Risedronate Therapy in the Treatment of Low Bone Mineral Density in Crohn's Disease

Inclusion Criteria: * Subjects who are 18 years of age, or older. * Crohn's disease, as documented by clinical, radiologic, endoscopic or histologic examination. * Osteoporosis (T score less than -2.5) or osteopenia (T score between -1.0 and -2.5), as determined by dual energy X-ray absorptiometry. Exclusion Criteria: * Known bone disorders other than osteoporosis (such as hyperparathyroidism, Paget's disease, renal osteodystrophy and documented osteomalacia) * Abnormal thyroid function. Those patients on thyroxine replacement must not have had a change in dose in the two months prior to prospective data collection program entry * Clinically significant renal impairment (serum creatinine ≥ 2x normal). * Clinical Short Bowel Syndrome * Patients on total parenteral or enteral nutrition * Spinal anatomy that would not allow adequate assessment of lateral spine using DEXA * Patients who had received: 1. previous bisphosphonate therapy 2. fluoride supplement in the 24 months prior to entry 3. calcium supplements of more than 1.0g/day in the 6 months prior to entry 4. vitamin D supplements greater than 1000 IU/day in the 6 months prior to entry 5. calcitonin in the 3 months prior to entry * Females on hormone replacement therapy who do not agree to continue the therapy for the duration of the prospective data collection program * Men on testosterone who do not agree to continue it for the duration of the prospective data collection program * Pregnancy or women who are breastfeeding