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D Bainton

Publications and source records attributed to D Bainton.

At least 19 recordsLinked to original sources

Is metabolic syndrome a discrete entity in the general population? Evidence from the Caerphilly and Speedwell population studies.

OBJECTIVE: To examine the clinical and epidemiological utility of the concepts of metabolic syndrome and insulin resistance syndrome in two prospective cohort studies of white men. METHODS: Men aged 45-63 years were screened for evidence of ischaemic heart disease (IHD) between 1979 and 1982 and followed up at regular intervals thereafter. Non-fatal coronary events were validated from hospital records and fatal coronary events from death certificates. RESULTS: Analysis of serum insulin concentrations in non-diabetic individuals measured at entry to the study showed no independent contribution to the prediction of subsequent IHD at 10 year follow up. Blood glucose concentrations, however, showed a small independent contribution in the combined cohort in the upper fifth of the distribution. Three different models of metabolic syndrome among non-diabetic individuals were defined based on tertiles, medians, and clusters. The predictive value of each model was assessed using logistic regression before and after adjustment for conventional and metabolic risk factors. After adjustment the odds were non-significant and close to unity. CONCLUSIONS: This study did not detect any complex relation among the five variables defining metabolic syndrome; the excess risk seems to be no greater than can be explained by individual effects of the defining variables in a multiple logistic model.

Blood Glucose↗

Does non-diabetic hyperglycemia predict future IHD? Evidence from the Caerphilly and Speedwell studies.

We have examined the risk of subsequent ischemic heart disease (IHD) in men according to their initial fasting plasma glucose level in a prospective cohort study (Caerphilly Collaborative Study) of 4860 middle aged men from South Wales and Bristol, U.K. Ninety-four men reported themselves to be diabetic at initial screening and fasting venous plasma glucose levels were determined in these men and in a further 4519 non-diabetic men. At follow-up new IHD events occurred twice as commonly in diabetics compared to non-diabetics and overall mortality was increased 4-fold. Among non-diabetics however, increased IHD events only occurred in men with fasting values at the upper end of the distribution of baseline plasma glucose values [at 6.8 mmol/l (122 mg/dl) or more]. This association was reduced, but remained statistically significant, after adjusting for factors associated with plasma glucose levels; body mass index, plasma triglyceride, smoking habit and pre-existing IHD. In conclusion there is no evidence of a consistent, graded increase in risk of IHD by initial fasting plasma glucose level although the risk is significantly increased in men with baseline plasma values at 6.8 mmol/l (122 mg/dl) or more, and also in diabetics. This study suggests that such levels probably represent a pre-diabetic state in many individuals. Appropriate non-pharmacological intervention may be useful in halting the progression to the diabetic state, although this should be tested in experimental studies.

Blood Glucose↗

Peripheral vascular disease: consequence for survival and association with risk factors in the Speedwell prospective heart disease study.

OBJECTIVE: To measure the prevalence and incidence of intermittent claudication, to describe the mortality associated wtih the condition, and to assess the relevance of risk factors for vascular disease. DESIGN: A standard questionnaire on calf pain when walking was given in the prospective Speedwell study, and a range of risk factors were measured. The men were re-examined at intervals of three years, and deaths over 11 years were identified. SETTING: The general population. PARTICIPANTS: All men aged 45 to 59 registered with 16 general practitioners. RESULTS: The prevalence of intermittent claudication increased from almost nil at ages 45-49 to 2.9% at ages 60-64. The annual incidence increased from 0.3% in the youngest men to 0.5% in those in their early 60s. Intermittent claudication was related to the existence of ischaemic heart disease, particularly angina, at the first examination. The relative odds of men with angina developing intermittent claudication was 6.7 (95% confidence interval (95% CI) 3.6 to 12.4). The risk of death in men with intermittent claudication was substantially raised. After standardisation for age and smoking the relative odds of death was 3.8 (95% CI 2.2 to 6.5). The excess was entirely from circulatory causes. Systolic blood pressure, fasting plasma glucose, triglycerides, and white cell count were all independently associated with the development of intermittent claudication, but the most striking association was with smoking. CONCLUSIONS: Intermittent claudication is an indicator for a very high risk of death. This is only partly explained by its strong association with ischaemic heart disease.

