Comparison of three systems of classification in predicting the outcome of diabetic foot ulcers in a Brazilian population

Abstract

The aim was to compare three ulcer classification systems as predictors of the outcome of diabetic foot ulcers: the Wagner, the University of Texas (UT) and the size (area, depth), sepsis, arteriopathy, denervation system (S(AD)SAD) systems in a specialist clinic in Brazil. Ulcer area, depth, appearance, infection and associated ischaemia and neuropathy were recorded in a consecutive series of 94 subjects. A novel score, the S(AD)SAD score, was derived from the sum of individual items of the S(AD)SAD system, and was evaluated. Follow-up was for at least 6 months. The primary outcome measure was the incidence of healing. Mean age was 57.6 years; 57 (60.6%) were male. Forty-eight ulcers (51.1%) healed without surgery; 11 (12.2%) subjects underwent minor amputation. Significant differences in terms of healing were observed for depth (P=0.002), infection (P=0.006) and denervation (P=0.002) using the S(AD)SAD system, for UT grade (P=0.002) and stage (P=0.032) and for Wagner grades (P=0.002). Ulcers with an S(AD)SAD score of <or=9 (total possible 15) were 7.6 times more likely to heal than scores >or=10 (P<0.001). All three systems predicted ulcer outcome. The S(AD)SAD score of ulcer severity could represent a useful addition to routine clinical practice. The association between outcome and ulcer depth confirms earlier reports. The association with infection was stronger than that reported from the centres in Europe or North America. The very strong association with neuropathy has only previously been observed in Tanzania. Studies designed to compare the outcome in different countries should adopt systems of classification, which are valid for the populations studied.