Rates and timing of subsequent amputation after initial minor amputation

Area of Science:

• Vascular Surgery
• Diabetology
• Public Health

Background:

• Minor amputations are often precursors to major amputations, particularly in patients with peripheral artery disease (PAD) and diabetes mellitus (DM).
• Understanding the risk factors and rates of subsequent major amputation after initial minor amputation is crucial for improving patient outcomes.
• Existing data on secondary major amputation rates and associated comorbidities remain limited.

Purpose of the Study:

• To determine the rates of major amputation following an initial minor amputation in patients with lower extremity ulcers.
• To identify factors associated with the increased risk of subsequent major amputation in this patient population.

Main Methods:

• A statewide database analysis of patients with PAD, DM, or combined PAD/DM who underwent a minor lower extremity amputation between 2005 and 2013.
• Competing risk Cox proportional hazards modeling was employed to analyze risk factors for subsequent limb loss.

Main Results:

• Patients with combined PAD and DM exhibited the highest rate of subsequent major amputation (6.3%) compared to DM alone (5.2%) or PAD alone (2.1%).
• Revascularization prior to a repeat minor amputation significantly decreased the risk of major amputation (HR, 0.002).
• Treatment in an outpatient setting was associated with a lower likelihood of subsequent major amputation (HR, 0.7).

Conclusions:

• Combined PAD and DM significantly increase the risk of secondary major and minor amputations after an initial minor amputation.
• Approximately half of all limb loss events occurred within one year of the initial minor amputation.
• Timely diagnosis and appropriate medical referral are essential for mitigating limb loss in high-risk patients.