Outcomes before and after treatment escalation to Global Initiative for Asthma steps 4 and 5 in severe asthma

Abstract

Background: Little is known about health outcomes in severe asthma reflected by Global Initiative for Asthma steps 4 and 5.

Objective: To analyze control, risk, economic, and health resource use (HRU) outcomes associated with treatment escalation to Global Initiative for Asthma steps 4 and 5.

Methods: This was a before-vs-after retrospective cohort study of patients (12-75 years old) with asthma newly initiated to omalizumab, high-intensity corticosteroids (HICS; ≥1,000 μg/day of inhaled fluticasone equivalent or oral prednisone), or high-dose inhaled corticosteroid (HDICS; ≥500 to <1,000 μg/day of fluticasone equivalent) using 2002 to 2011 MarketScan data. Poisson regression was used to model HRU outcomes; Tobit regression was used to model medical expenditures.

Results: Of 19,227 patients, 856 initiated omalizumab, 6,926 initiated HICS, and 11,445 initiated HDICS. Use of β-agonist increased for the HDICS and HICS cohorts and decreased for the omalizumab cohort; acute care visits and oral corticosteroid use decreased during follow-up for the HDICS and omalizumab cohorts. Annual health care expenditures, polypharmacy burden, and outpatient visits were high for all cohorts and increased in the follow-up year (baseline to follow-up; general health care expenditures: omalizumab $14,071 to $34,887, HICS $12,030 to $15,557, HDICS $7,570 to $9,826; annual number of asthma prescriptions: omalizumab 11.74 to 19.46, HICS 7.8 to 12.44, HDICS 5.17 to 9.69; outpatient visits: omalizumab 26.79 to 34.06, HICS 18.78 to 21.37, HDICS 15.06 to 16.64).

Conclusion: Omalizumab use was associated with improvements in risk and control accompanied by large increases in expenditures per HRU. Patients on HDICS and HICS showed improvements in risk but worsening control and increased expenditures per HRU. Innovations in disease management and available treatment options are needed to more optimally achieve treatment goals.