Age Factors↗

Associations of the HDL2 and HDL3 cholesterol subfractions with the development of ischemic heart disease in British men. The Caerphilly and Speedwell Collaborative Heart Disease Studies.

BACKGROUND: The relative importance of HDL2 and HDL3 cholesterol as risk factors for ischemic heart disease (IHD) is still uncertain. Their associations with the incidence of IHD in the Caerphilly and Speedwell prospective studies are described. METHODS AND RESULTS: The two studies have a common core protocol and are based on a total of 4860 middle-aged men from the general population. The first follow-up was at a nearly constant interval of 5.1 years in Caerphilly and 3.2 years in Speedwell: 251 major IHD events had occurred. Lipid levels were measured on fasting samples. Different laboratories were used by the two studies. Each laboratory used ultracentrifugation to separate HDL2 and HDL3. Both subfractions were inversely associated with risk of IHD. Standardized relative odds of developing major IHD were 0.95 (95% confidence interval [CI], 0.80 to 1.14) for HDL2 cholesterol and 0.83 (95% CI, 0.68 to 1.00) for HDL3 cholesterol in Caerphilly and 0.76 (95% CI, 0.57 to 1.01) for HDL2 and 0.64 (95% CI, 0.49 to 0.83) for HDL3 in Speedwell. The association with incident IHD appeared to be stronger for HDL3 in both areas. No linear combination of the two subfractions was a better predictor of IHD than total HDL cholesterol alone. CONCLUSIONS: In British men, both HDL2 and HDL3 cholesterol are inversely associated with the incidence of IHD. However, the prediction of the risk of IHD from total HDL cholesterol alone could not be improved upon by measurement of the two HDL subfractions. The relative value of the two HDL subfractions as predictors of risk is still unresolved. The uncertainty may be due, at least in part, to problems associated with their measurement.

Cholesterol, HDL↗

Temperature and risk factors for ischaemic heart disease in the Caerphilly prospective study.

OBJECTIVE: To examine the associations between air temperature and risk factors for ischaemic heart disease. METHOD: Data on risk factors are available from up to 2036 men in the Caerphilly Prospective Heart Disease Study. Daily temperatures were obtained from the Meteorological Office. Relations between these were examined by regression. RESULTS: The coldest month of the year has a mean temperature that is 16 degrees C lower than that in the warmest month. A fall in temperature of this magnitude is associated with higher blood pressures (by 3-5 mm Hg) and a lower concentration of high density lipoprotein cholesterol (by 0.08 mmol/l). The most important effects however, seem to be on the haemostatic system. Fibrinogen is 0.34 g/l higher in the coldest month than in the warmest (p < 0.001) and alpha 2 macroglobulin, a protein that inhibits fibrinolysis, is also raised. Platelet count is increased by 30% of a standard deviation and the sensitivity of platelets in whole blood to adenosine diphosphate is increased by cold. CONCLUSIONS: These effects on haemostasis, together with the effect on blood pressure, could explain a large part of the increase in ischaemic heart disease in the winter but are unlikely to explain much of the difference in mortality within different areas of England and Wales.

Adenosine Diphosphate↗

Plasma triglyceride and high density lipoprotein cholesterol as predictors of ischaemic heart disease in British men. The Caerphilly and Speedwell Collaborative Heart Disease Studies.

