Allergic Rhinitis and Changing Nasal Congestion after Continuous Positive Airwary Pressure

Abstract

Objective: Among continuous positive airway pressure (CPAP) users, self-reported allergic rhinitis has been associated with relative worsening of subjective nasal congestion. This study’s aims were to test the associations between objective allergic rhinitis status and 1) change in objective nasal congestion after CPAP initiation, or 2) objective CPAP use.

Method: Objective allergic rhinitis status was established by skin-prick test of 17 region-specific aeroallergens in CPAP patients with baseline turbinate hypertrophy. Objective nasal congestion was measured by acoustic rhinometry (combined bilateral minimal cross-sectional area, MCA) at baseline and 3-months later in subjects using CPAP. Objective CPAP use was measured at 12 months.

Results: This cohort study included n = 81 subjects from a larger parent trial on turbinate hypertrophy in CPAP patients. In this cohort, MCA did not change significantly in subjects with allergic rhinitis (n = 51, paired t-test P = .18) or in controls (n = 30, paired t-test P = .67) after initiation of CPAP, and there was no significant difference in change between groups (t-test P = .28). CPAP use in allergic rhinitis subjects (1.9 ± 2.7 h/night) was not significantly different from controls (2.4 ± 3.0 h/night; Mann-Whitney U test, P = .28), but statistical power was limited for the observed difference (power 12%).

Conclusion: Allergic rhinitis did not predict worsening of objective nasal congestion with CPAP initiation or decreased CPAP use, but confounding, eligibility criteria, limits of objective nasal measurements, and insufficient statistical power may have blunted a true effect. Further studies are needed.