Prevalence of ischaemic heart disease: the Caerphilly and Speedwell surveys

Association between egg consumption and cardiovascular disease events, diabetes and all-cause mortality

Purpose

The association between egg consumption and cardiovascular disease (CVD) or type 2 diabetes (T2D) remains controversial. We investigated the association between egg consumption and risk of CVD (primary outcome), T2D and mortality in the Caerphilly prospective cohort study (CAPS) and National Diet and Nutritional Survey (NDNS).

Methods

CAPS included 2512 men aged 45–59 years (1979–1983). Dietary intake, disease incidence and mortality were updated at 5-year intervals. NDNS included 754 adults aged 19–64 years from 2008 to 2012.

Results

Men free of CVD (n = 1781) were followed up for a mean of 22.8 years, egg consumption was not associated with new incidence of CVD (n = 715), mortality (n = 1028) or T2D (n = 120). When stroke (n = 248), MI (n = 477), heart failure (n = 201) were investigated separately, no associations between egg consumption and stroke and MI were identified, however, increased risk of stroke in subjects with T2D and/or impaired glucose tolerance (IGT, fasting plasma glucose ≥ 6.1 mmol/L), adjusted hazard ratios (95% CI) were 1.0 (reference), 1.09 (0.41, 2.88), 0.96 (0.37, 2.50), 1.39 (0.54, 3.56) and 2.87 (1.13, 7.27) for egg intake (n) of 0 ≤ n ≤ 1, 1 < n ≤ 2, 2 < n ≤ 3, 3 < n < 5, and n ≥ 5 eggs/wk, respectively (P = 0.01). In addition, cross-sectional analyses revealed that higher egg consumption was significantly associated with elevated fasting glucose in those with T2D and/or IGT (CAPS: baseline P = 0.02 and 5-year P = 0.04; NDNS: P = 0.05).

Conclusions

Higher egg consumption was associated with higher blood glucose in subjects with T2D and/or IGT. The increased incidence of stroke with higher egg consumption among T2D and/or IGT sub-group warrants further investigation.

Electronic supplementary material

The online version of this article (doi:10.1007/s00394-017-1566-0) contains supplementary material, which is available to authorized users.

Vitamin D intake and risk of CVD and all-cause mortality: evidence from the Caerphilly Prospective Cohort Study

Objective

Prospective data on the associations between vitamin D intake and risk of CVD and all-cause mortality are limited and inconclusive. The aim of the present study was to investigate the associations between vitamin D intake and CVD risk and all-cause mortality in the Caerphilly Prospective Cohort Study.

Design

The associations of vitamin D intake with CVD risk markers were examined cross-sectionally at baseline and longitudinally at 5-year, 10-year and >20-year follow-ups. In addition, the predictive value of vitamin D intake for CVD events and all-cause mortality after >20 years of follow-up was examined. Logistic regression and general linear regression were used for data analysis.

Setting

Participants in the UK.

Subjects

Men (n452) who were free from CVD and type 2 diabetes at recruitment.

Results

Higher vitamin D intake was associated with increased HDL cholesterol (P=0·003) and pulse pressure (P=0·04) and decreased total cholesterol:HDL cholesterol (P=0·008) cross-sectionally at baseline, but the associations were lost during follow-up. Furthermore, higher vitamin D intake was associated with decreased concentration of plasma TAG at baseline (P=0·01) and at the 5-year (P=0·01), but not the 10-year examination. After >20 years of follow-up, vitamin D was not associated with stroke (n72), myocardial infarctions (n142), heart failure (n43) or all-cause mortality (n281), but was positively associated with increased diastolic blood pressure (P=0·03).

Conclusions

The study supports associations of higher vitamin D intake with lower fasting plasma TAG and higher diastolic blood pressure.

Milk and dairy consumption, diabetes and the metabolic syndrome: the Caerphilly prospective study

OBJECTIVES

To report a negative association between milk or dairy consumption and the metabolic syndrome and to examine associations within the Caerphilly cohort.

SETTING

A representative sample of men aged 45-59 years in Caerphilly, UK. PARTICIPANTS AND DATA: Data on fasting blood glucose and plasma insulin, fasting plasma triglycerides and high-density lipoprotein cholesterol, body mass index, and blood pressure were used to define the metabolic syndrome in terms of levels of two or more variates within the top 10%. The clinical importance of the syndrome was assessed from 20-year incidence of diabetes, vascular events and deaths. The relationships between the syndrome and the consumption of milk and dairy products was examined using data from both a semiquantitative food frequence questionnaire, and from a 7-day weighed intake record which had been kept by a 1:3 subsample of the men.

