Socioeconomic deprivation and development of diabetic retinopathy in patients with type 1 diabetes mellitus

INTRODUCTION: Very little is known about the influence of socioeconomic status on type 1 diabetes mellitus (T1DM) complications. Our aim was to determine whether socioeconomic level is a risk factor for the development of diabetic retinopathy (DR) in patients with T1DM. RESEARCH DESIGN AND METHODS: A cohort of 150 patients with T1DM were studied prospectively over 9 years. Socioeconomic status was assessed using a neighborhood-level measure based on an index of deprivation. The contribution of other variables such as hypertension, dyslipidemia, diabetic nephropathy and smoking habit was evaluated. Cox proportional hazards models were used to quantify the associations. RESULTS: The incidence of DR was 21.6 cases per 1000 patient-years. Multivariable analyses showed that for each percentage point increase in glycated hemoglobin (HbA1c), the risk of developing DR increased by 58% (HR 1.58, 95% CI 1.19 to 2.10). Patients with T1DM onset >18 years of age and resident in areas of lower socioeconomic levels presented with almost triple the risk of developing DR (HR 2.95, 95% CI 1.08 to 8.00) compared with those with onset <18 years of age and resident in less deprived areas. We did not find significant relationships with other variables studied such as hypertension, dyslipidemia, diabetic nephropathy and smoking habit. CONCLUSIONS: Low socioeconomic level is a risk factor, independent of glycemic control, in the development of DR in patients with T1DM when the onset of diabetes is in adulthood. This finding indicates that socioeconomic status and age of onset need to be considered in population screening for DR in patients with T1DM.