Background and purpose: To estimate the predictive value of risk factors for stroke measured in midlife over follow-up extending through 28 years.
Methods: A cohort of 7457 men 47 to 55 years of age and free of stroke at baseline year 1970 were examined. Risk of stroke was analyzed for the entire period and for 0 to 15, 16 to 21, and 22 to 28 years of follow-up using age-adjusted and multiple Cox regression analyses.
Results: Age, diabetes, and high blood pressure were independently associated with increased risk of stroke for the entire 28 years and for each of the periods. Previous transient ischemic attacks, atrial fibrillation, history of chest pain, smoking, and psychological stress were independently related to stroke for the entire follow-up period and also during the first 1 or 2 successive periods. Family history of stroke or of coronary disease carried no independent prognostic information, nor did serum cholesterol. Elevated body mass index predicted stroke during the later part of the follow-up and so did (almost) low physical activity during leisure time, together with antihypertensive medication at baseline.
Conclusions: High blood pressure and diabetes retain their importance as stroke risk factors also over an extended follow-up into old age. A family history of cardiovascular disease was not significantly related to outcome. Transient ischemic attacks, atrial fibrillation, stress, smoking, and a history of chest pain were associated with outcome only for the first or the first 2 periods. High body mass index and antihypertensive medication at baseline emerged as risk factors in the second and third decades.