MAIN RESULTS

There were 2,375 men without diabetes in the cohort. The prevalence of the metabolic syndrome was 15%. Men with the syndrome had significantly increased risks of a subsequent ischaemic heart disease event, death or diabetes. Negative relationships were shown between both the consumption of milk and dairy produce, and the syndrome. Adjusted odds ratio in men who regularly drank a pint of milk or more daily was 0.38 (0.18 to 0.78) and that for dairy food consumption was 0.44 (0.21 to 0.91). Milk intake showed no significant trend with incident diabetes.

CONCLUSIONS

The consumption of milk and dairy products is associated with a markedly reduced prevalence of the metabolic syndrome, and these items therefore fit well into a healthy eating pattern.

Under-diagnosis of common chronic diseases: prevalence and impact on human health

AIMS

The disability-adjusted life years (DALY) and its components, namely the years lived with disability and the years of life lost, are measures of the impact of disease on human health. Our impression was that several common chronic diseases responsible for many DALYs are frequently under-diagnosed.

METHODS

We attempted to summarise data regarding the under-diagnosis of common chronic diseases of the developed world, which are associated with considerable mortality and/or disability. We searched PubMed and Current Contents to identify relevant studies (1980-2005). Two reviewers extracted data concerning DALYs and prevalence of under-diagnosis of common chronic diseases.

RESULTS

Studies regarding the first 15 diseases (or group of diseases) based on DALYs were reviewed. The under-diagnosis of common chronic diseases in the developed world ranges from about 20% for dementia and cirrhosis to 90% for depression and osteoarthritis. The delay in the prompt diagnosis and initiation of treatment is associated with increased morbidity and mortality for most of the reviewed diseases.

CONCLUSION

The available evidence suggests that the prevalence of under-diagnosis of common chronic diseases is considerable. Physicians should be aware of the prevalence of under-diagnosis of chronic diseases and its impact on human health.

Sleep disturbance, stroke, and heart disease events: evidence from the Caerphilly cohort

OBJECTIVE

To test the hypothesis that sleep disorders are relevant to the risk of ischaemic stroke and ischaemic heart disease events in older men.

DESIGN

A cohort study.

SETTING

The Caerphilly cohort, a representative population sample of older men in South Wales, UK.

PARTICIPANTS

1986 men aged 55-69 years completed a questionnaire on sleep patterns with help from their partners. This asked about symptoms of disturbed sleep: insomnia, snoring, restless legs, obstructive sleep apnoea, and about daytime sleepiness. During the following 10 years 107 men experienced an ischaemic stroke and 213 had an ischaemic heart disease event.

MAIN RESULTS

Up to one third of the men reported at least one symptom suggestive of sleep disturbance, and one third reported daytime sleepiness. Compared with men who reported no such symptoms, the adjusted relative odds of an ischaemic stroke were significantly increased in men with any sleep disturbance, the strongest association being with sleep apnoea (relative odds 1.97; 1.26 to 3.09). The association with daytime sleepiness was not significant for stroke. Relations with ischaemic heart disease events were all raised in men with symptoms of sleep disturbance, but none was significant, other than daytime sleepiness (relative odds: 1.41; 1.04 to 1.92). There were no significant relations with blood pressure.

CONCLUSION

The risk of an ischaemic stroke is increased in men whose sleep is frequently disturbed, and daytime sleepiness is associated with a significant increase in ischaemic heart disease events.

Ethnic disparities in cardiovascular risk factors and coronary disease prevalence among individuals with chronic kidney disease: findings from the Third National Health and Nutrition Examination Survey

Differences in coronary disease have been reported among ethnic minorities in the US population. Whether these persist in patients with chronic kidney disease is unknown. The prevalence of myocardial infarction (MI) and angina was compared by race and GFR in the Third National Health and Nutrition Examination Survey using the Modification of Diet in Renal Disease Study equation. Age-gender standardized estimates were computed for each GFR category (>or=90, 60 to 89, and <60 ml/min per 1.73 m2), and odds ratios were compared using weighted multivariable logistic regression for each race. The age-gender standardized prevalence of MI was 3.0, 3.1, and 4.9% in white individuals; 2.8, 3.8, and 9.9% in black individuals; and 1.9, 2.9, and 3.8% in Mexican-American individuals in each category: >or=90, 60 to 89, and <60 ml/min, respectively. Compared with the referent (Mexican-American; GFR>or=90 ml/min; odds ratio 1.00), Mexican-American individuals with GFR of 60 to 89 and <60 ml/min had more than four and nine times the odds for MI; black individuals at successively lower GFR levels had 1.6, 6.1, and 16.3 times the odds for MI, whereas white individuals had 1.9, 4.7, and 20.2 times that of the referent, respectively. After adjustment for traditional risk factors, the inverse association of GFR with MI was substantially attenuated in black and white individuals and completely abolished in Mexican-American individuals. The burden of coronary disease is lower in Mexican-American than in white or black individuals with reduced kidney function even accounting for differences in traditional risk factors.

