Search PubMed⌕ Search

Biomedical subjects

A G Shaper

Publications and source records attributed to A G Shaper.

At least 19 recordsLinked to original sources
PubMed1992

Leukocyte count and risk of major coronary heart disease events.

The association between leukocyte count and subsequent risk of major coronary heart disease events was examined using data from three prospective cohort studies--two from the United States and one from Great Britain. A total of 28,181 middle-aged men were followed for 6-12 years. A total of 1,768 men had a nonfatal myocardial infarction or died of coronary heart disease. In all three cohorts, there was a positive, statistically significant relation between baseline leukocyte count and risk of subsequent major coronary heart disease events after adjustment for age, serum total cholesterol, diastolic blood pressure, and number of cigarettes smoked per day (relative odds = 1.32 (p less than 0.0001), 1.15 (p = 0.0001), and 1.14 (p = 0.003), corresponding to a 2,000/mm3 difference in leukocyte count). The associations persisted when all nonsmokers (former smokers plus never smokers) and never smokers alone were considered and when those with evidence of preexisting coronary heart disease at baseline were excluded. Leukocyte count appears to be an indicator of a person's future risk of major coronary heart disease events.

Adult↗
PubMed1992

Stroke.

Explore the source record for details and available documents.

Blood Pressure↗
PubMed1992

Physical activity and stroke in British middle aged men.

OBJECTIVES: To assess the relation between physical activity and stroke and to determine the overall benefit of physical activity for all major cardiovascular events. DESIGN: Prospective study of a cohort of men followed up for 9.5 years. SETTING: General practices in 24 towns in England, Wales, and Scotland (British regional heart study). SUBJECTS: 7735 men aged 40-59 at screening, selected at random from one general practice in each of 24 towns. MAIN OUTCOME MEASURES: Fatal and non-fatal strokes and heart attacks. RESULTS: 128 major strokes (fatal and non-fatal) occurred. Physical activity was inversely associated with risk of stroke independent of coronary risk factors, heavy drinking, and pre-existing ischaemic heart disease or stroke (relative risk 1.0 for inactivity, 0.6 moderate activity, and 0.3 vigorous activity; test for trend p = 0.008). The association remained after excluding men reporting regular sporting (vigorous) activity. However, vigorous physical activity was associated with a marginally significant increased risk of heart attack compared with moderate or moderately vigorous activity in men with no pre-existing ischaemic heart disease or stroke (relative risk 1.6%; 95% confidence interval 0.96 to 2.8). In men with symptomatic ischaemic heart disease or stroke those doing moderately vigorous or vigorous activity had a risk of heart attack slightly higher than that in inactive men (relative risk = 1.6; 0.8 to 3.3). CONCLUSIONS: Moderate physical activity significantly reduces the risk of stroke and heart attacks in men both with and without pre-existing ischaemic heart disease. More vigorous activity did not confer any further protection. Moderate activity, such as frequent walking and recreational activity or weekly sporting activity, should be encouraged without restriction.

Adult↗
PubMed1992

Non-employment and changes in smoking, drinking, and body weight.

OBJECTIVE: To assess the effect of unemployment and early retirement on cigarette smoking, alcohol consumption, and body weight in middle aged British men. DESIGN: Prospective cohort study (British regional heart study). SETTING: One general practice in 24 towns in Britain. SUBJECTS: 6057 men aged 40-59 who had been continuously employed for five years before the initial screening. Five years after screening 4412 men had been continuously employed and 1645 had experienced some unemployment or retired. MAIN OUTCOME MEASURES: Numbers of cigarettes smoked and units of alcohol consumed per week and body mass index (kg/m2). RESULTS: An initial screening significantly higher percentages of men who subsequently experienced non-employment smoked or had high alcohol consumption than of men who remained continuously employed: 43.0% versus 37.0% continuously employed for cigarette smoking (95% confidence interval for difference 3.2% to 9.0%) and 12.1% versus 9.0% for heavy drinking (1.3% to 5.1%). There was no evidence that men increased their smoking or drinking on becoming non-employed. Men non-employed through illness were significantly more likely to reduce their smoking and drinking than men who remained continuously employed. Men who experienced non-employment were significantly more likely to gain over 10% in weight than men who remained continuously employed: 7.5% versus 5.0% continuously employed (0.9% to 4.0%). CONCLUSIONS: Loss of employment was not associated with increased smoking or drinking but was associated with an increased likelihood of gaining weight. The long term effects of the higher levels of smoking and alcohol consumption before nonemployment should be taken into account when comparing mortality and morbidity in groups of unemployed and employed people.

