Stronger relationship of serum apolipoprotein A-1 and B with diabetic retinopathy than traditional lipids

Aim: Diabetic retinopathy (DR) is the most common preventable cause of blindness where early detection and treatment can be sight-saving. Search for biomarkers of the disease has been relentless. We aimed to determine whether lipoproteins apolipoproteins A1 and B1 (Apo-A1 and Apo-B1) have stronger associations with DR in contrast to conventionally measured low-density lipoprotein (LDL) and high-density lipoprotein cholesterol levels.

Materials and methods: We performed a cross-sectional study and studied 117 patients. Serum lipid profile was assessed by autoanalyzer. Serum Apo-A1 and Apo-B were measured using immunoturbidimetric kit on an autoanalyzer. Apo-B/A1 ratio was calculated. Retinopathy was graded from the digital retinal photographs, taken with nonmydriatic auto fundus camera and classified according to International Clinical DR Disease Severity Scale.

Results: Mean Apo-A1 for mild, moderate, severe retinopathy, and proliferative DR (PDR) shows a significant negative correlation (P = 0.001) with severity of retinopathy. Mean Apo-B for mild, moderate, severe, PDR displayed a significant positive correlation with severity of retinopathy (P = 0.001). Mean Apo-B/A1 for mild, moderate, severe, PDR showed highly significant positive correlation with severity of retinopathy (P < 0.001). In contrast, mean LDL for mild, moderate, severe, PDR showed insignificant association with severity of DR (P = 0.081).

Conclusion: Apo-A1 and Apo-B have a stronger association with the development of DR than traditional lipids and can thus facilitate early detection and treatment of the disease.