followed up for 5 years; 963 had a physician's diagnosis of CHD (myocardial infarction or angina). After exclusions, there were 772 men with established CHD, 131 of whom died of all causes. The lowest risks for all-cause and cardiovascular mortality were seen in light and moderate activity groups (adjusted relative risk compared with inactive/occasionally active: light, 0.42 (0.25, 0.71); moderate, 0.47 (0.24, 0.92); and moderately vigorous/vigorous, 0.63 (0.39, 1.03). Recreational activity of >/=4 hours per weekend, moderate or heavy gardening, and regular walking (>40 min/d) were all associated with a significant reduction in all-cause mortality. Nonsporting activity was more beneficial than sporting activities. Men sedentary at Q1 who began at least light activity by Q92 showed lower mortality rates on follow-up than those who remained sedentary (relative risk 0.58, 95% CI 0.33 to 1.03; P:=0.06).

CONCLUSIONS

Light or moderate activity in men with established CHD is associated with a significantly lower risk of all-cause mortality. Regular walking and moderate or heavy gardening were sufficient to achieve this benefit.

Femoral atherosclerosis in an older British population: prevalence and risk factors

Most estimates of the prevalence of peripheral atherosclerosis have been based on intermittent claudication or lower limb blood flow. The aim of this study was therefore to determine the prevalence of underlying femoral plaque, and to determine its association with other cardiovascular disease and risk factors. Presence of plaque was identified using ultrasound in a random sample of men (n=417) and women (n=367) aged 56-77 years. Coexistent cardiovascular disease, exercise and smoking were determined by questionnaire, blood pressure was recorded, and serum cholesterol and plasma fibrinogen were determined. Of the 784 subjects that were scanned, 502 (64%) demonstrated atherosclerotic plaque. Disease prevalence increased significantly with age (P<0.0001), and was more common in men (67.1 vs. 59.4%, P<0.05). Subjects with femoral plaque had a significantly greater odds of previous ischaemic heart disease (OR 2. 2, 95% CI 1.3, 3.7) and angina (OR 1.7, 95% CI 1.03, 2.7), but not of stroke or leg pain on exercise. Current and ex-smoking, raised serum total cholesterol and plasma fibrinogen levels, but not blood pressure, were associated with an increased risk of femoral plaque, independent of age and sex. Frequent exercise and a high HDL cholesterol were significantly associated with lower risk. In conclusion, therefore, atherosclerotic disease of the femoral artery affects almost two-thirds of the population in late middle age. It is associated with an increased prevalence of ischaemic heart disease and angina, but whether detecting at risk individuals using ultrasound offers advantages over simpler and less expensive risk factor scoring requires evaluation in trials.

HDL-Cholesterol, total cholesterol, and the risk of stroke in middle-aged British men

BACKGROUND AND PURPOSE

The purpose of this study was to examine the relation between serum HDL cholesterol and total cholesterol and risk of stroke.

METHODS

We carried out a prospective study in 7735 men, 40 to 59 years of age, drawn from 1 group practice in each of 24 British towns. Men with history of stroke were excluded (n=52).

RESULTS

During the mean follow-up period of 16.8 years, there were 343 stroke cases (fatal and nonfatal) in the 7683 men with no history of stroke. Higher levels of HDL cholesterol were associated with a significant decrease in risk of stroke even after adjustment for potential confounders (top fifth versus lowest fifth: adjusted relative risk=0.68, 95% CI 0.46 to 0.99). The inverse relation was seen only for nonfatal strokes (adjusted relative risk=0.59, 95% CI 0.39 to 0.90; top fifth versus lowest fifth). Total cholesterol showed no graded association with fatal strokes, but men with levels > or =8.1 mmol/L (top 5% of the distribution) showed increased risk of nonfatal stroke, although this was not statistically significant after adjustment (adjusted RR=1.46, 95% CI 0.91 to 2.32). The beneficial effects of elevated HDL cholesterol on nonfatal stroke were seen in both smokers and nonsmokers and were more evident in men with hypertension than in normotensives. In hypertensive men, elevated HDL cholesterol (top fifth) was associated with a significant 50% reduction in risk of nonfatal strokes compared with men in the lowest fifth.

