Do Vascular Risk Factors Explain the Association between Socioeconomic Status and Stroke Incidence: A Meta-Analysis

Background: Reduced socioeconomic status (SES) is associated with an increased risk of stroke, although the mechanism is not clear. It may be that those with lower SES have a greater burden of classic vascular risk factors. Methods: Our aim was to quantify the extent to which classic vascular risk factors explain the association between SES and stroke incidence. We conducted a systematic review and meta-analysis of studies examining the association of SES and stroke incidence, where classic vascular risk factors were considered. Searching MEDLINE, EMBASE and the Cochrane Library from 1980 onwards we identified 17 studies, 12 of these studies provided sufficient information to allow a meta-analysis. From each study the increased risk of stroke incidence, where the lowest socioeconomic category was compared with the highest, was recorded and pooled. The stroke incidence risks, adjusted for grouped classic risk factors, were also pooled. Review Manager 5 software was used for all analyses and results were analysed using hazard ratios (HR, 95% confidence interval, 95% CI) with a random effects model. Results: Those with a lower SES were more likely to have a stroke (HR 1.67; 95% CI 1.46-1.91). Additional risk was reduced, but not eliminated, when classic vascular risk factors were adjusted for (HR 1.31; 95% CI 1.16-1.48). Conclusion: Low SES is associated with an increased risk of stroke that is partly explained by known classic vascular risk factors. Copyright (C) 2010 S. Karger AG, Basel