Socioeconomic disparities in stroke rates and outcome: Pooled analysis of stroke incidence studies in Australia and New Zealand

Objective: To assessthe influence of area-level socioeconomic status (SES) on incidence andcase-fatality rates for stroke.

Design,setting and participants: Analysis of pooled data for3077 patients with incident stroke from three population-based studies inPerth, Melbourne, and Auckland between 1995 and 2003.

Mainoutcome measures: Incidence and 12-month case-fatality rates forstroke.

Results: Annualage-standardised stroke incidence rates ranged from 77 per100 000 person-years (95% CI, 72–83) in the least deprived areas to131 per 100 000 person-years (95% CI, 120–141) in the mostdeprived areas (rate ratio, 1.70; 95% CI, 1.47–1.95; P < 0.001).The population attributable risk of stroke was 19% (95% CI, 12%–27%) for thoseliving in the most deprived areas compared with the least deprived areas.Compared with people in the least deprived areas, those in the most deprivedareas tended to be younger (mean age, 68 v 77 years; P < 0.001),had more comorbidities such as hypertension (58% v 51%; P < 0.001)and diabetes (22% v 12%; P < 0.001), and were more likely tosmoke (23% v 8%; P < 0.001). After adjustment for age,area-level SES was not associated with 12-month case-fatality rate.

Conclusions: Our analysis provides evidence that people living inareas that are relatively more deprived in socioeconomic terms experiencehigher rates of stroke. This may be explained by a higher prevalence of riskfactors among these populations, such as hypertension, diabetes and cigarettesmoking. Effective preventive measures in the more deprived areas of the communitycould substantially reduce rates of stroke.