Inhaled Glucocorticoids Leads to Dose Related Bone Loss in Premenopausal Women
Inhaled glucocorticoids are commonly prescribed for long-term asthma treatment. Although it has been established that oral glucocorticoid therapy accelerates bone loss, whether inhaled glucocorticoids reduce bone mass has been subject to debate. To examine the relationship between inhaled glucocorticoids and bone loss, Israel et al conducted a three-year prospective cohort study.
The cohort consisted of 109 asthmatic premenopausal women who had no conditions that cause bone loss and who were treated with inhaled triamcinolone acetonide (100ug per puff). Bone density was measured at six months and at one, two, and three years. Results were adjusted for age, the use of inhaled and oral glucocorticoids, and the use of oral contraceptives.
A loss of bone density at both the total hip and trochanter was found to correspond with inhaled glucocorticoid treatment. This decline in bone density was dose-dependent at a rate of 0.00044 gram per square centimeter per puff per year of treatment. The relationship persisted even after excluding from the analysis all women who had received oral or parenteral glucocorticoid therapy during the study. There was no dose-related effect found at the femoral neck or the spine.
Editorial Comment: Osteoporotic fractures are a well documented problem in post-menopausal women and in patients on chronic glucocorticoid therapy. This study demonstrates a clear association of inhaled glucocorticoid use and osteoporosis in pre-menopausal women. This problem is likely to increase with the increase in asthma in the population and the increasing use and availability of more potent inhaled glucocorticoids in treatment. Unfortunately, bisphosphonates are not generally appropriate for use in young women and children. This study supports the use of screening for osteoporosis and the recommendation for weight bearing exercise and calcium and vitamin D supplementation in patients on inhaled glucocorticoids. Further work needs to be done on treatment strategies in this population.