title: Population aging, macroeconomic changes, and global diabetes prevalence, 1990-2008.
abstract: BACKGROUND
  Diabetes is an important contributor to global morbidity and mortality. The contributions of population aging and macroeconomic changes to the growth in diabetes prevalence over the past 20 years are unclear.
  
  
  METHODS
  We used cross-sectional data on age- and sex-specific counts of people with diabetes by country, national population estimates, and country-specific macroeconomic variables for the years 1990, 2000, and 2008. Decomposition analysis was performed to quantify the contribution of population aging to the change in global diabetes prevalence between 1990 and 2008. Next, age-standardization was used to estimate the contribution of age composition to differences in diabetes prevalence between high-income (HIC) and low-to-middle-income countries (LMICs). Finally, we used non-parametric correlation and multivariate first-difference regression estimates to examine the relationship between macroeconomic changes and the change in diabetes prevalence between 1990 and 2008.
  
  
  RESULTS
  Globally, diabetes prevalence grew by two percentage points between 1990 (7.4 %) and 2008 (9.4 %). Population aging was responsible for 19 % of the growth, with 81 % attributable to increases in the age-specific prevalences. In both LMICs and HICs, about half the growth in age-specific prevalences was from increasing levels of diabetes between ages 45-65 (51 % in HICs and 46 % in LMICs). After age-standardization, the difference in the prevalence of diabetes between LMICs and HICs was larger (1.9 % point difference in 1990; 1.5 % point difference in 2008). We found no evidence that macroeconomic changes were associated with the growth in diabetes prevalence.
  
  
  CONCLUSIONS
  Population aging explains a minority of the recent growth in global diabetes prevalence. The increase in global diabetes between 1990 and 2008 was primarily due to an increase in the prevalence of diabetes at ages 45-65. We do not find evidence that basic indicators of economic growth, development, globalization, or urbanization were related to rising levels of diabetes between 1990 and 2008.
authors.affiliation: Population Studies Center, University of Pennsylvania, 239 McNeil Building, 3718 Locust Walk, Philadelphia, PA 19104 USA.
authors.forename: Nikkil
authors.initials: N
authors.lastname: Sudharsanan
authors.affiliation: Hubert Department of Global Health, Emory University, 1518 Clifton Road NE, Atlanta, GA 30322 USA.
authors.forename: Mohammed K
authors.initials: MK
authors.lastname: Ali
authors.affiliation: Hubert Department of Global Health, Emory University, 1518 Clifton Road NE, Atlanta, GA 30322 USA.
authors.forename: Neil K
authors.initials: NK
authors.lastname: Mehta
authors.affiliation: Hubert Department of Global Health, Emory University, 1518 Clifton Road NE, Atlanta, GA 30322 USA.
authors.forename: K M Venkat
authors.initials: KM
authors.lastname: Narayan
keywords: Diabetes; Economic growth; Globalization; Population aging; Urbanization