Systemic Inflammation in Older Adults With Asthma-COPD Overlap Syndrome

Abstract

PurposeThe role of systemic inflammation on asthma-COPD overlap syndrome is unknown. This study aimed to examine systemic inflammation in asthma-COPD overlap syndrome, and to identify associations between clinical characteristics and inflammatory mediators in asthma-COPD overlap syndrome.MethodsIn 108 adults older than 55 years comprising healthy controls (n=29), asthma (n=16), COPD (n=21) and asthma-COPD overlap syndrome (n=42), serum high sensitivity C-reactive protein and Interleukin 6 (IL-6) were assayed. Spirometry, induced sputum, quality of life, comorbidities and medications were assessed, and their associations with asthma-COPD overlap syndrome were analyzed using logistic regression. Associations between systemic inflammatory mediators and clinical characteristics were tested in multivariate linear regression models.ResultsPatients with asthma-COPD overlap syndrome had significantly elevated IL-6 levels compared with healthy controls and asthmatics. Age, comorbidity index and IL-6 level were independently associated with asthma-COPD overlap syndrome. FEV1% predicted was inversely associated with IL-6 level, and cardiovascular disease was associated with an increased IL-6 level. Systemic markers were not associated with airway inflammation.ConclusionsSystemic inflammation is commonly present in asthma-COPD overlap syndrome, and asthma-COPD overlap syndrome resembled COPD in terms of systemic inflammation. IL-6 is a pivotal inflammatory mediator that may be involved in airflow obstruction and cardiovascular disease and may be an independent treatment target.

Asthma and chronic obstructive pulmonary disease overlap: asthmatic chronic obstructive pulmonary disease or chronic obstructive asthma?

“…Also, IL-6 levels were higher in patients with cardiovascular disease compared with patients without the disease, suggesting that systemic inflammation leads to comorbid disease. Interestingly, in a univariate logistic regression analysis, FEV 1 % predicted, sputum neutrophil counts, CCI and IL-6 predicted the risk of having ACOS (not sputum eosinophils) [Fu et al 2014]. In contrast, in the EPISCAN study several blood biomarkers were evaluated, namely albumin, α1 antitrypsin, fibrinogen, C-reactive protein, tumour necrosis factor (TNF)-α, IL-6, IL-8 and nitrite/nitrate (NOx).…”

“…Also, these markers of systemic inflammation are associated with age, smoking [Pinto-Plata et al 2006], comorbid disease, such as cardiovascular disease [Danesh et al 2004], obesity and diabetes [Bastard et al 2006]. High levels of IL-6 are inversely related to FEV 1 [Fu et al 2014;Walter et al 2008], a faster decline in FEV 1 [Thorleifsson et al 2009] and with an increased risk of developing COPD [Yanbaeva et al 2009]. …”

Application of impulse oscillometry and bronchial dilation test for analysis in patients with asthma and chronic obstructive pulmonary disease

“…Generally, reversibility of airflow limitation is incomplete in COPD, while that in asthma can be complete [18]. Therefore, asthma and COPD may overlap and converge [19,20]. Our study was to explore the application and clinical value of combining IOS and BDT for differential diagnosis between asthma and COPD.…”

Asthma COPD overlap syndrome (ACOS)

“…Study revealed that CRP and IL-6 levels in ACOS patients were higher than asthma patients and similar to COPD patients suggesting that ongoing systemic inflammation in ACOS patients is as worse as COPD patients [29].…”