MULTICENTER STUDY OF THE INCIDENCE OF AND PREDICTIVE RISK-FACTORS FORDIABETIC NEUROPATHIC FOOT ULCERATION

OBJECTIVE-To investigate longitudinally prognostic factors for foot ul ceration in a large population of diabetic patients with established n europathy. RESEARCH DESIGN AND METHODS-A double-blind multicenter stud y of a potential new agent for diabetic neuropathy provided the opport unity for this 1-year investigation since intervention demonstrated no efficacy in the condition. A total of 1,035 patients with NIDDM and I DDM were included. inclusion criteria were vibration perception thresh old (VPT) at the great toe greater than or equal to 25 V in at least o ne foot and less than or equal to 50 V in both feet, normal peripheral circulation, and no previous foot ulceration. VPT and clinical compon ents of the Michigan diabetic polyneuropathy (DPN) score were assessed at baseline and subsequent visits. RESULTS-After 1 year, the incidenc e of first foot ulcers for the total population nas 7.2%. Neuropathy p arameters were the same between the treatment and placebo groups at ba seline and were unchanged at 1 year; therefore, baseline data were com bined for multiple regression analysis. VPT, age, and Michigan DPN sco res for muscle strength and reflexes were significant independent pred ictors for first foot ulceration (P < 0.01). For each 1-U increase in VPT values at baseline, the hazard of the first foot ulcer increased b y 5.6%. Similarly for each 1-U increase in muscle strength and reflex components of the Michigan DPN scores, the hazard of the first foot ul cer increased by 5.0%. CONCLUSIONS-Tests of VPT and Michigan DPN score s for muscle strength and reflexes are useful clinical predictors for foot ulceration in diabetic patients with established neuropathy. The rate of subsequent ulceration in the following year was alarmingly hig h, however, despite standardized foot care education at baseline and r egular follow-up visits.