Ankle brachial index combined with Framingham Risk Score to predict cardiovascular events and mortality: a meta-analysis.

CONTEXT: Prediction models to identify healthy individuals at high risk of cardiovascular disease have limited accuracy. A low ankle brachial index (ABI) is an indicator of atherosclerosis and has the potential to improve prediction. OBJECTIVE: To determine if the ABI provides information on the risk of cardiovascular events and mortality independently of the Framingham risk score (FRS) and can improve risk prediction. DATA SOURCES: Relevant studies were identified. A search of MEDLINE (1950 to February 2008) and EMBASE (1980 to February 2008) was conducted using common text words for the term ankle brachial index combined with text words and Medical Subject Headings to capture prospective cohort designs. Review of reference lists and conference proceedings, and correspondence with experts was conducted to identify additional published and unpublished studies. STUDY SELECTION: Studies were included if participants were derived from a general population, ABI was measured at baseline, and individuals were followed up to detect total and cardiovascular mortality. DATA EXTRACTION: Prespecified data on individuals in each selected study were extracted into a combined data set and an individual participant data meta-analysis was conducted on individuals who had no previous history of coronary heart disease. RESULTS: Sixteen population cohort studies fulfilling the inclusion criteria were included. During 480,325 person-years of follow-up of 24,955 men and 23,339 women, the risk of death by ABI had a reverse J-shaped distribution with a normal (low risk) ABI of 1.11 to 1.40. The 10-year cardiovascular mortality in men with a low ABI (< or = 0.90) was 18.7% (95% confidence interval [CI], 13.3%-24.1%) and with normal ABI (1.11-1.40) was 4.4% (95% CI, 3.2%-5.7%) (hazard ratio [HR], 4.2; 95% CI, 3.3-5.4). Corresponding mortalities in women were 12.6% (95% CI, 6.2%-19.0%) and 4.1% (95% CI, 2.2%-6.1%) (HR, 3.5; 95% CI, 2.4-5.1). The HRs remained elevated after adjusting for FRS (2.9 [95% CI, 2.3-3.7] for men vs 3.0 [95% CI, 2.0-4.4] for women). A low ABI (< or = 0.90) was associated with approximately twice the 10-year total mortality, cardiovascular mortality, and major coronary event rate compared with the overall rate in each FRS category. Inclusion of the ABI in cardiovascular risk stratification using the FRS would result in reclassification of the risk category and modification of treatment recommendations in approximately 19% of men and 36% of women. CONCLUSION: Measurement of the ABI may improve the accuracy of cardiovascular risk prediction beyond the FRS.

Parental history of premature coronary heart disease mortality and signs of ischemia on the resting electrocardiogram.

OBJECTIVES: Here we explore the association between a family history of premature coronary heart disease (CHD) death and ischemic electrocardiogram (ECG) findings in the offspring. BACKGROUND: In the general population, signs of ischemia are found on the resting ECG in about 10% of middle-aged men and women. Their independent predictive value for CHD morbidity and mortality has been shown in several studies. METHODS: Our results are based on cross-sectional data from three large epidemiological studies performed in Belgium during the past two decades: the Belgian Heart Disease Prevention Project (n = 8,145), the Belgian Interuniversity Research on Nutrition and Health survey (n = 7,625) and the MONICA project (n = 3,193). A parental history of fatal CHD was considered premature if the father died from CHD before age 60 or the mother before age 70. Ischemic ECG findings were defined according to Minnesota Code criteria I(1-3), IV(1-3), V(1-3) or VII1. RESULTS: Subjects with a parental history of premature CHD death were found to have experienced significantly more frequently symptomatic CHD. After exclusion of symptomatic individuals, no major differences in lifestyle-related risk factors were found between the groups with and without a parental history of premature fatal CHD. After multivariate adjustment for age, smoking, body mass index and sex, the odds ratios (and 95% confidence interval [CI]) for ECG ischemia associated with a positive parental history of premature death were 1.42 (1.10-1.82), 1.47 (1.16-1.88) and 1.37 (0.78-2.41) in the three studies. Additional adjustment for systolic blood pressure, total cholesterol and, if available, lifestyle-related factors did not alter the magnitude of the odds ratios. Overall, in men aged 45 to 64 years, ECG ischemia was significantly more frequent (36% excess) in those with positive parental history. CONCLUSIONS: Subjects in whom one or both parents died prematurely from cardiac-related diseases have signs of ischemia more frequently on their electrocardiogram, and this is independent of other risk factors.

