REDUCED BONE-MINERAL DENSITY AND UNBALANCED BONE METABOLISM IN PATIENTS WITH INFLAMMATORY BOWEL-DISEASE

Patients with chronic inflammatory bowel diseases (IBD) are at increas ed risk to develop osteopenia and osteoporosis. New parameters for the assessment of bone formation and especially bone resorption have sign ificantly improved the diagnostic procedures to characterize bone meta bolism. Biochemical characterization of bone turnover in IBD patients may provide important information about the pathogenesis of osteoporos is in this patient population. A cross-sectional study was performed. One hundred forty-nine patients (77 men, 52 pre menopausal, and 20 pos tmenopausal women) with IBD (104 with Crohn's disease [CD] and 45 with ulcerative colitis [UC]) underwent clinical, osteodensitometric, and metabolic bone assessment. Bone mineral density was determined by dual energy X-ray absorptiometry. Bone formation (bone alkaline phosphatas e), bone resorption (N-terminal telopeptide of type-I collagen, free d esoxypyridinoline, total pyridinoline, and desoxy pyridinoline), vitam in D, and parathyroid hormone were assessed. Thirty-six percent of pat ients with CD and 32% with UC showed osteopenia, 15% with CD and 7% wi th UC showed osteoporosis. Bone resorption was significantly increased in LED patients compared to normal controls, whereas bone formation d id not show a compensatory increase. Bone formation was even more supp ressed in the subset of patients currently treated with corticosteroid s. Our data confirm the high prevalence of osteopenia and osteoporosis reported in IBD patients. Furthermore, we provide evidence for an inc reased bone resorption accompanied by low bone formation in IBD patien ts. This imbalance of bone metabolism is likely to be one of the reaso ns for increased bone loss in IBD patients.