LOS ANGELES — Patients with elevated immunoglobulin E levels had escalated rates of health care use, which consisted of emergency care and medications such as chronic oral corticosteroids, according to study findings presented at the American Academy of Allergy, Asthma & Immunology Annual Meeting.
“Allergic asthma comprises a well-recognized phenotype, marked by increased levels of immunoglobulin E (IgE),” study researcher Evgeniya Antonova, MS, PhD, of Genentech Inc., South San Francisco, California told Healio.com/Allergy. “We aimed to estimate to what extent elevated IgE values might be associated with poor asthma outcomes in real-world settings.”
Antonova and colleagues performed a cross-sectional analysis of 652 asthma patients (average age 52.4 years; 70.7% women), of whom 43.9% (n = 286) had elevated IgE at least once.
“We used electronic medical records linked with health care claims data to investigate whether IgE greater than 75 IU/mL — elevated IgE — was associated with poor asthma outcomes,” Antonova said.
Results indicated that allergen immunotherapy (18.2% vs. 10.9%; P = .008), chronic oral corticosteroids (33.6% vs. 26%; P = .034), long-acting beta agonists (64.0% vs. 56%, P = .04) and omalizumab (8.7% vs. 3.6%; P = .005) were more likely used in patients with elevated IgE than low IgE.
“Asthma patients who had elevated IgE at least once during the study period also used much higher doses of oral corticosteroids than their counterparts who did not have elevated IgE: 738 mg vs. 494 mg of annual prednisone-equivalent exposure; P = .013,” Antonova told Healio.com/Allergy.
The researchers evaluated the outcomes of asthma exacerbations and asthma-related health care use including medications, office and ED visits, and hospitalizations by using t-test or Chi-square tests.
“After adjusting for differences in demographic characteristics and overall health status, elevated IgE patients experienced more asthma exacerbations (1,331 vs. 989 per thousand patients-years; P = .004), asthma-related ED visits (30 vs. 3 per thousand patient-years; P = .002) and asthma-related office visits (2,280 vs. 1,540 per thousand patient-years; P = .013) than their counterparts without elevated IgE status,” according to Antonova. “In contrast, the overall health care resource was similar between the two groups.”
No difference of high-dose inhaled corticosteroid use was found between elevated IgE and low IgE patients (36.7% vs. 35.5%, P = .753).
“These analyses suggest that allergic asthma, characterized by elevated IgE values, is associated with more exacerbations, higher doses of [oral corticosteroids] and more frequent asthma-related health care resource use than asthma not accompanied by the elevated IgE status,” Antonova said.
However, Antonova noted, “Results of this research should be interpreted in lights of its limitations. These data were derived from a subset of insurance claims linked with EMR data and may not be representative of patients without commercial insurance, or of insured patients without EMR data. IgE data are subject to testing bias: patients suspected of having elevated levels would be more likely to have this test.”— by Alaina Tedesco
Antonova E, et al. Abstract 27. Presented at: American Academy of Allergy, Asthma & Immunology Annual Meeting; March 4-7, 2016; Los Angeles.
Disclosure: Dr. Antonova reported that Genentech provided funding for the study.