CONCLUSIONS

Higher levels of HDL cholesterol were associated with a significant decrease in risk of nonfatal stroke. In contrast, elevated total cholesterol showed a weak positive association with nonfatal strokes. The marked inverse association between HDL cholesterol and stroke seen in hypertensives emphasizes the importance of those modifiable risk factors for stroke known to lower the concentrations of HDL cholesterol.

Low grade inflammation and coronary heart disease: prospective study and updated meta-analyses

OBJECTIVE

To assess associations between baseline values of four different circulating markers of inflammation and future risk of coronary heart disease, potential triggers of systemic inflammation (such as persistent infection), and other markers of inflammation.

DESIGN

Nested case-control comparisons in a prospective, population based cohort.

SETTING

General practices in 18 towns in Britain.

PARTICIPANTS

506 men who died from coronary heart disease or had a non-fatal myocardial infarction and 1025 men who remained free of such disease until 1996 selected from 5661 men aged 40-59 years who provided blood samples in 1978-1980.

MAIN OUTCOME MEASURES

Plasma concentrations of C reactive protein, serum amyloid A protein, and serum albumin and leucocyte count. Information on fatal and non-fatal coronary heart disease was obtained from medical records and death certificates.

RESULTS

Compared with men in the bottom third of baseline measurements of C reactive protein, men in the top third had an odds ratio for coronary heart disease of 2.13 (95% confidence interval 1.38 to 3.28) after age, town, smoking, vascular risk factors, and indicators of socioeconomic status were adjusted for. Similar adjusted odds ratios were 1.65 (1.07 to 2.55) for serum amyloid A protein; 1.12 (0.71 to 1.77) for leucocyte count; and 0.67 (0.43 to 1.04) for albumin. No strong associations were observed of these factors with Helicobacter pylori seropositivity, Chlamydia pneumoniae IgG titres, or plasma total homocysteine concentrations. Baseline values of the acute phase reactants were significantly associated with one another (P<0.0001), although the association between low serum albumin concentration and leucocyte count was weaker (P=0.08).

CONCLUSION

In the context of results from other relevant studies these findings suggest that some inflammatory processes, unrelated to the chronic infections studied here, are likely to be involved in coronary heart disease.

High prevalence of potentially virulent strains of Helicobacter pylori in the general male British population

BACKGROUND

Strains of Helicobacter pylori that express the cytotoxin associated gene product A (CagA) may be more strongly associated with serious gastric diseases, such as gastric cancer and peptic ulceration, than other strains. Data, however, are sparse on the prevalence, risk factors, and other correlates of these strains in the general population.

AIM

To characterise aspects of the seroepidemiology of CagA(+) strains of H pylori in the general British population.

METHODS

We measured serum IgG antibodies to mixed H pylori antigens and separately to CagA in 1025 men aged 40-59 years who were randomly selected from a larger group of participants in a community based survey conducted in 18 different British towns.

RESULTS

Overall, 44% (95% confidence interval 41-47%) of the men were seropositive to CagA antibodies, representing about 61% (57-65%) of the men seropositive to mixed antigen H pylori. The risk factors for seropositivity to CagA antibodies were similar to those for seropositivity to mixed antigen H pylori, apart from an increased prevalence of reported bedroom sharing in childhood (p<0.01).

CONCLUSION

In a nationwide study of potentially virulent H pylori strains, there was a high prevalence of the infection, with some evidence that acquisition of such strains might occur earlier in life than other strains.

A rational approach to drug therapy of type 2 diabetes mellitus

Several new pharmacological agents have recently been developed to optimise the management of type 2 (non-insulin-dependent) diabetes mellitus. The aim of this article is to briefly review the various therapeutic agents available for management of patients with type 2 diabetes mellitus and to suggest a potential approach to drug selection. There are three general therapeutic modalities relevant to diabetes care. The first modality is lifestyle adjustments aimed at improving endogenous insulin sensitivity or insulin effect. This can be achieved by increased physical activity and bodyweight reduction with diet and behavioural modification, and the use of pharmacological agents or surgery. This first modality is not discussed in depth in this article. The second modality involves increasing insulin availability by the administration of exogenous insulin, insulin analogues, sulphonylureas and the new insulin secretagogue, repaglinide. The most frequently encountered adverse effect of these agents is hypoglycaemia. Bodyweight gain can also be a concern, especially in patients who are obese. The association between hyperinsulinaemia and premature atherosclerosis is still a debatable question. The third modality consists of agents such as biguanides and thiazolidinediones which enhance insulin sensitivity, or agents that decrease insulin requirements like the alpha-glucosidase inhibitors. Type 2 diabetes mellitus is a heterogeneous disease with multiple underlying pathophysiological processes. Therapy should be individualised based on the degree of hyperglycaemia, hyperinsulinaemia or insulin deficiency. In addition, several factors have to be considered when prescribing a specific therapeutic agent. These factors include efficacy, safety, affordability and ease of administration.

