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

Can metabolic syndrome usefully predict cardiovascular disease and diabetes? Outcome data from two prospective studies

BACKGROUND

Clinical use of criteria for metabolic syndrome to simultaneously predict risk of cardiovascular disease and diabetes remains uncertain. We investigated to what extent metabolic syndrome and its individual components were related to risk for these two diseases in elderly populations.

METHODS

We related metabolic syndrome (defined on the basis of criteria from the Third Report of the National Cholesterol Education Program) and its five individual components to the risk of events of incident cardiovascular disease and type 2 diabetes in 4812 non-diabetic individuals aged 70-82 years from the Prospective Study of Pravastatin in the Elderly at Risk (PROSPER). We corroborated these data in a second prospective study (the British Regional Heart Study [BRHS]) of 2737 non-diabetic men aged 60-79 years.

FINDINGS

In PROSPER, 772 cases of incident cardiovascular disease and 287 of diabetes occurred over 3.2 years. Metabolic syndrome was not associated with increased risk of cardiovascular disease in those without baseline disease (hazard ratio 1.07 [95% CI 0.86-1.32]) but was associated with increased risk of diabetes (4.41 [3.33-5.84]) as was each of its components, particularly fasting glucose (18.4 [13.9-24.5]). Results were similar in participants with existing cardiovascular disease. In BRHS, 440 cases of incident cardiovascular disease and 105 of diabetes occurred over 7 years. Metabolic syndrome was modestly associated with incident cardiovascular disease (relative risk 1.27 [1.04-1.56]) despite strong association with diabetes (7.47 [4.90-11.46]). In both studies, body-mass index or waist circumference, triglyceride, and glucose cutoff points were not associated with risk of cardiovascular disease, but all five components were associated with risk of new-onset diabetes.

INTERPRETATION

Metabolic syndrome and its components are associated with type 2 diabetes but have weak or no association with vascular risk in elderly populations, suggesting that attempts to define criteria that simultaneously predict risk for both cardiovascular disease and diabetes are unhelpful. Clinical focus should remain on establishing optimum risk algorithms for each disease.

Social engagement and the risk of cardiovascular disease mortality: results of a prospective population-based study of older men

PURPOSE

To examine the prospective relation of social engagement with cardiovascular disease (CVD) mortality, taking into account behavioral factors (smoking, physical activity, body weight, and alcohol consumption), socioeconomic factors, and presence of comorbidity and disability.

METHODS

A socioeconomically representative cohort of 5925 men aged 52-74 years from 24 British towns was followed up from 1992-2006. A scale from 0-9 was used based on questions reflecting the frequency and extent of social engagement in 1992.

RESULTS

CVD mortality risk decreased with increasing social engagement score-age-adjusted hazard ratio (HR) for those with the highest social engagement score of 8-9 was 0.42 (95% confidence interval [95%CI], 0.32-0.53) compared to those with the lowest scores of 0-3 (p for trend < or = 0.0001). Further adjustment for behavioral factors (smoking, alcohol, physical activity, and body weight), disability, comorbidity, and socioeconomic factors reduced the strength of this association, although strong evidence of an association remained: HR 0.70 (95%CI, 0.53-0.93) for highest versus lowest social engagement scores (p for trend = 0.0004). Although the association appeared somewhat stronger in subjects with preexisting CVD (HR 0.59 for highest vs. lowest social engagement scores) than in those without (HR 0.79), there was no evidence of an interaction between social engagement and preexisting CVD (p = 0.61).

CONCLUSIONS

In our study of older men, social engagement appeared to have a modest protective effect on CVD mortality independent of behavioral factors, socioeconomic conditions, disease, and disability.

Tissue plasminogen activator, von Willebrand factor, and risk of type 2 diabetes in older men

OBJECTIVE

The objective of this study was to assess the relationship between putative markers of endothelial dysfunction (tissue plasminogen activator [t-PA] antigen and von Willebrand factor [vWF] antigen) and development of type 2 diabetes, as well as the role of inflammation, adipokines, hepatic function, and insulin resistance in modifying these relationships.

RESEARCH DESIGN AND METHODS

This was a prospective study of 3,562 nondiabetic men aged 60-79 years followed up for an average of 7 years during which there were 162 incident cases of type 2 diabetes.

RESULTS

Elevated t-PA (top third) was associated with a near threefold increase in risk of diabetes compared with the risk in those in the bottom third after adjustment for lifestyle factors and waist circumference (relative risk [RR] 2.98 [95%CI 1.79-5.00]; P(trend) < 0.0001); weaker but significant (marginal) associations were seen with vWF (1.24 [0.83-1.85]; P = 0.05 for trend). Both biomarkers of endothelial dysfunction correlated significantly with markers of inflammation (interleukin-6 [IL-6] and C-reactive protein [CRP]), hepatic function (gamma-glutamyl transferase [GGT]), and insulin resistance, with t-PA showing stronger associations with adiposity, hepatic function, and insulin resistance than vWF. t-PA was also significantly and inversely associated with adiponectin. Adjustment for IL-6, adiponectin, and GGT attenuated the association of incident diabetes with vWF (1.06 [0.71-1.60]), but the relationship seen with t-PA remained significant (adjusted RR 2.19 [1.29-3.70]). Subsequent adjustment for insulin attenuated the association further, but t-PA was still associated with a significant increase in risk (1.66 [0.96-2.85]; P(trend) = 0.02).

CONCLUSION

t-PA antigen, but not vWF antigen, is independently associated with risk of type 2 diabetes.

The value of gamma-glutamyltransferase in cardiovascular risk prediction in men without diagnosed cardiovascular disease or diabetes

AIMS

We have examined the relationship between gamma-glutamyltransferase (GGT) and major coronary heart disease (CHD) and stroke events and cardiovascular mortality in men free of cardiovascular disease (CVD).

METHODS

A prospective study of 6997 men aged 40-59 with no history of CVD (CHD or stroke) or diabetes drawn from general practices in 24 British towns and followed up for 24 years.

RESULTS

GGT was significantly and positively associated with increased risk of fatal (but not non-fatal CHD events), major stroke events and total CVD mortality after adjustment for established CVD risk factors. Risk of fatal CHD and CVD mortality was only elevated in the top quarter (22IU/L); risk of stroke tended to increase with increasing GGT. The adjusted relative risks (Q4 vs. Q1) were 1.43 (1.09,1.84) for fatal CHD events, 1.56 (1.20,2.04) for stroke incidence and 1.40 (1.16,1.70) for CVD mortality. When stratified by age groups stronger associations were seen between GGT and CVD mortality in the younger men (<55 years) (p=0.01 for interaction). GGT significantly predicted CVD outcomes especially in those at low and medium CHD risk based on Framingham risk score (FRS).

CONCLUSION

Elevated GGT is associated with significantly increased risk of stroke, fatal CHD events and CVD mortality independent of established CVD risk factors and may be a useful additional marker for long-term CVD risk.

A coronary heart disease risk model for predicting the effect of potent antiretroviral therapy in HIV-1 infected men

BACKGROUND

Many HIV-infected patients on highly active antiretroviral therapy (HAART) experience metabolic complications including dyslipidaemia and insulin resistance, which may increase their coronary heart disease (CHD) risk. We developed a prognostic model for CHD tailored to the changes in risk factors observed in patients starting HAART.

METHODS

Data from five cohort studies (British Regional Heart Study, Caerphilly and Speedwell Studies, Framingham Offspring Study, Whitehall II) on 13,100 men aged 40-70 and 114,443 years of follow up were used. CHD was defined as myocardial infarction or death from CHD. Model fit was assessed using the Akaike Information Criterion; generalizability across cohorts was examined using internal-external cross-validation.

RESULTS

A parametric model based on the Gompertz distribution generalized best. Variables included in the model were systolic blood pressure, total cholesterol, high-density lipoprotein cholesterol, triglyceride, glucose, diabetes mellitus, body mass index and smoking status. Compared with patients not on HAART, the estimated CHD hazard ratio (HR) for patients on HAART was 1.46 (95% CI 1.15-1.86) for moderate and 2.48 (95% CI 1.76-3.51) for severe metabolic complications.

CONCLUSIONS

The change in the risk of CHD in HIV-infected men starting HAART can be estimated based on typical changes in risk factors, assuming that HRs estimated using data from non-infected men are applicable to HIV-infected men. Based on this model the risk of CHD is likely to increase, but increases may often be modest, and could be offset by lifestyle changes.

Decreased muscle mass and increased central adiposity are independently related to mortality in older men

BACKGROUND

Aging is associated with significant changes in body composition. Body mass index (BMI; in kg/m(2)) is not an accurate indicator of overweight and obesity in the elderly.

OBJECTIVE

We examined the relation between other anthropometric indexes of body composition (both muscle mass and body fat) and all-cause mortality in men aged 60-79 y.

DESIGN

The study was a prospective study of 4107 men aged 60-79 y with no diagnosis of heart failure and who were followed for a mean period of 6 y, during which time there were 713 deaths.

