Nail Fold Capillary Changes in Diabetes Mellitus and Their Correlation with Diabetic Retinopathy

Background: Nail fold capillaroscopy (NFC) is mainly used in connective tissue diseases (scleroderma, mixed connective tissue disease, and inflammatory myositis). It is not used routinely in the evaluation of diabetic patients and no specific patterns of nail fold capillary changes have been established in diabetes. We studied morphological patterns of nail fold capillaries by video capillaroscope in diabetic patients and their association with diabetic retinopathy (DR). Methods and Material: Fifty diabetics were recruited after informed consent. The mean age of patients was 49.5 ± 10.6 years. Seventeen patients had DR. Capillary length, capillary density, and various morphological parameters were assessed and these parameters were compared between patients with DR and without DR. Results: The most frequent NFC morphological alterations, among diabetics as a group, were tortuous capillaries (56%), giant capillaries (46%), and cross-linked capillaries (44%). Overall, mean nail fold capillary length was reduced in diabetic patients. When individual morphological alterations were compared in patients with DR versus without DR, statistically significant differences were seen for presence of giant capillaries, tortuous capillaries, and avascular areas. On further analysis, mean nail fold capillary length and mean nail fold capillary density were also significantly lesser in patients with DR versus without DR. Conclusions: The presence of nail fold capillary morphological abnormalities among diabetics and a significant association with microangiopathic changes in the retina suggest that microvascular changes can be detected early using a simple, non-invasive office-based method of NFC. More large-scale studies in the future can establish a characteristic pattern for diabetes as seen in systemic sclerosis so that microvascular changes in diabetics can be detected at the earliest with the simple noninvasive method by using NFC.