Cyclic etidronate in the prevention of bone loss in corticosteroid-treated primary biliary cirrhosis - A prospective, controlled pilot study

Background: Recently, promising disease modifying effects of low dose corticosteroid treatment in primary biliary cirrhosis have been reported. However, steroid-induced bone loss constitutes a potential drawback of this treatment option. Aim: To assess whether etidronate can reduce bone loss during corticosteroid treatment. Methods: Twelve primary biliary cirrhosis patients (all Child-Pugh Class A), treated with prednisone in the context of a 1-year placebo-controlled pilot study with prednisone (maintenance dose 10 mg daily), and azathioprine (50 mg daily), were randomized to receive either cyclical etidronate (400 mg daily, during 2 weeks) alternated with calcium 500 mg daily during 11 weeks or calcium alone. All patients had been receiving ursodeoxycholic acid during at least 1 year and this treatment was continued. Bone mass was measured in the lumbar spine and the femoral neck by dual energy X-ray absorptiometry before and after 3 and 12 months of treatment, Markers of bone formation (serum osteocalcin, procollagen-I-propeptide) and bone resorption (urinary deoxypyridinoline and calcium) were also monitored. Results: The mean lumbar bone mineral density did not significantly change in the patients taking etidronate+calcium, in contrast to patients treated with calcium alone (+0.4 vs. -3.0%; p=0.01). Changes in femoral bone mineral density and markers of bone turnover did not significantly differ between both groups, No adverse effects of etidronate were noted. Conclusions: Cyclical etidronate appears to prevent bone loss associated with prednisone treatment in patients with primary biliary cirrhosis. These preliminary results encourage the further evaluation of long term prednisone treatment and concurrent bisphosphonate therapy in primary biliary cirrhosis.