RESULTS

Underweight men (BMI < 18.5) had exceptionally high mortality rates. After the exclusion of these men, increased adiposity [BMI, waist circumference (WC), and waist-to-hip ratio] showed little relation with mortality after adjustment for lifestyle characteristics. Muscle mass [indicated by midarm muscle circumference (MAMC)] was significantly and inversely associated with mortality. After adjustment for MAMC, obesity markers, particularly high WC (>102 cm) and waist-to-hip ratio (top quartile), were associated with increased mortality. A composite measure of MAMC and WC most effectively predicted mortality. Men with low WC (</=102 cm) and above-median muscle mass showed the lowest mortality risk. Men with WC > 102 cm and above-median muscle mass showed significantly increased mortality [age-adjusted relative risk: 1.36; 95% CI: 1.07, 1.74), and this increased to 1.55 (95% CI: 1.01, 2.39) in those with WC > 102 and low MAMC.

CONCLUSION

The findings suggest that the combined use of both WC and MAMC provides simple measures of body composition to assess mortality risk in older men.

The Emerging Risk Factors Collaboration: analysis of individual data on lipid, inflammatory and other markers in over 1.1 million participants in 104 prospective studies of cardiovascular diseases

Many long-term prospective studies have reported on associations of cardiovascular diseases with circulating lipid markers and/or inflammatory markers. Studies have not, however, generally been designed to provide reliable estimates under different circumstances and to correct for within-person variability. The Emerging Risk Factors Collaboration has established a central database on over 1.1 million participants from 104 prospective population-based studies, in which subsets have information on lipid and inflammatory markers, other characteristics, as well as major cardiovascular morbidity and cause-specific mortality. Information on repeat measurements on relevant characteristics has been collected in approximately 340,000 participants to enable estimation of and correction for within-person variability. Re-analysis of individual data will yield up to approximately 69,000 incident fatal or nonfatal first ever major cardiovascular outcomes recorded during about 11.7 million person years at risk. The primary analyses will involve age-specific regression models in people without known baseline cardiovascular disease in relation to fatal or nonfatal first ever coronary heart disease outcomes. This initiative will characterize more precisely and in greater detail than has previously been possible the shape and strength of the age- and sex-specific associations of several lipid and inflammatory markers with incident coronary heart disease outcomes (and, secondarily, with other incident cardiovascular outcomes) under a wide range of circumstances. It will, therefore, help to determine to what extent such associations are independent from possible confounding factors and to what extent such markers (separately and in combination) provide incremental predictive value.

Missed opportunities for secondary prevention of cerebrovascular disease in elderly British men from 1999 to 2005: a population-based study

OBJECTIVE

We examined patterns in medication use for secondary prevention of cerebrovascular disease in older British men from 1999 to 2005, and investigated socio-demographic and disease-related influences on medication use.

METHODS

Percentage use of antiplatelet drugs, blood pressure-lowering drugs and statins use was calculated in men, aged 65-87 years in 2005, who had been diagnosed with stroke or transient ischaemic attack (TIA) from a population-based cohort based in one general practice in each of 24 British towns.

RESULTS

In 1999, most men with cerebrovascular disease received antiplatelet drugs (67%). However, a few received blood pressure-lowering drugs (50%) and statins (13%). By 2005, the use of all drug types had increased; at least half of the patients received each type of drug. However, only one-third of patients received all three medication types and combined blood pressure treatment was limited. Older age, a diagnosis of TIA rather than stroke and absence of co-existing coronary heart disease were associated with lower rates of use of specific medication categories.

CONCLUSION

Despite improvements in secondary prevention medication use, there is scope for achieving the full potential of these medications, particularly by increasing combination blood pressure treatment and statin use and ensuring that older patients receive the benefits of prevention.

Inter-relationships of interleukin-6, cardiovascular risk factors and the metabolic syndrome among older men

OBJECTIVES

Interleukin-6 (IL-6) has been implicated in the development of cardiovascular disease. We have examined the relationship between plasma IL-6 and insulin resistance, and metabolic, inflammatory and hemostatic markers.

METHODS

We examined 3490 men aged 60-79 years who were drawn from general practices in 24 British towns. The men were not diabetic and were not taking warfarin.

RESULTS

IL-6 was significantly associated with age, body mass index (BMI), waist circumference (WC), cigarette smoking, low physical activity, social class and alcohol intake (U-shaped). IL-6 showed no association with insulin resistance or its other components (blood glucose, triglycerides, blood pressure) except high-density lipoprotein-cholesterol (inversely), and no association with hematocrit, factor (F) VII or adiponectin after adjustment for age and WC. IL-6 was strongly associated with markers of inflammation (C-reactive protein, fibrinogen, white cell count); plasma viscosity; elevated markers of coagulation (fibrin D-dimer, FVIII, FIX); markers of endothelial dysfunction (von Willebrand factor, tissue plasminogen activator); and to a smaller extent with platelet count, APC ratio and gamma glutamyltransferase. Risk of the metabolic syndrome increased significantly with increasing IL-6 but was attenuated after adjustment for BMI.

CONCLUSION

IL-6 may have a potential role as a mediator between cardiovascular risk factors and several biological mechanisms for cardiovascular disease.

Are childhood socio-economic circumstances related to coronary heart disease risk? Findings from a population-based study of older men

BACKGROUND

The independent influence of childhood social circumstances on health in later life remains uncertain. We examined the extent to which childhood socio-economic circumstances are related to the risk of coronary heart disease (CHD) in older British men, taking account of adult social class and behavioural risk factors.

METHODS

A socio-economically representative sample of 5552 British men (52-74 years) with retrospective assessment of childhood socio-economic circumstances (father's occupation and childhood household amenities) who were followed up for CHD (fatal and non-fatal) for 12 years.

RESULTS

Men whose childhood social class was manual had an increased hazard ratio (HR) 1.34 (95% CI 1.11-1.63)-this effect was diminished when adjusted for adult social class and adult behavioural risk factors (cigarette smoking, alcohol, physical activity and body weight) (HR 1.19; 95% CI 0.97-1.46). Men whose family did not own a car in their childhood were at increased CHD risk even after adjustments for adult social class and behaviours (HR 1.35, 95% CI 1.04-1.75). Men with combined exposure to both childhood and adult manual social class had the highest risk of CHD (HR 1.51; 95% CI 1.19-1.91); this was substantially reduced by adjustment for adult behavioural risk factors (adjusted HR 1.28; 95% CI 0.99-1.65).

CONCLUSIONS

Less affluent socio-economic conditions in childhood may have a modest persisting influence on risk of CHD in later life.

Adipokines and risk of type 2 diabetes in older men

OBJECTIVE

The aim was to assess the relationship between adipokines, including interleukin (IL)-6, leptin, and adiponectin, with development of type 2 diabetes and assess the role of obesity and insulin resistance in these relationships.

RESEARCH DESIGN AND METHODS

We conducted a prospective study of 3,599 nondiabetic men aged 60-79 years and followed up for a mean period of 5 years, during which time there were 108 incident cases of type 2 diabetes.

RESULTS

Elevated IL-6, leptin, and low adiponectin were associated with increased risk of type 2 diabetes even after adjustment for BMI, lifestyle factors, preexisting cardiovascular disease, and systolic blood pressure. The relative risks (RRs) (top vs. bottom third) were 2.02 (95% CI 1.14-3.58) for IL-6, 1.91 (0.97-3.76) for leptin, and 0.40 (0.23-0.70) for adiponectin. Further adjustment for insulin resistance made minor differences to the IL-6 diabetes relationship (adjusted RR 2.12 [1.18-3.81]), weakened the associations with adiponectin (0.59 [0.33-1.04]), and abolished the association between leptin and diabetes (1.12 [0.55-2.26]). The inverse relation between low adiponectin and diabetes was significantly stronger in men who were obese (waist circumference > 102 cm or BMI > or = 30 kg/m2) (0.30 [0.11-0.79]) relative to leaner men (0.93 [0.44-1.96]) (test for interaction P = 0.04).

CONCLUSIONS

The association between leptin and incident diabetes is mediated by insulin resistance. By contrast, the positive association between IL-6 and diabetes appeared to be independent of obesity and insulin resistance. Finally, the association between low adiponectin and increased risk of diabetes appears to be significantly stronger in obese men than in leaner counterparts.

HAART and the heart: changes in coronary risk factors and implications for coronary risk in men starting antiretroviral therapy

OBJECTIVES

To estimate changes in coronary risk factors and their implications for coronary heart disease (CHD) rates in men starting highly active antiretroviral therapy (HAART).

METHODS

Men participating in the Swiss HIV Cohort Study with measurements of coronary risk factors both before and up to 3 years after starting HAART were identified. Fractional polynomial regression was used to graph associations between risk factors and time on HAART. Mean risk factor changes associated with starting HAART were estimated using multilevel models. A prognostic model was used to predict corresponding CHD rate ratios.

