Comorbidity profiles in adults with different rhinitis phenotypes: a comparative analysis

BACKGROUND: The comorbidity profile of local allergic rhinitis remains insufficiently studied, and data from direct comparisons of local allergic rhinitis with allergic rhinitis and non-allergic rhinitis within a single cohort are limited.

AIM: To compare the patterns and prevalence of comorbid conditions in adult patients with allergic rhinitis, local allergic rhinitis, and non-allergic rhinitis.

METHODS: A single-center retrospective secondary analysis was performed using data from a cohort of adults with chronic rhinitis assembled in 2023–2024 based on clinical and allergy evaluation. Allergic rhinitis was diagnosed when immunoglobulin E mediated sensitization to clinically relevant aeroallergens was identified. In the absence of such sensitization, local allergic rhinitis and non-allergic rhinitis were differentiated based on positive and negative nasal allergen challenge results, respectively. Data from 2,078 patients were analyzed, including 1,989 with allergic rhinitis, 14 with local allergic rhinitis, and 75 with non-allergic rhinitis. The frequencies of comorbid conditions were compared, and the association between the number of type 2 inflammation–associated conditions and membership in the local allergic rhinitis group versus the non-allergic rhinitis group was assessed with adjustment for age.

RESULTS: Compared with non-allergic rhinitis, allergic rhinitis was more frequently associated with bronchial asthma (35.9 % vs 12.0 %; odds ratio 3.92; adjusted p < 0.001), conjunctivitis (50.4 % vs 29.3 %; odds ratio 2.42; adjusted p = 0.001), and food allergy (12.8 % vs 0 %; adjusted p < 0.001). Atopic dermatitis was more frequent in local allergic rhinitis than in non-allergic rhinitis (35.7 % vs 6.7 %; odds ratio 7.78; adjusted p = 0.023). Compared with allergic rhinitis, non-allergic rhinitis was more frequently associated with chronic bronchitis (odds ratio 3.76; adjusted p < 0.001), chronic obstructive pulmonary disease (odds ratio 10.21; adjusted p < 0.001), and gastroesophageal reflux disease (odds ratio 2.66; adjusted p = 0.002). In the age-adjusted model, a higher number of conditions associated with type 2 inflammation was associated with belonging to the local allergic rhinitis group rather than the non-allergic rhinitis group (odds ratio 23.0; 95 % confidence interval 4.5–118.5; p < 0.001).

CONCLUSION: Comorbidity profiles differed among allergic rhinitis, local allergic rhinitis, and non-allergic rhinitis. Allergic rhinitis was more frequently associated with bronchial asthma, conjunctivitis, and food allergy; local allergic rhinitis with atopic dermatitis; and non-allergic rhinitis with chronic bronchitis, chronic obstructive pulmonary disease, and gastroesophageal reflux disease. Comorbidity profiles may complement clinical phenotype assessment but cannot serve as an independent basis for diagnosing a rhinitis phenotype. Findings concerning local allergic rhinitis require confirmation in larger samples.