[Mapping comorbidities in bronchial asthma: A disaggregated analysis of exacerbations, SABA and SAMA use in the...

Comorbidities are key determinants of asthma instability, exacerbating symptoms and increasing rescue medication use; however, their differential impact on specific clinical markers remains insufficiently defined. This study evaluated the association between individual comorbidities and 4distinct indicators of clinical instability: (1) exacerbations (2) isolated use of short-acting β₂-agonists (SABA), (3) isolated use of short-acting muscarinic antagonists (SAMA), and (4) combined use of rescue medication (SABA and/or SAMA).

A retrospective observational study was conducted with 132 adult asthma patients attended in primary care settings in Seville and Valencia (Spain). Clinical and pharmacological data were extracted from electronic health records. Associations between comorbidities and instability indicators were analyzed using the χ² test or Fisher's exact test.

SABA use was associated with allergic rhinitis, anxiety/depression, and sleep apnea, whereas SAMA use was linked to hypertension, chronic kidney disease, and multimorbidity. Only SAMA use was significantly associated with increased risk of exacerbations (OR=5.97; 95%CI: 2.43-14.66; P<.001). Combined use of rescue medication identified a complex phenotype with a substantial comorbid burden including allergic, cardiovascular, and psychosocial conditions.

This study demonstrates, for the first time, that comorbidities define specific clinical phenotypes in asthma, highlighting SAMA use as a key indicator of exacerbations and multimorbidity. Systematic identification of these profiles would enable more precise risk stratification and personalized therapies, extending asthma management beyond airway-centered approaches.