OBJECTIVE: To assess the roles of plasma triglyceride and high density lipoprotein (HDL) cholesterol concentrations in predicting ischaemic heart disease. DESIGN: Two prospective cohort studies with common core protocols. SETTING AND PARTICIPANTS: Both cohorts are 100% samples of middle aged men. In Caerphilly the 2512 men were living within a defined area. In Speedwell the 2348 men were registered with local general practitioners. MAIN OUTCOME MEASURES: Fasting blood samples were taken at initial examination and plasma lipid concentrations were measured. Major ischaemic heart disease events were assessed from hospital notes, death certificates, and electrocardiograms. RESULTS: At first follow up, after an average of 5.1 years in Caerphilly and 3.2 years in Speedwell, 251 major ischaemic heart disease events had occurred. Men with triglyceride concentrations in the top 20% of the distribution had a relative odds value for ischaemic heart disease of 2.3 (95% confidence interval (95% CI) 1.3 to 4.1) compared with men in the bottom 20%, after adjusting for both plasma total and HDL cholesterol, and non-lipid risk factors. Men in the lowest 20% of the distribution of HDL cholesterol concentration had a relative odds value of 1.7 (95% CI 1.0 to 2.8) compared with the top 20%, after adjustment was made for total cholesterol and triglyceride concentrations, and non-lipid risk factors. These relations were not caused by beta blockers, which were being taken by 5% of the men. CONCLUSIONS: Plasma triglyceride concentration predicts major ischaemic events after allowance is made for total and HDL cholesterol concentrations and other risk factors. In these populations, triglyceride is a more important predictor than total cholesterol concentration.

Adrenergic beta-Antagonists↗

Fibrinogen, viscosity, and white blood cell count are major risk factors for ischemic heart disease. The Caerphilly and Speedwell collaborative heart disease studies.

BACKGROUND: Recent studies have suggested that hemostatic factors and white blood cell count are predictive of ischemic heart disease (IHD). The relations of fibrinogen, viscosity, and white blood cell count to the incidence of IHD in the Caerphilly and Speedwell prospective studies are described. METHODS AND RESULTS: The two studies have a common core protocol and are based on a combined cohort of 4,860 middle-aged men from the general population. The first follow-up was at a nearly constant interval of 5.1 years in Caerphilly and 3.2 years in Speedwell; 251 major IHD events had occurred. Age-adjusted relative odds of IHD for men in the top 20% of the distribution compared with the bottom 20% were 4.1 (95% confidence interval, 2.6-6.5) for fibrinogen, 4.5 (95% confidence interval, 2.8-7.4) for viscosity, and 3.2 (95% confidence interval, 2.0-4.9) for white blood cell count. Associations with IHD were similar in men who had never smoked, exsmokers, and current smokers, and the results suggest that at least part of the effect of smoking on IHD is mediated through fibrinogen, viscosity, and white blood cell count. Multivariate analysis shows that white blood cell count is an independent risk factor for IHD as is either fibrinogen or viscosity, or possibly both. Jointly, these three variables significantly improve the fit of a logistic regression model containing all the main conventional risk factors. Further, a model including age, smoking habits, fibrinogen, viscosity, and white blood cell count predicts IHD as well as one in which the three hemostatic/rheological variables are replaced by total cholesterol, diastolic pressure, and body mass index. CONCLUSION: Jointly, fibrinogen, viscosity, and white blood cell count are important risk factors for IHD.

Blood Viscosity↗

The diets of men in four areas of the UK: the Caerphilly, Northern Ireland, Edinburgh and Speedwell studies.

Nutrient intakes in four areas of the UK were compared, 7-d weighed intake data were obtained for representative community samples of middle-aged men in Caerphilly (South Wales), Northern Ireland, Edinburgh and Bristol (Speedwell). Intakes of energy were higher in Edinburgh than in the other three areas, but following allowance for this, differences in nutrient intakes were very small. The exceptions were P/S ratio and alcohol consumption. The P/S ratio for Northern Ireland (0.38) was considerably higher than that for the other areas (0.30 to 0.32). The proportion of heavy drinkers was higher in Edinburgh (15 per cent) than in other areas (5-9 per cent) and the proportion of abstainers was highest in Northern Ireland (38 per cent). Differences in nutrient intakes did not parallel the differences in ischaemic heart disease (IHD) mortality rates between the areas.