RESULTS

Of 556 eligible men, 259 (47%) started a nonnucleoside reverse transcriptase inhibitor (NNRTI) and 297 a protease inhibitor (PI) based regimen. Levels of most risk factors increased sharply during the first 3 months on HAART, then more slowly. Increases were greater with PI- than NNRTI-based HAART for total cholesterol (1.18 vs. 0.98 mmol L(-1)), systolic blood pressure (3.6 vs. 0 mmHg) and BMI (1.04 vs. 0.55 kg m(2)) but not HDL cholesterol (0.24 vs. 0.32 mmol L(-1)) or glucose (1.02 vs. 1.03 mmol L(-1)). Predicted CHD rate ratios were 1.40 (95% CI 1.13-1.75) and 1.17 (0.95-1.47) for PI- and NNRTI-based HAART respectively.

CONCLUSIONS

Coronary heart disease rates will increase in a majority of patients starting HAART: however the increases corresponding to typical changes in risk factors are relatively modest and could be offset by lifestyle changes.

Associations of adiponectin with metabolic and vascular risk parameters in the British Regional Heart Study reveal stronger links to insulin resistance-related than to coronory heart disease risk-related parameters

BACKGROUND AND AIM

Adiponectin is considered by many to be part of the 'common soil' linking type 2 diabetes and coronary heart disease (CHD). We examined the relationship between adiponectin and insulin resistance, metabolic, inflammatory and haemostatic risk factors and hepatic function.

METHODS AND RESULTS

The study was carried out in 3640 non-diabetic men aged 60-79 years drawn from general practices in 24 British towns and who were not on warfarin. Adiponectin was associated with waist circumference (inversely), alcohol intake (positively) and physical activity (nonlinearly); no association was seen with cigarette smoking, prevalent CHD or stroke. After adjustment for these factors, adiponectin was significantly inversely associated with insulin resistance, triglyceride, C-reactive protein (but not interleukin 6), tissue plasminogen activator and alanine aminotransferase and positively associated with high-density lipoprotein cholesterol (HDL-cholesterol) and Factor VIII, factors associated with diabetes. No association was seen with cholesterol, smoking, systolic blood pressure or coagulation factors. Risk of the metabolic syndrome decreased significantly with increasing adiponectin.

CONCLUSION

Adiponectin is inversely associated with factors strongly associated with the development of diabetes. Limited associations with the established major risk factors for CHD suggest adiponectin may be a stronger marker of risk for diabetes than for CHD.

Measures of Thrombosis and Fibrinolysis

Our recent understanding of acute coronary syndrome as an atherothrombotic process has led to research efforts in the development of markers of thrombosis and fibrinolysis for risk prediction in cardiovascular heart disease. Although American Heart Association/American College of Cardiology guidelines recommend fibrinogen as a category I risk factor and also suggest factor VII, plasminogen activator inhibitor-1, tissue-type plasminogen activator, and von Willebrand factor as other potentially clinically useful markers, these tests have not come into routine clinical use. Their development as predictors of risk may be hampered by inconsistent laboratory methodology, which causes difficulty in comparing result interpretation with published trial studies. This article presents the history of development for these tests, proper laboratory handling, the best trial data that present evidence of their accuracy, and current guidelines for clinical use.

Carboxyhaemoglobin levels and their determinants in older British men

Background

Although there has been concern about the levels of carbon monoxide exposure, particularly among older people, little is known about COHb levels and their determinants in the general population. We examined these issues in a study of older British men.

Methods

Cross-sectional study of 4252 men aged 60–79 years selected from one socially representative general practice in each of 24 British towns and who attended for examination between 1998 and 2000. Blood samples were measured for COHb and information on social, household and individual factors assessed by questionnaire. Analyses were based on 3603 men measured in or close to (< 10 miles) their place of residence.

Results

The COHb distribution was positively skewed. Geometric mean COHb level was 0.46% and the median 0.50%; 9.2% of men had a COHb level of 2.5% or more and 0.1% of subjects had a level of 7.5% or more. Factors which were independently related to mean COHb level included season (highest in autumn and winter), region (highest in Northern England), gas cooking (slight increase) and central heating (slight decrease) and active smoking, the strongest determinant. Mean COHb levels were more than ten times greater in men smoking more than 20 cigarettes a day (3.29%) compared with non-smokers (0.32%); almost all subjects with COHb levels of 2.5% and above were smokers (93%). Pipe and cigar smoking was associated with more modest increases in COHb level. Passive cigarette smoking exposure had no independent association with COHb after adjustment for other factors. Active smoking accounted for 41% of variance in COHb level and all factors together for 47%.

Conclusion

An appreciable proportion of men have COHb levels of 2.5% or more at which symptomatic effects may occur, though very high levels are uncommon. The results confirm that smoking (particularly cigarette smoking) is the dominant influence on COHb levels.

The Dutch Famine of 1944-1945: a pathophysiological model of long-term consequences of wasting disease

PURPOSE OF REVIEW

The tragic circumstances of the Dutch Hunger Winter of 1944-1945 created a unique opportunity to study the relation between exposure to prenatal famine and health in adult life. This review addresses the literature on the effects of maternal malnutrition during the different periods of gestation and childhood on health in adult life.

RECENT FINDINGS

Exposure to famine during gestation resulted in increases in impaired glucose tolerance, obesity, coronary heart disease, atherogenic lipid profile, hypertension, microalbuminuria, schizophrenia, antisocial personality and affective disorders. Exposure to famine during childhood resulted in changes in reproductive function, earlier menopause, changes in insulin-like growth factor-I and increases in breast cancer.

SUMMARY

Exposure to famine during gestation and childhood has life-long effects on health, and these effects vary depending on the timing of exposure as well as evolution of the recovery period.

Plasma leptin: associations with metabolic, inflammatory and haemostatic risk factors for cardiovascular disease

BACKGROUND AND AIM

Leptin, an adipocyte-derived protein, regulating food intake and metabolism has been implicated in the development of coronary heart disease. We have examined the relationship between leptin and vascular risk factors including insulin resistance, metabolic, inflammatory and haemostatic risk factors.

METHODS AND RESULTS

The study was carried out in 3640 non-diabetic men aged 60-79 years drawn from general practices in 24 British towns and who were not on warfarin. Leptin was strongly positively correlated with waist circumference (r=0.58; p<0.0001). Leptin concentrations decreased significantly with increasing physical activity and were lowered in cigarette smokers and elevated in men with pre-existing coronary heart disease and stroke; alcohol intake showed no association with leptin concentration. After adjustment for waist circumference and these lifestyle factors, increased leptin was independently associated with significant increases in insulin resistance, triglycerides, inflammatory markers (interleukin-6, C-reactive protein, fibrinogen, plasma viscosity), coagulation factor VIII, endothelial markers von Willebrand factor, tissue plasminogen activator, and fibrin D-dimer levels; and a decrease in HDL-cholesterol. No association was seen between leptin and blood pressure, total cholesterol, glucose or white cell count after adjusting for waist circumference. Further adjustment for insulin resistance abolished the relationships between leptin and triglycerides and HDL-cholesterol, weakened the associations with the haemostatic factors although they remained significant, but made minor differences to the associations with inflammatory markers.

CONCLUSION

Plasma leptin is associated with insulin resistance, inflammation and disturbances in haemostasis independent of waist circumference, suggesting possible pathways by which leptin may influence risk of cardiovascular disease.

Effects of older age on fibrin D-dimer, C-reactive protein, and other hemostatic and inflammatory variables in men aged 60-79 years

BACKGROUND

Previous studies have suggested that several hemostatic and inflammatory variables, which are risk predictors for arterial or venous thrombosis, increase with age. However, there is a lack of data from large population studies for reliable estimates of reference ranges.

OBJECTIVES

To establish reliable reference ranges of hemostatic and inflammatory variables for 5-year age groups in older men and their implications for pathogenesis and diagnosis.

PATIENTS AND METHODS

A total of 3861 men aged 60-79 years at the 20 years follow-up of the British Regional Heart Study.

RESULTS

Several variables increased with age. The greatest median increases between 60-64 and 75-79 years age groups were observed for fibrin D-dimer (91%) and C-reactive protein (CRP) (57%). Significant median increases were also observed for von Willebrand factor antigen (23%), tissue plasminogen activator antigen (11%), factor VIII (10%), and fibrinogen (8%). In contrast, levels of classical cardiovascular risk factors neither decreased nor increased substantially with age, with the exception of systolic blood pressure (median increase 10%).

CONCLUSIONS

The exponential increases in risk of arterial and venous thrombotic events in men between age 60 and 79 years (when most such events occur) may be related in part to increasing activation of blood coagulation, fibrinolysis, and inflammation; possibly related to the increasing inflammatory burden of both atherosclerotic and non-vascular disease. These increases also have implications for diagnosis of suspected acute venous thromboembolism (D-dimer), and recently proposed screening for prediction of coronary heart disease risk and detection of occult disease (CRP).

Alcohol use and health outcomes in the oldest old

Background

As the United States population ages, an unprecedented proportion of the population will be aged 70 and older. Knowledge of alcohol use and its consequences in this age group is not well known. In light of the disparate findings pointing to negative outcomes with excessive drinking yet also benefits of moderate drinking, the true risk of alcohol use in late life needs more investigation.

