Osteoporosis and osteopenia have been reported frequently in patients with inflammatory bowel disease, most notably Crohn's disease.

Objectives. - To determine the prevalence and risk factors of osteoporosis in patients with Crohn's disease.

Methods. - Prospective study of 56 patients with Crohn's disease, 34 men and 22 women with a mean age of 32 ± 10.4 years (18-54 years) and no history of disorders known to influence bone metabolism. Dual-energy X-ray absorptiometry measurements of bone mineral density (BMD) were obtained at the femoral neck and lumbar spine. A multivariate model including those factors significantly associated with low BMD in the univariate analysis was used to identify independent risk factors.

Results. - Osteoporosis was found in 35.7% and osteopenia in 23.2% of patients. Low BMD was significantly associated with low body mass index (BMI), colonic involvement, and glucocorticoid therapy. Low BMI was an independent risk factor for low BMD. Malnutrition with BMI ≤18 kg/m² was noted in 21 patients, of whom 76.2% had low BMD values, as compared to 48.6% of the patients whose BMI was >18 kg/m² (P = 0.03, odds ratio = 3.4).

Conclusion. - Among risk factors for bone loss in patients with Crohn's disease, malnutrition plays a prominent role that deserves attention when planning treatment programs.