Abstract 139: Relative Improvements in Country-level Measures of Stroke Mortality, Incidence, and Disability From 1990 to 2010 are Associated With Higher Baseline Gross National Income Per Capita

Abstract

Background: Age-standardized mortality and disability burden from stroke has been improving on a global level, but these improvements have been uneven across nations. Hypothesis: Higher gross national income per capita is strongly associated with relative improvements in stroke indicators on a national level. Methods: We conducted an ecological analysis using estimates of age-standardized stroke indicators (Global Burden of Disease Study 1990 and 2010), non-communicable disease risk factor data (WHO Global Health Observatory), and gross national income per capita estimates (World Bank). We generated choropleth maps to highlight outliers with changes that differed from global trends. We evaluated the association between gross national income per capita and changes in risk factors burden and age-standardized mortality, incidence, mortality incidence ratio, and DALY losses from stroke over 20 years. Results: Of the 186 countries with available data, most experienced a decrease in age-standardized stroke mortality (164; 88%; mean decrease 23%), mortality incidence ratio (175; 94%; mean decrease 25%), and stroke DALY losses (168; 90%; mean decrease 27%) but not stroke incidence (76; 40%; mean increase 10%) over 20 years (Figure). Relative improvements in mean systolic blood pressure (p<0.0001), mean serum cholesterol (p<0.0001) and smoking prevalence (p=0.006) were associated with higher gross national income, but not mean fasting serum glucose (p=0.43). Relative improvements in age-standardized mortality, incidence, mortality incidence ratio, and DALY losses for stroke tracked with higher income per capita (Cuzick’s test of trend, p<0.001 for each indicator). Conclusion: Incidence, mortality, and DALY burdens from stroke are higher in low-income countries, but the greatest relative improvements in these indicators over the past 20 years have been in high-income countries.