Methods

This study examined the correlates and 2-year health outcomes related to alcohol use in 7,434 elders aged 70 years or older. Data was collected as part of the Assets and Health Dynamics of the Oldest Old (AHEAD), a nationwide health and economic study of elders. Data from Wave 1 and Wave 2 of AHEAD are presented. Frequency and quantity of drinking was assessed by self-report as was health status, lifetime alcohol or psychiatric problems, presence of chronic illness, functional impairment, and depressive symptoms. Cognitive status was assessed using a brief measure.

Results

Approximately 44% of the sample reported any alcohol use in the past three months, with the majority of drinking less than daily. Daily drinking was associated with being Caucasian, married, in relatively good health, and having good affective and cognitive status. Drinking was not associated with negative health outcomes two years later and was protective against stroke and functional impairment. Decline in drinking between Wave 1 and Wave 2 was strongly associated with poor health.

Conclusion

This study offers no evidence of negative health outcomes for drinking moderately and confirms the U-shaped curve often found in studies of alcohol and health. Nonetheless, cessation of drinking was associated with poor health suggesting the health benefits of moderate drinking may result from selection of a healthy group of people capable of sustained moderate drinking. Public health recommendations for moderate drinking must take this phenomenon into account.

Associations of vitamin C status, fruit and vegetable intakes, and markers of inflammation and hemostasis

BACKGROUND

It has been suggested that a high dietary intake and high circulating concentrations of vitamin C may protect against ischemic heart disease.

OBJECTIVES

The objective was to examine the associations between dietary and plasma vitamin C concentrations, fruit and vegetable intakes, and markers of inflammation and hemostasis associated with cardiovascular disease in older men free of cardiovascular disease.

DESIGN

This cross-sectional study examined 3258 men aged 60-79 y with no physician diagnosis of myocardial infarction, stroke, or diabetes and who were drawn from general practices in 24 British towns. Fruit and vegetable intakes and dietary vitamin C were assessed by using a food-frequency questionnaire.

RESULTS

Plasma vitamin C, fruit intake, and dietary vitamin C intake were significantly and inversely associated with mean concentrations of C-reactive protein, an acute phase reactant, and tissue plasminogen activator (t-PA) antigen, a marker of endothelial dysfunction, even after adjustment for confounders. Vegetable intake was correlated significantly (inversely) only with t-PA. For plasma vitamin C (highest versus lowest quartile), the adjusted odds of elevated C-reactive protein and t-PA (highest tertile versus lowest tertile) were 0.56 (95% CI: 0.44, 0.71) and 0.79 (0.62, 1.00); for fruit intake, the corresponding odds ratios were 0.76 (0.60, 0.95) and 0.76 (0.61, 0.95). Plasma (but not dietary) vitamin C also showed inverse associations with both fibrinogen concentrations and blood viscosity. No associations were seen with von Willebrand factor or factor VIII.

CONCLUSION

The findings suggest that vitamin C has antiinflammatory effects and is associated with lower endothelial dysfunction in men with no history of cardiovascular disease or diabetes.

Exclusion and inclusion of nonwhite ethnic minority groups in 72 North American and European cardiovascular cohort studies

BACKGROUND

Cohort studies are recommended for understanding ethnic disparities in cardiovascular disease. Our objective was to review the process for identifying, including, and excluding ethnic minority populations in published cardiovascular cohort studies in Europe and North America.

METHODS AND FINDINGS

We found the literature using Medline (1966-2005), Embase (1980-2001), Cinahl, Web of Science, and citations from references; consultations with colleagues; Internet searches; and RB's personal files. A total of 72 studies were included, 39 starting after 1975. Decision-making on inclusion and exclusion of racial/ethnic groups, the conceptual basis of race/ethnicity, and methods of classification of racial/ethnic groups were rarely explicit. Few publications provided details on the racial/ethnic composition of the study setting or sample, and 39 gave no description. Several studies were located in small towns or in occupational settings, where ethnic minority populations are underrepresented. Studies on general populations usually had too few participants for analysis by race/ethnicity. Eight studies were explicitly on Caucasians/whites, and two excluded ethnic minority groups from the whole or part of the study on the basis of language or birthplace criteria. Ten studies were designed to compare white and nonwhite populations, while five studies focused on one nonwhite racial/ethnic group; all 15 of these were performed in the US.

CONCLUSIONS

There is a shortage of information from cardiovascular cohort studies on racial/ethnic minority populations, although this has recently changed in the US. There is, particularly in Europe, an inequity resulting from a lack of research data in nonwhite populations. Urgent action is now required in Europe to address this disparity.

Hepatic enzymes, the metabolic syndrome, and the risk of type 2 diabetes in older men

OBJECTIVE

We have examined the relationship between hepatic enzymes, the metabolic syndrome, insulin resistance, and type 2 diabetes and assessed the potential of hepatic enzyme measurements in determining diabetes risk.

RESEARCH DESIGN AND METHODS

We conducted a prospective study of 3,500 nondiabetic men aged 60-79 years who were followed-up for a mean period of 5 years and in whom there were 100 incident type 2 diabetes cases.

RESULTS

In cross-sectional analyses, alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT) were strongly associated with obesity, insulin resistance, and the metabolic syndrome. Prospectively, the risk of type 2 diabetes significantly increased with increasing levels of ALT and GGT even after adjustment for confounders including BMI (top versus bottom quarter ALT: relative risk 2.72 [95% CI 1.47-5.02]; GGT: 3.68 [1.68-8.04]). Additional adjustment for insulin resistance attenuated the effects, but the relationships with ALT and GGT remained significant (1.91 [1.01-3.60] and 2.69 [1.21-5.97], respectively). Further adjustment for inflammatory markers (C-reactive protein) made minor differences. Among high-risk subjects (obese men or those with the metabolic syndrome), elevated GGT and ALT enhanced the prediction of diabetes risk.

CONCLUSIONS

Elevated levels of ALT and GGT within the normal range are independent predictors of type 2 diabetes in older men and are useful additional measures in identifying those at high risk of diabetes.

Body fat distribution, body composition, and respiratory function in elderly men

BACKGROUND

Most population studies have reported weak or nonsignificant associations between body mass index (BMI; in kg/m2) and lung function.

OBJECTIVE

This study focused on the distinct effects of fat distribution and body composition on lung function and examined these relations in elderly men.

DESIGN

The study was a cross-sectional evaluation of 2744 men aged 60-79 y who were free of cardiovascular disease and cancer and were drawn from general practices in 24 British towns. Anthropometric and body-composition [including fat mass (FM), fat-free mass (FFM), and percentage body fat (%BF) evaluated with bioelectric impedance] measurements were made, and lung function was examined by using spirometry.

RESULTS

Height-standardized forced expiratory volume in 1 s (FEV1) was diminished only in lean (BMI < 22.5) and obese (BMI > or = 30) men, but forced vital capacity (FVC) tended to decrease with increasing BMI (P < 0.01). All other measures of adiposity [ie, waist circumference (WC), waist-hip ratio (WHR), FM, and %BF] were significantly and inversely related to FEV1 and FVC after adjustment for confounders, including age and cigarette smoking (all: P < 0.05). This was seen both in nonobese (BMI < 30) and obese men. FFM was positively associated with FEV1 (P = 0.03) and to a lesser extent with FVC. Higher BMI and FFM were both associated with reduced odds of a low FEV1-FVC ratio (ie, <70%).

CONCLUSION

Total body fat and central adiposity are inversely associated with lung function, but increased FFM reflecting increases in muscle mass is associated with increased lung function and lower odds of low FEV1:FVC in the elderly.

Number needed to treat: A descriptor for weighing therapeutic options

PURPOSE

The utility and limitations of the number needed to treat (NNT) are described and compared with those of alternative descriptors of therapeutic yield.

SUMMARY

Pharmacists, physicians, and patients are more likely to launch interventions based on relative measures of therapeutic yield. The NNT is a simple way to express the absolute therapeutic yield of an intervention. It is essential to take baseline risk and length of follow-up into account when calculating and interpreting absolute or relative measures of therapeutic yield. Patients may have difficulty understanding what the NNT tells them about the benefits and harms associated with an intervention, and confidence intervals for the NNT can be difficult to interpret. Relative measures of benefits are advantageous for comparing benefits across populations with different risks. The use of absolute measures to describe therapeutic options leads to more conservative decision-making and is potentially more useful. Among the absolute measures, the absolute risk reduction may be easier to understand than the NNT. These measures are most helpful when the best options are not clear or when patient input is needed. Personal digital assistants and Web-based tools can assist with calculations.

CONCLUSION

The NNT is a useful measure but is influenced by numerous variables and may not be easily understood by patients.

From a postal questionnaire of older men, healthy lifestyle factors reduced the onset of and may have increased recovery from mobility limitation

BACKGROUND AND OBJECTIVE

We have examined predictors of the onset of and recovery from mobility limitation and the association between lifestyle changes in later life and mobility status.

STUDY DESIGN AND SETTING

From a cohort of 7,735 men recruited at ages 40-59 years (1978-1980), 5,075 men completed follow-up postal questionnaires in 1992 (Q92), then aged 52-73 years, and again in 1996 (Q96). Mobility limitation was defined as reported difficulty in any one or more of the following: getting outdoors, walking 400 yards, or climbing stairs.