Prevalence, incidence, primary care burden and medical treatment of angina in Scotland: age, sex and socioeconomic disparities: a population-based study

OBJECTIVE

To examine the epidemiology, primary care burden and treatment of angina in Scotland.

DESIGN

Cross-sectional data from primary care practices participating in the Scottish continuous morbidity recording scheme between 1 April 2001 and 31 March 2002.

SETTING

55 primary care practices (362 155 patients).

PARTICIPANTS

9508 patients with angina.

RESULTS

The prevalence of angina in Scotland was 28/1000 in men and 25/1000 in women (p < 0.05) and increased with age. The prevalence of angina also increased with increasing socioeconomic deprivation from 18/1000 in the least deprived category to 31/1000 in the most deprived group (p < 0.001 for trend). The incidence of angina was higher in men (1.8/1000) than in women (1.4/1000) (p = 0.004) and increased with increasing age and socioeconomic deprivation. Socioeconomically deprived patients (0.48 contacts/patient among the most deprived) were less likely than affluent patients (0.58 contacts/patient among the least deprived) to see their general practitioner on an ongoing basis p = 0.006 for trend). Among men, 52% were prescribed beta blockers, 44% calcium channel blockers, 72% aspirin, 54% statins and 36% angiotensin converting enzyme inhibitors or angiotensin receptor blockers. The corresponding prescription rates for women were 46% (p < 0.001), 41% (p = 0.02), 69% (p < 0.001), 45% (p < 0.001) and 30% (p < 0.001). Among patients < 75 years old 52% were prescribed a beta blocker and 58% a statin. The corresponding figures for patients >or= 75 years were 42% (p < 0.001) and 31% (p < 0.001).

CONCLUSIONS

Angina is a common condition, more so in men than in women. Socioeconomically deprived patients are more likely to have angina but are less likely to consult their general practitioner. Guideline-recommended treatments for angina are underused in women and older patients. These suboptimal practice patterns, which are worst in older women, are of particular concern, as in Scotland more women (and particularly older women) than men have angina.

Milk consumption, stroke, and heart attack risk: evidence from the Caerphilly cohort of older men

OBJECTIVE

To examine associations between milk consumption and incident heart disease and stroke.

DESIGN

A representative population sample of men was asked to weigh and record their food intake for seven days. The total consumption of milk was obtained from these records. Details of all deaths and vascular events were collected during the following 20 years. Incident ischaemic strokes and heart disease events were diagnosed by standard criteria.

SETTING

The Caerphilly cohort, a representative population sample of men in South Wales, aged 45-59 when first seen in 1979-83.

PARTICIPANTS

A representative 3:10 subsample of the men in the cohort.

MAIN RESULTS

665 men (87% of those approached) returned satisfactory seven day diet diaries. After adjustment, the relative odds of an event in the men whose milk consumption was the median or higher, relative to those with lower intakes of milk, were 0.52 (0.27 to 0.99) for an ischaemic stroke and 0.88 (0.56 to 1.40) for an ischaemic heart disease event. Deaths from all causes were similar in the two milk consumption groups (relative odds 1.08; 0.74 to 1.58).

CONCLUSIONS

These results give no convincing evidence of an increased risk of vascular disease from milk drinking. Rather, the subjects who drank more than the median amount of milk had a reduced risk of an ischaemic stroke, and possibly a reduced risk of an ischaemic heart disease event. These conclusions are in agreement with the results of a previously reported overview of 10 large, long term cohort studies based on food frequency intake records.

Milk drinking, ischaemic heart disease and ischaemic stroke I. Evidence from the Caerphilly cohort

OBJECTIVE

To test the hypothesis that milk drinking increases the risk of ischaemic heart disease (IHD) and ischaemic stroke in a prospective study.

DESIGN

In the Caerphilly Cohort Study dietary data, including milk consumption, were collected by a semiquantitative food frequency questionnaire in 1979-1983. The cohort has been followed for 20-24 y and incident IHD and stroke events identified.