Adult↗
PubMed1992

The leukocyte count and risk of lung cancer.

The association between leukocyte count and subsequent risk of lung cancer was evaluated in three large cohorts from the United States and Britain. A total of 309 lung cancer events occurred among 28,181 men whose cases were followed-up for 7 to 12 years. In all three cohorts, there was a marked increase in risk of lung cancer with increasing leukocyte count, after adjustment for age and the number of cigarettes smoked per day. The adjusted relative odds in the three cohorts, for a 2000/microliters difference in leukocyte count, were 1.58 (P = 0.0001), 1.29 (P = 0.003) and 1.20 (P = 0.02). These relative odds persisted when current smokers were considered alone, when serum markers of cigarette smoking exposure were adjusted for, and when men with lung cancer events during the first 5 years of follow-up were excluded. The leukocyte count appears to be linked to the pathogenesis of smoking-related lung cancer.

Adult↗
PubMed1992

Alcohol and sudden cardiac death.

OBJECTIVE: To assess the relation between alcohol intake and sudden cardiac death--ie, death within one hour of the onset of symptoms. DESIGN: Prospective study of a cohort of men followed up for eight years. SETTING: General practices in 24 towns in England, Wales, and Scotland. SUBJECTS: 7735 men aged 40-59 at screening who were selected at random from one general practice in each of 24 towns. MAIN OUTCOME MEASURE: All deaths from ischaemic heart disease with particular reference to those that were sudden (death within one hour of the onset of symptoms). RESULTS: During the follow up period of eight years there were 217 deaths from ischaemic heart disease of which 117 (54%) were classified as sudden. Although heavy drinkers (more than six drinks daily) did not show a high incidence rate of fatal heart attack, they showed the highest incidence rate of sudden cardiac death. This was seen in both manual and non-manual workers and was most clearly seen in older (50-59) men. Death from ischaemic heart disease was more likely to be sudden in heavy drinkers than in other drinking groups; this phenomenon was seen irrespective of the presence or degree of pre-existing ischaemic heart disease. The positive association between heavy drinking and the incidence of sudden death was most apparent in men without pre-existing ischaemic heart disease, with heavy drinkers showing an increase of > 60% compared with occasional or light drinkers. After adjustment for age, social class, and smoking, heavy drinkers free of pre-existing ischaemic heart disease had a marginally significantly higher incidence rates of sudden death than other drinkers combined (relative risk 2.00, 95% confidence interval 0.98 to 4.8). Additional adjustment for systolic blood pressure reduced the risk to 1.7. CONCLUSIONS: This study suggests that heavy drinking is associated with an increased risk of sudden death. Studies that do not take pre-existing ischaemic heart disease into account are likely to underestimate the adverse effects of heavy drinking on the incidence of sudden death because the effects are not as evident in men with pre-existing ischaemic heart disease.

Adult↗
PubMed1992

The Dinamap 1846SX automated blood pressure recorder: comparison with the Hawksley random zero sphygmomanometer under field conditions.