RESULTS

Lifestyle factors (smoking, obesity, physical inactivity, and heavy drinking) and manual worker social class were significantly and independently associated with onset of mobility limitation and with the exception of physical activity remained significant after further adjustment for chronic diseases. Smoking cessation and taking up physical activity in later life are associated with reduced onset of mobility limitation. Among men with mobility limitation at Q92 (n=645), light or moderate levels of physical activity were associated with significantly increased odds of recovery at Q96 (light activity, OR=2.43, 95% CI 1.48, 4.00; moderate activity, OR=2.57, 95% CI 1.31, 5.02).

CONCLUSION

Maintaining and adopting a healthy lifestyle in later life reduces the onset of mobility limitation in old age. Maintaining physical activity may improve recovery.

Alcohol and adiposity: effects of quantity and type of drink and time relation with meals

BACKGROUND

It has been suggested that the effects of alcohol on body weight and fat distribution may be influenced by the quantity and type of drink and may differ according to whether the alcohol is consumed with meals or not.

OBJECTIVE

We have examined the cross-sectional association between alcohol intake, patterns of drinking and adiposity (body mass index (BMI), waist-to-hip ratio (WHR), waist circumference (WC) and percentage body fat (%BF)).

METHODS

We studied 3327 men aged 60-79 y with no history of myocardial infarction, stroke or diabetes drawn from general practices in 24 British towns.

RESULTS

BMI, WHR, WC and %BF increased significantly with increasing alcohol intake even after adjustment for potential confounders (all P < 0.0001), although the effects were stronger for WC and WHR (measures of central adiposity). Men who consumed > or = 21 units/week showed higher levels of central adiposity (WHR, WC) and general adiposity (BMI, %BF) than nondrinkers and lighter drinkers, irrespective of the predominant type of drink consumed (wine, beer, spirits or mixed). The positive association was most clearly seen in beer and spirit drinkers; positive but weaker associations were seen for wine. Among drinkers, a positive association was seen between alcohol intake and the adiposity variables irrespective of whether the alcohol was drunk with or separately from meals.

CONCLUSION

Higher alcohol consumption (> or = 21 units/week) is positively associated with general and to a greater extent with central adiposity, irrespective of the type of drink and whether the alcohol is drunk with meals or not.

The metabolic syndrome and insulin resistance: relationship to haemostatic and inflammatory markers in older non-diabetic men

AIMS

We have examined the cross-sectional relationship between insulin resistance, the metabolic syndrome and haemostatic and inflammatory markers.

METHODS AND RESULTS

We carried out the study in 2722 non-diabetic men aged 60-79 years with no history of coronary heart disease or stroke and who were not on warfarin treatment, drawn from general practices in 24 British towns. Insulin resistance (HOMA) was significantly associated with increased inflammatory markers (C-reactive protein (CRP), white cell count), coagulation factors VII-IX, von Willebrand factor (VWF) and tissue plasminogen activator (t-PA) antigens (markers of endothelial dysfunction) and blood viscosity after adjustment for age, smoking, physical activity, alcohol intake and waist circumference. Relationships with fibrinogen and fibrin D-dimer were weak. The relationship between HOMA and CRP was abolished after adjustment for t-PA. The prevalence of the metabolic syndrome was similar using World Health Organization (WHO) and National Cholesterol Education Program definitions (26.7% and 27.0%) but associations between the metabolic syndrome and increased haemostatic markers, particularly for raised factor VIII and VWF were stronger using WHO criteria.

CONCLUSION

Insulin resistance and the metabolic syndrome showed significant associations with markers of haemostasis and inflammation, which may be relevant to their associations with cardiovascular disease.

Correlation of regional cardiovascular disease mortality in India with lifestyle and nutritional factors

OBJECTIVE

There is a wide disparity in prevalence and cardiovascular disease mortality in different Indian states. To determine significance of various nutritional factors and other lifestyle variables in explaining this difference in cardiovascular disease mortality we performed an analysis.

METHODS AND RESULTS

Mortality data were obtained from the Registrar General of India. In 1998 the annual death rate for India was 840/100,000 population. Cardiovascular diseases contribute to 27% of these deaths and its crude mortality rate was 227/100,000. Major differences in cardiovascular disease mortality rates in different Indian states were reported varying from 75-100 in sub-Himalayan states of Nagaland, Meghalaya, Himachal Pradesh and Sikkim to a high of 360-430 in Andhra Pradesh, Tamil Nadu, Punjab and Goa. Lifestyle data were obtained from national surveys conducted by the government of India. The second National Family Health Survey (26 states, 92,447 households, 301,984 adults) conducted in 1998-1999 reported on various demographic and lifestyle variables and India Nutrition Profile Study reported dietary intake of 177,841 adults (18 states, 75,229 men, 102,612 women). Cardiovascular disease mortality rates were correlated with smoking, literacy levels, prevalence of stunted growth at 3-years (as marker of fetal undernutrition), adult mean body mass index, prevalence of overweight and obesity, dietary consumption of calories, cereals and pulses, green leafy vegetables, roots, tubers and other vegetables, milk and milk products, fats and oils, and sugar and jaggery. As a major confounder in different states is poverty, all the partial correlation coefficients were adjusted for illiteracy, fertility rate and infant mortality rate. There was a significant positive correlation of cardiovascular disease mortality with prevalence of obesity (R=0.37) and dietary consumption of fats (R=0.67), milk and its products (R=0.27) and sugars (R=0.51) and negative correlation with green leafy vegetable intake (R=-0.42) (p<0.05).

CONCLUSIONS

There are large disparities in cardiovascular disease mortality in different Indian states. This can be epidemiologically explained by difference in dietary consumption of fats, milk, sugar and green-leafy vegetables and prevalence of obesity.

Prevalence of undiagnosed Type 2 diabetes and impaired fasting glucose in older British men and women

AIM

To estimate the prevalence of undiagnosed diabetes and impaired fasting glucose in older British men and women, using the 1999 World Health Organization (WHO) thresholds based on fasting glucose measurements.

METHODS

Participants in the British Regional Heart Study and the British Women's Heart and Health Study were selected from one socially representative general practice in 24 British towns. Included in this analysis were 3736 men and 3642 women aged 60-79 years (predominantly white), who provided a single fasting blood sample at a clinical examination between 1998 and 2001, and who had no previous diagnosis of diabetes.

RESULTS

Two hundred and eleven men (5.7%) and 190 women (5.2%) had a fasting blood glucose level consistent with the WHO threshold for a diagnosis of diabetes (> or = 7.0 mmol/l), whilst a further 667 men (17.9%) and 642 women (17.6%) had impaired fasting glucose levels (6.1 < or = 7 mmol/l). When analyses were restricted to subjects who had fasted for at least 8 h, and whose blood sample was taken before 12.00 h, the predicted prevalence of undiagnosed diabetes (based on two separate measurements) was 6.7% in men and 6.0% in women. The predicted prevalence of impaired fasting glucose (based on two separate measurements) was approximately 20% in both sexes.

CONCLUSIONS

More than one-fifth of older white British men and women have either undiagnosed diabetes or impaired fasting glucose according to new WHO criteria. Strategies for the primary and secondary prevention of Type 2 diabetes among older individuals are urgently needed.

Measures of adiposity in the identification of metabolic abnormalities in elderly men

BACKGROUND

Body mass index (BMI; in kg/m(2)) is considered a poor indicator of overall and abdominal obesity in the elderly.

OBJECTIVES

Our goal was to determine which simple anthropometric measurements [BMI, waist-to-hip ratio (WHR), waist circumference (WC), percentage body fat (%BF), or fat mass (FM)] are most closely associated with metabolic risk factors and insulin resistance in elderly men.

DESIGN

This was a cross-sectional study of 2924 men aged 60-79 y with no history of coronary heart disease, stroke, or diabetes who were drawn from general practices in 24 British towns.

RESULTS

BMI and WC were the measures most strongly associated with the metabolic syndrome (>/=3 of the following: hypertension, low HDL cholesterol, high triacylglycerols, or high blood glucose) and insulin resistance. For a 1-SD increase in BMI, WC, WHR, %BF, and FM, the odds ratios (95% CIs) of having the metabolic syndrome after adjustment for age, socioeconomic status, smoking status, and physical activity were as follows: BMI, 1.61 (1.44, 1.79); WC, 1.65 (1.48, 1.81); WHR, 1.49 (1.34, 1.66); %BF, 1.41 (1.25, 1.59); and FM, 1.53 (1.38, 1.70). For insulin resistance, the odds ratios (95% CIs) were as follows: 2.48 (2.22, 2.77), 2.46 (2.19, 2.65), 1.75 (1.59, 1.93), 1.79 (1.60, 2.00), and 2.10 (1.88, 2.34), respectively. In normal-weight (BMI < 25) and overweight (BMI 25-29.9) men, the presence of the metabolic syndrome and insulin resistance increased with increasing WC; this did not occur in obese men.

CONCLUSIONS

BMI and WC are the simple measures of adiposity most strongly associated with metabolic abnormalities in elderly men. Our findings suggest that WC can be used as a complementary measurement to identify health risks in normal-weight and overweight elderly persons.

