Introduction: There has been inconsistent evidence on the association between use of inhaled corticosteroids (ICS) and increased risk of nonvertebral fractures in patients with asthma or chronic obstructive pulmonary disease (COPD). In a large population-based study in the United Kingdom, we estimated the association between fluticasone propionate/salmeterol fixed-dose combination (FSC) and other ICS use and nonvertebral fracture incidence among patients with COPD.
Methods: We identified a cohort of patients aged ≥ 45 years with COPD in the General Practice Research Database (GPRD) between 2003 and 2006. We used a nested case-control design to estimate the odds of incident nonvertebral fractures associated with prior prescriptions of FSC and other ICS, applying conditional logistic regression and controlling for potential confounders. Exposure to FSC and other ICS was assessed by recency, duration, and number of prescriptions. Average daily dose was defined as low, medium, high, or very high using fluticasone propionate equivalents.
Results: We identified 1523 nonvertebral fracture cases among 53 191 patients with COPD at risk in the cohort. Use of FSC in the year prior to the index date was associated with a statistically significant increase in the odds of nonvertebral fractures (odds ratio [OR], 1.25; 95% confidence interval [CI], 1.07-1.47); however, there was no increase in the odds of nonvertebral fractures for other ICS use (OR, 1.12; 95% CI, 0.97-1.30). When examining results by the recent use of prescriptions, an exposure that occurred farther from the index date was associated with a significant increase in nonvertebral fracture (26-52 days prior OR, 1.36; 95% CI, 1.04-1.77; 53-365 days prior OR, 1.39; 95% CI, 1.07-1.78), whereas categories of more recent use (0-12 days prior or 13-25 days prior) were not associated with nonvertebral fractures relative to no FSC use. No pattern of association between increasing levels of FSC or other ICS average daily dose and increased odds of nonvertebral fracture was observed.
Conclusion: We did not observe a consistent association between prescriptions of FSC or other ICS in terms of recent use or average daily dose in the prior year and increases in the odds of nonvertebral fractures in patients with COPD, although ever use of FSC was associated with a slight elevation in the odds.