Serum Magnesium as a Predictor of Diabetic Retinopathy Severity among Type 2 Diabetic Patients at Kilimanjaro Christian Medical Centre: A One-Year Study 2024-2025

Background: Diabetic retinopathy remains a leading cause of visual impairment among patients with Type 2 diabetes mellitus. While common risk factors such as hyperglycemia and duration of diabetes are well established, the role of micronutrients like serum magnesium in the progression of diabetic retinopathy remains underexplored in sub-Saharan Africa. Aims: To evaluate Serum Magnesium as a Predictor of Diabetic Retinopathy Severity Among Type 2 Diabetic Patients at KCMC Hospital From 2024-2025. Objective: To assess the association between serum magnesium levels and the severity of diabetic retinopathy among patients with type 2 diabetes mellitus attending KCMC. Study Design: Analytical cross-sectional study. Place and Duration of Study: The study was conducted at Kilimanjaro Christian Medical Centre (KCMC), Moshi, Northern Tanzania, between 2024 and 2025. Methodology: An analytical cross-sectional study was carried out at KCMC, involving 201 type 2 diabetic outpatients. Participants underwent fundus examination to assess the severity of diabetic retinopathy, and blood samples were collected for biochemical analysis. Data cleaning and statistical analysis were performed using STATA version 17. Results: A total of 66.7% of participants had diabetic retinopathy, of whom 37.8% had non-proliferative DR (NPDR) and 28.9% had proliferative DR (PDR), while 33.3% had no diabetic retinopathy (NDR). Hypomagnesemia was identified in 14.4% of participants. Patients with low serum magnesium had significantly higher odds of developing more severe stages of DR (AOR = 2.25, p = 0.031). Additionally, a diabetes duration greater than five years was strongly associated with increased DR severity (AOR = 3.05, p = 0.006). Abnormal serum cholesterol was also significantly associated with DR severity (p = 0.011). However, age over 60 years, sex, and HDL levels were not significantly associated with DR severity in the adjusted models. Conclusion: Low serum magnesium levels are significantly associated with increased DR severity and macular edema, suggesting magnesium as a potential modifiable risk factor. These findings support the integration of serum magnesium screening into diabetic care protocols to enhance early detection and prevention of diabetic eye complications in Tanzania.