SUBJECTS

A representative population sample in South Wales, of 2512 men, aged 45-59 y at recruitment.

MAIN OUTCOME MEASURES

In total, 493 men had an IHD event and 185 an ischaemic stroke during follow-up.

RESULTS

After adjustment, the hazard ratio in men with a milk consumption of one pint (0.57 l) or more per day, relative to men who stated that they consumed no milk, is 0.71 (0.40-1.26) for IHD and 0.66 (0.24-1.81) for ischaemic stroke. At baseline, 606 men had had clinical or ECG evidence of vascular disease, and in these the vascular risk was even lower (0.37; 0.15-0.90). The hazard ratio for IHD and ischaemic stroke combined is 0.64 (0.39-1.06) in all men and 0.37 (0.15-0.90) in those who had had a prior vascular event.

CONCLUSION

The data provide no convincing evidence that milk consumption is associated with an increase in vascular disease risk. Evidence from an overview of all published cohort studies on this topic should be informative.

SPONSORSHIP

: The Medical Research Council, the University of Wales College of Medicine and Bristol University. Current support is from the Food Standards Agency.

Resonance-thrombography indices of the haemostatic process in relation to risk of incident coronary heart disease: 9 years follow-up in the Caerphilly Prospective Heart Disease Study

Global assays, such as resonance-thrombography (RTG), which measure the interaction between platelets, coagulation and fibrinolysis have been used as summary measures of risk for over two decades but have not been evaluated in epidemiological studies. We examined whether RTG indices are risk indicators for incident coronary heart disease (CHD). RTG indices, related haematological variables and other risk factors were measured between 1984 and 1988 in a cohort of 2398 British men. Reaction time (r) and amplitude of fibrin leg (AF) were associated with lifestyle risk factors. During 9 years of follow-up, 282 (12%) men developed a major new CHD event, as classified by World Health Organization criteria. On adjustment for age, only r and AF measured at baseline were related to risk of incident CHD. On multivariate adjustment in a multiple logistic regression model that included age, diastolic blood pressure, body mass index, total and high-density lipoprotein cholesterol, lifestyle risk factors and use of prescribed medicine, these associations weakened but remained significant. Additional adjustment for fibrinogen, viscosity, white cell count and fibrin d-dimer either reduced these associations to non-significance (AF) or to borderline significance (r).

Health status as a potential effect modifier of the relation between noise annoyance and incidence of ischaemic heart disease

AIMS

Traffic noise is a psychosocial stressor. Epidemiological studies suggest chronic noise stress to be a risk factor for cardiovascular disorders.

METHODS

In a prospective cohort study, the association between annoyance and disturbances due to road traffic noise and the incidence of ischaemic heart disease (IHD) was studied in 3950 middle aged men.

RESULTS

Depending on the questionnaire item, non-significant odds ratios for IHD incidence ranging from 0.9 to 1.4 were found for the highly noise annoyed/disturbed subjects when compared with the less annoyed/disturbed subjects, over the six year follow up period. However, this relation was strongly modified by the prevalence of pre-existing chronic diseases. In subjects free of any chronic disease at the beginning of the follow up, significant odds ratios between 1.7 and 3.0 were seen. In the subgroup with chronic diseases no such noise effects were seen. This surprising result of no effect in the group of people with a potential risk, due to pre-existing health problems, may be because of the dilution of the true effect due to recall bias.

CONCLUSIONS

Annoyance and disturbance due to road traffic noise is associated with a higher incidence of IHD. Prevalence of disease can be an important effect modifier of the relation between noise annoyance and health outcomes.

The performance of the Rose angina questionnaire in South Asian and European origin populations: a comparative study in Newcastle, UK

BACKGROUND

The Rose angina questionnaire has been extensively used in different cultural settings, but may not perform consistently in different ethnic groups. We set out to assess the performance of the Rose angina questionnaire in UK South Asians compared with Europeans.

METHODS

Data on major ECG abnormalities, possible or definite Rose questionnaire angina and diagnosed angina were collected from an age- and sex-stratified random sample of 1509 adults from European, Indian, Pakistani and Bangladeshi ethnic groups.

RESULTS

The ECG abnormalities were commoner in South Asians than Europeans (6% versus 2% in men). The prevalence in both South Asian and European men of possible Rose angina and diagnosed angina was 18% and 8%, respectively, but definite Rose angina was less common in South Asians (3% versus 6%). Definite Rose angina showed lower sensitivity for other measures in South Asians than in Europeans: sensitivity for a doctor's diagnosis was 21% in South Asian and 37% in European men. For possible Rose angina, the corresponding figures were 81% and 84%. Similar patterns were seen in women.

