TOTAL-BODY CALCIUM IN WOMEN WITH INFLAMMATORY BOWEL-DISEASE TREATED WITH HORMONE REPLACEMENT THERAPY

Objective: To examine changes in total body calcium and radial and spinal bone mineral content in peri- and postmenopausal women with inflammatory bowel disease treated with hormone replacement therapy. Design: Follow-up measurements were made over a mean of 2.1 years (range 1.9-2.3 years). Methods: Sixteen women, with a mean age of 47 years (range 41-57 years), with inflammatory bowel disease underwent repeat measurements of bone density. Of the 16 women, 10 were postmenopausal, while six were perimenopausal. All patients were given oral conjugated oestrogen 0.625 mg daily; the 13 patients who had not had a hysterectomy were also given cyclic progestogen, 150 mu g norgestel, for 12 days each month. Total body calcium was measured by prompt gamma neutron activation analysis. Radial cortical bone was measured by single photon absorptiometry and spinal bone by quantitative computed tomography. Results: There was no significant change in total body calcium, radial or spinal bone density during the study. The mean annual change (95% confidence intervals) in total body calcium was +1.87% (-2.2 to +6.0%; P=0.34), in radial bone mineral -0.48% (-1.8 to +0.8%; P=0.44) and in spinal trabecular bone mineral density +0.52% (-0.52 to +2.6%; P=0.60). There were no significant correlations between the rates of change of total body calcium, radial or spinal bone density, or between the rates of change and initial values. There was no clear difference between patients with Crohn's disease (n = 9) and those with ulcerative colitis (n = 7). Conclusions: These results suggest that hormone replacement therapy prevents bone loss in peri- and postmenopausal women with inflammatory bowel disease.