C35-07 Racial/Ethnic Differences in Adherence to Long-Acting Bronchodilators and Risk of Chronic Obstructive Pulmonary Disease Exacerbation

Abstract Rationale Medication non-adherence occurs in over half of patients with chronic obstructive pulmonary disease (COPD) and is associated with an increased risk of severe COPD exacerbation. Although racial/ethnic disparities in adherence and outcomes have been identified across several chronic diseases, less is known about racial/ethnic disparities in adherence and outcomes among patients with COPD. This study sought to examine race/ethnicity as a predictor of medication adherence and measure associations between race/ethnicity and COPD exacerbations after adjusting for adherence. Methods We conducted a cross-sectional study using electronic health record data from a single urban academic medical center. Patients aged 40 years with an active long-acting bronchodilator prescription and an ICD-10 diagnosis code for COPD during any encounter in the previous two years were included in the study. Data for demographics, healthcare encounters for COPD, prescription medications, and medication dispensing history was collected. Medication adherence was calculated as a continuous variable using the medication possession ratio (MPR). Comparisons among groups were made using student’s t tests, ANOVA, or chi-square tests as appropriate. Multivariate linear and logistic regression were used to measure associations between demographic characteristics, adherence, and COPD exacerbations. Results Of the 1,540 patients included in the study, 941 (61%) were Non-Hispanic Black, 301 (20%) were Non-Hispanic White, 142 (9%) were Hispanic, and 156 (10%) were Other race/ethnicity. After adjusting for demographics, adherence to long-acting bronchodilators was significantly lower among Hispanic, Non-Hispanic Black, and Other race/ethnicity patients compared to White patients. The proportion of patients who experienced a COPD exacerbation during the study period was not statistically different between racial/ethnic groups in the unadjusted analysis (p-value 0.111). After adjusting for demographic characteristics and long-acting bronchodilator adherence, Hispanic patients had 51% lower odds of experiencing a COPD exacerbation compared to White patients (OR 0.49, 95% CI 0.28 to 0.85, p-value 0.012). Among Hispanic patients, every 10% increase in long-acting bronchodilator adherence was associated with a 7% decrease in the risk for COPD exacerbation. There were no differences in the risk of COPD exacerbation among Non-Hispanic Black and Other race/ethnicity patients compared to White patients after adjusting for long-acting bronchodilator adherence. Conclusions In this single center study, adherence to long-acting bronchodilators mediated the risk of COPD exacerbation among Hispanic patients but not for other racial/ethnic minorities. Additional research is needed to understand the differential impact of COPD medication adherence on patient outcomes in minoritized groups. This abstract is funded by: National Center for Advancing Translational Sciences and National Institutes of Health through Grant Award Numbers KL2TR002002 and UL1TR002003