Associação entre concentração de vitamina D e retinopatia em indivíduos com diabetes mellitus tipo 1

Abstract

ASSOCIATION BETWEEN VITAMIN D CONCENTRATION AND RETINOPHATY IN INDIVIDUALS WITH TYPE 1 DIABETES MELLITUS. Introduction: Diabetic retinopathy (DR) is an important complication of diabetes and one of the major causes of blindness in adults. Studies in animals showed protective effects of vitamin D against DR. That suggests the hypothesis that vitamin D deficiency may be involved in the pathogenesis of DR. However, there are few studies evaluating the association between vitamin D deficiency and DR in individuals with type 1 diabetes mellitus. Objective: To evaluate the association between vitamin D deficiency and retinopathy in patients with type 1 diabetes mellitus. Methodology: This is a cross-sectional study with type 1 diabetic patients. Patients were allocated into two groups: (1) without DR and (2) with DR. Vitamin D deficiency was defined by levels of 25(OH)D<20 ng/mL. Anthropometric data, gender, age, duration of diabetes, glycated hemoglobin (HbA1c), lipid profile and creatinine were analyzed. Results: The present study consisted of 40 patients, from which 16 patients (40%) had DR and 4 patients (10%) had vitamin D deficiency. The proportion of patients with vitamin D deficiency was bigger in the group of subjects with DR (12.5%) when compared to the group of subjects without DR (8.33%). However, this difference was not statistically significant (P=0.67). Discussion: The present findings differed from the data published in the literature, where the majority of studies suggest an association between DR and vitamin D deficiency. Vitamin D seems to inhibit the onset and progression of DR through its anti-inflammatory and antiangiogenic properties. However, there are few studies on this topic and the majority are cross-sectional studies. Therefore, the influence of vitamin D on DR is not yet confirmed. Conclusions: Our study did not show a statistically significant association between vitamin D deficiency and retinopathy in patients with type 1 diabetes. The role of vitamin D in the pathogenesis of DR is unclear and more studies are necessary to clarify this relationship.