Comorbidities associated with adult asthma according to severity: analysis of data from the National Health Insurance Sharing Service.

Background: Asthma is a heterogenous disease having varied phenotypes. The comorbidities associated with asthma vary with age and disease severity. The well-known asthma related comorbid conditions include rhinitis, gastroesophageal reflux disease (GERD), hypertension, obstructive sleep apnea, hormonal disorders, and psychiatric disorders. However, comprehensive analyses of how asthma severity correlates with the prevalence and type of comorbidities remain limited. Understanding these relationships is essential for developing targeted management strategies. This study aims to analyze the comorbid conditions associated with adult asthma based on severity, using data from the National Health Insurance Sharing Service. By comparing non-severe asthma (NSA) and severe asthma (SA) groups, the study seeks to identify key differences in the prevalence and risks of comorbid diseases, thereby providing valuable insights for clinicians managing asthma patients. Methods: National Health Insurance claim records from July 1, 2014 to June 31, 2016 were analyzed in a retrospective population-based study. We analyzed the frequent comorbidities in adult patients with asthma. Patients were divided into the following groups according to severity of asthma: NSA and SA. Risk of the developing major comorbid diseases conditions were analyzed according to the morbidity and severity of asthma. Results: Vasomotor and allergic rhinitis, bronchitis, upper respiratory infection, and GERD were common comorbid conditions in all patients with asthma. chronic obstructive pulmonary disease was more common in SA than in NSA. In major comorbid diseases, patients with asthma had more risk in chronic diseases such as diabetes mellitus [odds ratio (OR) =1.13; 95% confidence interval (CI): 1.13, 1,14] and various types of psychiatric disorder (OR =1.49; 95% CI: 1.48, 1.49), as well as rhinitis (OR =1.94; 95% CI: 1.94, 1.95), GERD (OR =1.66; 95% CI: 1.66, 1.67), and osteoporosis (OR =1.40; 95% CI: 1.39, 1.41). Patients with SA experienced more comorbidities and higher incidence of cardiovascular disease, cerebrovascular disease, dementia, and several psychiatric disorders than patients with NSA. Conclusions: Patients with asthma had a higher risk of chronic diseases than patients without asthma, and there was a tendency of higher risk of major comorbidities in SA. Clinicians should consider the impact of comorbid diseases in the asthma patient care.