Determinants of Socioeconomic Inequalities in the Use of Eye Care Services among Individuals with Diabetes in Alberta, Canada 1995-2009

Determinants of Socioeconomic Inequalities in the Use of Eye Care Services among Individuals with Diabetes in Alberta, Canada 1995-2009

Diabetic retinopathy (DR) is a serious life-threatening complication in individuals with diabetes. The Canadian Diabetes Association clinical guidelines recommend an annual dilated eye examination by an eye care specialist for timely detection and effective prevention. Previous studies have suggested that socioeconomic status (SES) is associated with use of the recommended eye care services. However, Canadian evidence on the factors associated with SES-related inequalities in the use of eye screening services among individuals with diabetes is limited. Therefore, the aim of this aim of this study was to assess SES-related inequalities, in the of eye care services among individuals with diabetes in Alberta, Canada. We applied the econometric techniques of Concentration Index (CI), and used regression-based decomposition analysis to identify major contributors to SES-related inequalities. Horizontal inequity index (HI), which represents equal access for equal need, was calculated based on decomposition methods by quantifying contributions of need and non-need factors. SES was represented by 3 different measures: census-based median household income, and material (MDI) and social deprivation (SDI) indices. This study used data from the Alberta Diabetes Surveillance System (ADSS) 1995-2009: a total of 1,949,498 individuals with diabetes over a 15-year period were included in the analyses. Eye care service was defined in this study as any visit to an ophthalmologist, based on the medical services claims database. The study found horizontal inequity among individuals with diabetes in the use of eye care services by an ophthalmologist but these differed depending on the specific SES indicator. Income and material deprivation-related His have been in favor of richer groups (i.e., pro-rich), however, the social deprivation-related His have been in favor of poorer groups (i.e. socially deprived individuals with diabetes tended to use more eye screening services than those who were less socially deprived). In addition, the study found that the MDI and place of residence (urban/rural) were important contributors to the observed “pro-rich” income-and MDI-related CIs. The observed SDI-related inequity was explained by SDI itself. The findings imply that economic- and social-related resources generate different directions of inequalities in the use of eye screening services and also suggest the need for developing health policy to alleviate different determinants if SES-related inequalities in the use of eye screening services in individuals with diabetes in Alberta.