Update on Asthma-COPD Overlap (ACO): A Narrative Review.

Area of Science:

• Pulmonology
• Respiratory Medicine
• Clinical Medicine

Background:

• Asthma and Chronic Obstructive Pulmonary Disease (COPD) are distinct respiratory conditions.
• Asthma-COPD Overlap (ACO) describes patients exhibiting characteristics of both asthma and COPD.
• ACO may affect approximately 25% of COPD patients and 20% of asthma patients.

Purpose of the Study:

• To review the current understanding of Asthma-COPD Overlap (ACO).
• To discuss ACO definitions, prevalence, clinical features, and management.
• To explore emerging aspects like genetics, epigenetics, and biomarkers in ACO.

Main Methods:

• Literature review of current research on Asthma-COPD Overlap.
• Analysis of definitions, diagnostic criteria, and epidemiological data.
• Synthesis of information on clinical manifestations, treatment implications, and guideline positioning.

Main Results:

• ACO is characterized by non-reversible airflow limitation, significant exposure to noxious agents, and asthma-like features.
• Accurate ACO identification influences therapeutic strategies, including inhaled corticosteroid use.
• Emerging research is exploring genetic, epigenetic, and biomarker profiles in ACO.

Conclusions:

• Standardized definitions and guideline integration for ACO are still evolving.
• Recognizing ACO is vital for optimizing treatment and improving patient outcomes.
• Further research into ACO's underlying mechanisms and personalized treatments is warranted.