The Relationship between Vitamin D Deficiency and Diabetic Retinopathy: A Cross-sectional Study Download PDF

Introduction: Diabetic Retinopathy (DR) is the most common cause of legal blindness among the working-age group. To date, its relationship with vitamin D deficiency remains ambiguous in the literature. This study aimed to fill this gap by further assessing the association between vitamin D deficiency and DR. 
Materials and Methods: A cross-sectional study was conducted at a diabetes center in Tabuk City, Saudi Arabia, from April 2019 to March 2020. A structured questionnaire was used to collect data regarding patient demography, the duration of diabetes, and any chronic diseases. It also included a series of direct interview questions for the participants regarding vitamin D supplementation and its related factors. Data related to DR were also reported. Furthermore, a blood sample was taken to measure the vitamin D levels of the participants. 
Results and Discussion: Out of the 174 participants with the diagnosis of diabetes mellitus (49.4% women) within the age range of 25–94 years (mean age 49.80±13.45) who participated in this study, retinopathy was found in 31%, and vitamin-D deficiency was reported in 36.8% of the participants. No relationship was established between DR and vitamin D deficiency (P-value 0.084), nor between retinopathy, Body Mass Index (BMI), and gender (P-values 0.117 and 0.637 respectively). However, DR was found to be associated with the duration of diabetes (P-value 0.004).
Conclusion: There was no evidence of a relationship between DR and vitamin D deficiency, and retinopathy was found to be not associated with BMI or gender. However, DR was found to be associated with the duration of the disorder