Prognostic value of ischemic electrocardiographic findings for cardiovascular mortality in men and women.

OBJECTIVES: The aim of this study was to investigate the independent prognostic value of ischemic electrocardiographic (ECG) findings for cardiovascular mortality and to evaluate a possible sex-differential in this regard. BACKGROUND: In previous reports, ST segment and T wave changes on the resting ECG were described as independent risk factors for development of coronary heart disease. Although more prevalent in women, they are often given less clinical importance than in men. METHODS: Ten-year follow-up data from the Belgian Interuniversity Research on Nutrition and Health study were used. The results presented here are based on ECGs of the 4,797 men and 4,320 women, aged 25 to 74 years, who were free of angina pectoris at the start of follow-up, had no history of myocardial infarction (MI) and showed no Q wave evidence of an old MI on their ECG. RESULTS: At baseline, the age-standardized prevalence of an "ischemic ECG" (Minnesota codes I3, IV1-3, V1-3 or VII1) was 8.4% in men and 10.6% in women. Cardiovascular mortality rates in men and women with an ischemic ECG were respectively 7.7 and 2.6 per 1,000 person-years, compared with 2.3 and 1.0 in those with no such ECG findings. After correction for the potential confounding effects of established cardiovascular disease (CVD) risk factors, the multivariately adjusted risk ratios were 2.45 (95% confidence interval [CI]: 1.70 to 3.53) for men and 2.16 (95% CI: 1.30 to 3.58) for women. Testing the interaction between an ischemic ECG and sex on CVD mortality revealed that the risk ratios were not significantly changed (p=0.95). The etiologic fraction of CVD deaths attributable to an ischemic ECG was estimated as 19.3% for men and 22.4% for women. Both men and women with major ischemic findings in their baseline electrocardiogram (Minnesota codes IV1,2, V1,2 or VII1) had a fourfold increased risk of CVD death. CONCLUSION: These results support the hypothesis that women with ischemic ECG findings are at the same increased risk for CVD mortality as men.

[Application of a dietary pattern approach in the Belgium context]. / Application de l'approche globale de l'alimentation dans la population belge.

BACKGROUND: Dietary pattern analysis has recently emerged as a new direction and a complementary approach to study the relationship between diet and morbidity or mortality. At present, two methods have been developed to construct dietary patterns: "a priori" method and "a posteriori" method. OBJECTIVE: This paper presents the two methods and their application based on dietary data from the "Belgium Interuniversity on Nutrition and Health Study". METHODS: A prospective study was conducted (1979-1984) in a sample of 5,225 males and 4,476 females from the Belgian population aged 25 to 74 years at the initial survey and followed for 10 years for all causes and specific mortality. Dietary data was collected by a 24-hour recall and for a sub-sample also by a 7 day-diet record. The "a priori" method was used by calculating an index based on the national dietary guidelines. We used the principal component analysis to identify dietary patterns a posteriori. We conducted a first principal component analysis using the data from the 24-hour recall and a second on the data collected by the 7 day-record. RESULTS: Both of the currently used approaches for extracting dietary patterns have advantages and limitations. We applied first the "a priori" approach by calculating an Index (IAR) which measures the adherence of the sample to the Belgian dietary guidelines. We obtained an index that ranged from 0 to 8, a higher score represented a "healthier diet". The index mean (sd) was 3.7 (+/- 1.2) for the entire sample with a significantly higher IAR for women. Using factor analysis, we identified 8 dietary patterns for men and for women. These were difficult to translate in terms of dietary intake profile. Inversely, with the factors identified with the 7 day record, we could find a "western" dietary profile and a "prudent" profile. CONCLUSION: Dietary pattern analysis offers the opportunity to evaluate the overall quality of the diet. The dietary profiles constructed by the two approaches should be related to morbidity or mortality in order to evaluate their predictive capacity.

Epidemiological aspects of high density lipoprotein cholesterol.

