An initially successful healing rate in patients who were hospitalized with diabetic foot ulcers did not lead to comparable long-term outcomes in a prospective study of 94 consecutive patients.
The presence of nephropathy was found to be an important predictor of poorer outcomes, whereas age was an independent predictor of global therapeutic success (GTS), according to a report presented in Diabetes Care.
Of 94 consecutive diabetic patients hospitalized for diabetic foot ulcers between January 1998 and December 2000, 89 (63 men) were successfully followed up for an average of nearly 80 months. The mean age of the patients was nearly 64 years.
Researchers calculated the rates of primary healing, new ulcers, amputations, mortality, and disability, and evaluated the GTS of foot care management (defined as primary healing without recurrence or disability at the end of follow-up). To their knowledge, this was the first time that disability and dependency, which were measured using Katz's index of activities of daily living, were considered as end points of a prospective diabetic foot study, according to Dr. Edouard Ghanassia and colleagues from the Centre Hospitalier Universitaire Montpellier (France).
Primary healing without major amputation occurred in 69 patients (nearly 78%). Amputations were performed in 39 patients (44%), with 30 minor and 9 major amputations; of the minor amputations, 24 occurred in the primary healing group. Ulcers recurred in nearly 61% of patients. Ultimately, 46 patients (nearly 52%) died, including 23 from cardiovascular events.
At the end of the follow-up period, 25 patients (28%) were dependent and 40 patients (nearly 45%) had achieved GTS.
Using multivariate analysis, the researchers found that smoking and renal impairment were independent predictors of healing failure; an age older than 70 years was the only independent predictor of GTS. There were no independent predictors of disability.
Insulin treatment prior to admission was the only predictor of ulcer recurrence, and diabetic nephropathy was the only independent predictor of first amputation. The only independent predictors of cardiovascular mortality were insulin therapy before admittance and renal impairment.
Diabetic nephropathy was also seen to be an important marker of other factors in long-term prognosis, with impaired renal function being an independent predictor of healing failure and all-cause mortality; in conjunction with albuminuria, it was associated with amputations. With use of univariate analysis, popliteal stenosis (diagnosed by Doppler ultrasound) was found to be an independent predictor of amputation, “confirming that vascular involvement in diabetic patients with foot ulcers is particularly important,” the authors stated (Diabetes Care 2008;31:1288-92).
One limitation of the study, according to the authors, was that interview follow-up was conducted by telephone rather than in person.