Inequalities in coronary revascularisation during the 1990s: evidence from the British regional heart study

OBJECTIVE

To investigate the influence of age and social circumstances on probability of revascularisation among British men.

DESIGN

Prospective population based study

SETTING

24 medium sized British towns, none of which contained a hospital undertaking coronary artery bypass surgery.

SUBJECTS

5814 surviving participants of the BRHS (British regional heart study), aged 52-73 years, with no history of revascularisation when responding to a questionnaire in November 1992.

MAIN OUTCOMES

Incident coronary revascularisations, as documented in general practitioner records, over the following 7.1 years and coronary angiography investigations reported by men in a further questionnaire in November 1996.

RESULTS

160 men underwent at least one revascularisation during this period (4.2/1000 person-years). In multifactorial analysis, which included adjustment for incidence of major coronary heart disease or angina, a lower incidence of revascularisation was found among men aged over 65 years in November 1992 (hazard ratio 0.62, 95% confidence interval (CI) 0.44 to 0.87), among men with manual occupations (0.73, 95% CI 0.53 to 1.02), among men living in households possessing no car (0.44, 95% CI 0.24 to 0.80) or one car (0.60, 95% CI 0.42 to 0.87) compared with two or more cars, among council tenants (0.49, 95% CI 0.25 to 0.97), and among men living outside southern England (0.71, 95% CI 0.51 to 0.99). Only car ownership was related to the incidence of diagnostic angiography: the odds ratio for angiography for those owning fewer than two cars was 0.62 (95% CI 0.42 to 0.89).

CONCLUSION

During the 1990s, there were major inequalities in the probability of undergoing coronary revascularisation between British men according to socioeconomic status, age, and geographic location.

Overweight and obesity and weight change in middle aged men: impact on cardiovascular disease and diabetes

CONTEXT

The benefit of weight reduction for cardiovascular disease (CVD) outcomes remains uncertain.

OBJECTIVE

To examine the effects of baseline body mass index on major CVD outcomes and diabetes over a 20 year follow up, and of weight change in the first five years over the subsequent 15 years.

DESIGN AND SETTING

A prospective study of British men followed up for 20 years.

PARTICIPANTS

Men aged 40-59 years with no diagnosis of CVD or diabetes (n = 7176) of whom 6798 provided full information on weight change five years later.

OUTCOME MEASURES

Major CVD events (fatal and non-fatal myocardial infarction and stroke, angina, "other" CVD deaths) and diabetes.

RESULTS

During the 20 year follow up there were 1989 major CVD events and 449 incident cases of diabetes in the 7176 men. Risk of major CVD and diabetes increased significantly with increasing overweight and obesity. During the 15 year follow up, weight gain was associated with increased risk of CVD and diabetes. Weight loss was associated with lower risk of diabetes than the stable group irrespective of initial weight. No significant cardiovascular benefit was seen for weight loss in any men, except possibly in considerably overweight (BMI 27.5-29.9 kg/m(2)) younger middle aged men (RR = 0.42; 95% CI 0.22 to 0.81).

CONCLUSION

Long term risk of CVD and diabetes increased significantly with increasing overweight and obesity. Weight loss was associated with significant reduction in risk of diabetes but not CVD, except possibly in considerably overweight younger men. Duration and severity of obesity seem to limit the cardiovascular benefits of weight reduction in older men.

Trends in rates of different forms of diagnosed coronary heart disease, 1978 to 2000: prospective, population based study of British men

OBJECTIVE

To examine trends over time in rates of different forms of diagnosed coronary heart disease among British men, during a period in which mortality due to coronary heart disease has been declining.

DESIGN

Prospective cohort study covering the period 1978-80 to 1998-2000.

PARTICIPANTS

7735 men, aged 40-59 at entry, randomly selected from one general practice in each of 24 British towns.

MAIN OUTCOME MEASURES

Trends in the rates of major coronary events, first diagnosed angina and first diagnosed coronary heart disease (any fatal or non-fatal documented event or diagnosis). Events were ascertained from NHS central registers and reviews of medical records from general practices.

RESULTS

Over the 20 year period, 1561 major coronary events occurred; 1087 and 1816 men had new diagnoses of angina and coronary heart disease, respectively. The age adjusted annual relative changes were -3.6% (95% confidence interval -4.8% to -2.4%, P < 0.001) for all major coronary events, 2.6% (1.1% to 4.0%, P < 0.001) for first diagnosed angina and -0.8% (-1.8% to 0.3%, P = 0.18) for first diagnosed coronary heart disease. The fall in major coronary events occurred across all categories of event (fatal and non-fatal, first and recurrent). Similarly, first diagnosed angina increased for both uncomplicated angina and angina after myocardial infarction. The age adjusted annual relative change in case fatality at 28 days of first major coronary events was -1.4% (-3.1% to 0.4%, P = 0.12).

CONCLUSIONS

Among British middle aged men, a substantial decline in the rate of major coronary events over the past two decades seems to have been largely offset by an increase in the incidence of diagnosed angina. Overall there was little change in the incidence of first diagnosed coronary heart disease. A continuing need exists for resources and services for coronary heart disease in general, and for new angina in particular.

Alcohol intake in middle age and risk of cardiovascular disease and mortality: accounting for intake variation over time

Moderate alcohol consumption is associated with a decreased risk of cardiovascular disease. However, the impact of variation in alcohol intake over time on estimated risk relations has not been adequately addressed. In this study, 6,544 middle-aged British men without previous cardiovascular disease were followed for cardiovascular events and all-cause mortality over 20 years from 1978/1980 to 1998/2000. Alcohol intake was ascertained at regular points throughout the study. A total of 922 men had a major coronary event within 20 years, 352 men had a stroke, and 1,552 men died of all causes. Baseline alcohol intake displayed U-shaped relations with cardiovascular disease and all-cause mortality, with light drinkers having the lowest risks and nondrinkers and heavy drinkers having similarly high risks. However, the nature of these relations changed after adjustment for intake variation; risks associated with nondrinking were lowered, and risks associated with moderate and heavy drinking increased. Regular heavy drinkers had a 74% higher risk of a major coronary event, a 133% higher risk of stroke, and a 127% higher risk of all-cause mortality than did occasional drinkers (these estimates were 8%, 54%, and 44% before adjustment for intake variation). The findings suggest that considerable caution may be needed before any recommendations regarding acceptable limits of alcohol consumption are made.

Intraclass correlation coefficient and outcome prevalence are associated in clustered binary data

BACKGROUND AND OBJECTIVE

To describe the association between values for a proportion and the intraclass correlation coefficient (ICC).

METHODS

Analysis of data obtained from the General Practice Research Database (GPRD) for variation between United Kingdom general practices and results from a Health Technology Assessment (HTA) review for a range of outcomes in community and health services settings.

RESULTS

There were 188 ICCs from the GPRD, the median prevalence was 13.1% (interquartile range IQR 3.5 to 28.4%) and median ICC 0.051 (IQR 0.011 to 0.094). There were 136 ICCs from the HTA review, with median prevalence 6.5% (IQR 0.4 to 20.7%) and median ICC 0.006 (IQR 0.0003 to 0.036). There was a linear association of log ICC with log prevalence in both datasets (GPRD, regression coefficient 0.61, 95% confidence interval 0.53 to 0.69, P < 0.001; HTA, 0.91, 0.81 to 1.01, P < 0.001). When the prevalence was 1% the predicted ICC was 0.008 from the GPRD or 0.002 from the HTA, but when the prevalence was 40% the predicted ICC was 0.075 (GPRD) or 0.046 (HTA).

CONCLUSION

The prevalence of an outcome may be used to make an informed assumption about the magnitude of the intraclass correlation coefficient.

Lifestyle and cardiovascular disease in middle-aged British men: the effect of adjusting for within-person variation

AIMS

To examine the effect that within-person variation has on the estimated risk associations between cigarette smoking, physical inactivity, and increased body mass index (BMI) and the development of cardiovascular disease (CVD) in middle-aged British men.

METHODS AND RESULTS

In total, 6452 men aged 40-59 with no prior evidence of CVD were followed for major CVD events (fatal/non-fatal myocardial infarction or stroke) and all-cause mortality over 20 years; lifestyle characteristics were ascertained at regular points throughout the study. A major CVD event within the first 20 years was observed in 1194 men (18.5%). Use of baseline assessments of cigarette smoking and physical activity in analyses resulted in underestimation of the associations between average cumulative exposure to these factors and major CVD risk. After correction for within-person variation, major CVD rates were over four times higher for heavy smokers (> or =40 cigarettes/day) compared with never smokers and three times higher for physically inactive men compared with moderately active men. Major CVD risk increased by 6% for each 1 kg/m(2) increase in usual BMI. If all men had experienced the risk levels of the men who had never regularly smoked cigarettes, were moderately active, and had a BMI of < or =25 kg/m(2) (6% of the population), 66% of the observed major CVD events would have been prevented or postponed (63% before adjustment for within-person variation). Adjustment for a range of other risk factors had little effect on the results. Similar results were obtained for all-cause mortality.

