RISK-FACTORS FOR STROKE IN COPENHAGEN, DENMARK .2. LIFE-STYLE FACTORS

The objective of the present work was to identify independent life-sty le factors for stroke and to estimate their causal contribution. The s tudy is based on a random sample of the Copenhagen population selected in 1976 and stratified by age. The present analysis includes 12,961 s ubjects examined initially, aged 35 or over and without a previous cer ebrovascular event, for whom information about life-style factors was recorded between 1976 and 1978. The outcome was the first-in-life stro ke or transient ischemic attack during 12 years of follow-up. The even ts were ascertained at a second examination 5 years later and from hos pital records and death certificates through 1988. Cox's regression mo del was used to estimate the effect on stroke risk of the factors reco rded. In the period 1976-1988, 693 initial events were recorded in eli gible responders. Among the lifte-style factors analyzed, a significan t, independent effect was found for cigarette smoking, daily consumpti on of sleeping pills or tranquilizers and body mass index (BMI). There was a tendency for daily alcohol intake to be associated with lower r isk, this could not be demonstrated for physical activity at leisure t ime. Among smokers, stroke risk was influenced by the number of cigare ttes smoked, and daily alcohol intake was associated with a significan tly lower risk. The effect of smoking decreased with age. BMI in smoke rs still had a significant effect on stroke risk but neither daily con sumption of tranquilizers, nor physical inactivity at leisure time had a significant influence.