Growth in utero and blood pressure levels in the next generation

OBJECTIVE

To determine whether blood pressure levels in adult life are related to the mother's fetal growth and size at birth.

DESIGN

A follow-up study of men and women whose mothers' or fathers' size at birth was recorded in Preston, Lancashire, UK.

SUBJECTS

Two hundred and twenty-eight men and women born in Preston, Lancashire, UK, and still living in Lancashire.

MAIN OUTCOME MEASURES

Blood pressure at 18-40 years of age.

RESULTS

Systolic and diastolic pressures fell with increasing mother's birthweight and head circumference. Systolic pressure fell by 2.4 mmHg (95% confidence interval (CI) 0.1-4.7) for each pound increase in mother's birthweight and by 4.0 mmHg (95% CI 0.2-7.8) for each one inch increase in head circumference. These associations were little changed by adjusting for length of gestation or for the subject's age, sex, body mass index or alcohol consumption. They were independent of the mother's blood pressure. As expected, mothers' birthweights were strongly related to their children's birthweights (P= 0.009), but the association between mother's birthweight and offspring's blood pressure was largely independent of this. Father's size at birth was not related to the offspring's blood pressure.

CONCLUSIONS

If the growth of a female fetus is constrained by lack of nutrients, there are persisting changes in her physiology and metabolism which lead to reduced fetal growth and raised blood pressure in the next generation. Public health policies to improve fetal growth in one generation may therefore benefit succeeding generations as well.

A longitudinal survey of the evolution of some cardiovascular risk factors during the careers of male firefighters retiring from Strathclyde Fire Brigade from 1985-1994

This paper is based on a retrospective survey of the cardiovascular risk factor records of 526 wholetime male firefighters retiring from Strathclyde Fire Brigade during the decade beginning 1 January 1985 who had accumulated 14,022 man-years of service. Changes in body mass index (BMI) and systolic & diastolic blood pressure (S&DBP) were observed from enlistment and through the triennial routine medical examinations (RME) which took place from age 40 to retirement, usually occurring after age 50. Tobacco consumption, electrocardiographic abnormalities, and fasting lipid levels were checked at each RME. The findings were then subdivided into quinquennia. Mean BMI(+/- 1 SD) increased from 23.4(2.6) at enlistment to 26.6(3.2) at retirement with the proportion of those obese (BMI > = 30) changing from 1.8% to 17.2% respectively. Systolic and diastolic BP also rose throughout the study from 126(7.14) and 77(7.11) to 137(16.9) and 87(10.9). No subjects had BP > 160 or > 110 at enlistment but, on retirement, this had been attained by 7.2 and 2.1%. Mean cholesterol and triglyceride levels rose from 5.23(0.70) to 6.21(1.09) and 1.65(0.67) to 1.93(1.32). HDL cholesterol fell from 1.71(0.35) to 1.37(0.46). The proportion of non-smokers rose from 35.9 to 48.9%. When the results were analysed by quinquennia, statistically significant differences at retirement were found for BMI, S&DBP, and triglycerides. This would suggest that health education activities have not been effective in this workforce.

Distribution and determinants of ischaemic heart disease in an urban population. A study from the myocardial infarction register in Malmö, Sweden

OBJECTIVE

Age adjusted incidence of myocardial infarction has been found to vary substantially between the residential areas of the city of Malmö. The objective of this study was to assess the extent to which major biological risk factors and socio-economic circumstances account for the differences in incidence of and mortality from myocardial infarction.

DESIGN

Ecological study of risk factor prevalence and incidence and mortality from myocardial infarction.

SETTING

Seventeen administrative areas in Malmö, Sweden.

