Outcome of ischaemic foot ulcers in patients with diabetes, with or without revascularization
The aim of the studies presented in this thesis was to study patients with diabetes and severe peripheral arterial disease (PAD) in regard to outcomes of foot ulcers, factors related to outcomes, and occurrences of new ulcerations and amputations following healing of the initial ulcer.
Patients with diabetes and a foot ulcer, consecutively presenting at a multidisciplinary foot centre, with a systolic toe pressure <45 mm Hg or an ankle pressure <80 mm Hg, were prospectively included, followed up according to a predefined program, and offered vascular intervention when applicable. All patients had continuous follow-up until healing or death, irrespective of the vascular intervention.
In total (n=1,151), 36% of patients healed primarily, 16% healed after minor amputation, 13% healed after a major amputation, and 27% died unhealed. At the end of the study, there was a dropout rate of 5%, and 3% of patients were still in treatment. In patients considered not feasible for revascularization (n=602), 38% healed primarily, 12% healed after minor amputation, 17% healed after major amputation, and 33% died unhealed. Comorbidities, the severity of PAD, and the extent of tissue involvement were strongly related to a low probability for ulcer healing, irrespective of revascularization. Angioplasty or reconstructive vascular surgery increased the probability of healing. The time to revascularization after admittance to a diabetic foot centre was also related to the probability of healing without major amputation.
After healing from a previous ischaemic ulcer, 34% of patients developed a new ulceration in the same foot within the observation time. Twenty-two percent of patients who developed new ulcers had an amputation before healing from the new ulcers. Lesser maximal tissue destruction during the previous ulcer and open reconstructive vascular surgery were related to a lower risk of new ulcerations. Patients with diabetes and ischaemic foot ulcers had a median survival time of 33 months.
In conclusion, this thesis has shown that a substantial number of patients with diabetes, foot ulcers, and severe PAD can heal without a major amputation. The probability of ulcer healing was strongly related to comorbidity, the extent of tissue involvement, and the severity of PAD. Patients with diabetes and ischaemic foot ulcers not feasible for revascularisation are not excluded from healing without major amputation. Not only revascularization per se, but also the timing of revascularization increased the probability of healing without a major amputation. Following healing, these patients had a high risk of developing new ulcers. The extent of tissue involvement of a previous ulcer and reconstructive vascular surgery affected the risk of developing new ulcers.