Aims/hypothesis: The aim of this study was to assess the role of socioeconomic status (SES) in the associations between type 2 diabetes and life expectancy in a complete national population.
Methods: An observational population-based cohort study was performed using the Scottish Care Information - Diabetes database. Age-specific life expectancy (stratified by SES) was calculated for all individuals with type 2 diabetes in the age range 40-89 during the period 2012-2014, and for the remaining population of Scotland aged 40-89 without type 2 diabetes. Differences in life expectancy between the two groups were calculated.
Results: Results were based on 272,597 individuals with type 2 diabetes and 2.75 million people without type 2 diabetes (total for 2013, the middle calendar year of the study period). With the exception of deprived men aged 80-89, life expectancy in people with type 2 diabetes was significantly reduced (relative to the type 2 diabetes-free population) at all ages and levels of SES. Differences in life expectancy ranged from -5.5 years (95% CI -6.2, -4.8) for women aged 40-44 in the second most-deprived quintile of SES, to 0.1 years (95% CI -0.2, 0.4) for men aged 85-89 in the most-deprived quintile of SES. Observed life-expectancy deficits in those with type 2 diabetes were generally greater in women than in men.
Conclusions/interpretation: Type 2 diabetes is associated with reduced life expectancy at almost all ages and levels of SES. Elimination of life-expectancy deficits in individuals with type 2 diabetes will require prevention and management strategies targeted at all social strata (not just deprived groups).
Keywords: Epidemiology; Life expectancy; Socioeconomic status; Type 2 diabetes.