BONE-MINERAL DENSITY IS REDUCED IN PATIENTS WITH CROHNS-DISEASE BUT NOT IN PATIENTS WITH ULCERATIVE-COLITIS - A POPULATION-BASED STUDY

Background-Patients with inflammatory bowel disease are at risk of dev eloping metabolic bone disease. Aims-To compare bone mineral density i n patients with Crohn's disease with patients with ulcerative colitis and healthy subjects, and to evaluate possible risk factors for bone l oss in inflammatory bowel disease. Patients-60 patients with Crohn's d isease, 60 with ulcerative colitis, and 60 healthy subjects were inves tigated. Each group consisted of 24 men and 36 women. Methods-Lumbar s pine, femoral neck, and total body bone mineral density were measured by dual x ray absorptiometry (DXA), and Z scores were obtained by comp arison with age and sex matched normal values. Results-Mean Z scores w ere significantly lower in patients with Crohn's disease compared with patients with ulcerative colitis and healthy subjects. Patients with ulcerative colitis had bone mineral densities similar to healthy subje cts. Use of corticosteroids, body mass index (BMI), and sex were signi ficant predictor variables for bone mineral density in Crohn's disease . In ulcerative colitis only body mass index and sex were of significa nt importance. Disease localisation and small bowel resections had no influence on bone mineral density in patients with Crohn's disease. Co nclusions-Patients with Crohn's disease have reduced bone mineral dens ity. Several factors are probably involved, but the reduction is assoc iated with corticosteroid therapy. When studying skeletal effects of i nflammatory bowel disease, patients with Crohn's disease and those wit h ulcerative colitis should be evaluated separately.