Mortality after major amputation in diabetic patients with critical limb ischemia who did and did not undergo previous peripheral revascularization: Data of a cohort study of 564 consecutive diabetic patients

Background

To evaluate the survival after major lower limb amputation, at a level either below (BKA) or above (AKA) the knee, in diabetic patients admitted to hospital because of critical limb ischemia (CLI).

Methods

From January 1999 to December 2003, 564 diabetic patients were consecutively admitted to our Foot Center because of CLI and followed up until December 2005. A revascularization procedure was performed in 537 patients (95.2%): in 420 with peripheral angioplasty, in 117 with peripheral bypass graft. Neither endoluminal nor surgical revascularization was practicable in 27 (4.8%) patients.

Results

Major amputation was performed in a total of 55 (9.8%) patients. Among the clinical and demographic variables evaluated, age was significantly lower (67.3±10.1 vs. 76.7±10.4, P<.001), duration of diabetes was higher (17.1±11.1 vs. 13.4±10.0, P=.013), and current smoking was more frequent (38.5% vs. 25.0%, P<.001) in revascularized amputees. The amputation free median time for revascularized patients was 5.11 months, and for nonrevascularized patients, 0.33 months. The log-rank test for equality of survivor function without amputation between amputees with or without revascularization was 31.76 (P<.001).

Among the 55 amputees, 11 (28.2%) out of the 39 revascularized patients and 13 (81.2%) out of the 16 nonrevascularized patients died. The log-rank test for equality of survivor function was 6.83 (P=.009).

The Cox model performed to evaluate the association between the recorded variables and the mortality showed a significant hazard ratio only with age (hazard ratio for 1 year 1.11, P=.003, confidence interval 1.04–1.19).

Conclusions

Our data suggest that the revascularization allows to postpone the major amputation, and that the survival of revascularized amputees is better than that of nonrevascularized amputated patients. All these data offer further encouragement to revascularize all diabetic patients with CLI.