Use of the Semmes-Weinstein monofilament in the strong heart study - Risk factors for clinical neuropathy

OBJECTIVE - We used the Semmes-Weinstein 5.07 monofilament to assess the pr evalence of foot insensitivity and its relationship to potential risk facto rs. RESEARCH DESIGN AND METHODS - There were 3,638 American Indian participants from Arizona, North and South Dakota, and Oklahoma who attended a study cl inic on two occasions: baseline and follow-up, 4 years later. Oral glucose tolerance tests were performed at the visits for those who had not previous ly been diagnosed as having diabetes. A total of 2,051 participants Were di agnosed with diabetes before the study or at the subsequent study visits. A l the follow-up visit, participants were tested for their ability to sense the 5.07 (10 g) monofilament at 10 sites of the foot. The prevalence of foo t insensitivity was ascertained, and its relation to characteristics of par ticipants was assessed in both univariate and logistic regression analyses. RESULTS - Diabetic participants had a much higher prevalence of foot insens itivity (defined as greater than or equal to live incorrect responses) than nondiabetic participants (14 vs. 5%, respectively). However, marked foot i nsensitivity was uncommon within the first few years of diagnosis of diabet es. Among the diabetic participants, those diagnosed before study entry had the highest prevalence of foot insensitivity. The prevalence of foot insen sitivity was highest in the Arizona Indians (22 vs. 9% in the Dakotas and 8 % in Oklahoma). In a logistic regression analysis, fool insensitivity was s ignificantly and independently related to center (Arizona versus others), a ge, duration of diabetes, and height. CONCLUSIONS - Marked foot insensitivity is prevalent in the diabetic Americ an Indian population, especially in Indians in Arizona; however, this insen sitivity is apparently uncommon for several years after the diagnosis of di abetes. The data show that Indians with diabetes are particularly vulnerabl e to the risk of foot ulceration and that the diagnostic screening of diabe tes may lead to better prevention of sensory neuropathy and subsequent foot ulceration.