Four-year Incident Neuropathy and its Risk Factors in Subjects with Type 2 Diabetes

Objective: The study assessed the four-year incidence of diabetic peripheral neuropathy (DPN) and the risk factors that can predict incident neuropathy in a south Indian population with type 2 diabetes.

Research design and methods: 1175 diabetic individuals were identified with known diabetes at baseline. At baseline, individuals underwent assessment of fasting plasma glucose and HbA1c levels, body mass index, waist-hip ratio, blood pressure, blood cholesterol and lipid levels, and ophthalmic evaluation including visual acuity, specular microscopy of the corneal endothelium, cataract grading and diabetic retinopathy assessment. Subjects were re-examined after four years for the assessment of incident neuropathy; 713 individuals were found eligible at follow-up. The presence of neuropathy was assessed at baseline and at follow-up and was defined as a Vibration Perception Threshold of ≥ 20 Volts.

Results: : The four-year incidence of any neuropathy was 28.4%. Factors predictive of incident diabetic neuropathy were greater age at baseline (OR =1.068), higher body mass index (OR =1.034), presence of diabetic retinopathy (OR =4.879) and lower socioeconomic status (OR =4.841), when adjusted for several potential confounding factors.

Conclusion: The four-year incidence of diabetic neuropathy in a south Indian population with type 2 diabetes is 28% and can be predicted by ophthalmic and clinical variables. These factors may be utilized in the assessment, monitoring and intervention in individuals with diabetes in an effort to prevent or delay the development of diabetic peripheral neuropathy.