Alcohol Drinking↗

Haemostatic and other risk factors for ischaemic heart disease and social class: evidence from the Caerphilly and Speedwell studies.

There are marked associations between social class and mortality from ischaemic heart disease (IHD). Using data from the Caerphilly and Speedwell Collaborative Heart Disease Studies the relationships between a number of known risk factors for IHD and social class are explored. The overall conclusions are that lipids and obesity are unlikely to play any part in explaining social differences in ischaemic heart disease. Blood pressure, particularly stystolic pressure, could be involved but the two data sets are inconsistent and associations are only shown in Speedwell. There are marked differences in the haemostatic related variables in the various social classes and the pattern of these is similar in Caerphilly and Speedwell. It is possible therefore that the class pattern of IHD is generated, in part at least, by differences in haemostatic mechanisms. These differences in haemostatic function are almost entirely due to the large social class differences in smoking habit. It is possible therefore that the class differences in IHD result from differences in smoking habit.

Blood Pressure↗

Prevalence of ischaemic heart disease: the Caerphilly and Speedwell surveys.

Mortality from ischaemic heart disease remains high in the United Kingdom, and the present report describes the prevalence of the various epidemiological manifestations of the disease in two recent community studies with a common core protocol, each containing samples of over 2000 men, carried out in South Wales (Caerphilly) and the West of England (Speedwell, Bristol). The prevalence of electrocardiographic evidence of ischaemia was similar in the two communities--8.7% of men aged 45-49 years rising to 18.6% in men aged 55-59 years in the samples from South Wales, and 8.0% and 17.2% respectively in the Bristol population. The overall prevalence of angina was 7.7% in Caerphilly and 7.8% in Speedwell in men aged 45-59 years, but symptoms of severe chest pain were more commonly reported in South Wales than in Speedwell (10.1% compared with 6.3%). The data, however, suggested that the overall prevalence of ischaemic heart disease was very similar in the two areas. The prevalence of ischaemic heart disease was compared with that found in other population studies carried out in the United Kingdom and was higher than that found when employed men only were studied. There were substantial differences in mortality between the two areas; possible reasons for this are differences in community or medical services, smoking habit, or unemployment rates.

Age Factors↗

Diagnosis of past history of myocardial infarction in epidemiological studies: an alternative based on the Caerphilly and Speedwell surveys.

In epidemiological studies the diagnosis of a past history of myocardial infarction is made from the answer to a single question: "Have you ever had a severe pain across the front of your chest lasting for half an hour or more?" Two additional questions, which form an optional part of the London School of Hygiene and Tropical Medicine chest pain questionnaire, were used in two large community studies, with other information to determine the likely accuracy of the diagnosis ("Did you see a doctor about this pain?" If so, "What did he say it was?") The prevalence of possible myocardial infarction from the use of the single question was significantly higher among men from South Wales than among men from Speedwell, Bristol (10.1% and 6.9% respectively); in contrast, positive responses to the additional questions reduced the prevalence in the two populations to 5.8% and 4.9% respectively. These latter figures are very similar to those of self-reported coronary thrombosis in the two populations. Among subjects with positive responses to the additional questions the prevalence of ECG ischaemia was about 50%; in contrast, the prevalence of ECG ischaemia among those positive only to the severe chest pain question was very similar to that among those with no history of chest pain (12%). Preliminary mortality data show a similar classification of level of risk. These findings indicate that the false positive error rate for possible myocardial infarction could be significantly reduced by the use of two additional questions which form an optional part of the London School of Hygiene chest pain questionnaire but are rarely used. However, the present findings relate to populations with uniform levels of adequately accessible medical care; comparisons between populations with different levels of medical care will require cautious interpretation.

Chest Pain↗

Associations of alcohol consumption with plasma high density lipoprotein cholesterol and its major subfractions: the Caerphilly and Speedwell Collaborative Heart Disease Studies.

