New Asthma Diagnosis Codes or Short-Acting β2 Agonist Prescriptions After Histoplasmosis Among Patients With Commercial Health Insurance, United States, 2018-2023.

Background: Although several fungal infections have been linked to asthma development, the relationship between histoplasmosis and asthma development has not been fully described.

Objectives: To assess the incidence of new asthma diagnosis codes or short-acting β₂ agonist (SABA) prescription in the year following histoplasmosis diagnosis and identify potentially related factors.

Methods: We used a large health insurance claims database to identify patients with histoplasmosis with and without an asthma diagnosis code or a short-acting β₂ agonist prescription in the year after diagnosis.

Results: Among 1819 patients diagnosed with histoplasmosis, 252 (13.9%) received a new asthma diagnosis or SABA prescription in the subsequent year, more than double the proportion in the general population (5.8%). Pulmonary histoplasmosis and symptoms such as dyspnea and wheezing were associated with asthma diagnosis or SABA receipt.

Conclusion: These findings suggest that histoplasmosis may predispose certain patients to airway hyperreactivity, particularly those with acute pulmonary symptoms. Further research is needed to elucidate potential mechanisms underlying these findings, which could inform strategies to mitigate post-infectious airway disease in affected patients.