Background Long-term anti-inflammatory therapy with corticosteroids (CS) leads to decreased formation and increased resorption of bone, i.e. to corticoid-induced osteoporosis (CIO). Several recent studies with etidronate, alendronate and risedronate has proven the efficacy of oral bisphosphonate (BP) treatment to increase bone mineral density (BMD) and reduce fracture risk in these patients. Since chronically ill patients with CIO often take multiple oral medications, an injectable BP may improve compliance and therapeutic results.

Methods In a controlled, prospective, comparative two-arm study we treated 105 patients with established CIO (average age 65 years) over three years with either 2 mg ibandronate every 3 months iv (group A) or with a daily dose of 1 mg alfacalcidol orally (group B). All patients received a 500 mg calcium supplement per day. The patients had been on CS for an average time of 8 years. The initial mean BMD values were very low (T-score lumbar spine -3.8, femoral neck -3.1). 91% of the patients had 1 or more prevalent vertebral fractures (average: 3.8 fractures/patient).

Results During the 36 months of observation there was a progressive reduction in back pain in both groups. No relevant adverse events were recorded. Mean BMD at the lumbar spine increased by 14.2% in the ibandronate cases and 2.3% in the 1-alpha group (p < 0.0001). The corresponding changes after 3 years for the femoral neck were 5.1% and 1.6% (p = 0.0005). Six new vertebral fractures per 6 patients were observed in group A and 15 per 12 patients in group B.

Conclusion We conclude that ibandronate is superior to alfacalcidol in the treatment of CIO. The data confirm the very positive effect of BP therapy on the course of CIO. The very good acceptance and excellent compliance with the 3 months bolus therapy in our trial, the scarcity of adverse events and the avoidance of poor intestinal absorption make ibandronate a very interesting alternative to oral BP treatment.