Corticosteroids are used to treat a variety of medical conditions. Although a valuable and necessary treatment option in some patients, long-term corticosteroid use does have some adverse effects. One such adverse effect is bone loss. The amount of bone loss in patients taking corticosteroids is directly related to the dosage and duration of treatment, with the most rapid loss occurring within the first six months of therapy. This bone loss places patients who are treated with corticosteroids at risk for osteoporosis and subsequent fractures. Cohen and associates studied the efficacy of risedronate in the prevention of bone loss in patients who are taking long-term corticosteroid therapy.

The study was a multicenter, randomized, placebo-controlled, parallel group trial. Ambulatory adult patients with a variety of rheumatologic, pulmonary or skin conditions who were taking corticosteroid therapy were enrolled in the study. Patients had to be taking corticosteroids for at least three months to qualify for the study. Patients were randomly assigned to placebo or treatment groups. The treatment group received 2.5 or 5 mg of risedronate daily. All patients enrolled in the study also received 500 mg of elemental calcium per day. Lumbar spine bone mineral density (BMD) was measured at the beginning and at the completion of the trial. Proximal femur BMD and vertebral fractures were also recorded.

The lumbar BMD did not change from baseline after 12 months in the risedronate treatment groups, but the placebo group had a bone loss of 3 percent. A decreasing trend was seen in the number of vertebral fractures in the higher dose risedronate group compared to the placebo group. No significant side effects were reported in the risedronate group. The main reported side effects were gastrointestinal, but the number reported was no different than the number reported in the placebo group.

The authors conclude that risedronate is effective in preventing bone loss in patients who have started long-term corticosteroid therapy. It is also well tolerated, with few patients withdrawing from the therapy because of side effects. The main side effects noted were related to the upper gastrointestinal tract, but the authors state this effect could also be related to corticosteroid use.

editor's note: The prevention of osteoporosis has become an important component of general preventive services. Physicians tend to identify women who are peri- or post-menopausal as candidates for antiosteoporotic strategies. Unfortunately, patients who are receiving long-term corticosteroid therapy do not receive preventive measures despite the fact that bone loss can be a significant adverse outcome of corticosteroid use. It is important to remember to evaluate and assess the potential for bone loss in any patient who is initiating long-term corticosteroid therapy and to provide the appropriate preventive strategies. These would include calcium and vitamin D supplementation, along with other medications that can prevent this potentially devastating side effect of corticosteroids.—k.e.m.