Article

Body composition is important for health screening, but appropriate
methods for unilateral lower extremity amputees have not been validated.
OBJECTIVES: To compare body mass index adjusted using Amputee Coalition equations
(body mass index-Amputee Coalition) to dual-energy X-ray absorptiometry in
unilateral lower limb amputees. STUDY DESIGN: Cross-sectional, experimental.
METHODS: Thirty-eight men and women with lower limb amputations (transfemoral,
transtibial, hip disarticulation, Symes) participated. Body mass index
(mass/height2) was compared to body mass index corrected for limb loss (body mass
index-Amputee Coalition). Accuracy of classification and extrapolation of percent
body fat with body mass index was compared to dual-energy X-ray absorptiometry.
RESULTS: Body mass index-Amputee Coalition increased body mass index (by ~ 1.1
kg/m2) but underestimated and mis-classified 60% of obese and overestimated 100%
of lean individuals according to dual-energy X-ray absorptiometry. Estimated mean
percent body fat (95% confidence interval) from body mass index-Amputee Coalition
(28.3% (24.9%, 31.7%)) was similar to dual-energy X-ray absorptiometry percent
body fat (29.5% (25.2%, 33.7%)) but both were significantly higher ( p < 0.05)
than percent body fat estimated from uncorrected body mass index (23.6% (20.4%,
26.8%)). However, total errors for body mass index and body mass index-Amputee
Coalition converted to percent body fat were unacceptably large (standard error
of the estimate = 6.8%, 6.2% body fat) and the discrepancy between both methods
and dual-energy X-ray absorptiometry was inversely related ( r = -0.59 and r =
-0.66, p < 0.05) to the individual's level of body fatness. CONCLUSIONS: Body
mass index (despite correction) underestimates health risk for obese patients and
overestimates lean, muscular individuals with lower limb amputation. Clinical
relevance Clinical recommendations for an ideal body mass based on body mass
index-Amputee Coalition should not be relied upon in lower extremity amputees.
This is of particular concern for obese lower extremity amputees whose health
risk might be significantly underestimated based on body mass index despite a
"correction" formula for limb loss.

Langue : ANGLAIS