STUDY OBJECTIVE: The aim was to compare the performance of the Dinamap 1846SX automated oscillometric blood pressure recorder with that of the Hawksley random zero sphygmomanometer during use under field study conditions. DESIGN: Two independent within subject measurement comparisons were made, one in adults and one in children, each conducted in three stages over several months while the Dinamap instruments were being used in epidemiological field surveys. SETTING: The studies were done in outpatients clinics (adults) and primary schools (children). PARTICIPANTS: 141 adults (20-85 years) and 152 children (5-7 years) took part. MEASUREMENTS AND MAIN RESULTS: In adults a pair of measurements was made with each instrument, the order alternating for consecutive subjects. In children one measurements was made with each instrument, in random order. Measurements with the Dinamap 1846SX were higher than those with the random zero sphygmomanometer both in adults (mean difference 8.1 mm Hg; 95% CI 6.5 to 9.7 mm Hg) and in children (mean difference 8.3 mm Hg; 95% CI 6.9 to 9.7 mm Hg). Diastolic measurements were on average very similar both in adults and in children. The results were consistent at all three stages of both studies. The differences in systolic measurement were independent of blood pressure level. However, the extent of agreement in diastolic pressure depended on the diastolic blood pressure level; in both studies Dinamap diastolic measurements were higher at low diastolic pressures while random zero diastolic measurements were higher at high diastolic pressures. CONCLUSIONS: Systolic measurements made with the Dinamap 1846SX instrument are not directly comparable with those of the Hawksley random zero sphygmomanometer and are unlikely to be comparable with those of earlier Dinamap models. These differences have important implications for clinical practice and for comparisons of blood pressure measurement between epidemiological studies. However, the consistency of measurement by the Dinamap 1846SX over time suggests that the instrument may have a place in standardised blood pressure measurement in the research setting.

Adult↗
PubMed1992

Blood lipids: the relationship with alcohol intake, smoking, and body weight.

STUDY OBJECTIVE: The aim was to assess the interrelationship between alcohol intake, cigarette smoking, body weight, and blood lipid concentrations. DESIGN: This was the cross sectional (screening) phase of a prospective study. The main outcome measure was the blood lipids (serum total cholesterol, HDL cholesterol, and triglycerides). SETTING: General practices in 24 towns (The British Regional Heart Study). SUBJECTS: Subjects were 7735 men aged 40-59 years, selected at random from the age-sex registers of one group practice in each of the 24 towns. RESULTS: Univariate analysis showed little association between alcohol intake and total cholesterol, a strong positive relation with HDL cholesterol, and a significant increase in triglycerides in heavy drinkers. A strong positive association between alcohol intake and body weight was present in non-smokers but not in moderate/heavy smokers. With the exception of HDL cholesterol, the relationships between alcohol intake and serum lipids were significantly different in smokers and non-smokers, apparently due to the opposing effect of smoking on blood lipids and body weight. Total cholesterol and triglycerides were significantly and positively associated with alcohol intake in non-smokers, the cholesterol association being largely mediated by the influence of alcohol on body weight. In smokers, no such association was seen: current smokers who were heavy drinkers or non-drinkers had the lowest mean cholesterol levels. CONCLUSIONS: The association between alcohol intake and body weight and alcohol intake and blood lipids are strongly conditioned by cigarette smoking. Simple standardisation for smoking in multivariate analyses may obscure the independent relationship with alcohol. These findings are of importance in studies seeking to relate alcohol intake, body weight, or cigarette smoking to blood lipid concentrations, or blood lipid concentration to morbidity or mortality.

Adult↗
PubMed1992

Non-consulters and high consulters in general practice: cardio-respiratory health and risk factors.

The 1990 General Practitioner contract requires that health promotion and illness prevention services should be provided to all patients aged 16-74 years. Consultation rates over a period of three years were examined in 7010 middle-aged men in Great Britain to compare the cardio-respiratory health and risk factor status of non-consulters (men who did not consult in three years) with those of average consulters (men who consulted 3-5 times in three years) and high consulters (men who consulted 24 or more times in three years) to assess their relative need for health promotion and illness prevention services. The non-consulters (n = 1025) were remarkably similar to the average consulters (n = 1585) in health and lifestyle characteristics. The high consulters (n = 306) had a greater burden of ill-health and a less healthy lifestyle. Chest pain on exertion, chronic bronchitis, breathlessness or wheeze were present in 23 per cent of non-consulters, 27 per cent of average consulters and over 50 per cent of high consulters. Similarly, 48 per cent of the non-consulters smoked, drank heavily or were obese compared with 47 per cent of the average consulters and 61 per cent of the high consulters. The prevalence of recall of high blood pressure which had been diagnosed by a doctor rose from 6 per cent in non-consulters and 10 per cent in average consulters to 29 per cent in high consulters.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Casual urine concentrations of sodium and potassium and geographic blood pressure variations in Great Britain.

