A controlled study of bone mineral density in patients with inflammatory bowel disease

To assess the prevalence of and risk factors for low bone mineral density in inflammatory bowel disease (IBD), 152 IBD patients and 73 healthy controls were studied. Sixty seven patients had ulcerative colitis, 78 had Crohn's disease (52 of them (66.7%) had ileal disease), and seven had indeterminate colitis. Bone mineral density values (g/cm2) measured by dual energy x ray absorbtiometry at the spine (L2-L4), the femoral neck, Ward's triangle, and the trochanter were 1.177, 0.948, 0.850, and 0.838 in the patients and 1.228 (p = 0.034), 1.001 (p = 0.009), 0.889 (NS), and 0.888 (p = 0.012) in the control group, respectively. The type or extent of the disease or previous small bowel resection did not have any significant effect on the bone mineral density values. There was a weak, but statistically significant negative correlation between bone mineral density and the total lifetime corticosteroid dose (in the lumbar spine r = -0.164, p = 0.04, the femoral neck r = -0.185, p = 0.02, Ward's triangle r = -0.167, p = 0.04, and the trochanter r = -0.237, p = 0.003). The patients whose lifetime corticosteroid dose (prednisone/prednisolone) was more than 10 g had especially low bone mineral density (p < 0.05 compared with the groups with no or less than 5 g of corticosteroid). The patients who had never taken peroral corticosteroids did not have decreased bone mineral density. In conclusion, IBD patients have significantly lower bone mineral density values than healthy controls, but the difference is not so great as has been reported previously. Low bone mineral density values in these patients are related to high lifetime corticosteroid doses.