CONCLUSION

Failure to take account of within-person variation can lead to underestimation of the importance of lifestyle characteristics in determining CVD risk. Primary prevention through lifestyle modification has a great preventive potential.

Associations between cigarette smoking, pipe/cigar smoking, and smoking cessation, and haemostatic and inflammatory markers for cardiovascular disease

AIMS

To examine the associations between cigarette smoking, pipe/cigar smoking, and years since quitting smoking, and inflammatory and haemostatic markers.

METHODS AND RESULTS

A study in 2920 men aged 60-79 with no history of myocardial infarction, angina, stroke, or diabetes, and who were not on warfarin, from general practices in 24 British towns. After adjustment for other major cardiovascular risk factors, compared with never smokers, current cigarette smokers showed significantly higher levels of C-reactive protein (2.53 vs. 1.35 mg/L), white cell count (7.92 vs. 6.42 x 10(9)/L), and fibrinogen (3.51 vs. 3.13 g/L). They also showed higher levels of haematocrit, blood and plasma viscosity, tissue plasminogen activator antigen, and fibrin D-dimer, and lower levels of albumin. Primary pipe/cigar smokers showed levels similar to never smokers. Ex-cigarette smokers and secondary pipe/cigar smokers showed intermediate levels although secondary pipe/cigar smokers showed higher odds of having elevated white cell count and fibrinogen than ex-cigarette smokers. Most inflammatory and haemostatic levels improved within 5 years of smoking cessation but took over 20 years to revert to levels of never smokers.

CONCLUSION

These findings suggest that activation of inflammation and haemostasis may be potential mechanisms by which cigarette and pipe/cigar smoking increase cardiovascular risk.

Coronary heart disease prevention in clinical practice: are patients with diabetes special? Evidence from two studies of older men and women

OBJECTIVE

To assess whether the extent of primary and secondary coronary heart disease (CHD) prevention in older British men and women differs between patients with and without diabetes.

DESIGN

Two prospective cardiovascular cohort studies.

SETTING

24 British towns.

PATIENTS

4252 men and 4286 women aged 60-79 years examined between 1998 and 2001.

MAIN OUTCOME MEASURES

Use of aspirin, statin, and blood pressure lowering treatment and risk factor control, examined by diabetic status and history of established CHD.

RESULTS

About 20% of the men and 12% of the women had established CHD at age 60-79 years and 7% of the men and 5% of the women had diabetes. In primary CHD prevention, patients with diabetes were more likely to receive CHD risk reducing medications than those without diabetes, but the proportions receiving preventive treatments in both groups were low. In secondary prevention, diabetic and non-diabetic patients received similar levels of treatment, with the exception of angiotensin converting enzyme inhibitors and (for women only) blood pressure lowering treatment, which were more widely used among diabetic patients. There were no clear differences in blood pressure control or cigarette smoking by diabetic status in primary or secondary prevention. Mean total cholesterol concentrations were lower in diabetic patients independently of treatment with statins.

CONCLUSIONS

Despite their exceptionally high CHD risk, many opportunities to reduce CHD risk among patients with diabetes have not been taken.

Cardiovascular disease incidence and mortality in older men with diabetes and in men with coronary heart disease

OBJECTIVE

To examine the relation of diabetes and coronary heart disease (CHD; myocardial infarction (MI) or angina) to the incidence of major CHD and stroke events and total mortality.

METHODS

Prospective study of 5934 men aged 52-74 years followed up for 10 years. The men were divided into five groups according to their diabetes and CHD status.

RESULTS

During the follow up there were 662 major CHD events, 305 major stroke events, and 1357 deaths from all causes (637 cardiovascular disease (CVD) deaths, 417 CHD deaths). Men with diabetes had significantly increased cardiovascular and total mortality risk compared with non-diabetic men with no CHD but lower risk than men with prior MI only. The adjusted relative risk for CHD deaths was 2.82 (95% confidence interval (CI) 1.85 to 4.28) in men with diabetes only, 2.12 (95% CI 1.53 to 2.93) in men with angina only, 3.91 (95% CI 3.07 to 4.99) in men with MI, and 8.93 (95% CI 6.13 to 12.99) in men with both diabetes and CHD. Case fatality among men with diabetes only was similar to those with prior MI only. CHD and CVD mortality increased with increasing duration of diabetes with risk eventually approaching that of patients with MI without diabetes.

CONCLUSION

Men with diabetes only have a CVD risk intermediate between men with angina and men with prior MI. Their absolute risk is high and the prognosis for diabetic patients who develop CHD is extremely poor.

Social inequalities and disability in older men: prospective findings from the British regional heart study

The independent association of socio-economic position with self-reported disability was assessed. The effect of home and car ownership as additional indices of socio-economic position within occupational social classes was explored. Data from a prospective study of a cohort of 7735 men aged 40-59 years at recruitment and representative of the occupational social class distribution of middle-aged men in Great Britain were used. Men were selected from one general practice in each of 24 towns in England, Wales and Scotland in 1978-1980. The present study concerns 5773 (88.4% of those able to take part) men aged 52-73 years at follow up in 1992 who completed the disability section of a postal questionnaire. A quarter (1453) of men reported disability. Socio-economic position measured as both occupational class (social class I vs. V: age-adjusted OR 5.0, 95% CI 3.4-7.5) and ownership of home and car (both vs. neither: age-adjusted OR 2.8, 95% CI 2.3-3.4) showed a graded relationship with likelihood of reporting disability in 1992. Within all social class groups, those owning both home and car had a lower risk of disability than those who owned neither, even after adjustment for a wide range of risk factors. Men from manual occupations were more likely than those in non-manual occupations to report disability on developing chronic diseases. The relationship between socio-economic position and severe, but not milder, disability appeared to be independent of disease status. Socio-economic position is a strong predictor of disability in later life independent of a wide range of lifestyle factors and presence of diagnosed disease. The likelihood of reporting disability between and within social class groups is influenced by material wealth.

Sex differences in body fat distribution and carotid intima media thickness: cross sectional survey using data from the British regional heart study

OBJECTIVE

To determine the role of central adiposity in explaining sex differences in carotid intima media thickness (IMT).

DESIGN

Cross sectional survey.

SETTING

Two British towns.

PARTICIPANTS

800 men and women aged 56-75 years.

MAIN OUTCOME MEASURES

Carotid IMT.

RESULTS

There was a continuous linear association between waist-hip ratio and IMT in both men and women. The magnitude of the association between waist to hip ratio and IMT was identical in both sexes. In age adjusted analyses IMT was 14% greater in men compared with women (age adjusted male to female ratio of geometric means 1.14; 95% confidence interval 1.07 to 1.21) with adjustment for waist to hip ratio this attenuated to no difference (1.00; 0.92 to 1.09). Adjustment for body mass index and for lifestyle risk factors had very little effect on the sex difference in mean intima media thickness.

CONCLUSIONS

Sex differences in body fat distribution may explain sex differences in arterial atherosclerosis.

Insulin resistance, haemostatic and inflammatory markers and coronary heart disease risk factors in Type 2 diabetic men with and without coronary heart disease

AIMS/HYPOTHESIS

We have examined markers of haemostasis and inflammation in men with diabetes, coronary heart disease (CHD) or both, and assessed their associations with insulin resistance in men with Type 2 diabetes.

METHODS

The study was carried out in 4066 British men aged 60 to 79 years who were not on warfarin or insulin, of whom there were 426 men with prevalent Type 2 diabetes and 842 with prevalent CHD.

RESULTS

Men with Type 2 diabetes were more likely to have multiple risk factors and higher levels of haemostatic and inflammatory markers than men without, irrespective of CHD status. Compared with men with CHD only, men with diabetes only showed increased levels of tissue plasminogen activator antigen, increased plasma and blood viscosity, and increased levels of coagulation factors VII, VIII and IX. They also had dyslipidaemia. In men with diabetes, increased insulin resistance (homeostasis model assessment, HOMA) was associated with increased levels of haemostatic markers and dyslipidaemia. The prevalence of CHD increased significantly with increasing tertiles of HOMA (adjusted odds ratio 1.32 [95% CI: 0.72-2.42] in the second, and 1.70 [95% CI: 0.92-3.44] in the third tertile; p=0.04 for trend).

CONCLUSIONS/INTERPRETATION

Increased insulin resistance among men with Type 2 diabetes is associated with increased prevalence of CHD and of activated haemostasis and dyslipidaemia. Reducing insulin resistance in men with diabetes may reduce their tendency to develop thrombosis and hence CHD risk.

Overweight and obesity and the burden of disease and disability in elderly men

OBJECTIVE

To examine the prevalence of disease burden and disability associated with overweight and obesity in men aged 60-79 y and to assess whether the current WHO weight guidelines are appropriate in the elderly.

DESIGN

Cross-sectional survey 20 y after enrollment.

SETTING

General practices in 24 British towns.

PARTICIPANTS

In total, 4232 men aged 60-79 y (77% of survivors) with measured weight and height.

MAIN OUTCOME MEASURES

Cardiovascular (CV) risk factors, prevalence of diabetes, cardiovascular disease, cancer, disability and regular medication.

