Peak oxygen consumption in older adults with a lower limb amputation

Objective: To investigate whether the aerobic capacity of older adults who underwent a lower limb amputation is associated with the presence, cause (traumatic or vascular), and level of amputation (transtibial or transfemoral).

Design: Cross-sectional descriptive.

Setting: Human motion laboratory at a rehabilitation center.

Participants: Older subjects (n=36) who underwent lower limb amputation and age-matched, able-bodied controls (n=21). All subjects were able to walk for a minimum of 4 minutes.

Interventions: Not applicable.

Main outcome measure: Peak oxygen consumption (Vo(2)(peak)) was measured using open-circuit respirometry while performing a discontinuous, graded, 1-legged, peak cycle exercise test.

Results: After correcting for age, body mass index, and sex, the multiple linear regression analysis revealed that subjects who underwent amputation had a 13.1% lower aerobic capacity compared with able-bodied controls (P=.021). Differentiation among etiologies revealed that subjects with a vascular amputation had a lower Vo(2)(peak) of 29.1% compared with able-bodied controls (P<.001), whereas traumatic amputees did not differ from able-bodied controls (P=.127). After correcting for etiology, no association between level of amputation and Vo(2)(peak) was found (P=.534).

Conclusions: Older adults who underwent an amputation because of vascular deficiency had a lower aerobic capacity compared with able-bodied controls and people with a traumatic amputation. The level of amputation was not associated with Vo(2)(peak).