CONCLUSIONS

The performance of the Rose angina questionnaire was sufficiently inconsistent to warrant further work to achieve greater cross-cultural validity. Possible Rose angina performed more consistently across ethnic groups than definite Rose angina and pending further validation studies may be the most appropriate form to use.

C-reactive protein, fibrin D-dimer, and incident ischemic heart disease in the Speedwell study: are inflammation and fibrin turnover linked in pathogenesis?

Plasma levels of C-reactive protein (CRP, a marker of the reactant plasma protein component of the inflammatory response) and of fibrin D-dimer (a marker of cross-linked fibrin turnover) have each been associated in recent studies with the risk of future ischemic heart disease (IHD). Previous experimental studies have shown that fibrin degradation products, including D-dimer, have effects on inflammatory processes and acute-phase protein responses. In the Speedwell Prospective Study, we therefore measured CRP and D-dimer levels in stored plasma samples from 1690 men aged 49 to 67 years who were followed-up for incident IHD for an average of 75+/-4 months (mean+/-SD) and studied their associations with each other, with baseline and incident IHD, and with IHD risk factors. CRP and D-dimer levels were each associated with age, plasma fibrinogen, smoking habit, and baseline evidence of IHD. CRP was associated with D-dimer (r=0.21, P<0.00001). On univariate analyses, both CRP and D-dimer were associated with incident IHD. The incidence of IHD increased with CRP independently of the level of D-dimer (P=0.0002) and also increased with D-dimer independently of the level of CRP (P=0.048). In multivariate analyses, inclusion of D-dimer and conventional risk factors reduced the strength of the association between CRP and incident IHD; likewise, inclusion of CRP and conventional risk factors reduced the strength of the association between D-dimer and incident IHD. We conclude that although these respective markers of inflammation and fibrin turnover show modest association with each other in middle-aged men, they may have additive associations with risk of incident IHD. Further larger studies are required to test this hypothesis.

Declining prevalence of angina pectoris in middle-aged men and women. A population-based study within the Northern Sweden MONICA Project. Multinational Monitoring of Trends and Cardiovascular Disease

OBJECTIVES

To describe trends in the prevalence of angina pectoris in northern Sweden, between 1986 and 1994.

DESIGN

Cross-sectional population studies.

SETTING

Northern Sweden MONICA Project in Norrbotten and Västerbotten counties, Sweden.

SUBJECTS

Randomly selected men and women in the age group 35-64 years, total of 2459 men and women.

MAIN OUTCOME MEASURES

Comparison of the prevalence of angina pectoris in 1986 and 1994 as measured by the Rose questionnaire.

RESULTS

The proportion with a history of myocardial infarction decreased amongst the participants from 4.6% to 2.0% (P < 0.001) between 1986 and 1994. The prevalence of angina pectoris in men was essentially unchanged (3.4% in 1986 to 3.1% in 1994 (chi2 = 0.02; P = 0.87), whereas it declined significantly in women from 5. 9% to 2.8% (chi2 = 6.32; P = 0.01). In both men and women, the highest prevalence of Rose-positive persons was found in the oldest age group. In 1986 the Rose-positive subgroup had a significantly higher proportion with high cholesterol (>/=6.5 mmol L-1) as compared with the Rose-negative subgroup, 64% vs. 48% (chi2 = 5.04; P = 0.02). In both surveys high blood pressure was more common in the Rose-positive group (1986: chi2 = 13.2; P < 0.001 and 1994: chi2 = 9.8; P = 0.002).

CONCLUSIONS

In women, but not in men, the prevalence of angina pectoris decreased significantly between 1986 and 1994. During the same time period the proportion of people with high cholesterol decreased in northern Sweden. In both surveys, individuals with angina pectoris had more frequent hypertension.

Natural history of myocardial infarction and angina pectoris in a general population sample of middle-aged men: a 16-year follow-up of the Primary Prevention Study, Göteborg, Sweden

OBJECTIVES

Although many studies have described prognosis in patients with coronary heart disease (CHD), few have compared outcome in men with clinical evidence of CHD with healthy men from the general population over an extended follow-up. This study aimed to compare long-term prognosis in men with a history of myocardial infarction (MI) and in men with angina pectoris (AP) without MI, with men without clinical signs of CHD.

DESIGN

Longitudinal general population study.

SETTING

City of Göteborg, Sweden.

