Combined work and leisure physical activity and risk of stroke in men and women in the European prospective investigation into Cancer-Norfolk Prospective Population Study

Most studies to date support a protective role of physical activity in reducing stroke risk. However, they were not able to take into account combined work and leisure activity. We prospectively followed up 22,602 men and women aged 40-79 years, who had no history of stroke and myocardial infarction at baseline, participating in the European Prospective Investigation into Cancer-Norfolk. Participants were categorized into four levels of physical activity based on a validated self-reported questionnaire, which assesses combined work and leisure activities, at baseline during the period from 1993 to 1997. Stroke incidence was ascertained by death certificate and hospital record linkage data up to 2004, average 8.6 years of follow-up. We used the Cox proportional hazards model. There were 361 incident strokes during follow-up (total person years = 195,092). After adjusting for age, sex, systolic blood pressure, body mass index, cholesterol, history of diabetes and smoking, men and women who were physically active were less likely to have a stroke (relative risk = 0.70, 95% CI: 0.49-0.99, p = 0.024) compared to those who were inactive. This highlights the fact that efforts to increase physical activity in both the work place and in leisure time should be encouraged.