Most of the results from epidemiologic studies support the general idea that high density lipoproteins (HDL) cholesterol is inversely related to coronary heart disease (CHD) incidence. Results from the literature and from a large cohort study in Belgium (the BIRNH study) are used to describe the distribution and the major determinants of HDL cholesterol. HDL cholesterol is influenced by a variety of biologic, environmental and behavioral characteristics. Results of a 10-year mortality follow-up of the BIRNH study are presented and compared to those observed in other large cohort studies. The inverse relationship between HDL cholesterol and CHD is confirmed, although the strength of the association varies between studies and is weakened after adjustment for other coronary risk factors. The results from the BIRNH study also suggest that the relation between HDL cholesterol and CVD mortality is curvilinear. At present, only indirect evidence is available to support the idea that raising HDL cholesterol is useful in primary and secondary prevention of CHD.

Efficacy and tolerance of 200 mg micronised fenofibrate administered over a 6-month period in hyperlipidaemic patients: an open Belgian multicenter study.

The authors report the results of a large open multicenter study using 200 mg micronised fenofibrate once a day. Among 1545 selected patients who underwent a 3-month period with nutritional advice, 1334 were included in a 6-month drug study. Inclusion criteria were total serum cholesterol equal to or above 250 mg/dl and/or serum triglycerides equal to or above 200 mg/dl. At 6 months, average changes from inclusion levels were -20.5, -26.1. -7.5 and +15.2% for total cholesterol, LDL-cholesterol > or = 160 mg/dl on inclusion, plasma fibrinogen and HDL-cholesterol, respectively. Median decrease of serum triglycerides was 46.5%. Trial discontinuation for clinical and biological adverse events were 5 and 1%, respectively. In conclusion, micronised fenofibrate at a daily dose of 200 mg had significant lipid-modifying properties but also exhibited a beneficial effect on other related risk factors such as fibrinogen reduction. The safety profile was very satisfactory providing an excellent benefit/risk ratio.

Epidemiological evidence for an association between serum calcium and serum lipids.

To study the association between serum calcium and serum lipids, data from 5394 men and 4800 women in the Belgian Interuniversity Research on Nutrition and Health (25-74 years) were used. By visual inspection of the data a linear increase of both total and HDL cholesterol with serum calcium levels was observed, consistently over all age groups and both sexes. In order to adjust the measured serum calcium concentrations for total serum protein, statistical analyses were performed using Parfitt's correction formula. Multivariate analysis showed in both sexes a highly significant positive association between corrected calcium and total cholesterol independent of age, systolic blood pressure, body mass index, serum uric acid, P/S ratio of diet, cholesterol intake, smoking, educational level and geographical area. The adjusted differences in total cholesterol between the lowest and highest quartile range of the calcium distribution were about 13 mg/dl for both men and women. Protein-corrected calcium was among the strongest correlates with total cholesterol. The analysis of the relation with HDL cholesterol revealed an effect modification by gender. For men no statistically significant correlation between calcium and HDL cholesterol was observed while for women a strong increase of HDL with protein-corrected calcium was found resulting in an adjusted difference of 2.5 mg/dl between the lowest and highest calcium quartile range.

Haptoglobin polymorphism as a risk factor for coronary heart disease mortality.

OBJECTIVES: the aim of our study was to evaluate the independent role of the haptoglobin (Hp) polymorphism as a risk factor for coronary heart disease (CHD) mortality. METHODS: within the framework of the longitudinal part of the Belgian Interuniversity Research on Nutrition and Health (BIRNH) survey, a nested case-control study design was performed through matching the 107 deaths from CHD, occurring within a 10-year follow-up period, with three controls for age and gender. RESULTS: the distribution of the Hp types was found to be in Hardy-Weinberg equilibrium. Conditional logistic regression analysis for matched sets revealed that the Hp polymorphism was significantly associated with CHD death. Rather surprisingly, the finding was that Hp 1-1 individuals were at doubled risk for CHD mortality compared with the others, the odds ratio being 2.09 (95% CI: 1.22-3.60). The association was independent from other classical cardiovascular risk factors and the Hp concentration, and of comparable magnitude between men and women. Moreover, evaluating the interaction term in a multiplicative model showed that the Hp type did not play a synergistic role in the prognostic value of established cardiovascular risk factors. CONCLUSION: in contrast to the findings from cross-sectionally based studies, the results from this longitudinal study show that Hp 1-1 individuals are at elevated risk for CHD mortality.

