A pooled data analysis on the use of intermittent cyclical etidronate therapy for the prevention and treatment of corticosteroid induced bone loss

Objective. To conduct a pooled data analysis in a group of patients defined by sex, menopausal status, and underlying disease in order to examine the effect of intermittent cyclical etidronate in the prevention and treatment of corticosteroid induced osteoporosis. Methods. We selected 5 randomized, placebo controlled studies that examined the efficacy of intermittent cyclical etidronate therapy in which the raw data were available for analysis. Three were prevention studies and 2 treat ment studies. The primary outcome was the difference between treatment grou ps in the percentage change from baseline in lumbar spine bone density. Sec ondary outcomes included the difference between treatment groups in the per centage change from baseline in femoral neck and trochanter bone density, a nd vertebral fracture rates. Results. Results are separately pooled for the prevention and treatment stu dies. The prevention studies had significant mean differences (95% CI) betw een groups in mean percentage change from baseline in lumbar spine, femoral neck, and trochanter bone density of 3.7 (2.6 to 4.7), 1.7 (0.4 to 2.9), a nd 2.8% (1.3 to 4.2) after one year of treatment, in favor of the etidronat e group. The treatment studies displayed a mean difference between groups i n mean percentage change from baseline in lumbar spine bone density of 4.8 (2.7 to 6.9) and 5.4% (2.5 to 8.4) after one and 2 years of therapy. In the prevention studies, a reduced fracture incidence was observed in the etidr onate group compared with the placebo group (relative risk 0.50; CI 0.21 to 1.19). Conclusion. Etidronate therapy was effective in preventing bone loss in the prevention studies and in preventing or slightly increasing bone mass in t he treatment studies. A fracture benefit was observed in postmenopausal wom en treated with etidronate in the prevention studies.