Acute myocardial infarction in patients treated for hypertension in the Skaraborg Hypertension Project.

The Skaraborg Hypertension Project was undertaken in 1977-1981, and 1428 male and 1812 female hypertensives aged 40-69 years were involved at hypertension out-patient clinics in primary health care. Their long-term risk of acute myocardial infarction during a follow-up of 8.3 years was compared to that of age- and sex-matched controls drawn from the census register at the beginning of surveillance and to normotensive untreated controls identified in a population survey in 1977. Relative risks (with a 95% confidence interval) for acute myocardial infarction morbidity compared to the population was 0.99 (0.78, 1.25) in men and 1.36 (0.95, 1.94) in women. Corresponding figures for acute myocardial infarction mortality were 0.97 (0.68, 1.38) and 1.15 (0.67, 1.99). With normotensive controls used as reference and adjusting for smoking habits and body mass index, the relative risks for acute myocardial infarction morbidity were 1.48 (1.12, 1.98) in men and 2.34 (1.43, 3.85) in women, and for acute myocardial infarction mortality 1.66 (1.07, 2.57) and 1.71 (0.84, 3.48), respectively. Treated hypertension is a weak risk factor for acute myocardial infarction in unselected hypertensive patients.