SUBJECTS

Assessment of risk factor prevalence was based on 28 466 men and women, ranging from 45 to 73 years old, who were recruited as participants in the Malmö Diet and Cancer study. Information on serum lipids was available in a random subsample of 5362 subjects. Information about socio-economic level of the residential area was based on statistics from the Malmö City Council and Statistics Sweden.

MAIN OUTCOME MEASURES

Weighted least square regressions between prevalence of risk factors (i.e. smoking, hypertension, obesity, diabetes, hypercholesterolemia and hypertriglyceridemia), a myocardial infarction risk score, a socio-economic score and incidence and mortality from myocardial infarction.

RESULTS

The risk factor prevalence and myocardial infarction incidence was highest in areas with low socio-economic level. Prevalence of smoking, obesity and hypertension was significantly associated with myocardial infarction incidence and mortality rates amongst men (all r > 0.60). Prevalence of smoking was significantly associated with incidence and mortality from myocardial infarction amongst women (r = 0.66 and r = 0.61, respectively). A myocardial infarction risk score based on four biological risk factors explained 40-60% of the intra-urban geographical variation in myocardial infarction incidence and mortality. The socio-economic score added a further 2-16% to the explained variance.

CONCLUSION

In an urban population with similar access to medical care, well-known biological cardiovascular risk factors account for a substantial proportion of the intra-urban geographical variation of incidence of and mortality from myocardial infarction. The socio-economic circumstances further contribute to the intra-urban variation in disease.

Prospective study of potentially virulent strains of Helicobacter pylori and coronary heart disease in middle-aged men

BACKGROUND

Studies are needed to test claims that potentially virulent strains of Helicobacter pylori are more strongly related to coronary heart disease (CHD) than are other strains.

METHODS AND RESULTS

We measured serum IgG antibodies to mixed H pylori antigens and separately to the virulence-associated H pylori antigen CagA (cytotoxin-associated gene product A) in 505 CHD cases and in 1025 age-matched controls "nested" in a prospective study of 7735 British men (mean duration of follow-up in controls, 16 years). Of the 505 cases, 401 (79%) were seropositive for H pylori antibodies compared with 740 (72%) of the 1025 controls, yielding an odds ratio for CHD of 1.55 (95% CI 1.19 to 2.03), which fell to 1.30 (95% CI 0.88 to 1. 90) after adjustments were made for standard vascular risk factors and indicators of socioeconomic status. Of the CHD cases, 240 (48%) were seropositive for IgG antibodies to CagA compared with 450 (44%) of the controls. When CagA-seropositive individuals were compared with H pylori-seronegative individuals, the odds ratio for CHD was 1. 42 (95% CI 1.06 to 1.91), which fell to 1.10 (95% CI 0.71 to 1.71) after adjustments. In an analysis restricted to the 1141 (75%) H pylori-seropositive participants, the odds ratio for CHD was 1.0 (95% CI 0.78 to 1.29) in CagA-seropositive men. No strong associations were observed between H pylori seropositivity and blood lipids, blood pressure, markers of systemic inflammation, or plasma homocysteine.

CONCLUSIONS

H pylori infection is not strongly related to the incidence of CHD in late middle-aged men, and CagA-positive strains appear to be no more strongly related to the disease than other strains. However, further studies are required to confirm or refute the existence of any moderate associations, particularly at younger ages.

Regional variation in incidence and case fatality of myocardial infarction among young women in England, Scotland and Wales

OBJECTIVES

To examine the regional variation in incidence and case fatality of myocardial infarction among young women.

DESIGN

Cross sectional survey, using population based incidence data.

SETTING

England, Scotland and Wales.

SUBJECTS

Subjects were women aged 16-44 with a diagnosis of myocardial infarction between 1 October 1993 and 15 October 1995.

OUTCOME MEASURES

Incidence of myocardial infarction per 100,000 women years, with case fatality as a percentage of total cases.

RESULTS

Incidence of myocardial infarction rose steeply from age 33 upwards, (maximum = 20.2 cases per 100,000 women years at age 44). The adjusted incidence rate for myocardial infarction was 3.7 (95% CI 3.2, 4.2) times greater in Scotland than in southern England. In contrast, case fatality was significantly lower in Scotland: 18.5% (95% CI 13.1%, 25.0%), compared with 31.0% (95% CI 25.9%, 36.0%) in southern England.

