Total and HDL-Cholesterol in The Netherlands: 1987–1992. Levels and Changes over Time in Relation to Age, Gender and Educational Level

BACKGROUND: To gain insight into the prevalence of and trends in plasma cholesterol levels in the general population of the Netherlands, a monitoring project was carried out from 1987 to 1992. METHODS: Each year a random sample of men and women aged 20-59 years in three towns in the Netherlands was invited to participate in the study. The overall response rate was 50% for men and 57% for women and a total of almost 42,000 men and women participated. Total (TC) and high density lipoprotein cholesterol (HDL-C) was measured and the non-HDL-C/HDL-C ratio was computed. Data were age-standardized to the Dutch population distribution aged 20-59 years. RESULTS: The prevalence of hypercholesterolaemia (TC > or = 6.5 mmol/l) in men ranged from 5% in the youngest (20-29 years) to 29% in the oldest age group (50-59 years), and from 4% to 38% in women. Low HDL-C levels (< or = 0.9 mmol/l) in men ranged from 15% in the youngest to 26% in the oldest age group, and in women from 4% in the youngest to 7% in the oldest age group. The lipid profile of those with a higher educational level was more favourable than that of the less educated. From 1987 to 1992, in men, TC decreased by 0.12 mmol/l, HDL-C decreased by 0.07 mmol/l and the non-HDL-C/HDL-C ratio increased by 0.22. In women no statistically significant changes were observed. Changes over time did not differ according to age and educational level. CONCLUSION: The prevalence of hypercholesterolaemia is still high in the Netherlands. During the period 1987-1992 the lipid profile worsened in men and remained stable in women.