RS09 - Female Gender Predicts Risk for Above Knee Amputation for Peripheral Arterial Disease Despite Similar Comorbidity Control

Objectives: In patients with peripheral arterial disease (PAD), amputation procedures are associated with significant morbidity and mortality. Patients undergoing above knee amputations tend to experience worse outcomes than those undergoing below knee amputations. Prior studies suggest that women experience worse outcomes when being treated for PAD. We aim to investigate unique demographic and medical predictors of above-knee amputation in female patients.

Methods: We conducted a retrospective review of all lower extremity amputations and amputation-related procedures performed at multiple hospitals within a single health system in the last ten years. Amputation-related procedures included any additional amputations, revisions, or debridement. Patient demographics, comorbidities, and information about medications and specialist visits were collected and outcomes defined as above or below knee amputation. Univariate analysis was performed with chi-square and the student’s t-test.

Results: A total of 1228 cases of major lower extremity amputations were identified in a total of 700 patients (415 male and 285 female patients). A majority (364 patients, 52%) underwent multiple lower extremity amputation-related procedures in the time frame. Female patients undergoing amputation were more likely to be Black or African American (p=0.02, Table I), have an active primary care provider (p=0.04), have Medicare or Medicaid as their primary insurance (p=0.04), and undergo above knee amputation as their first amputation procedure (p < 0.01). Female patients were less likely to require additional amputation-related procedures (p < 0.01). Hemoglobin A1c, active smoking, use of an antiplatelet, use of anticoagulation, use of a statin, and prior listed appointment with cardiology were not significantly different between male and female patients. On multivariate analysis, only female gender was predictive of above knee amputation over below knee amputation (OR 1.47, 95% CI 1.06-2.03).

Conclusions: In our dataset, women were more likely to have a primary care doctor and have statistically similar control of their comorbidities in a population undergoing amputation for PAD. Despite this, women were more likely to undergo an above knee amputation. Further studies are needed to determine if there are additional anatomic or other risk factors responsible for this difference.