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H Tunstall-Pedoe

Publications and source records attributed to H Tunstall-Pedoe.

At least 19 recordsLinked to original sources
PubMed2001

Association of dietary antioxidants and waist circumference with pulmonary function and airway obstruction.

Dietary antioxidants, waist circumference, and pulmonary function were measured in the Fourth Scottish MONICA cross-sectional survey of 865 men and 971 women aged 25-64 years. Waist circumference was inversely related to forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC), even after adjustment for age, height, weight, working status, energy intake, and smoking variables in a multiple linear regression model (men: beta = -0.017 for FEV1 l/cm, p < 0.01 and beta = -0.008 for FVC, p = 0.04; women: beta = -0.009 for FEV1, p < 0.01 and beta = -0.007 for FVC, p = 0.01). After additional adjustment for waist circumference, estimated vitamin C and beta-carotene intakes were positively associated with lung function in men (vitamin C: beta = 0.102 for FEV1 l/mg/day, p = 0.03; beta-carotene: beta = 0.073 for FVC l/g/day, p = 0.02). Retinol and vitamin E were not significantly related to lung function for either sex. A case-control study of airway obstruction showed that waist circumference was significantly associated, while vitamin C could be protective. The study suggests that adequate intake of antioxidants and avoidance of increasing girth could help to preserve lung function.

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PubMed2001

Helicobacter pylori infection reduces systemic availability of dietary vitamin C.

OBJECTIVE: Helicobacter pylori infection is recognized to lower the concentration of vitamin C in gastric juice. The objective of this study was to assess the effect of the infection on the systemic availability of dietary vitamin C. METHODS: The study involved 1,106 men and women aged 25-74 randomly recruited from the population of north Glasgow. Their H. pylori status, dietary vitamin C intake calculated from a food frequency questionnaire and plasma vitamin C concentration were measured. Correction was made for potential confounding factors such as age, sex, smoking and social status. RESULTS: The mean plasma vitamin C concentration in those who were H. pylori-positive was only 65% of that in those classified negative. Although partly explained by differences in age, sex, social class, smoking and vitamin C intake, the systemic reduction was observed across almost all sub-groups after stratification. Correction for all these factors still gave a plasma vitamin C level for H. pylori positives which was only 80% of that for negatives (P < 0.0001). CONCLUSIONS: H. pylori substantially impairs the bio-availability of vitamin C. This, together with the reduced vitamin C intake of H. pylori-positive subjects, markedly reduces the plasma vitamin C level of infected subjects. The reduced circulating levels of vitamin C in H. pylori-infected subjects may contribute to the aetiology of gastric cancer, as well as other diseases associated with anti-oxidant deficiency.

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PubMed2001

Environmental tobacco smoke and lung function in employees who never smoked: the Scottish MONICA study.

OBJECTIVES: To investigate the relation between lung function in employees and exposure to environmental tobacco smoke (ETS) at work and elsewhere. METHODS: Never smokers in employment (301) were identified from the fourth Scottish MONICA survey. They completed a self administered health record, which included details of exposure to ETS, and attended a survey clinic for physical and lung function measurements, and for venepuncture for estimation of serum cotinine. Differences in lung function in groups exposed to ETS were tested by analysis of variance (ANOVA), the exposure-response relation by a linear regression model, and a case-control analysis undertaken with a logistic regression model. RESULTS: Both men and women showed effects on forced expiratory volume in the first second (FEV(1)) and forced vital capacity (FVC) from exposure to ETS-higher exposure going with poorer lung function. This was found at work, and in total exposure estimated from ETS at work, at home, and at other places. Linear regression showed an exposure-response relation, significant for ETS at work, total exposure, and exposure time/day, but not at home or elsewhere. Compared with those not exposed to ETS at work, those who were exposed a lot had a 254 ml (95% confidence interval (95% CI) 84 to 420) reduction in FEV(1), and a 273 ml (60 to 480) reduction in FVC after adjusting for confounders. Although lung function was not significantly associated with serum cotinine in all the data, a significant inverse relation between cotinine concentration and FVC occurred in men who had had blood collected in the morning. Case-control analysis also showed a significant exposure-response relation between ETS, mainly at work, and lung function. A higher exposure measured both by self report and serum cotinine went with lower lung function. CONCLUSION: The exposure-response relation shows a reduction in pulmonary function of workers associated with passive smoking, mainly at work. These findings endorse current policies of strictly limiting smoking in shared areas, particularly working environments.

