Prevalence of type 2 multimorbidities in COPD compared to asthma and relationship to blood eosinophilic counts.

Background: Type 2 (T2) inflammation is increasingly recognised in COPD, though its immunopathological profile may differ from asthma. T2 inflammatory diseases often coexist, but their prevalence in COPD patients without asthma remains underexplored. This study investigated the prevalence of T2 inflammatory multimorbidities in individuals with COPD (without asthma) and compared it with those in people with asthma. It also examined the relationship between these multimorbidities and blood eosinophil counts (BEC). Methods: Using data from the Optimum Patient Care Research Database (OPCRD), we identified patients with COPD or asthma and assessed lifetime and adjusted prevalence of T2 comorbidities including allergic rhinitis, atopic dermatitis/eczema, nasal polyps, chronic rhinitis with or without polyps, eosinophilic oesophagitis and ulcerative colitis. Prevalence was stratified by BEC and adjusted for demographic and clinical variables. Results: Among 122 509 COPD and 1 154 094 asthma patients, T2 multimorbidities were present in both groups but significantly less common in COPD. Allergic rhinitis and nasal polyps were notably less prevalent in COPD, even at higher BEC levels. Prevalence of multimorbidities increased with BEC in both groups, with stronger associations observed for nasal polyps and ulcerative colitis. Eosinophilic oesophagitis was rare across both cohorts. Conclusion: T2 multimorbidities are present in COPD and their prevalence increases with BEC, though they are generally less prevalent than in asthma, suggesting distinct immunopathology.