Relationship between serum cholesteryl ester composition, dietary habits and coronary risk factors in middle-aged men.

Serum cholesteryl palmitate, oleate, linoleate and arachidonate were measured using high performance liquid chromatography in 134 men aged 45-64 years, randomly selected from the population of Ghent, Belgium. No relationship was observed between these cholesteryl esters, expressed as a percentage of their total, and age, serum cholesterol, arterial blood pressure, smoking habits and body mass index. Dietary habits were assessed using a 3-day diary method. No relationship was found between dietary habits and serum lipids. Highly significant correlations were observed between diet and the serum cholesteryl esters. In multivariate analyses dietary variables account for significant proportions of the variances of the serum cholesteryl esters. The results indicate that measurements of cholesteryl esters can be used to differentiate on the population level between subgroups with different dietary habits particularly with respect to fat consumption.

Quantitation of plasma free cholesterol and cholesteryl esters by high performance liquid chromatography. Study of a normal population.

We describe a convenient method for the separation and quantitation of plasma free cholesterol and cholesteryl esters by high performance liquid chromatography (HPLC). After extraction of 100 microliters plasma with isopropanol the plasma cholesteryl esters were resolved on a Zorbax ODS reversed-phase column by isocratic elution with acetonitrile/isopropanol (50:50, v/v). Baseline separation of the plasma cholesteryl esters including the internal standard was obtained within a 25-min run. The intra- and interassay CV was less than 4%. The results obtained by HPLC show good agreement with enzymatic and gas-liquid chromatographic methods. High performance liquid chromatography provides a simple method for the quantitation of individual cholesteryl esters avoiding tedious chromatographic and derivatisation steps inherent to GLC. Our HPLC method was applied to the monitoring of plasma cholesteryl esters in a normal population and can also be used for the study of cholesteryl esters from lipid extracts of biological samples.

Parameters of inflammation and infection in a community based case-control study of coronary heart disease.

BACKGROUND: increased levels of systemic inflammatory markers appear to be related to coronary heart disease (CHD) both in asymptomatic individuals and in subjects with established CHD. Whether these associations are related to confounding coronary risk factors or are explicable through chronic infectious conditions is not clear. OBJECTIVES: (1) to determine whether subjects with stable CHD differ from normal controls in inflammatory markers (CRP, SAA and fibrinogen) and/or in serostatus of four infectious agents (Helicobacter pylori, Chlamydia pneumoniae, CMV and EBV), independent of classical coronary risk factors. (2) To determine whether these inflammatory markers are related to the serostatus against these four infectious agents either in patients with CHD or in normal subjects. METHODS: in a large epidemiologic survey, 446 out of 16307 men at work, aged 35-59 years, had antecedents of myocardial infarction, CABG or PTCA or had prominent Q/QS waves on their resting ECG. They were compared with double the number (n=892) of men, matched for age, educational level and industry. Inflammatory biomarkers (CRP, fibrinogen and SAA) and antibodies against H. pylori, C. pneumoniae, CMV and EBV were measured, besides classical coronary risk factors. RESULTS: in univariate analyses, cases had higher CRP, fibrinogen and SAA levels than controls, but no differences were observed in serumantibody levels to any of the infectious agents. Markers of previous infections were not related to inflammatory biomarkers. In multivariate analyses CRP was significantly different between cases and controls independent of differences in other coronary risk factors and in the use of lipid lowering drugs and antiplatelet aggregants. CONCLUSIONS: in men at work with CHD, CRP levels are significantly different from controls, independent of known risk factors. No association was found between inflammatory biomarkers and positive serostatus against four infectious agents, neither in the patients nor in the healthy controls.

Trends in the prevalence, detection, treatment and control of arterial hypertension in the Belgian adult population.