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PubMed2000

Estimation of contribution of changes in classic risk factors to trends in coronary-event rates across the WHO MONICA Project populations.

BACKGROUND: From the mid-1980s to mid-1990s, the WHO MONICA Project monitored coronary events and classic risk factors for coronary heart disease (CHD) in 38 populations from 21 countries. We assessed the extent to which changes in these risk factors explain the variation in the trends in coronary-event rates across the populations. METHODS: In men and women aged 35-64 years, non-fatal myocardial infarction and coronary deaths were registered continuously to assess trends in rates of coronary events. We carried out population surveys to estimate trends in risk factors. Trends in event rates were regressed on trends in risk score and in individual risk factors. FINDINGS: Smoking rates decreased in most male populations but trends were mixed in women; mean blood pressures and cholesterol concentrations decreased, bodymass index increased, and overall risk scores and coronary-event rates decreased. The model of trends in 10-year coronary-event rates against risk scores and single risk factors showed a poor fit, but this was improved with a 4-year time lag for coronary events. The explanatory power of the analyses was limited by imprecision of the estimates and homogeneity of trends in the study populations. INTERPRETATION: Changes in the classic risk factors seem to partly explain the variation in population trends in CHD. Residual variance is attributable to difficulties in measurement and analysis, including time lag, and to factors that were not included, such as medical interventions. The results support prevention policies based on the classic risk factors but suggest potential for prevention beyond these.

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PubMed2000

Estimation of contribution of changes in coronary care to improving survival, event rates, and coronary heart disease mortality across the WHO MONICA Project populations.

BACKGROUND: The revolution in coronary care in the mid-1980s to mid-1990s corresponded with monitoring of coronary heart disease (CHD) in 31 populations of the WHO MONICA Project. We studied the impact of this revolution on coronary endpoints. METHODS: Case fatality, coronary-event rates, and CHD mortality were monitored in men and women aged 35-64 years in two separate 3-4-year periods. In each period, we recorded percentage use of eight treatments: coronary-artery reperfusion before, thrombolytics during, and beta-blockers, antiplatelet drugs, and angiotensin-converting-enzyme (ACE) inhibitors before and during non-fatal myocardial infarction. Values were averaged to produce treatment scores. We correlated changes across populations, and regressed changes in coronary endpoints on changes in treatment scores. FINDINGS: Treatment changes correlated positively with each other but inversely with change in coronary endpoints. By regression, for the common average treatment change of 20, case fatality fell by 19% (95% CI 12-26) in men and 16% (5-27) in women; coronary-event rates fell by 25% (16-35) and 23% (7-39); and CHD mortality rates fell by 42% (31-53) and 34% (17-50). The regression model explained an estimated 61% and 41% of variance for men and women in trends for case fatality, 52% and 30% for coronary-event rates, and 72% and 56% for CHD mortality. INTERPRETATION: Changes in coronary care and secondary prevention were strongly linked with declining coronary endpoints. Scores and benefits followed a geographical east-to-west gradient. The apparent effects of the treatment might be exaggerated by other changes in economically successful populations, so their specificity needs further assessment.

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PubMed2000

Accuracy of the estimated prevalence of obesity from self reported height and weight in an adult Scottish population.

