Nutritional status in rheumatoid arthritis. Effects of disease activity, corticosteroid therapy and functional impairment.

Sixty-five patients with rheumatoid arthritis (RA) (mean age 37.2 years) were compared with 71 controls (mean age 33.8 years). Anthropometric measurements included body diameters and skin-fold thickness at multiple sites, while biochemical markers of nutritional status included serum albumin, thyroxine-binding pre-albumin and retinol-binding globulin levels. None of the RA subjects was outside the range that extended 2 standard deviations above and below the normal control values for lean body mass. Discriminant analysis showed that corticosteroid therapy did not significantly influence skinfold thickness in RA. A combination of bi-acromial and bi-ankle diameters had a sensitivity of 70% and a specificity of 72% in differentiating the RA group, in whom disease activity had a greater effect on body diameters than corticosteroid therapy did. Differences related to functional impairment were a manifestation of disease activity rather than a direct effect on skinfold thickness or body diameters. According to anthropometric measurements in ambulant patients, RA does not result in malnutrition in young individuals.