Economic Burden Associated with Receiving Inhaled Corticosteroids with Leukotriene Receptor Antagonists or Long-Acting Beta Agonists as Combination Therapy in Older Adults

BACKGROUND: There is a paucity of literature on the health care expenditures associated with different pharmacologic treatments in older adults with asthma that is not well controlled on inhaled corticosteroids (ICS). OBJECTIVE: To compare asthma-related and all-cause health care expenditures associated with leukotriene receptor antagonists (LTRA) versus long-acting beta agonists (LABA) when added to ICS in older adults with asthma. METHODS: A retrospective cohort was constructed using 2009-2010 Medicare fee-for-service medical and pharmacy claims from a 10% random sample of beneficiaries continuously enrolled in Parts A, B, and D in 2009. The sample comprised patients who were aged 65 years and older, diagnosed with asthma, and treated exclusively with ICS + LABA or ICS + LTRA. Outcomes assessed were asthma-related expenditures (medical, pharmacy, and total) and all-cause health care expenditures (medical, pharmacy, and total). Outcomes were measured from the date of the first prescription for the add-on treatment (LABA or LTRA in combination with ICS) after having at least a 4-month “wash-in” period in which patients were receiving no controller, ICS alone, or ICS plus the add-on treatment of the follow-up period. Patients were followed until death, switching to or adding the other add-on treatment, or the end of the study (December 31, 2010). Multivariable regression models with nonparametric bootstrapped standard errors were used to compare all-cause and asthma-related expenditures per patient per month (PPPM) between ICS + LABA and ICS + LTRA users. All models were adjusted for demographics, comorbidities, and county-level health care access variables. RESULTS: The primary analysis included 14,702 patients, of whom 12,940 were treated with ICS + LABA and 1,762 were treated with ICS + LTRA. The mean (SD) follow-up periods were 12.3 (± 5.7) months for the ICS + LABA group and 15.3 (± 5.1) months for the ICS + LTRA group. Adjusted asthma-related expenditures PPPM were $400 for the ICS + LTRA group compared with $286 for the ICS + LABA group (P < 0.001). However, adjusted total all-cause expenditure PPPM was significantly lower for patients treated with ICS + LTRA ($6,087 for ICS + LTRA compared with $6,975 for ICS + LABA, P = 0.029). CONCLUSIONS: Older adults with asthma often experience economic burden from asthma and other chronic illnesses. Compared with ICS + LTRA, ICS + LABA was associated with lower asthma-related expenditures but with higher all-cause expenditures in older adults.