Weight Change Trajectories After Incident Lower-Limb Amputation

Objective: To characterize weight change after amputation by identifying typical weight trajectories in men with incident lower-limb amputation (LLA) and describing characteristics associated with each trajectory.

Design: Retrospective cohort study and analyzed using group-based trajectory modeling.

Setting: Administrative data.

Participants: Veterans who were men (N=759), living in the Northwest United States, and who had an incident toe, foot, or leg amputation between 1997 and 2008 and at least 18 months of amputation-free survival thereafter.

Interventions: Not applicable.

Main outcome measures: Postamputation weight and body mass index change.

Results: The mean weight at baseline was 91.6±24 kg (202±53 lb), and average follow-up was 2.4 years. We identified 4 trajectory groups for weight change: weight loss (13%), stable weight (47%), slow weight gain (33%), and rapid weight gain (7%). Men with a toe or foot amputation most frequently were assigned to the stable weight group (58%), whereas men with transtibial or transfemoral amputations were most commonly assigned to the slow weight gain group (42% each). Men who died during follow-up were more likely to be assigned to the weight loss group (24%) than men who did not die (11%).

Conclusions: We identified distinct weight change trajectories that represent heterogeneity in weight change after LLA. An improved understanding of factors predictive of weight gain or loss in people with LLA may help better target rehabilitation and prosthetic prescription. Additional research is needed to fully understand the relation between weight change and health status after amputation.