Effect of a concomitant diagnosis of allergic rhinitis on asthma-related health care use by adults

Abstract

Background: Asthma and allergic rhinitis (AR) frequently coexist, but have usually been studied separately in health economic analyses.

Objective: To determine the incremental effect of documented AR on health care resource use in adults with asthma.

Methods: A retrospective cohort study using data from a UK general practice database for the period 1998-2001 enrolled subjects 16-55 years of age, with one or more asthma-related general practitioner (GP) visits during a 12-month follow-up period. The study outcomes were asthma-related hospitalizations, GP visits, and prescription drug costs during the 12-month follow-up period for patients with and without physician-diagnosed AR.

Results: Concomitant AR was documented in 4,611 (16.9%) of the total sample of 27,303 adults with asthma. Compared with those with asthma alone, patients with concomitant AR experienced more GP visits (5.2 vs. 4.2; P<0.0001) and more of them were hospitalized for asthma (0.76% vs. 0.45%; P<0.01) during the 12-month follow-up period. In multi-variable regression analyses, AR was predictive of hospitalization for asthma (odds ratio 1.52, 95% confidence interval (CI) 1.03-2.24) and was associated with an increase in the annual number of asthma-related GP visits (mean increase per patient 0.42, 95% CI 0.42-0.43) and annual asthma-related drug costs (mean increase GBP 5.1, 95% CI 5.0-5.3).

Conclusion: Adults with asthma and documented concomitant AR experienced more asthma-related hospitalizations and GP visits, and incurred higher asthma drug costs than did adults with asthma alone. A unified treatment strategy for asthma and AR might reduce the costs of treating these conditions.