Study Finds Relationship Between Uncontrolled Severe Asthma, Exacerbations and Health Care Resource Use

For patients who have severe asthma, consultation from a specialist is recommended if patients are having difficulty maintaining control over their disease, if they experience 2 or more exacerbations a year, or if they require hospitalization. Failure to meet with specialists may result in worsening or uncontrolled disease. Authors of a study published in The Journal of Allergy and Clinical Immunology: In Practice examined the care that patients with severe asthma received following events indicating uncontrolled disease (EUD) and the relationship of specialized care to disease exacerbations as well as health care resource use and costs. The authors also examined factors that are associated with social disparities.

This observational, retrospective analysis utilized 2 large-scale, real-world claims databases that contained data from commercially insured, managed Medicaid, Medicare Advantage, and Medicare FFS patients. The enrolled patients were aged 12 years and older with severe asthma and appeared in administrative claims data from 2015 to 2020, who were indexed hierarchically.

An uncontrolled severe asthma index date was assigned depending on the severity of each EUD: 1 or more asthma-related hospitalizations (most severe); 2 or more asthma-related emergency department (ED) visits followed by an systemic corticosteroid (SCS) burst within 7 days of the visit; 1 asthma-related, non-ED outpatient visit plus 1 asthma-related ED visit within 12 months, both of which requiring a SCS burst within 7 days following the visit; and 2 or more asthma-related, non-ED outpatient visits within 12 months each followed by an SCS burst within 7 days following the visit (least severe). Patients with severe asthma without recorded EUD were placed in a control group.

In the 12-month period immediately prior to the earliest EUD, patients were required to present an absence of both biologic use and indicators of uncontrolled disease—which was defined as 2 or more asthma-related outpatient visits (including ED visits) with an SCS claim within 7 days following the visit—or 1 or more asthma-related inpatient hospitalizations. Additionally, patients were required to report an absence of comorbid conditions, including cystic fibrosis, pulmonary fibrosis, bronchiectasis, respiratory tract cancer, lung cancer, among others.

A total of 180,736 patients with severe asthma were enrolled in the analysis, of which half (n = 90,368) were controls. The findings demonstrate that the baseline rates of patients who attended specialist visits varied significantly among the groups, with patients in the hospitalization cohort having higher baseline rates (42.5%) than the others (23.2% average rate). Additionally, approximately 50.5% of patients with uncontrolled disease attended at least 1 specialist visit at some point during the post-index period, compared with approximately 22.9% of controls. Further, approximately 27.6% of uncontrolled patients demonstrated evidence of post-index medication escalation, unlike 10.6% of controls.

The study authors also observed that 35% to 51% of patients with severe asthma with an EUD had no evidence of either a specialist visit or medication escalation on or after the event. In the 2 or more ED visits group, approximately 50% of the patients did not have an escalation of care during the follow-up period, which was consistent across different payer types. Additionally, approximately 41% of Black patients had no evidence of a specialist visit or medication escalation following the uncontrolled event, compared with 38% of Hispanic patients, 33% of non-Hispanic White patients, and 39% of patients of “other” races (ie, Native Hawaiian or other Pacific Islander, American Indian, Alaska Native). The findings for patients were similar following asthma-related hospitalization (Black: 35%; Hispanic: 32%; non-Hispanic White: 28%; and other: 33.4%).

Further, the majority of patients in each cohort had 1 or more subsequent post-index exacerbation. Overall, the investigators observed that among patients with severe asthma who experienced an EUD, the proportion with 1 or more subsequent exacerbation during the follow-up ranged from 63.9% among patients in the cohort with 2 or more ED visits to 50.7% among patients with one ER visit plus 1 other outpatient visit.

Regarding resource use and costs, the investigators observed that patients who indexed on an asthma hospitalization or had 2 or more asthma-related ED visits suffered an approximate 146.6% and 68% higher costs, respectively, than patients in the control group. Pharmacy costs made up about 32.4% of the total health care and asthma-related expenditures for between 13.1% and 29.1% of total costs for patients.

The authors note that there are several limitations to the study, including missing data potentially resulting in misclassification bias; the assumption that patients were taking medications as prescribed; the lack of information on medication adherence prior to EUDs; and the lack of generalizability due to patients only being insured with Medicare Advantage, Medicare FFS, Medicaid, as well as other commercial insurances. Additionally, the authors note that the follow-up for the study occurred in 2020 and overlapped with the COVID-19 pandemic, resulting in a potential underrepresentation of health care use.

The researchers believe that this study is the first to describe the incidence of guideline-recommended specialist visits and medication escalation among patients from the US who have uncontrolled severe asthma based on exacerbations that require health care use. Finally, they emphasize that efforts need to come from the collaboration between health care providers, policymakers, and stakeholders in order to implement strategies that will provide all patients with severe asthma with the best possible care.

Reference

Carr T, Tkacz J, Chung Y, et al. Gaps in Care Among Uncontrolled Severe Asthma Patients in the United States. The Journal of Allergy and Clinical Immunology: In Practice. 2024. doi:10.1016/j.jaip.2024.03.018