Long-term effects of inhaled corticosteroids on bone mineral density in older women with asthma or COPD: a registry-based cohort study

The SummaryWe assessed the association between long-term inhaled corticosteroid (ICS)use and bone mineral density (BMD) in older women with chronic respiratory disease. Women with >50% adherence to ICS use had very slightly accelerated BMD loss at the total hip compared with those with lower or ICSuse.IntroductionThis study evaluated the impact of long-term ICS therapy on bone loss in older women with asthma or chronic obstructive pulmonary disease (COPD).MethodsWe used a population-based bone densitometry registry linked with administrative health data covering the province of Manitoba, Canada (1999-2013), to identify women aged >40years who had diagnosed asthma or COPD. ICS exposure was defined as cumulative dispensed days and medication possession ratio (MPR). Associations were examined both cross-sectionally and longitudinally, and results were covariate adjusted.ResultsAmong 6561 women with asthma and/or COPD (mean age 65years [SD=11]), compared to no ICS treatment, those in the highest tertile of prior ICS use (720days) had lower BMD at the femoral neck (-0.09 T-score, 95% CI -0.16, -0.02) and total hip (-0.14 T-score, 95% CI -0.22, -0.05), but not at the lumbar spine. Over a mean of 5years of follow-up, the highest tertile of ICS exposure (MPR >0.5) was associated with a -0.02 SD/year (95% CI -0.04, -0.01) greater decline in total hip BMD relative to non-users, with no significant effect at the femoral neck or lumbar spine. Middle and lower tertiles of ICS use were not associated with baseline or longitudinal change in BMD.ConclusionsThe highest tertile of ICS use was associated with a slightly lower hip BMD at baseline and slightly greater reduction in total hip BMD over time in older women with asthma or COPD. No adverse effects on BMD were seen from low to moderate ICS exposure.