Osteoporosis and fracture risk associated with inhaled corticosteroid use among Swedish COPD patients: the ARCTIC study

The effect of inhaled corticosteroids (ICS) on the risk of osteoporosis and fracture in patients with chronic obstructive pulmonary disease (COPD) remains uncertain. The aim of this study was to assess this risk in patients with COPD. Electronic medical record data linked to National Health Registries were collected from COPD patients and matched reference controls at 52 Swedish primary care centres from 2000 to 2014. The outcomes analysed were the effect of ICS on all fractures, fractures typically related to osteoporosis, recorded osteoporosis diagnosis, prescriptions of drugs for osteoporosis and a combined measure of any osteoporosis-related event. The COPD patients were stratified by the level of ICS exposure. A total of 9651 patients with COPD and 59 454 matched reference controls were analysed. During the follow-up, 19.9% of COPD patients had at least one osteoporosis-related event compared with 12.9% of reference controls (p<0.0001). Multivariate analysis in the COPD population demonstrated a dose–effect relationship, with high-dose ICS being significantly associated with any osteoporosis-related event (risk ratio 1.52 (95% CI 1.24–1.62)), while the corresponding estimate for low-dose ICS was 1.27 (95% CI 1.13–1.56) compared with COPD patients not using ICS. A similar dose-related adverse effect was found for all four of the specific osteoporosis-related events: all fractures, fractures typically related to osteoporosis, prescriptions of drugs for osteoporosis and diagnosis of osteoporosis. We conclude that patients with COPD have a greater risk of bone fractures and osteoporosis, and high-dose ICS use increased this risk further.