The associations between blood pressure and urine sodium, potassium and creatinine have been studied among 1,240 men and 1,119 women living in nine British towns in order to assess the contribution of sodium and potassium intake to geographic BP variations within Great Britain. Significant positive associations were found between systolic BP and the urine sodium/potassium ratio for men (P less than 0.05) and for women (P less than 0.001), and for the sodium/creatinine ratio in men (P less than 0.01), after adjustment for age and body mass index. The findings for diastolic BP were similar, but non-significant for men. Associations between BP and sodium concentration were inconsistent and non-significant. The associations between BP and potassium concentration were consistently negative, and significant for diastolic in women (P less than 0.01). The correlations between the mean town systolic BPs and the sodium/potassium ratio were 0.65 (P = 0.058) for men, and 0.60 (P = 0.086) for women. Correlations for diastolic BP were such smaller. The association between BP and the sodium/potassium ratio in this study is consistent both within and between populations, although more so for women than for men. The results are also consistent with the results of other population studies using casual and 24 urine specimens. Although unable to quantify the effects of sodium and potassium with precision, the study suggests that the sodium/potassium ratio is of importance in geographic BP variations in Great Britain, at least for systolic blood pressure.

Adult↗
PubMed1991

Risk factors for stroke in middle aged British men.

OBJECTIVE: To determine the risk factors for stroke in a cohort representative of middle aged British men. DESIGN: Prospective study of a cohort of men followed up for eight years. SETTING: General practices in 24 towns in England, Wales, and Scotland (the British regional heart study). SUBJECTS: 7735 men aged 40-59 at screening, selected at random from one general practice in each town. MAIN OUTCOME MEASURE: Fatal and non-fatal strokes. RESULTS: 110 of the men had at least one stroke; there were four times as many non-fatal as fatal strokes. The relative risk of stroke was 12.1 in men who had high blood pressure (systolic blood pressure greater than or equal to 160 mm Hg) and were current smokers compared with normotensive, non-smoking men. Diastolic blood pressure yielded no additional information, and former cigarette smokers had the same risk as men who had never smoked. Heavy alcohol intake was associated with a relative risk of stroke of 3.8 in men without previously diagnosed cardiovascular disease. Men with pre-existing ischaemic heart disease had an increased risk of stroke, but only when left ventricular hypertrophy on electrocardiography was also present. CONCLUSIONS: Systolic blood pressure, cigarette smoking, and left ventricular hypertrophy on electrocardiography in men with pre-existing ischaemic heart disease were found to be the major risk factors for stroke in middle aged British men. Heavy alcohol intake seemed to increase the risk of stroke in men without previously diagnosed cardiovascular disease. A large proportion of strokes should be preventable by controlling blood pressure and stopping smoking.

Alcohol Drinking↗
PubMed1991

Early life experience and adult cardiovascular disease: longitudinal and case-control studies.