RESULTS

In total, 17% of the men were obese (body mass index (BMI) >/=30 kg/m(2)) and a further 52% were overweight (BMI 25-29.9 kg/m(2)). Prevalence of hypertension, low HDL-cholesterol, high triglycerides and insulin resistance and the prevalence of most disease outcomes increased with increasing degrees of overweight/obesity. Men in the normal weight range (18.5-24.9 kg/m(2)) had the lowest prevalence of ill health. Compared with normal weight men, obese men showed a two-fold risk of major CVD (odds ratio (OR)=1.96, 95% CI 1.44-2.67) and locomotor disability (OR=2.26, 95% CI 1.66, 3.09) and were nearly three times as likely to have diabetes, CV interventions or to be on CV medication. Over 60% of the prevalence of high insulin resistance was attributable to overweight and obesity as was over a third of diabetes and hypertension, a quarter of locomotor disability and a fifth of major CVD.

CONCLUSION

In elderly men, overweight and obesity are associated with a significantly increased burden of disease, in particular CV-related disorders and disability. The current guidelines for overweight and obesity appear to be appropriate in elderly men.

Clustering of risk factors and social class in childhood and adulthood in British women's heart and health study: cross sectional analysis

OBJECTIVE

To examine co-occurrence and clustering of risk factors used in the Framingham equation by social class in childhood and adult life.

DESIGN

Cross sectional study.

SETTING

23 towns across England, Wales, and Scotland.

PARTICIPANTS

2936 women aged 60-79 years.

MAIN OUTCOME MEASURES

Prevalence of risk factors (hypertension, obesity, smoking, left ventricular hypertrophy on electrocardiography, diabetes, and low concentration of high density cholesterol); ratios of observed to expected frequencies of clusters of risk factors.

RESULTS

Risk factors were more common in women from manual social classes in either childhood or adult life, and the co-occurrence of three or four of these risk factors was greater among more disadvantaged groups. Within the four socioeconomic groups, these risk factors occurred together more than would be expected from their individual frequency distributions, indicating that they were clustered. The extent of this clustering was similar in all four social class groups.

CONCLUSIONS

Clustering of risk factors included in the Framingham risk function occurs in all social class groups, but the lack of social patterning makes it unlikely that clustering is an explanation of socioeconomic inequalities in cardiovascular disease. As the proportion of women with co-occurrence of risk factors is greatest in those from manual social class in childhood, this measure of socioeconomic position might prove useful in risk prediction.

Genetic risk factors for stroke and carotid atherosclerosis: insights into pathophysiology from candidate gene approaches

Ischaemic stroke is the most common form of stroke and is caused by atherosclerosis in most patients. Several genetic determinants contribute to stroke risk. Of these, carotid intimal-medial wall thickness (IMT) is particularly relevant, because it is a surrogate measure of subclinical atherosclerosis and a strong predictor of future ischaemic stroke. Studies of twins, siblings, and families have provided significant evidence for heritability, but the genes involved have not been identified. Some researchers have reported that IMT is high in people with functional variants of genes related to matrix deposition (MMP3), inflammation (interleukin 6), and lipid metabolism (hepatic lipase, APOE, CETP, and PON1). In this review, we assess the robustness of these associations and examine whether there is any evidence of risk modification by factors, such as smoking.

Serum albumin and risk of stroke, coronary heart disease, and mortality: the role of cigarette smoking

OBJECTIVE

Lower levels of serum albumin are associated with increased risk of all-cause and cardiovascular mortality as well as with coronary heart disease and stroke incidence. These relationships have been examined with specific focus on the role of cigarette smoking.

STUDY DESIGN AND SETTING

A prospective study of 7,690 British men aged 40-59 years, with 16.8 years mean follow-up.

RESULTS

Cigarette smoking was strongly and inversely associated with serum albumin concentrations that reverted to levels seen in never smokers after 5 years' cessation. Only in current and former smokers were there significant inverse relationships between serum albumin and risk of major CHD and stroke events even after adjustment for potential confounders. Only in current smokers was a significant inverse relationship seen between serum albumin and mortality from cardiovascular disease, cancer, and all causes.

CONCLUSION

The inverse association between serum albumin concentration and disease outcome appears to be related to the effects of cigarette smoking on serum albumin concentration.

Birthweight of offspring and paternal insulin resistance and paternal diabetes in late adulthood: cross sectional survey

AIMS/HYPOTHESIS

It has been proposed that genetic factors involved in insulin action could explain part of the link between low birthweight and risk of cardiovascular disease and diabetes in adulthood. To confirm this we examined the association between offspring birthweight and paternal insulin resistance and diabetes in late adulthood.

METHODS

We did a cross-sectional survey of 4252 men who were 60 to 79 years of age and from 24 British towns. Of these, 2788 men provided details of their offsprings' birthweight and sex.

RESULTS

Offspring birthweight was inversely associated with paternal insulin resistance defined by the homeostasis model assessment (HOMA) score and with Type 2 diabetes in late adulthood. Fathers of offspring in the highest quartile of sex-standardised birthweight SD scores had a 34% reduction in odds of having a high HOMA insulin resistance score (OR=0.66, 95% CI: 0.47 to 0.92) compared with fathers of offspring in the lowest quartile after adjustment for potential confounders. A stronger inverse association was seen between offspring birthweight and risk of paternal diabetes (adjusted OR=0.59, 95% CI: 0.39 to 0.88 top quartile vs lowest quartile). For each increase of offspring-birthweight SD score the odds of high HOMA scores decreased by 13% (OR=0.87, 95% CI: 0.78 to 0.98) and the odds for diabetes by 17% (OR=0.83, 95% CI: 0.72 to 0.95), after full adjustment.

CONCLUSIONS/INTERPRETATION

Offspring birthweight is inversely associated with paternal insulin resistance and diabetes in late adulthood, supporting the hypothesis that genetic factors related to insulin action contribute to the association between birthweight and adult cardiovascular disease and diabetes risk.

Pipe and cigar smoking and major cardiovascular events, cancer incidence and all-cause mortality in middle-aged British men

BACKGROUND

Pipe and cigar smoking are still regarded by many as less hazardous to health than cigarette smoking.

METHODS

Prospective study of 7735 men aged 40-59 years drawn from general practices in 24 British towns with mean follow-up of 21.8 years. The outcome measures include major coronary heart disease (CHD) and stroke events, cancer incidence, and deaths from all causes.

RESULTS

There were 1133 major CHD events and 440 stroke events, 919 new cancers and 1994 deaths from all causes in the 7121 men with no diagnosed CHD, stroke, diabetes, or cancer at screening. Compared with never smokers, pipe/cigar smokers (primary and secondary combined) showed significantly higher risk of major CHD events (relative risk [RR] = 1.69, 95% CI: 1.32, 2.14) and stroke events (RR = 1.62, 95% CI: 1.08, 2.41) and of cardiovascular, non-cardiovascular, and total mortality (RR = 1.49, 95% CI: 1.13, 1.96, RR = 1.40, 95% CI: 1.08, 1.83 and RR = 1.44, 95% CI: 1.19, 1.74, respectively), after adjustment for lifestyle and biological characteristics. They also showed a significantly higher incidence of smoking-related cancers (RR = 2.67, 95% CI: 1.70, 4.26), largely due to lung cancer (RR = 4.35, 95% CI: 2.05, 8.94). Overall, the effects in pipe/cigar smokers were intermediate between never-smokers and light cigarette smokers, although risks for lung cancer were similar to light cigarette smokers.

CONCLUSION

Pipe and cigar smoking, whether primary or secondary, carries significant risk of smoking-related ill health.

Predictive accuracy of the Framingham coronary risk score in British men: prospective cohort study

OBJECTIVE

To establish the predictive accuracy of the Framingham risk score for coronary heart disease in a representative British population.

DESIGN

Prospective cohort study.

SETTING

24 towns in the United Kingdom.

PARTICIPANTS

6643 British men aged 40-59 years and free from cardiovascular disease at entry into the British regional heart study.

MAIN OUTCOME MEASURES

Comparison of observed 10 year coronary heart disease mortality and event rates with predicted rates for each individual, using the relevant Framingham risk equation.

RESULTS

Of 6643 men, 2.8% (95% confidence interval 2.4% to 3.2%) died from coronary heart disease compared with 4.1% predicted (relative overestimation 47%, P < 0.0001). A fatal or non-fatal coronary heart disease event occurred in 10.2% (9.5% to 10.9%) of the men compared with 16.0% predicted (relative overestimation 57%, P < 0.0001). These relative degrees of overestimation were similar at all levels of coronary heart disease risk, so that overestimation of absolute risk was greatest for those at highest risk. A simple adjustment provided an improved level of accuracy. In a "high risk score" approach, most cases occur in the low risk group. In this case, 84% of the deaths from coronary heart disease and non-fatal events occurred in the 93% of men classified at low risk (< 30% in 10 years) by the Framingham score.

CONCLUSION

Guidelines for the primary prevention of coronary heart disease advocate offering preventive measures to individuals at high risk. Currently recommended risk scoring methods derived from the Framingham study significantly overestimate the absolute coronary risk assigned to individuals in the United Kingdom.