In surveys of 4860 middle-aged men in Caerphilly (South Wales) and Speedwell (Bristol) alcohol consumption has been related to high density lipoprotein (HDL) cholesterol and its major subfractions, HDL2 and HDL3, measured in a single fasting blood sample. The results confirm that high density lipoprotein cholesterol concentration increases as the amount of alcohol regularly consumed increases. The relationship appears to be linear and is independent of age, smoking habit, body mass index, low density lipoprotein cholesterol and plasma total triglyceride. This rise in HDL cholesterol is not mediated through either HDL2 cholesterol or HDL3 cholesterol alone. Both subclasses increase significantly and by similar amounts with increasing alcohol intake.

Alcohol Drinking↗

DNA polymorphisms of the apolipoprotein AII and AI-CIII-AIV genes: a study in men selected for differences in high-density-lipoprotein cholesterol concentration.

We have investigated the frequencies of RFLPs of the apolipoprotein (apo) AII gene and of the apo AI-CIII-AIV gene cluster in 109 men, selected from a random sample of 1,910 men aged 45-59 years, to cover a wide range of plasma high-density-lipoprotein (HDL)-cholesterol concentration. There was no significant difference in apo AI or apo AII RFLP allele frequency between groups of individuals with high and low HDL-cholesterol concentration. However, the apo AI PstI RFLP showed an association with genetic variation determining the plasma concentration of apo AI in this sample. Genetic variation in the apo AI-CIII-AIV gene region, as defined by haplotypes, accounted for 16% of the phenotypic variance in the apo AI concentration and for 8% of the phenotypic variance in HDL-cholesterol concentration. There was no significant association between alleles of the apo AII MspI RFLP and genetic variation determining apo AII or HDL concentration. The data demonstrate that genetic variation in the apo AI-CIII-AIV gene cluster is involved in determining the serum concentration of apo AI in this sample of clinically well individuals.

Alleles↗

Benoxaprofen--adverse reactions and monitoring in general practice.

We report on the pattern of use of benoxaprofen (Opren) in a single group practice for a period which included the complete clinical life of the drug. One hundred and seventy-two patients of the 6495 practice patients had been prescribed benoxaprofen, but 55% had only a small exposure (less than 20 g). Recorded adverse reactions, of which none was serious, appeared in 25 patients. Most were taking benoxaprofen for osteoarthritis (53%) or non-specific musculoskeletal pain (39.9%). The issue of a prescription was not recorded in 19.6% of cases and 88% were on additional drugs. Greater precision in record-keeping is required to avoid problems similar to the experience with benoxaprofen.

Adolescent↗

Some long term effects of smoking on the haemostatic system: a report from the Caerphilly and Speedwell Collaborative Surveys.

Data from two community studies on men from South Wales and the west of England suggest that the effects of smoking on the haemostatic system remain for many years after giving up. Long term correlations between several variables, including plasma fibrinogen and white cell count, and the length of time after giving up were seen in ex-smokers. Dose response relations were apparent in current smokers in terms of the white cell count and two haematological variables, the packed and mean cell volumes. These long term correlations probably reflect the toxicity of other agents in tobacco smoke besides nicotine and carbon monoxide, which act only in the short term. Identification of these agents may further our understanding of the mechanism by which cigarette smoking is associated with atherosclerotic disease.

Blood Viscosity↗

Controlled trial of a home-care service for acute stroke patients.

In a controlled trial of a home-care service available for the first 6 months after acute stroke, 440 patients received the new service and 417 patients were in the control group. The trial group used more hospital bed days, had a slightly higher admission rate, and did not show better emotional adjustment to stroke than the control group. There was no difference between the 2 groups in stress on relatives. Functional recovery was equal in the 2 groups. A quarter of patients managed at home in each group were severely disabled. Providing a new service does not necessarily alter clinical decisions in the short term, and care should be taken before expanding domiciliary services to reduce hospital use.

Acute Disease↗