OBJECTIVES: To discuss changes during the past decades in the prevalence and in the patterns of detection, treatment and control of arterial hypertension in the general Belgian population aged 25-64 years. DESIGN: Data from two cross-sectional cardiovascular disease risk factor surveys of the general population aged 25-64 years during the first and second halves of the 1980s (the Belgian Inter-university Research on Nutrition and Health study of 1980-1984 and the World Health Organization Multinational Monitoring of Trends and Determinants in Cardiovascular Diseases study of 1985-1992) are compared. PARTICIPANTS: Age-stratified and sex-stratified random samples from the general population yielded 9372 participants in the former study and 4904 participants in the latter. METHODS: In both studies, blood pressure measurements and other variables were collected in the same standardized way and by the same observers. RESULTS: For both sexes, overall age-standardized prevalences of hypertension (subjects with systolic blood pressure > or = 160 mmHg or diastolic blood pressure > or = 95 mmHg or currently being administered antihypertensive drug treatment) were found to be significantly (P< 0.001) higher in the former than they were in the latter study. A significant decline in population mean systolic blood pressure values was observed for both sexes on going from the former data to the latter (falls of 6.0 and 7.3 mmHg for men and women, respectively, P< 0.01). In log-linear models, adjusted for age, a highly significant (P< 0.0001) favourable shift in the population distribution over the various categories of detection, treatment and control of hypertension was observed. This trend exhibited a significant sex difference, however, there being a much more favourable trend for women. CONCLUSIONS: In Belgium, favourable trends in the prevalence and in the patterns of detection, treatment and control of arterial hypertension and in the levels of systolic blood pressure were observed. The so-called 'rule of halves' is no longer valid.

Design and methods of the Raloxifene Use for The Heart (RUTH) study.

Raloxifene is a selective estrogen receptor modulator that lowers total and low-density lipoprotein (LDL) cholesterol, reduces the risk of vertebral fracture, and is associated with a reduced incidence of invasive breast cancer in postmenopausal women with osteoporosis. The Raloxifene Use for The Heart (RUTH) trial is designed to determine whether raloxifene 60 mg/day compared with placebo: (1) lowers the risk of the coronary events (coronary death, nonfatal myocardial infarction [MI], or hospitalized acute coronary syndromes other than MI); and (2) reduces the risk of invasive breast cancer in women at risk for a major coronary event. RUTH is a double-blind, placebo-controlled, randomized clinical trial of 10,101 postmenopausal women aged > or =55 years from 26 countries. Women are eligible for randomization if they are postmenopausal and have documented coronary heart disease (CHD), peripheral arterial disease, or multiple risk factors for CHD. Use of estrogen within the previous 6 months is an exclusion factor. The study will be terminated after a minimum of 1,670 participants experience a primary coronary end point. Secondary end points include cardiovascular death, myocardial revascularization, noncoronary arterial revascularization, stroke, all-cause hospitalization, all-cause mortality, all breast cancers, clinical fractures, and venous thromboembolic events, in addition to the individual components of the composite primary coronary end point. RUTH will provide important information about the risk-benefit ratio of raloxifene in preventing acute coronary events and invasive breast cancer, as well as information about the natural history of CHD in women at risk of major coronary events.

Epidemiology of risk factors for hypertension: implications for prevention and therapy.

We review the present knowledge of risk factors for arterial hypertension. Both genetic and environmental factors as well as their interaction and biological plausibility are reviewed. Recent data confirm that the interaction of genetics with multiple environmental risk factors explains the high prevalence of hypertension in the industrialised countries. The most important modifiable environmental risk factors are high salt intake, alcohol intake, obesity and low physical activity. The role of stress in the aetiology of high blood pressure is still under investigation, but recent clinical experimental and epidemiological data have shed light on how stress could be related to hypertension. The implications for prevention and treatment are discussed both at the population and individual levels. The population approach involves a public health policy aiming at modification of the major risk factors. The individual approach involves nonpharmacological measures to prevent the development of hypertension and to treat high normal blood pressure and mild hypertension with no additional cardiovascular risk factors. Pharmacological treatment of hypertension in most individuals should use agents that have been proven to be effective in randomised controlled trials with 'hard' endpoints such as cardiovascular and cerebrovascular morbidity and mortality.

Regional differences in risk factor distributions, food habits and coronary heart disease mortality and morbidity in Belgium.