It has been postulated that experiences early in life influence cardiovascular risk in later adult life. This article considers 15 longitudinal and four case-control studies which, directly or indirectly, have examined the hypothesis concerning the prenatal and childhood origins of adult cardiovascular disease. Criteria laid down by Bradford Hill were used to assess whether these epidemiological studies provided sufficient evidence for a causal relation between experiences early in life and subsequent cardiovascular risk. No consistent dose-response relationship was found between the index of early life experience and adult cardiovascular disease. The relationships were usually non-specific with the index of early life experience being correlated with several causes of death, not only cardiovascular disease. The formulation of the hypothesis varied between the studies. Most reports dealt inadequately with the fact that the relation between adult cardiovascular risk and early life experience was confounded by persisting social and economic disadvantage. Overall these studies do not provide strong support for the hypothesis that experiences early in life determine the subsequent risk of cardiovascular disease. While future epidemiological studies may resolve this issue, the very nature of the hypothesis presents methodological problems that may prove to be insurmountable. Further progress in this field urgently requires the formulation of a clear and specific hypothesis.

Adult↗
PubMed1991

The contribution of environmental temperature and humidity to geographic variations in blood pressure.

The pattern of geographic blood pressure variations in Britain has raised the possibility that temperature or other climatic factors may be of importance. Data from two population studies have been examined: the British Regional Heart Study (BRHS), which involved 7735 mean aged 40-59 years, and the Nine Towns Study (NTS), concerning blood pressure among 2596 men and women aged 25-59 years. In the BRHS, significant negative associations were found between daily maximum outdoor temperature and systolic blood pressure (-0.38 mmHg/degrees C; P less than 0.001) and diastolic blood pressure (-0.18 mmHg/degrees C; P less than 0.001). There were similar, although non-significant, associations in the NTS. No significant associations were found between blood pressure and room temperature in either study after taking account of town blood pressure differences, nor between blood pressure and outdoor humidity in the NTS. In the NTS, skin temperature was negatively associated with blood pressure after the adjustment for body mass index, significantly so for male diastolic (-0.62 mmHg/degrees C; P less than 0.05). The BRHS estimates suggest that, in Britain, geographic differences in outdoor temperature may contribute no more than 2 mmHg systolic and 1 mmHg diastolic to regional blood pressure variations. This represents a relatively small proportion of the town differences in blood pressure observed in both the BRHS and NTS. Furthermore, international comparisons suggest that environmental temperature is not an important determinant of population blood pressure levels.

Adult↗
PubMed1991

Physical activity and ischaemic heart disease in middle-aged British men.

OBJECTIVE: To assess the relation between reported physical activity and the risk of heart attacks in middle aged British men. DESIGN: Prospective study of middle-aged men followed for a period of eight years (The British Regional Heart Study). SETTING: One general practice in each of 24 British towns. PARTICIPANTS: 7735 men aged 40-59 years at initial examination. END POINT: Heart attacks (non-fatal and fatal). MEASUREMENTS AND MAIN RESULTS: During the follow up period of eight years 488 men suffered at least one major heart attack. A physical activity score used was developed and validated against heart rate and lung function (FEV1) in men without evidence of ischaemic heart disease. Risk of heart attack decreased significantly with increasing physical activity; the groups reporting moderate and moderately vigorous activity experienced less than half the rate seen in inactive men. The benefits of physical activity were seen most consistently in men without preexisting ischaemic heart disease and up to levels of moderately vigorous activity. Vigorously active men had higher rates of heart attack than men with moderate or moderately vigorous activity. The relation between physical activity and the risk of heart attack seemed to be independent of other cardiovascular risk factors. Men with symptomatic ischaemic heart disease showed a reduction in the rate of heart attack at light or moderate levels of physical activity, beyond which the risk of heart attack increased. Men with asymptomatic ischaemic heart disease showed an increasing risk of heart attack with increasing levels of physical activity, but with a progressive decrease in case fatality. Overall, men who engaged in vigorous (sporting) activity of any frequency had significantly lower rates of heart attack than men who reported no sporting activity. However, when all men reporting regular sporting activity at least once a month were excluded from analysis, there remained a strong inverse relation between physical activity and the risk of heart attack in men without pre-existing ischaemic heart disease. CONCLUSION: This study suggests that the overall level of physical activity is an important independent protective factor in ischaemic heart disease and that vigorous (sporting) exercise, although beneficial in its own right, is not essential in order to obtain such an effect.

Adult↗