Survival after lower-extremity amputation

BACKGROUND: Lower extremity amputation has long been considered an end-of-life event and it is unclear if survival after amputation has improved over time. STUDY DESIGN: A retrospective cohort comprised from a statewide, hospital discharge database was used to determine if survival after amputation improved with time. The cohort included all patients (older than 18 years) with nontraumatic, lower extremity amputations 0 987 to 2000). Survival analysis was used to determine the adjusted hazard ratio of survival as it related to the era of amputation. RESULTS: A total of 13,807 patients (mean age +/- SD, 67 +/- 15, 58.5% men) underwent amputation. The gender and age standardized frequency of amputation remained essentially stable, with a 0.01% increase per year (95% CI, 0.006-0.01%). During followup, 49.2% (6,795/13,807) of patients died, with significantly (p < 0.001) worse outcomes for more proximal levels of amputation. After controlling for potential confounders, including age, gender, level of amputation, comorbid illness, emergency status of procedure, hospital type, and payer of the procedure, patients undergoing amputation in more recent years (1995 to 2000) had a 28% lower hazard of dying (hazard ratio 0.72 [95% CI, 0.67-0.77%) during the study period than those undergoing operation before 1995. Thirty-day survival did not improve by era (p = 0.2), although 1- and 5-year survival after amputation was significantly greater for all levels of amputation (p < 0.001). CONCLUSIONS: Although 30-day survival associated with amputation has remained stable in the state of Washington over the past 14 years, longterm survival after amputation has improved considerably with time. The reasons underlying this improvement should be explored so that further gains may be achieved.