SUBJECTS

From a general population sample, 195 men who had survived an MI for 0-19 years (median 3 years) and 314 men with AP but no MI (uncomplicated AP) at baseline in 1974-77 were identified and compared with 6591 men without clinical coronary disease. All were aged 51-59 years. Incident non-fatal and fatal cases occurring until the beginning of 1983 were also followed (n = 317).

MAIN OUTCOME MEASURES

Death from CHD, from other causes and from all causes during a follow-up of at least 16 years.

RESULTS

Overall survival was 72% amongst men without coronary disease, 53% amongst men with uncomplicated AP and 34% amongst men with past MI at baseline. In survivors of MI the risk-factor-adjusted relative risk (RR) of coronary death during follow-up was 6.67 (95% confidence interval (CI) 5.29-8.39), of dying from non-cardiovascular causes 1.35 (0.96-1.91), and of dying from any cause 3.20 (2.67-3.83). During the first 4 years after the baseline examination, the adjusted RR of CHD death was 15.96 (10. 29-24.74), and of dying from any cause 5.22 (3.68-7.41). During the last 4 years of follow-up, relative risk was still 5.87 (3.44-10.01) for CHD death and 2.93 (2.05-4.18) for death from any cause. In men with uncomplicated AP, the adjusted relative risk of CHD death during the first 4 years was 4.05 (2.27-7.22) and 3.23 (2.10-4.96) during the last 4-year period. After the first year, the incident MI cases had the same average annual mortality (about 5%) as the prevalent cases.

CONCLUSIONS

In survivors of MI, mortality risk remained high even after an extended follow-up. Men with angina had a better prognosis, but still a compromised survival compared with the general population.

A DNA variant at the angiotensin-converting enzyme gene locus associates with coronary artery disease in the Caerphilly Heart Study

BACKGROUND

We analyzed an insertion/deletion (I/D) polymorphism of the angiotensin I-converting enzyme (ACE) gene in 1226 subjects from the Caerphilly Prospective Heart Disease Study. Amplification of genomic DNA using the polymerase chain reaction yielded the genotypes II, ID, and DD. Distribution of the polymorphism was analyzed among the whole group and within subgroups (specified following multiple risk factor analysis) for coronary artery disease (CAD) and against multiple risk factors.

METHODS AND RESULTS

Allele frequencies were I = 0.413 and D = 0.587. No association was observed between the polymorphism and CAD in the whole group. Among subjects defined at lower risk of CAD by total cholesterol/HDL cholesterol (TC/HDL) ratios, we found significant associations of the DD genotype with CAD (P < .0053, n = 586 for TC/HDL < 5.654 [median] and P < .009, n = 385 for TC/HDL < 5.0 [clinical threshold]). On further exclusion of subjects with blood pressures > or = 140/90 or on hypotensive medications, the DD genotype still associated with CAD (P < .07, n = 210, TC/HDL < 5.654 and P < .016, n = 135, TC/HDL < 5.0). Further stratification of risk incorporating other risk factors, except body mass index, did not alter or enhance this association. Although similar association was observed when risk was specified by using HDL and apo B levels instead of TC/HDL, this association was lost when body mass index was included in the low-risk stratification.

CONCLUSIONS

The DD genotype is a linkage marker for an etiologic mutation at or near the ACE gene that may confer risk of CAD detectable in subjects previously unidentifiable with "classic" risk factors. However, this risk may be quantitatively small among the general male population.

Prevalence of coronary heart disease in Turkish adults

The prevalence of coronary heart disease was determined by a conducted survey in a random sample of 3689 subjects 20 years of age or older in 59 communities representing the Turkish adult population. Interview with a questionnaire, physical examination of the cardiovascular system and recording of a 12-lead ECG were performed. The latter was coded according to the Minnesota code. Expressed in age-adjusted rates (for 35-64 years), prevalence rates per 100 men were as follows: typical angina 3.7, atypical angina 0.9, electrocardiographic evidence of myocardial infarction and/or ischemia 3.7, any of the stated findings suggesting coronary heart disease 8. Women had a substantially higher rate of atypical angina, positive ECG findings and of any of the stated manifestations for coronary heart disease, whereas they had a significantly lower rate of Q/QS patterns as well as of a history of myocardial infarction. Based on a probability-related point score, age-adjusted clinical coronary heart disease was estimated to prevail in 5.8% of men and 5% of women (P > 0.4) in the sample of the Turkish population. The respective rates in urban residents was 6% and in rural resident 4.8%. Among participants diagnosed coronary heart disease, 63% presented the form of angina without infarction, 27% had evidence of myocardial infarction, 7% 'silent myocardial ischemia' and 3% cardiac failure alone.