STUDY OBJECTIVE: To determine whether self reported heights and weights from Scottish adults can provide an accurate assessment of obesity prevalence in the population. DESIGN: Standardised clinic measurements of weight and height were compared against self reported values on a postal questionnaire in the fourth Scottish MONICA cross sectional study. SETTING: A sex and five year age band stratified random population sample drawn from general practitioner registers in north Glasgow in 1995. Response rate 63% for men and 62% for women. PARTICIPANTS: A total of 865 men and 971 women aged between 25 and 64 years. RESULTS: Men and women under-reported their weight by a mean (SD) of 0.63 (3.45) kg and 0.95 (2.64) kg respectively, and their height by a mean (SD) of 1.3 (2.50) cm and 1.7 (2.37) cm respectively. Estimated body mass index, BMI (kg/m2) varied from true (measured) BMI by +0.19 (1.40) for men and by +0.17 (1.34) for women. The only age/sex group in which BMI was under-estimated from self reports (mean 0.2) was the 55-64 year old women. Prediction equations that explained 90% (men) and 88% (women) of the difference between self reported and measured height included age and self reported weight. The equivalent prediction equations for weight explained 93% of the difference between self reported and measured weight for men and included smoking and diabetic status, while for women 96% of the variance was explained with no further variables being significant. Sensitivity and specificity for determining clinical obesity (BMI > or = 30) were 83% and 96% respectively for men, and 89% and 97% for women. CONCLUSIONS: This Scottish population was unique in the under-reporting of height as well as weight, which resulted in BMI estimates with low error. These data suggest that self reported weights and heights would be satisfactory for the monitoring of obesity prevalence in Scotland.

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PubMed2000

Plasma vitamin C and food choice in the third Glasgow MONICA population survey.

STUDY OBJECTIVE: To determine the contribution of different foods to the estimated intakes of vitamin C among those differing in plasma vitamin C levels, and thereby inform dietary strategies for correcting possible deficiency. DESIGN: Cross sectional random population survey. SETTING: North Glasgow, Scotland, 1992. PARTICIPANTS: 632 men and 635 women, aged 25 to 74 years, not taking vitamin supplements, who participated in the third MONICA study (population survey monitoring trends and determinants of cardiovascular disease). MEASUREMENTS AND MAIN RESULTS: Dietary and sociodemographic information was collected using a food frequency and lifestyle questionnaire. Plasma vitamin C was measured in non-fasted venous blood samples and subjects categorised by cut points of 11.4 and 22.7 micromol/l as being of low, marginal or optimal vitamin C status. Food sources of dietary vitamin C were identified for subjects in these categories. Plasma vitamin C concentrations were compared among groups classified according to intake of key foods. More men (26%) than women (14%) were in the low category for vitamin C status; as were a higher percentage of smokers and of those in the older age groups. Intake of vitamin C from potatoes and chips (fried potatoes) was uniform across categories; while the determinants of optimal versus low status were the intakes of citrus fruit, non-citrus fruit and fruit juice. Optimal status was achieved by a combined frequency of fruit, vegetables and/or fruit juice of three times a day or more except in older male smokers where a frequency greater than this was required even to reach a marginal plasma vitamin C level. CONCLUSION: Fruit, vegetables and/or fruit juice three or more times a day increases plasma vitamin C concentrations above the threshold for risk of deficiency.

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PubMed1999

Dietary antioxidant vitamins and fiber in the etiology of cardiovascular disease and all-causes mortality: results from the Scottish Heart Health Study.

In this paper, data obtained between 1984 and 1993 from 11,629 men and women as part of the Scottish Heart Health Study (Scotland, United Kingdom) were used to investigate the relation between antioxidant vitamin and fiber intakes and both incident coronary heart disease (CHD) (649 events) and all-causes mortality (591 deaths). All age-adjusted mean intakes tended to be higher in the group that experienced no event. For men, increased fiber intake was associated with decreased risk of CHD even after adjustment for a host of other major coronary risk factors; hazard ratios relative to the lowest quarter were 0.68, 0.70, and 0.64 by increasing quarter. This relation was also observed for mortality (hazard ratios of 0.62, 0.66, and 0.62). Evidence was found that higher intakes of the antioxidants were also beneficial, although the associations were weaker. For women, fiber was the only obviously influential dietary factor, with hazard ratios of 0.94, 0.60, and 0.56 for CHD and 1.25, 0.82, and 0.65 for mortality. These results suggest that the current public health drive to increase the consumption of foods rich in antioxidant vitamins and (particularly) fiber will impact on both CHD risk and the general health of the population.

