Clustering of cardiovascular risk factors. time trends during 28 years

To assess the development in frequency and clustering of hypertension, hypercholesterolaemia, high body mass index (BMI), physical inactivity and tobacco smoking in the period 1964-1992, and to evaluate any sex and age differences.

Five cross-sectional investigations on cardiovascular risk factors performed in 1964, 1978, 1982-1984, 1986-1987 and 1991-1992 comprising random samples in a suburban area of Copenhagen, Denmark. Physical activity during leisure time and smoking habits were assessed by self-administered questionnaire. Blood pressure, weight, height and serum total cholesterol were measured according to WHO standards.

A total of 8644 persons aged 30, 40, 50 and 60 years participated with an equal number of men and women. Women had fewer risk factors than men and younger persons had fewer risk factors than older persons. In the period 1964-1992 there was a decreasing number of risk factors. The 50 year olds show a sex difference in the period 1982-1992, whereas there was no sex difference among the 60 year olds. Tobacco smoking was the most common risk factor. BMI > 27.5 has become more and more frequent throughout the period, especially in men. The BMI has conquered third place in all age groups. The association of BMI > 27.5 and sedentary leisure time physical activity has become the most frequent.

Clustering among risk factors decreased over time in both sexes. The association of elevated BMI and sedentary leisure time activity may contribute to the rising frequency of chronic disease such as diabetes mellitus and cardiovascular disease.