Diet and incident ischaemic heart disease: the Caerphilly Study

The Caerphilly Prospective Ischaemic Heart Disease (IHD) Study is based on a sample of 2512 men aged 45-59 years when first seen. Nutrient intakes, estimated using a self-administered semi-quantitative food frequency questionnaire, are available for 2423 men (96%). Amongst these, 148 major IHD events occurred during the first 5 years of follow-up. Associations were examined between these events and baseline diet. Incident IHD (new events) was negatively associated with total energy intake: men who went on to experience an IHD event had consumed 560 kJ (134 kcal)/d (6%) less at baseline than men who experienced no event (P = 0.01). The relative odds of an IHD event was 1.5 among men in the lowest fifth of energy intake, compared with 1.3, 1.2, 0.9 and 1.0 respectively for the other four fifths (P < 0.05). The difference in energy intake was reflected in lower intakes of every nutrient examined. When expressed as a percentage of total energy, mean intakes of men who experienced an IHD event were virtually identical to those of men who did not. There was some evidence suggesting a positive association between total fat intake and IHD risk, but the trend was not consistent and not statistically significant. There was no association for animal fat. Alcohol consumption was negatively associated with subsequent IHD, but only in men who already had evidence of IHD at baseline (P < 0.05). Dietary fibre, particularly from fruit and vegetables, was 7% lower in men who had an incident IHD event (P < 0.05), but the difference was not independent of total energy. There was a trend of increasing IHD risk with decreasing vitamin C intake, the relative odds of an IHD event being 1.6 among men in the lowest one-fifth of the vitamin C distribution, but this was not statistically significant.

The appropriateness of the use of cardiovascular procedures. British versus U.S. perspectives

To determine whether patients are less likely to receive an inappropriate procedure in countries that devote fewer resources to health care than does the United States, we studied how appropriately coronary angiography and coronary artery bypass surgery were performed in the Trent region of the United Kingdom. The medical records of 320 patients who underwent coronary angiography and 319 who underwent coronary artery bypass surgery in 1987 and 1988 were randomly selected for review. Despite the United Kingdom's more limited use of coronary angiography and coronary artery bypass surgery, a substantial proportion were still performed for less than appropriate reasons, by both U.S. and U.K. criteria. Merely reducing the rate of use of these procedures will not be sufficient to eliminate such inappropriate use.

Association of early-onset coronary heart disease in South Asian men with glucose intolerance and hyperinsulinemia

BACKGROUND

Rates of coronary heart disease are higher in South Asians (Indians, Pakistanis, and Bangladeshis) settled overseas than in other ethnic groups. We tested the hypothesis that this excess risk results from metabolic disturbances associated with insulin resistance.

METHODS AND RESULTS

There were 1,421 South Asian men and 1,515 European men aged 40-69 years in London examined in the Southall Study. Prevalence of ischemic ECG abnormalities was higher in South Asians than in Europeans (17% versus 12%, p < 0.001), with an excess of major Q waves (Minnesota codes 1-1 or 1-2) in younger South Asian men (p = 0.01 for the age-ethnicity interaction). Major Q waves were strongly associated with glucose intolerance and hyperinsulinemia in younger South Asians; these factors accounted statistically for 73% of major Q waves in those aged 40-54 years. Age-standardized prevalence of a positive history of coronary heart disease was similar in South Asians and Europeans (8.5% versus 8.2%, NS), and positive history without Q waves was not associated with glucose intolerance or hyperinsulinemia in South Asians. Smoking rates and average plasma cholesterol were lower in South Asians than in Europeans; in a logistic model controlling for smoking and cholesterol, the odds ratio for major Q waves in South Asians compared with Europeans was 2.4 (95% CI, 1.5-3.8). Adjusting for glucose intolerance and hyperinsulinemia reduced this ratio to 1.5 (95% CI, 0.9-2.5).

CONCLUSIONS

These results are consistent with the hypothesis that insulin resistance underlies the high coronary risk in South Asian people and strengthen the evidence for a fundamental role of this metabolic pattern in the etiology of coronary heart disease.

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.

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.

