Lowering body mass index cutoffs better identifies obese persons with spinal cord injury

Cross-sectional, non-experimental design.

(1) Determine the sensitivity and specificity of the general population body mass index (BMI) cutoff for obesity (30 kg m(-2)) in a representative sample of persons with spinal cord injury (SCI); (2) develop a more sensitive BMI cutoff for obesity based on percentage of fat mass (%FM) and C-reactive protein (CRP).

Ontario, Canada.

A total of 77 community-dwelling adults with chronic SCI underwent anthropometric measures (%FM by bioelectrical impedance analysis, length, weight, BMI (kg m(-2))) and provided blood samples to determine CRP. Sensitivity and specificity analyses, piecewise regression, non-linear regression, and receiver-operator characteristic curves were used to determine new BMI cutoffs.

A BMI cutoff of 30 kg m(-2) failed to identify 73.9% of obese participants vs 26.1% at a lowered cutoff of 25 kg m(-2). BMI cutoffs based on risk levels of the %FM and CRP considered together ranged from 22.1 kg m(-2)-26.5 kg m(-2).

People with chronic SCI and BMI values >22 kg m(-2) should be considered as being at high risk for obesity and obesity-related chronic diseases.

Canadian Institutes of Health Research.