Predicting Basal Metabolic Rate in Men with Motor Complete Spinal Cord Injury
To assess the accuracy of existing basal metabolic rate (BMR) prediction equations in men with chronic (>1 year) spinal cord injury (SCI). The primary aim is to develop new SCI population-specific BMR prediction models, based on anthropometric, body composition and/or demographic variables that are strongly associated with BMR.Methods
Thirty men with chronic SCI (Paraplegic; n = 21, Tetraplegic; n = 9), aged 35 ± 11 years (mean ± SD) participated in this cross-sectional study. Criterion BMR values were measured by indirect calorimetry. Body composition (dual energy X-ray absorptiometry; DXA) and anthropometric measurements (circumferences and diameters) were also taken. Multiple linear regression analysis was performed to develop new SCI-specific BMR prediction models. Criterion BMR values were compared to values estimated from six existing and four developed prediction equationsResults
Existing equations that use information on stature, weight and/or age, significantly (P < 0.001) over-predicted measured BMR by a mean of 14–17% (187–234 kcal/day). Equations that utilised fat-free mass (FFM) accurately predicted BMR. The development of new SCI-specific prediction models demonstrated that the addition of anthropometric variables (weight, height and calf circumference) to FFM (Model 3; r2 = 0.77), explained 8% more of the variance in BMR than FFM alone (Model 1; r2 = 0.69). Using anthropometric variables, without FFM, explained less of the variance in BMR (Model 4; r2 = 0.57). However, all the developed prediction models demonstrated acceptable mean absolute error ≤ 6%.Conclusion
BMR can be more accurately estimated when DXA derived FFM is incorporated into prediction equations. Utilising anthropometric measurements provides a promising alternative to improve the prediction of BMR, beyond that achieved by existing equations in persons with SCI.