CONCLUSIONS

The incidence of myocardial infarction varied widely within the United Kingdom. Case fatality variation may reflect differences in ambulance response, or in diagnostic acumen, within the regions.

Alcohol intake and mortality in middle aged men with diagnosed coronary heart disease

OBJECTIVE

To examine the effects of alcohol on risk of mortality from coronary heart disease (CHD), cardiovascular disease, and all causes in men with established CHD.

METHODS AND RESULTS

In a population based prospective study of 7169 men aged 45-64 years followed for a mean of 12.8 years, 655 men (9.1%) had a physician diagnosis of CHD (myocardial infarction 455, angina only 200). In these 655 men, there were 294 deaths from all causes including 175 CHD deaths. Ex-drinkers had the highest risk of CHD, cardiovascular mortality, and all cause mortality even after adjustment for lifestyle characteristics and pre-existing disease. Using occasional drinkers as the reference group, lifelong teetotallers, occasional drinkers, and light drinkers all showed similar risks of mortality from CHD, cardiovascular disease, and all causes. Moderate/heavy drinkers showed increased risk of mortality from CHD, cardiovascular disease, and all causes compared to occasional drinkers. The adverse effect of moderate/heavy drinking was confined to the 455 men with previous myocardial infarction (adjusted relative risk for all cause mortality 1.50, 95% confidence interval 1.01 to 2.23). In contrast to lighter drinking, giving up smoking within five years of the start of follow up was associated with a considerable reduction in risk of all cause and cardiovascular mortality compared to those who continued to smoke.

CONCLUSION

Compared to occasional drinking, regular light alcohol consumption (1-14 units per week) in men with established coronary heart disease is not associated with any significant benefit or deleterious effect for CHD, cardiovascular disease or all cause mortality. Higher levels of intake (>/= 3 drinks per day) are associated with increased mortality in men with previous myocardial infarction. In contrast, smoking cessation in men with established CHD substantially reduces the risk of mortality.

Obesity is an environmental issue

Obesity is an environmental issue. Societies that are transitioning to westernized lifestyles are experiencing substantial increases in its prevalence. The primary environmental determinants of obesity are high calorie intake and low levels of activity. Socioeconomic status and place of residence are important contributors. These factors together comprise an obesogenic or 'toxic' environment where the development of obesity is the expected course for humans leading lifestyles incompatible with their evolutionary development. Only by addressing and modifying the toxic environment will we be able to stem the obesity epidemic.

Serum total homocysteine and coronary heart disease: prospective study in middle aged men

OBJECTIVES

To examine the prospective relation between total homocysteine and major coronary heart disease events.

DESIGN

A nested case-control study carried out within the British regional heart study, a prospective investigation of cardiovascular disease in men aged 40-59 years at entry. Serum total homocysteine concentrations were analysed retrospectively and blindly in baseline samples from 386 cases who had a myocardial infarct during 12.8 years of follow up and from 454 controls, frequency matched by age and town.

RESULTS

Geometric mean serum total homocysteine was slightly higher in cases (14.2 micromol/l) than in controls (13.5 micromol/l), a proportional difference of 5.5% (95% confidence interval (CI) -0.02% to 10.8%, p = 0.06). Age adjusted risk of myocardial infarction increased weakly with log total homocysteine concentration; a 1 SD increase in log total homocysteine (equivalent to a 47% increase in total homo cysteine) was associated with an increase in odds of myocardial infarction of 1.15 (95% CI 1.00 to 1. 32; p = 0.05). The relation was particularly marked in the top fifth of the total homocysteine distribution (values >16.5 micromol/l), which had an odds ratio of 1.77 (95% CI 1.28 to 2.42) compared with lower levels. Adjustment for other risk factors had little effect on these findings. Total homocysteine concentrations more than 16.5 micromol/l accounted for 13% of the attributable risk of myocardial infarction in this study population. Serum total homocysteine among control subjects varied between towns and was correlated with town standardised mortality ratios for coronary heart disease (r = 0.43, p = 0.08).

CONCLUSIONS

Serum total homocysteine is prospectively related to increased coronary risk and may also be related to geographical variation in coronary risk within Britain. These results strengthen the case for trials of total homocysteine reduction with folate.