Serum cholesterol and long-term prognosis in middle-aged men with myocardial infarction and angina pectoris: A 16-year follow-up of the Primary Prevention Study in Gateborg, Sweden

Abstract

To compare the role of serum cholesterol in the long-term prognosis of men with a history of myocardial infarction, in men with clinical angina without myocardial infarction, and men without clinical coronary disease. In the second screening of the Primary Prevention Study in Göteborg which comprised 7100 men aged 51 to 59 years at baseline in 1974–1977, 314 men with clinical angina but no myocardial infarction at baseline were identified and 195 men who had survived a myocardial infarction for 0 to 19 years (median 3 years). Of the men without clinical coronary disease at baseline and cholesterol at or below 5·2 mmol .1⁻¹, 2·7 per 1000 observation years died from coronary disease compared to 8·5 per 1000 of the men with serum cholesterol of 7·2 mmol .1⁻¹ or more. Corresponding figures for men with angina was 5·5 and 31·0 per 1000 observation years, and for men with prior myocardial infarction 19·8 and 58·3 respectively, per 1000. After adjustment for age, smoking, systolic blood pressure, body mass index and diabetes the risk of coronary death in men with serum cholesterol above 7·2 mmol .1⁻¹ compared to below 5·2 mmol .1⁻¹ was 2·42 (1·66–3·51) in healthy men, 4·82 (1·44–16·09) in men with angina, 2·70 (0·95–7·67) in survivors of myocardial infarction, and 4·07 (1·86–8·91) in the combined group of men with either angina or prior infarction. The strongest effect was seen during the first half of the follow-up, with an adjusted relative risk for high in relation to low serum cholesterol of 8·08 (1·95–33·55) in men with preexisting coronary disease. Non-coronary deaths varied little by serum cholesterol or coronary disease status at baseline. After 16 years, 76% of the healthy men with low cholesterol and 65% of healthy men with cholesterol above 7·2 mmol. 1⁻¹ were still alive. Of the men with prior myocardial infarction, 50% in the group with low cholesterol were alive after 16 years, as compared to 21% of those with high cholesterol. The long-term absolute risk of death in men with coronary disease and elevated serum cholesterol is very high. Implementation of lipid-lowering strategies shown to be efficacious is important in this high-risk group.