Primary care referral patterns for patients with asthma: analysis of real-world data

To identify features related to management of patients prior to referral from primary care physicians (PCPs) to pulmonologists and allergists.

This is an analysis of patient claims data from Symphony Health (2013-2018). To characterize referrals, a longitudinal cohort included 12 months with no asthma claims prior to the index date, followed by 36 months of observation. We also assessed a cross-sectional cohort for 12 months at the end of the observational period to characterize disease control and treatment patterns. Referral was defined as the first appearance of a claim from an allergist or pulmonologist for a patient's initial visit for asthma. Descriptive statistics were used to analyze the data.

The majority of patients with asthma were managed by PCPs (60%), followed by pulmonologists (16%) and allergists (8%). Forty-three percent had uncontrolled asthma. Only 8% were referred to specialists within the first 24 months after initial diagnosis, of which 76% were seen by pulmonologists and 24% by allergists. Referrals resulted in treatment change in 55%-68% of the cases. Patients who received a referral were more likely to be on oral corticosteroids (OCS) and/or have more hospitalizations/ED visits.

About one-third of the patients managed by PCPs received intermittent and/or chronic OCS prior to referral, which may be an indication of uncontrolled disease. The referral patterns in this analysis illustrate underutilization of specialists in the consultation and management of patients with uncontrolled asthma.