Validation of methods for estimating HIV/AIDS patients' body fat

OBJECTIVE: To validate different methods for estimating HIV/Aids patients' body fat: total body skinfold thickness, central (trunk) skinfold thickness, peripheral (limb) skinfold thickness, waist circumference (WC) and waist-to-hip ratio (WHR). Dual-energy X-ray absorptiometry (DEXA) and computed tomography of the abdomen (CTA) were used as the gold standard. METHODS: An analysis was done on 15 adult HIV/Aids patients (10 men and 5 women) who were being treated at an Aids clinic at a public university hospital, Sao Paulo, Brazil. Their total subcutaneous fat (TSF) was estimated from the sum of the thicknesses of the biceps, triceps, subscapular, midaxillary, suprailiac, abdominal and medial calf skinfolds. The central subcutaneous fat (CSF) was estimated by summing the subscapular, axillary, suprailiac and abdominal skinfold measurements. The peripheral subcutaneous fat (PSF) was estimated by summing the biceps, triceps and medial calf skinfold measurements. These were compared with Dexa. The WC, WHR and CSF were compared with CTA. In the statistical analysis, the Pearson correlation coefficient (r) and Mann-Whitney test were utilized. RESULTS: There was a correlation between fat mass measured by DEXA and by TSF, CSF and PSF, even after adjusting for age (r>0.80 for all). WC, WHR and CSF presented correlation with total abdominal fat measured by CTA, even after adjusting for age (r>0.80 for all). CONCLUSIONS: The methods for estimating body fat should be chosen according to the type of fat to be evaluated and can be used in research and healthcare services instead of DEXA and CTA for HIV/AIDS patients.

Skinfold thickness; Body constitution; Validity; Acquired immunodeficiency syndrome; HIV; Circunferences

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