A clinical study of the association and risk factors for lower limb neuropathy in patients with diabetic retinopathy

PURPOSE: Association of peripheral neuropathy with diabetic retinopathy is known but the relationship of preclinical neuropathy with various grades of retinopathy is not well documented. This study evaluated the association of preclinical peripheral neuropathy using nerve conduction studies with various grades of retinopathy. METHODS: Cases of diabetic retinopathy of various grades but asymptomatic for peripheral neuropathy underwent nerve conduction studies of the lower limbs using Caldwell machine and Sierra wave software. The risk factors for retinopathy and association of neuropathy with various grades of retinopathy were analyzed by bivariate and multivariate regression analysis. RESULTS: The overall prevalence of neuropathy was 75.6% (sensory 58.54% and combined motor and sensory 17.1%) with increase in prevalence with increase in severity of retinopathy. Duration was positively associated with neuropathy (OR = 1.13, 95% CI = 1.02–1.24; P = 0.012); moderate nonproliferative diabetic retinopathy (NPDR) (OR = 5.60, P = 0.002), severe and very severe NPDR (OR = 5.8, P = 0.041), and PDR (OR = 16.05, P = 0.000) were significantly at higher risk for having neuropathy as compared to mild NPDR. CONCLUSION: Duration and severity of retinopathy are important risk factors for peripheral neuropathy. There is a high prevalence of peripheral neuropathy among diabetics with retinopathy especially with severe grades, when neuropathy is diagnosed using nerve conduction studies.