A Retrospective Claims Database Study to Clarify Treatment Reality of Asthma Patients Before and After Referral to a Specialist

Abstract

Purpose

Japanese guidelines recommend that patients with uncontrolled asthma be referred by non-specialists to specialists (allergists and/or pulmonologists). This study investigated the reality of clinical practice in asthma patients referred to specialists in Japan.

Patients and Methods

This was a retrospective, observational cohort study of asthma patients in a health insurance claim database (Cross Fact) referred from facilities with non-specialists to those with specialists from January 2016 to December 2018. The referred asthma patients were defined as patients with ≥4 inhaled corticosteroid (ICS)-containing prescriptions during a 1-year baseline period, with an asthma diagnosis, and who had visited a facility with specialists. Asthma exacerbation, maintenance treatment, laboratory tests, and medical procedures before and after referral were analyzed.

Results

Data for 2135 patients were extracted, of which 420 with referral codes were analyzed. The proportion of patients with asthma exacerbations was 50.2% (95% confidence interval [CI]: 45.4–55.1%) before referral and 37.4% (95% CI: 32.7–42.2%) after, a significant decrease (P<0.001; McNemar test). The proportions of patients prescribed ICS alone, long-acting beta-agonists (LABA), and ICS/LABA were lower after referral than before, but the proportions of patients prescribed long-acting muscarinic antagonists (LAMA), ICS/LABA/LAMA, and biologics increased after referral. More asthma-related laboratory tests were performed after referral, and spirometry incidence increased from 16.4% before referral to 51.4% after referral.

Conclusion

This study shows a decrease in asthma exacerbations, change in asthma treatments, and increase in laboratory tests after referral to a specialist, suggesting that referrals to specialists lead to better management of asthma.

Keywords:

• asthma
• database
• referral
• specialist
• symptom exacerbation

Abbreviations

ATC, Anatomical Therapeutic Chemical; COPD, chronic obstructive pulmonary disease; CRP, C-reactive protein; DPC, diagnosis procedure combination; FAP, full analysis population; FeNO, fractional exhaled nitric oxide; GERD, gastroesophageal reflux disease; ICD-10, International Classification of Diseases, 10th revision; ICS, inhaled corticosteroid; IgE, immunoglobulin E; LABA, long-acting beta-agonist; LAMA, long-acting muscarinic antagonist; LTRA, LT receptor antagonist; OCS, oral corticosteroid; RAST, radioallergosorbent test; SABA, short-acting beta-agonist; SD, standard deviation.

Data Sharing Statement

Data underlying the findings described in this manuscript may be obtained in accordance with AstraZeneca’s data sharing policy described at https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.

Acknowledgments

This work was supported by AstraZeneca K.K., Osaka, Japan. The study sponsor was involved in designing the study, analyzing and interpreting the data, and writing the report. The authors would like to thank EP Corporation for data analyses, EMC K.K. for medical writing services, and Edanz, Japan, for providing editorial support, all of which were funded by AstraZeneca K.K. The authors would also like to thank Kaori Oneda for their contribution in conducting the study.

Author Contributions

All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.

Disclosure

SH has received honoraria from AstraZeneca, GlaxoSmithKline, Novartis Pharma, and Kyorin Pharmaceutical. KO, NM, HU, and YA are employees of AstraZeneca K.K. TH and NT are employees of and hold stock in AstraZeneca K.K. TH reports gain on sale of stocks (Daiichi Sankyo), outside the submitted work. The authors report no other conflicts of interest in this work.

Additional information

Funding

This research was funded by AstraZeneca K.K., Osaka, Japan.