Belgium can be divided in 4 major geographical areas: two Dutch speaking areas in the north (Campine and Flanders), a French speaking area in the south (Wallonia) and the Brussels area in between. Significant differences in mean serum cholesterol levels were observed with the lowest level in Campine, intermediate in Flanders and Brussels, and the highest level in Wallonia. Similar differences were observed in the prevalence of CHD and mortality from CHD is also higher in the French speaking part of the country. A survey of food habits since 1959 shows a higher butter and lower soft margarine consumption in the south. However, differences in smoking habits and personality traits also exist.

PIP: The authors examine mortality differentials among the four major geographical areas of Belgium. Reasons for the higher coronary heart disease mortality in the French-speaking region are considered

Prognostic value of ECG findings for total, cardiovascular disease, and coronary heart disease death in men and women.

OBJECTIVE: To study abnormalities in the resting ECG as independent predictors for all cause, cardiovascular disease (CVD), and coronary heart disease (CHD) mortality in a population based random sample of men and women, and to explore whether their prognostic value is different between sexes. DESIGN AND SUBJECTS: An age and sex stratified random sample was selected from the total Belgian population aged 25 to 74 years. Baseline data were gathered and resting ECGs were classified according to Minnesota code criteria. The sample was then followed for at least 10 years with respect to cause specific death. Results are based on observations from 5208 men and 4746 women free from prevalent CHD at the start of the follow up period. RESULTS: Although the prevalence of major abnormalities in general was comparable between sexes, women had more ischaemic findings, ST segment changes, and abnormal T waves on their baseline ECG, while men showed more arrhythmias, bundle branch blocks, and left ventricular hypertrophy. Fitting the multiplicative effect on subsequent mortality between all ECG classifications under study and sex indicated that the prognostic value of ECG changes was equal in women and men. Independently of other risk factors and other major ECG changes, almost all ECG classifications were significantly related to all cause, CVD, and CHD mortality. The most predictive ECG findings for CVD death were ST segment depression (risk ratio (RR) 4.71), major ECG findings (RR 3.26), left ventricular hypertrophy (RR 2.79), bundle branch blocks (RR 2.58), T wave flattening (RR 2.47), ischaemic ECG findings (RR 2.35), and arrhythmias (RR 2.15). The prognostic value of major ECG findings for CVD and CHD death was more powerful than well established cardiovascular risk factors. CONCLUSIONS: Abnormalities in the baseline ECG are strongly associated with subsequent all cause, CVD, and CHD mortality. Their predictive value was similar for men and women.

Belgian heart disease prevention project: comparison of self-reported smoking behaviour with serum thiocyanate concentrations.

At the end of a multifactorial cardiovascular preventive trial serum thiocyanate was measured in random samples of 1035 cases and 1087 controls. A cut-off point 0.45 mg/dl (77.6/mumol/l) gave a sensitivity of 82.1% among the cigarette smokers in the control group and a specificity of 91.0% among the non-smokers. When the intervention and control groups are compared in terms of self-reported smoking behaviour non-significant differences in mean thiocyanate concentration are observed for those who never smoked, ex-cigarette smokers, actual cigarette smokers, and in four different cigarette smoking categories. Our results fail to confirm the reported pessimistic views concerning the validity of self-reported smoking behaviour in subjects taking part in intervention trials.

Misclassification of coronary heart disease in mortality statistics. Evidence from the WHO-MONICA Ghent-Charleroi Study in Belgium.

