Osteoporosis in patients with inflammatory bowel disease

The prevalence of osteoporosis in inflammatory bowel disease (IBD) has not been accurately established. Using single photon absorptiometry (SPA) and vertebral quantitative computerized tomography (QCT) the authors measured bone mineral content (BMC) in 75 unselected patients with IBD. Osteoporosis was present in 23 (31%). Seven had cortical and trabecular osteoporosis, 11 cortical only and five trabecular only. Three amenorrhoeic premenopausal females had clinically severe osteoporosis and a further 4 had vertebral crush fractures. The median lifetime steroid dose in osteoporotic patients was significantly greater than in patients with normal BMC; most patients with osteoporosis had small bowel IBD with one or more resections. Repeat QCT measurements in 18 patients after one year were unchanged in 12, increased in one and decreased between 10 and 37 mg/ml K2HPO4 in 5 of whom four were receiving steroids. Radial BMC decreased in one patient, increased in one and was unchanged in the remainder. Thus, osteoporosis was present in 30% of these patients, with severe clinical disease in three young females. Rapid spinal trabecular bone loss was demonstrated over the course of one year in some patients. Steroid therapy, amenorrhoe and small bowel IBD with resection appear to be important risk factors