Asthma-OSA overlap syndrome: A distinct endophenotype?

Area of Science:

• Respiratory Medicine
• Sleep Medicine
• Immunology

Background:

• Asthma and obstructive sleep apnea (OSA) frequently coexist, forming alternative overlap syndrome (aOVS).
• This condition is often underestimated and underdiagnosed, despite shared risk factors like obesity, GERD, and rhinitis.
• aOVS presents unique pathophysiological characteristics, including low arousal threshold, nocturnal bronchial hyperresponsiveness, and autonomic dysfunction.

Purpose of the Study:

• To review current evidence on aOVS, covering its pathophysiology, clinical, functional, and therapeutic aspects.
• To evaluate if aOVS represents a distinct endophenotype requiring tailored diagnostic and therapeutic approaches.
• To highlight the importance of recognizing aOVS for improved patient outcomes.

Main Methods:

• Comprehensive literature review of studies on asthma and OSA overlap.
• Analysis of pathophysiological mechanisms linking asthma and OSA.
• Evaluation of clinical, functional, and therapeutic data from patients with aOVS.

Main Results:

• aOVS patients exhibit reduced FEV1 and increased nocturnal hypoxemia compared to those with single conditions.
• The syndrome is associated with poorer asthma control, more frequent exacerbations, and diminished quality of life.
• Continuous positive airway pressure (CPAP) therapy improves asthma control, symptom burden, and inflammation.

Conclusions:

• aOVS should be recognized as a distinct clinical endophenotype.
• Timely identification and personalized management strategies are essential for improving patient care.
• Further research is needed to understand long-term outcomes and optimize personalized therapies for aOVS.