Temporal association between the incidence of foot ulceration and the start of dialysis in diabetes mellitus.

Background: The aim of this study was to seek a temporal association between the start of renal replacement therapy (RRT) and the first recorded foot ulcer in diabetes.

Methods: Details of all patients with diabetes who had received RRT were extracted from the renal database and were cross-checked with the database held in the specialist foot clinic. The date of onset of first registered foot ulcer was taken and compared with the date of onset of RRT. The self-controlled case-series method was used to establish any significant temporal association between the start of RRT and first recorded foot ulcer in diabetes.

Results: Of 466 patients with diabetes dialysed at our hospital since 1976, 94 (20.2%) were recorded as having at least one foot ulcer, with 15 of these undergoing major amputation. Incidence ratios (IRs) were calculated for 90 patients in whom complete data were available. A close temporal association was observed between the start of RRT and the first recorded foot ulceration: IR (95% CI) in the first and between the second and fifth years of dialysis were 3.35 (95% CI: 1.59-7.04), and 4.56 (2.19-9.50), respectively, relative to the time before dialysis. The IR for major amputation was 31.98 (2.09-490.3) in the first year and 34.01 (1.74-666.2) in the second to fifth years.

Conclusion: These results reveal a close relationship between the onset of RRT in diabetes and the onset of foot ulceration, and confirm the high incidence of amputation in those on dialysis. Urgent steps should be taken to coordinate all aspects of diabetes foot care before and after the start of RRT.