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PubMed1999

Contribution of trends in survival and coronary-event rates to changes in coronary heart disease mortality: 10-year results from 37 WHO MONICA project populations. Monitoring trends and determinants in cardiovascular disease.

BACKGROUND: The WHO MONICA (monitoring trends and determinants in cardiovascular disease) Project monitored, from the early 1980s, trends over 10 years in coronary heart disease (CHD) across 37 populations in 21 countries. We aimed to validate trends in mortality, partitioning responsibility between changing coronary-event rates and changing survival. METHODS: Registers identified non-fatal definite myocardial infarction and definite, possible, or unclassifiable coronary deaths in men and women aged 35-64 years, followed up for 28 days in or out of hospital. We calculated rates from population denominators to estimate trends in age-standardised rates and case fatality (percentage of 28-day fatalities=[100-survival percentage]). FINDINGS: During 371 population-years, 166,000 events were registered. Official CHD mortality rates, based on death certification, fell (annual changes: men -4.0% [range -10.8 to 3.2]; women -4.0% [-12.7 to 3.0]). By MONICA criteria, CHD mortality rates were higher, but fell less (-2.7% [-8.0 to 4.2] and -2.1% [-8.5 to 4.1]). Changes in non-fatal rates were smaller (-2.1%, [-6.9 to 2.8] and -0.8% [-9.8 to 6.8]). MONICA coronary-event rates (fatal and non-fatal combined) fell more (-2.1% [-6.5 to 2.8] and -1.4% [-6.7 to 2.8]) than case fatality (-0.6% [-4.2 to 3.1] and -0.8% [-4.8 to 2.9]). Contribution to changing CHD mortality varied, but in populations in which mortality decreased, coronary-event rates contributed two thirds and case fatality one third. INTERPRETATION: Over the decade studied, the 37 populations in the WHO MONICA Project showed substantial contributions from changes in survival, but the major determinant of decline in CHD mortality is whatever drives changing coronary-event rates.

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PubMed1999

Associations of blood rheology and interleukin-6 with cardiovascular risk factors and prevalent cardiovascular disease.

Haemorheological variables (whole-blood, plasma and relative blood viscosity, haematocrit, red cell aggregation, white cell count and fibrinogen) were measured in 753 men and 821 women aged 25-74 years, and related to cardiovascular risk factors and prevalent cardiovascular disease (CVD). Men had higher levels than women of blood viscosity, haematocrit, corrected viscosity and relative viscosity. Post-menopausal women had higher levels than pre-menopausal women of blood viscosity, haematocrit, corrected blood viscosity, plasma viscosity and fibrinogen: each of these differences was completely or partly abolished by use of hormone replacement therapy. Serum total cholesterol, triglycerides, diastolic blood pressure, body mass index and smoking markers showed positive associations with most rheological variables, whereas HDL-cholesterol, plasma vitamin C and social class showed inverse associations. Rheological variables were associated with prevalent CVD after age-adjustment. However, after multiple risk factor adjustment only plasma viscosity and red cell aggregation showed significant (P<0.04) associations in both men and women (comparing top to bottom quarters). Plasma interleukin-6 (measured in a 25% subsample of 196 men and 221 women) correlated significantly with age, fibrinogen, white cell count, plasma and blood viscosity, current smoking, and (in men) with low serum vitamin C levels; but not with other major risk factors or with prevalent cardiovascular disease.

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PubMed1999

Coffee and tea consumption in the Scottish Heart Health Study follow up: conflicting relations with coronary risk factors, coronary disease, and all cause mortality.

