Assessing the outcome of the management of diabetic foot ulcers using ulcer-related and person-related measures

OBJECTIVE - The purpose of this study was to compare different outcome measures in the audit of management of diabetic foot ulcers RESEARCH DESIGN AND METHODS - Data collected prospectively in a consecutive cohort of patients referred to a specialist multidisciplinary foot care clinic between I January 2000 and 31 December 2003 were analyzed. A single index ulcer was selected for each patient and classified according to both the Size (Area and Depth), Sepsis, Arteriopathy, and Denervation [S(AD)SAD] and University of Texas (UT) systems. Ulcer-related outcomes (healing, resolution by ipsilateral amputation or by death, and persisting unhealed) were determined at 6 and 12 months and compared with patient-related outcomes (survival, any amputation, and being free from any ulcer) at 12 months. RESULTS - In 449 patients (63.7% male, mean age 66.7 +/- 13.2 years), 352 (78.4%) ulcers were superficial [S(AD)SAD/UT grade 11 and 134 of these (38.1% of 352) were neither ischemic nor infected. A total of 183 (40.8% of 449) ulcers were clinically infected, and peripheral arterial disease was present in 2 16 patients (48.1%). Seventeen patients (3.8%)were lost to follow-up and were excluded from analysis. Of the ulcers, 247 (55.0% of 449) and 295 (65.7%) healed without amputation by 6 and 12 months, respectively. Median (range) time to healing was 78 (7-364) days. Of all index ulcers, 5.8 and 8.0% were resolved by amputation, and 6.2 and 10.9% by death by the same time points 27.8 and 11.6% persisted unhealed. in contrast, patient-related outcomes revealed that of 449 patients only 202 (45.0%) were alive, without amputation and ulcer free at 12 months. This group had had 272 (1-358) days without any ulcer. A total of 48 (10.7%) patients had undergone some form of amputation, and 75 (16.7%) had died. CONCLUSIONS - These data illustrate the extent to which ulcer-related outcomes may underestimate the true morbidity and mortality associated with diabetic foot disease. It is suggested that when attempts are made to compare the effectiveness of management in different centers, greater emphasis should be placed on patient-related outcome measures.