Is vitamin D deficiency associated with retinopathy in type 2 diabetes mellitus? A case-control study.

Background And Aims: This study aimed to determine the associations between vitamin D deficiency and diabetic retinopathy (DR) progression risk in type 2 diabetes mellitus (T2DM) patients.

Methods: This is a case-control study that enrolled 201 diabetic retinopathy (DR) patients as case and 201 T2DM without DR as a control. Demographic variables were obtained during an interview using a questionnaire, furthermore, anthropometric measures were evaluated based on the standard protocol.