VALIDATION OF BODY-COMPOSITION ASSESSMENT TECHNIQUES IN THE DIALYSIS POPULATION

Assessment of body composition remains a goal for the routine assessme nt of nutritional status of patients on long-term dialysis. Methods ge nerally available for estimation of body fat in healthy individuals ar e limited by practicality and availability for use in this patient pop ulation. Anthropometry, which is cost effective and easy to perform, i s limited by the lack of appropriate reference standards for patients on dialysis and artifact caused by hydration status. Bioelectrical imp edance affords new opportunities for non-invasive assessment of fluid volume, its distribution, and body cell mass; estimation of fat-free m ass and body fat can be affected by hydration status. Dual x-ray absor ptiometry permits estimation of bone status and fat mass because chang es in hydration status are reflected in estimates of fat-free mass. Ev aluation of validity of techniques for fluid status and body compositi on assessment requires the use of appropriate reference methods and pr oper statistical procedures to examine error, not only between groups, but by individual. Use of body composition assessment methods togethe r with biochemical measurements will enhance the nutritional assessmen t of end-stage renal disease patients on long-term hemodialysis.