STUDY OBJECTIVE: To relate habitual (cups per day) tea and coffee consumption to conventional coronary risk factors and subsequent risk of coronary heart disease and death. DESIGN: Cohort study. SETTING: Nationwide random population study. PARTICIPANTS: Over 11,000 men and women aged 40-59 who took part in the Scottish Heart Health Study lifestyle and risk factor survey in 1984-87. Participants were followed up to the end of 1993, an average of 7.7 years, for all cause mortality, coronary death, or any major coronary event (death, non-fatal infarction or coronary artery surgery). Cox's proportional hazards regression model was used to estimate the hazard in consumers of tea and coffee relative to the zero consumption group, both before and after correction for other factors. MAIN RESULTS: Coffee and tea consumption showed a strong inverse relation. For many conventional risk factors, coffee showed a weak, but beneficial, gradient with increasing consumption, whereas increasing tea consumption showed the reverse. Increasing coffee consumption was associated with beneficial effects for mortality and coronary morbidity, whereas tea showed the opposite. Adjusting for age and social class had some effect in reducing associations. Multiple adjustment for other risk factors removed the associations for tea and most of those for coffee although there was a residual benefit of coffee consumption in avoiding heart disease among men. CONCLUSIONS: The epidemiological differences shown in this study occurred despite the pharmacological similarities between tea and coffee. Either they differ more than is realised, or they identify contrasting associated lifestyle and health risks, for which this multiple adjustment was inadequate.

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PubMed1999

Does dietary potassium lower blood pressure and protect against coronary heart disease and death? Findings from the Scottish Heart Health Study?

We related 24-hour sodium and potassium excretion cross-sectionally to blood pressure and longitudinally to coronary events and deaths during follow-up in a representative sample of the Scottish population. A random sampling of men and women aged 40-59 in 1984 to 1987 produced 11,629 men and women who provided questionnaire results, examination and biochemical findings, and follow-up data, the majority of whom provided a 24-hour urine collection. The main outcome measures were blood pressure, myocardial infarction or coronary deaths during follow-up, and death from all causes. Risks of endpoints were calculated by fifths of the 24-hour sodium and potassium excretion. Blood pressure was very weakly related to sodium excretion and marginally better related to potassium, at least for systolic blood pressure in men, although age, body mass index, alcohol consumption, and pulse rate were better related than either electrolyte. Potassium excretion was very significantly related to risk of death from all causes, having a protective role, whereas its role in coronary events was weaker and that of sodium excretion weak and even paradoxical. These results are unifactorial, without correction other than for age and sex. Our findings need corroboration from elsewhere and more detailed analysis with more events from longer follow-up.

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PubMed1999

Self-reported smoking, cigarette yields and inhalation biochemistry related to the incidence of coronary heart disease: results from the Scottish Heart Health Study.

BACKGROUND: Smoking is a well-known risk factor for coronary heart disease (CHD). The components of tobacco that cause CHD have not yet been established; nor have the relative dangers of cigarettes of different strengths. METHODS: This is a cohort study of 2,849 men and 2,900 women with no symptoms of CHD at baseline in the Scottish Heart Health Study. RESULTS: In a 7.7 year follow-up, to 1993, there were 123 male and 49 female CHD events. After adjusting for age, cholesterol and blood pressure, men who smoke > or = 20 cigarettes per day have a relative hazard [95% confidence interval (CI)] of 1.93 (1.15-3.24) compared with non-smokers; for women the corresponding relative hazard is 3.81 (2.00-7.27). Biochemical measures (cotinine, thiocyanate and expired-air CO) are closely correlated with self-reported smoking (0.67 < or = r < or = 0.72), and have similar relationships with CHD. Amongst cigarette smokers, relative hazards (third to first tertile), for tar yield are 1.05 (0.54-2.07) for men and 4.00 (1.13-14.18) for women. Nicotine and CO yields give similar results. Hazard ratios associated with heavy smoking and strong cigarettes are thus much higher for women. CONCLUSION: Although smoking was found to have a detrimental effect, this study was unable to suggest a single major cause of CHD. The excess effects found in women compared with men could be due to differences in former smoking habits. Furthermore, risk differences for smoking are slightly greater for men, explained by the relatively low incidence of CHD amongst women.

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