Asthma - COPD Overlap Syndrome

(ACOS)

Yung-Yang Liu, MD Chest Department

Taipei Veterans General Hospital Nov. 7, 2015

Definition

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Bronchial Hyperresponsiveness (BHR)

• In asthma, there is good evidence that the degree of BHR is related to eosinophilic inflammation, and ICS may normalize BHR.

• The prevalence of BHR among patients with COPD has been reported to be 60%1.

• The decline of FEV1 is accelerated in COPD patients with BHR and the decline more prominent in smokers.

• BHR is a marker for more severe disease in both asthma and COPD.

1. Tashkin DP, et al. Am Rev Respir Dis 1992; 145: 301-10.

Reversibility of Airway Obstruction

• The reversibility can diminish or disappear with long-standing asthma.

• Reversibility is frequently present in COPD and was observed in up to 44%1 and 50%2 in two studies.

• Reversibility occurs in larger airways of patients with COPD but in a more wide-spread fashion in patients with asthma.

1. Bleecker ER, et al. Pulm Pharmacol Ther 2008; 21: 682-8. 2. Tashkin DP, et al. N Engl J Med 2008; 359: 1543-51.

Atopy in Asthma and COPD

• Two studies have investigated cohorts of patients with COPD for the presence of atopy and have shown prevalences of 18%1 and 30%2.

• Male and high BMI were associated with blood eosinophilia, a marker of atopy, in the ECLIPSE3 study in patients with mild-to-severe COPD.

• Patients with COPD who have atopy may benefit most from ICS treatment.

1. Fattahi F, et al. Respir Res 2013; 14: 10. 2. Jamieson DB, et al. Am J Respir Crit Care Med 2013; 188: 187-92. 3. Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE) study.

Airway Inflammation in Asthma and COPD

• Patients with asthma who have severe or late-onset disease or chronic infections or smoke may exhibit neutrophilic inflammation and CD8 in airways.

• Eosinophils in sputum, BAL, lung tissue are present in 15% to 40% of patients with stable COPD1.

• Eosinophils can also be increased in the sputum of patients with COPD exacerbation.

• Eosinophilic inflammation in blood, sputum, lung tissue signifies an endotype of COPD.

1. Barker BL, et al. Clin Sci (Lond) 2013; 124: 371-87.

Thanks for your attention !