STUDY OBJECTIVE: To validate the Belgian vital statistics for coronary heart disease (CHD) on the basis of an independent acute myocardial infarction (AMI) register, carried out as part of the WHO-MONICA project. DESIGN: Records of fatal cases of AMI in the WHO-MONICA register were individually linked to the corresponding death certificates. SETTING: Since 1983, the WHO-MONICA Collaborating Centre Ghent/Charleroi registers all fatal and non-fatal AMI in the age group 25-69 years in two geographical areas, Ghent in the northern Dutch speaking part and Charleroi in the southern French speaking part of Belgium. Registration is done according to the MONICA protocol. The official vital statistics in Belgium are published on a yearly basis. They are essentially a reflection of the "underlying" causes of death, coded according to the 9th revision of the International Classification of Diseases (ICD). The study was undertaken in the period 1983-1991. MAIN RESULTS: Out of a total of 741 (Ghent) and 934 (Charleroi) well documented MONICA fatal cases of AMI, 492 (66.4%) and 641 (68.6%), respectively, were officially labelled as CHD (ICD code 410-414); 438 (59.1%) and 385 (41.2%), respectively, were officially labelled as AMI (ICD code 410). A substantial fraction of the MONICA AMI cases--27.1% in Ghent and 38.2% in Charleroi--was coded as "other forms of CHD" (ICD 411-414) or as "other forms of heart disease" (ICD 420-429). The remaining MONICA AMI cases--13.8% in Ghent and 20.6% in Charleroi--were classified in either very aspecific (for example, atherosclerosis, ICD 440) or totally unrelated ICD codes (for example, neoplasm, ICD 140-239). CONCLUSIONS: It is concluded from the results in this paper that a substantial part of all deaths caused by CHD in Belgium are labelled with incorrect ICD codes and are therefore misclassified in the official mortality statistics for Belgium. This is partly caused by a "drainage" of cases towards less specific CHD related ICD categories. A considerable fraction, however, seems to be absolutely misclassified.

Occupational stress and incidence of sick leave in the Belgian workforce: the Belstress study.

CONTEXT: Sick leave is a major problem in public health. The Karasek demands/control/social support/strain (JDCS) model has been largely used to predict a wide range of health outcomes and to a lesser extent sickness absence. STUDY OBJECTIVE: The aim of the study was to test the predictive power of the JDCS model in relation with one year incidence of sick leave in a large cohort of workers. DESIGN AND SETTING: Cohort study conducted between 1994 and 1998 in 25 companies across Belgium. PARTICIPANTS: A total of 20 463 workers aged 35 to 59 years were followed up for sick leave during one year after the baseline survey. OUTCOMES: The outcomes were a high sick leave incidence, short spells (>/=7 days), long spells (>/=28 days), and repetitive spells of sickness absence (>/=3 spells/year). MAIN RESULTS: Independently from baseline confounding variables, a significant association between high strained jobs with low social support and repetitive spells of sickness absence was observed in both sexes with odds ratios of 1.32 (99% CI, 1.04 to 1.68) in men and 1.61 (99% CI, 1.13 to 2.33) in women. In men, high strained jobs with low social support was also significantly associated with high sick leave incidence, and short spells of sick leave with odds ratios of 1.38 (99% CI, 1.16 to 1.64) and 1.22 (99% CI, 1.05 to 1.44) respectively. CONCLUSIONS: Perceived high strain at work especially combined with low social support is predictive of sick leave in both sexes of a large cohort of the Belgian workforce.

Trends in coronary heart disease in two Belgian areas: results from the MONICA Ghent-Charleroi Study.

SETTING: As part of the WHO-MONICA study, acute coronary events have been registered from 1983 until 1992 in the general population aged 25-69 years in two Belgian cities--Ghent in the northern Dutch speaking part of Belgium and Charleroi in the southern French speaking part. Registration of events was done according to an international standard protocol. OBJECTIVE: To study trends in total, fatal and non-fatal event rates and trends in case fatality rates in these two cities. MAIN RESULTS: Incidence of CHD was on average 50% higher in Charleroi compared with Ghent in both men and women (attack rate ratio Charleroi/Ghent was 1.5 in both sexes). In both men and women, diverging trends were observed between the two cities for total and non-fatal event rates, while parallel declining trends were observed in fatal event rates and in case fatality rates. In both sexes, total attack rates showed a significant decrease in Ghent and a significant increase in Charleroi. Also in the two sexes, attack rates of non-fatal events increased significantly in Charleroi and remained stable in Ghent. Attack rates of fatal events decreased significantly in men and women in Ghent and in men in Charleroi. Both "total" and "in hospital" case fatality rates declined significantly in both sexes in the two cities. CONCLUSIONS: Important differences in coronary heart disease (CHD) incidence and CHD trends between Ghent and Charleroi were observed. These differences and trends are interpreted in the context of existing and still growing differences in the overall socioeconomic situation between the north and the south of the country. On the other hand, the efficacy of medical treatment of CHD is comparable in the two regions, as reflected by similar figures and trends for case fatality rates.