Objective: To determine the correlation of serum erythropoietin concentration with diabetic retinopathy in patients with type 2 diabetes mellitus.
Study design: Cross-sectional study. Place and Duration of the Study: Department of Chemical Pathology and Endocrinology, Armed Forces Institute of Pathology (AFIP), Rawalpindi, from July to December 2021.
Methodology: A total of 180 individuals were enrolled in the study and placed in 2 groups as group 1 have 90 cases of type 2 diabetes mellitus and group 2 having 90 age-matched healthy controls. Group 1 was further subclassified into proliferative diabetic retinopathy (PDR) and non-proliferative diabetic retinopathy (NPDR) subgroups by an expert ophthalmologist. Serum erythropoietin, creatinine, blood HbA1c, and haemoglobin were analysed. Correlation between stages of proliferation and serum erythropoietin, creatinine, blood HbA1c, and haemoglobin were analysed. An independent-sample student t-test was applied to compare mean Serum erythropoietin between PDR and NPDR groups. Pearson's correlation was applied among disease severity, and type of retinopathy. A p-value of ≤0.05 was considered significant.
Results: The average age of participants in groups 1 and 2 was 45.88±8.6 and 56.6±10.23 years, respectively. More males (n=60, 66.7%) were noted in cases compared to controls (n=42, 46.7%). serum erythropoietin concentration observed in cases (8.4±1.87 IU/L) was higher than controls (6.50±0.9). The mean serum erythropoietin concentration in PDR (9.35±1.74 IU/L) was significantly greater than that in NPDR (7.3±1.38 IU/L, p <0.001). The serum concentration of erythropoietin in group 1 increased linearly with the severity of the disease (r=0.103).
Conclusion: Serum erythropoietin concentrations increased in uncontrolled type 2 diabetics more so in proliferative retinopathy cases, and increased with disease severity.
Key words: Erythropoietin, Diabetic retinopathy, Proliferative diabetic retinopathy.