The impact of racial and ethnic disparities in inhaled corticosteroid adherence on healthcare expenditures in adults with asthma.

The purpose of this study is to determine racial and ethnic disparities with the adherence to inhaled corticosteroids (ICSs) in adults with persistent asthma, and their association with healthcare expenditures. A retrospective, cross-sectional study using the Medical Expenditure Panel Survey (MEPS) 2013-2014 data included patients ≥18 years with persistent asthma. Median medication possession ratio (MPR) was used to dichotomize adherence levels. Multivariate regression analysis was conducted to ascertain the association between adherence and race/ethnicity. Total expenditures and association with adherence were analyzed using a generalized linear model with a log link function and gamma distribution. Unadjusted expenditures were compared after bootstrapping. The average MPR of ICSs for the sample of 277 patients was 0.34. The average MPR level was 0.33 among whites, 0.37 among African-Americans and 0.35 among other minorities. The average MPR was 0.30 among Hispanics, and 0.35 among non-Hispanics. African-Americans were less likely to be adherent than whites (OR 0.95). Hispanics were less likely to be adherent (OR 0.4; CI 0.206-0.777). Higher adherence was associated with significantly higher total health expenditure than lower adherence ($19,223 vs. $12,840 respectively,  < .0001). African-Americans had slightly higher total expenditure compared to whites; however, other minorities had significantly lower health expenditures compared to whites ( = .01). Non-Hispanics spent significantly less on healthcare compared to Hispanics ( = .04). Valuable insight into the economic cost of the disparities as they relate to persistent asthma provides further evidence of possible ethnic inequities that warrant addressing.