Systemic and inhaled corticosteroids used continuously or in high doses increase the risk of osteoporosis and fracture, but the impact of prolonged use of topical corticosteroids is unknown. Researchers investigated whether the use of potent or very potent topical corticosteroids in adults is associated with these same adverse events.

The cohort study included 723,251 adults (52.8% women; mean age, 52.8 years) who had filled prescriptions for at least 200 g of mometasone furoate or the equivalent. After adjustment for age, sex, and other variables, the researchers found significant associations between any exposure to potent or very potent topical corticosteroids and osteoporosis and major osteoporotic fracture. The risk increased with increasing dose. For osteoporosis, hazard ratios were 1.06 for exposure to 500 to 999 g, 1.09 for exposure to 1,000 to 1,999 g, 1.10 for exposure to 2,000 to 9,999 g, and 1.24 for exposure to at least 10,000 g; for major osteoporotic fracture, the hazard ratios were 1.01, 1.05, 1.10, and 1.27, respectively.

The relative risk of osteoporosis and major osteoporotic fracture increased by 3% for every doubling of the topical corticosteroid dose. The population-attributable risk of any exposure versus nonexposure was 4.3% for osteoporosis and 2.7% for major osteoporotic fracture. The absolute risk to the average topical corticosteroid user, however, was low.

The authors note that because the unexposed control group received doses of 200 g to 499 g of potent or very potent topical corticosteroids, the true effect of these agents may have been underestimated in this study. Also, data on the anatomical locations where topical corticosteroids were applied weren't available, and the results of this study didn't distinguish between ointments and creams, which can have different effects.

The researchers note that corticosteroid-sparing treatment or prophylaxis for osteoporosis may be considered when patients require potent treatment on large body surfaces for prolonged periods.