Overuse of reliever inhalers and associated healthcare utilization of asthma patients

Global Initiative for Asthma 2019 guidelines recommend to avoid strengthening patients' reliance on relievers since they increase exacerbation risk. Our aim was to examine the association between reliever inhalers overuse and all-cause healthcare utilization (HCU). A retrospective study among Clalit Health Services (CHS) adult enrollees (n = 977) for 2012-2017. Reliever inhalers overuse was defined as consistent prescription refills of = 3 canisters annually. Adherence to controllers was calculated using the proportion of days covered. HCU included: hospitalizations, diagnostic and surgical procedures, medications, emergency room (ER) visits, and clinic visits. 27% of the study population (n = 264) consistently refilled = 3 relievers prescriptions annually, and had higher adherence to controllers (0.38 vs. 0.24, p < 0.001). Their total 6-year HCU costs were not higher than that of others ($ 5,550 vs. $5,562, p = 0.107). Most HCU components [including hospitalization (p = 0.405) and ER visits (p = 0.884)] were comparable; however, medication costs were higher ($1734 vs. $1504, p < 0.001). A multivariable ordered-logit model revealed that frequent and regular use of relievers was not associated with higher HCU costs (OR = 0.82, 95% CI 0.62-1.09, p = 0.175). Higher adherence to maintenance and reliever therapy (OR = 2.18, 95% CI 1.44-3.28, p < 0.001), other controllers (OR = 3.30, 95% CI 2.11-5.16, p < 0.001), and nebulized SABAs and SAMAs (OR = 1.08, 95% CI 1.02-1.14, p = 0.007) was associated with higher costs. Overuse of reliever inhalers was prevalent and associated with higher adherence to controllers, yet not associated with higher all-cause HCU. This highlights the need to examine the sources of elevated usage in order to develop intervention strategies to optimize pharmaceutical therapy of asthma patients.