Change in stroke incidence from a population-based intervention trial in three urban communities in China

Stroke has been the main cause of death in most urban residents in China since the 1990s. A community-based intervention trial carried out in China aimed to reduce the incidence and mortality of stroke. In 1991, two well-matched communities each with approximately 50,000 people were selected as intervention or control communities in the urban areas of Beijing, Shanghai and Changsha. Regular health education and health promotion activities were carried out between 1991 and 2000 in the intervention communities but no special action was taken in the control communities. Both fatal and nonfatal stroke cases were meticulously registered during the study in the two communities to assess the effect of long-term intervention. The trend in stroke incidence and the effect of intervention on stroke incidence were analyzed using a Poisson regression model adjusted for age, sex, year and city. Between 1991 and 2000, 2,273 first-ever stroke cases were registered in the intervention communities and 3,015 in the control communities. Geographic variation and changes in the incidence of stroke and its subtypes were found among these 3 cities. Through 10 years of intervention, incidence risks of all, ischemic and hemorrhagic strokes decreased by 11.4% (relative risk 0.8959; 95% confidence interval, CI, 0.8483-0.9460; p < 0.0001), 13.2% (relative risk 0.8676; 95% CI 0.8054-0.9345; p = 0.0002) and 7.2% (relative risk 0.9283; 95% CI 0.8517-1.0117; p = 0.0899), respectively, in the intervention compared with control communities. Accordingly, comprehensive community-based intervention measures could effectively reduce the incidence of stroke in the population.