Bone mineral density and body composition in ulcerative colitis: A six-year follow-up

Rweduced bone mineral density (BMD) has been reported in ulcerative colitis (UC), but there are no data concerning body composition (fat and lean mass ) in such patients. We used whale body dual-energy X-ray absorptiometry (Ho logic QDR 1000W) at baseline and after 6 years of follow-up to study bone d ensity, and fat and lean mass in 43 outpatients with mild UC (21 men, mean age 36 years, range 21-57 years, and 22 women, mean age 35 years, range 23- 45 years at baseline; disease extent: 2 proctitis, 18 proctosigmoiditis, 8 left colitis, 5 substantial colitis, 10 pancolitis; mean disease duration 8 years, range 2-18 years; no hospitalization; few relapses during the follo w-up) and 111 healthy volunteers matched by sex, age and body mass index. T here were 5 drop-outs. We observed no significant difference in BMD, or fat and lean mass between the male patients and controls at baseline or after 6 years. The total lean mass (Z-score = -3.2, p = 0.001) and trunk lean mas s (Z-score = -2.01, p = 0.03) of the female patients were lower than those of the controls at baseline, whereas their limb lean mass was higher at bot h the beginning and the end of the study (Z-score = 2.14, p = 0.03; Z-score = 2.8, p = 0.004, respectively). At baseline there was a significant negat ive correlation between lifetime steroid intake (enteral and parenteral) an d lumbar spine BMD, obtained as whole body subregion (r = -0.53, p = 0.0006 ). After 6 years there was a significant negative correlation in women betw een whole body and lumbar spine BMD and both steroid intake (r = -0.53, p = 0.01; and r = -0.62, p = 0.003) and the number of relapses (r = -0.49, p = 0.02; and r = -0.44, p = 0.05). Mild UC thus does not represent a risk fac tor for osteopenia per se. The differences in lean mass between the female patients and controls do not seem to be clinically relevant.