Published online: November 23, 2017
Asthma in the elderly population is often underdiagnosed and, due to its clinical heterogeneity, it can be confused with chronic obstructive pulmonary disease (COPD) or congestive heart failure. In many other cases, these diseases present as asthma-associated comorbidities. Asthma may be classified according to the age at onset of symptoms, and almost 50% of elderly asthmatic patients have asthma onset before the age of 40. Reports of allergic sensitization in elderly asthmatic patients vary widely (30%-75%), and atopy, although more prevalent in younger patients, can be a major cause of asthma in these patients.
In a study recently published in The Journal of Allergy and Clinical Immunology: In Practice, Agondi et al investigated the prevalence of the allergic phenotype in elderly asthmatic patients according to the age at symptoms onset. Comorbidities such as COPD, gastroesophageal reflux disease (GERD), obesity and aspirin exacerbated respiratory disease (AERD) were assessed in those patients.
The authors studied 243 elderly asthmatic patients enrolled in the Asthma Outpatient Clinic of the Clinical Immunology and Allergy Division, University of São Paulo, Brazil. They found that almost 75% of these patients had asthma requiring step 4 or 5 therapy and that spirometry (forced expiratory volume in the first second - FEV1) was abnormal in more than 80% of them. The authors also observed a high prevalence of atopy (63% of patients), mainly in the group of elderly patients whose asthma started before 12 years of age. There was also a high prevalence of GERD and obesity in both allergic and non-allergic asthmatic patients, but AERD was more prevalent in the nonallergic group. Although COPD is a complex diagnosis in elderly asthmatic patients, especially in those with late-onset disease, it was confirmed in 13% of study patients, independent of the atopic status. Forty percent of the elderly asthmatic patients had asthma before 20 years of age, resulting in long-standing disease, which was associated with a low FEV1 and a high prevalence of atopy.
The study findings showed that allergic sensitization is prevalent in elderly asthmatic patients and that it may be an important cause for long-standing asthma, leading to more severe disease. Other comorbidities were prevalent as well in both asthma phenotypes, allergic and nonallergic. Diagnosing allergic asthma in the elderly population is important in order to offer additional specific therapy for disease control.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.