Published Online: October 7, 2016
Asthma is relatively common in older patients, reported in 4% to 13% of persons older than 60 years, and this number will likely increase as people are living longer. This age group of patients has one of the highest rates of asthma morbidity and mortality. Despite these statistics, there is limited data regarding airway inflammation in aged adults with asthma and how it may affect asthma control. Previous studies on patients in this age group suggest that there are increased airway neutrophils, although they have not considered the impact of low grade basal systemic inflammation often observed in aging (“inflamm-aging”) and have not recruited inner-city patients, an at-risk asthma population in the United States.
In an article recently published in The Journal of Clinical Immunology (JACI), Busse and colleagues collected induced sputum in aged (>60 years) and younger (21-40 years) inner-city patients with asthma, a marker of asthma control (Asthma Control Test), and utilization of asthma resources (i.e., hospitalizations, prednisone bursts, etc.) in the past year. To control for the effect of aging on airway inflammation, they obtained induced sputum from age-matched patients without asthma.
The authors found that aged compared to younger asthma patients had significantly worse asthma control and a distinct pattern of sputum inflammation (increased neutrophils and eosinophils, and elevated protein expression of IL-1, IL-6, IL-8, eotaxin, GM-CSF and cytokines associated with Th17 cells). These differences in airway inflammation could not be explained by increased age itself. In aged patients with asthma, increased levels of many of these proteins and neutrophils were related to worse asthma control and increased asthma hospitalizations in the past year.
These findings suggest that aging and asthma affect airway inflammation and the differences in inflammation may explain decreased asthma control in the aged. Establishing the characteristics of airway inflammation in aged asthma patients is a step towards a greater understanding of the high morbidity and mortality rates in this population.
The Journal of Allergy and Clinical Immunology (JACI) is the official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.