Purpose: This study had two purposes: to identify characteristics associated with participants' usual weight-bearing activity, and to determine whether weight-bearing activity increased the risk of foot ulcer among persons with diabetes and prior foot ulcer.
Methods: We conducted a prospective cohort study of 400 participants with diabetes and a prior history of foot ulcer. Participants were from the Veterans Affairs Puget Sound Health Care System and Group Health Cooperative in Seattle, WA, and were originally assembled for a randomized controlled trial of footwear. Feet were examined and demographic and health history information was collected at enrollment. Daily weight-bearing activity was reported at enrollment and every 17 wk thereafter for 2 yr. All incident foot lesions were recorded.
Results: Weight-bearing activity was significantly higher among women. Activity was lower among participants who were older, unmarried, or who had a history of congestive heart failure, respiratory disease, stroke, or depression. Activity decreased significantly over the study period but remained similar in those with or without insensate feet. After adjustment for foot-related and health-status characteristics, moderately active participants (4.5-7.4 weight-bearing h.d-1) were at substantially but nonsignificantly reduced risk of foot ulcer compared with "least active" participants (<4.5 weight-bearing h.d-1) (OR 0.50, 95% CI 0.22-1.16). "Most active" participants (>or=7.5 weight-bearing h.d-1) were at significantly reduced risk (OR 0.20, 95% CI 0.04-0.87). Weight-bearing activity exerted similar effects on foot ulcer risk in participants with insensate versus sensate feet .
Conclusion: Increased weight-bearing activity did not increase the risk of foot re-ulceration. Further studies are needed to explore weight-bearing activities that are safe for those with diabetes and insensate feet.