Physical activity and stroke mortality in women - Ten-year follow-up of the Nord-Trondelag Health Survey, 1984-1986

Background and Purpose-Few studies have reported a protective effect of phy sical activity on stroke in women, particularly among elderly women. This s tudy was conducted to examine the association between different levels of l eisure-time physical activity and stroke mortality in a large prospective s tudy of middle-aged and elderly women. Methods-We conducted a 10-year mortality follow-up of women aged greater th an or equal to 50 years, free from stroke at baseline (n=14101), who partic ipated in the Nord-Trondelag Health-Survey in Norway during 1984-1986. Main outcome measures were relative risk of stroke mortality according to incre asing levels of physical activity, with the least active group used as refe rence. Results-In groups aged 50 to 69, 70 to 79, and 80 to 101 years, the relativ e risk: of dying decreased with increasing physical activity, after adjustm ent for potentially confounding factors. In groups aged 50 to 69 and 70 to 79 years, the most active women had an adjusted relative risk of 0.42 (95% CI; 0.24 to 0.75) and 0.56(95% CI, 0.36 to 0.88), respectively. In the grou p aged 80 to 101 years, there was a consistent negative association with ph ysical activity; the adjusted relative risk for the most active was 0.57 (9 5% CI, 0.30 to 1.09). Conclusions-Physical activity was associated with reduced risk of death fro m stroke in middle-aged and elderly women. This association persisted after we excluded individuals with prevalent cardiovascular and cerebrovascular disease at baseline and women who died during the first 2 years of follow-u p. These observations strengthen the evidence that physical activity should be part of a primary prevention strategy against stroke in women.