Ischemic heart disease and platelet aggregation. The Caerphilly Collaborative Heart Disease Study

The Caerphilly Collaborative Heart Disease Study is based on a large cohort of men (2,398) aged 49-66 years at the time of study. Platelet aggregation induced by collagen, thrombin, and ADP was measured in fasting blood samples and was related to prevalent angina, past myocardial infarction, and electrocardiographic evidence of ischemic heart disease. A number of subjects had taken aspirin, other nonsteroidal anti-inflammatory drugs, or other drugs affecting platelet aggregation 7 days before blood sample collection; after the exclusion of these subjects, data were available for 1,811 men. No relations were demonstrated with angina, but significant relations were shown between past myocardial infarctions and electrocardiographic evidence of ischemia and ADP-induced aggregation (both primary and secondary) and between electrocardiographic evidence of ischemia and thrombin-induced aggregation. The strongest relation indicated more than a twofold increase in the odds of a past myocardial infarction in subjects of the highest fifth of ADP-induced primary platelet aggregation compared with the lowest fifth. No significant relations were detected with collagen-induced aggregation. Accounting for a number of possible confounding factors had a relatively small impact on the relations between platelet aggregation and ischemic heart disease. Other evidence, including the well-established effect of aspirin on reducing the incidence of ischemic heart disease, indicates that the relations we describe are unlikely to be simply an effect of IHD on platelets.

Whole blood impedance platelet aggregometry and ischemic heart disease. The Caerphilly Collaborative Heart Disease Study

The Caerphilly Collaborative Heart Disease Study is based on a large cohort of men who were ages 49 to 64 years at the time of the study. We report the results for platelet aggregation measured in whole blood from a subsample of 308 men. The index of sensitivity used was the minimum concentration of adenosine diphosphate that produced a defined degree of impedance change in the Chronolog 560 aggregometer. There was a marked association between aggregation and prevalent ischemic heart disease (IHD). The odds ratios and 95% confidence intervals (CI) for prevalent IHD in men with the most sensitive platelets compared with those with the least sensitive platelets were 3.6 (95% Cl: 1.1 to 12.2) for angina; 7.3 (95% Cl: 2.0 to 24.3) for previous myocardial infarction (MI); and 2.7 (95% Cl: 1.0 to 7.6) for electrocardiogram evidence of ischemia. The confidence limits for these odds ratios are large because of the small sample size, but the estimates of odds ratio are relatively large compared to similar relationships between the traditional risk factors of serum cholesterol, blood pressure, smoking, and prevalent IHD (1.5 to 2.5). A number of factors that might confound the relationships between platelets and IHD were examined, but the associations remained statistically significant when these were taken into account.

Prevalence of coronary heart disease in Scotland: Scottish Heart Health Study

Data from 10,359 men and women aged 40-59 years from 22 districts in the Scottish Heart Health Study were used to describe the prevalence rates of coronary heart disease in Scotland in 1984-1986 and their relation to the geographical variation in mortality in these districts. Prevalence was measured by previous history, Rose chest pain questionnaire, and the Minnesota code of a 12 lead resting electrocardiogram. The prevalence of coronary heart disease in Scotland was high compared with studies from other countries that used the same standardised methods. A history of angina was more common in men (5.5%) than in women (3.9%), though in response to the Rose questionnaire 8.5% of women and 6.3% of men reported chest pain. A history of myocardial infarction was three times more common in men than women, as was a Q/QS pattern on the electrocardiogram. There were significant correlations between the different measures of coronary prevalence. District measures of angina correlated well with mortality from coronary heart disease, and these correlations tended to be stronger in women than in men. There was no significant correlation between mortality from coronary heart disease and measures of myocardial infarction. The study provides data on the prevalence of coronary heart disease in men and women that are valuable for the planning of cardiological services.

Prevalence of cardiovascular disease and diabetes mellitus in residents of Rochester, Minnesota

To determine the prevalence of cardiac disorders as risk factors for stroke, we conducted a survey in 1986 in a stratified random sample of the population of Rochester, Minnesota, 35 years of age or older. The medical records of the 2,122 subjects in the sample were retrieved with use of the Rochester Epidemiology Project medical records linkage system. The data were used to estimate (1) the reliability of self-reported information about cardiac and cerebrovascular disorders and (2) the age- and sex-specific prevalence of diabetes mellitus and various cardiac and cerebrovascular conditions. The estimated prevalence for selected risk factors in the population 35 years of age or older was 5.8% for diabetes mellitus, 3.3% for myocardial infarction, 1.2% for mitral valve disease, 4.2% for left ventricular hypertrophy, and 2.8% for atrial fibrillation or flutter. These data can be used to estimate resources required for evaluation and management of the disorders. When the prevalence and the relative risk for stroke are known for a particular cardiac disorder, the proportion of stroke attributable to that disorder can be estimated.

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.