Early onset vs late onset asthma: two different diseases?
Published: August 11, 2022
Bronchial asthma is a heterogeneous disease, which can occur at any age. Patients with early-onset and late-onset asthma may exhibit phenotypic differences and may thus require a distinctive diagnostic and therapeutic approach. The impact of different comorbidities in symptoms control according to age of onset and disease characteristics remains poorly understood.
Turrin et al. in a recent Journal of Allergy and Clinical Immunology: In Practice article present the results of a study recruiting 175 adult patients attending a tertiary asthma clinic. Subjects were stratified according to age of symptom onset: early onset asthma (EOA, onset of symptoms <12 years) and late onset asthma (LOA, >40 years). The main comorbidities evaluated were rhinitis, gastroesophageal reflux, obesity, cardiovascular conditions, and bronchiectasis and the primary outcome was symptom control. The secondary outcomes were to explore reported comorbidities that were associated with lung function (FEV1, FEV1/FVC, FVC, FEF25-75) and inflammatory markers (total serum IgE, blood eosinophils and neutrophils).
Out of 175 subjects, 77 (44%) had EOA and 98 (56%) had LOA. EOA and LOA presented with distinct patterns of comorbidities which did have a differential impact on disease control. Rhinitis was more frequent in EOA than in LOA (76 vs 53%) and was associated with uncontrolled asthma, increased markers of allergic inflammation (eosinophils and total IgE) and reduced pulmonary function (FEV1/FVC). Conversely, in late onset asthma, rhinitis was not linked to poor asthma control or lung function abnormalities, but paradoxically, it was associated with better asthma control and preserved lung function. Obesity was present in 20% of patients in both early and late onset groups, but only in LOA was obesity associated with uncontrolled disease, reduced FEV1/FVC, and increased inflammation (neutrophils). Rhinitis in EOA and obesity in LOA were the risk factors most closely associated with poor control. Other comorbidities (gastroesophageal reflux, cardiovascular, and bronchiectasis) did not impact on symptoms control.
The study by Turrin et al focused on a real-life cohort of symptomatic asthmatic patients in their adulthood. Asthmatic patients with childhood onset are mainly characterized by rhinitis and allergic inflammation, which are closely related to symptoms and poor disease control. On the other hand, in asthmatic patients with onset in adulthood, a worse course of the disease is mainly related to being overweight and to a different (neutrophilic) inflammatory pattern. Close attention to the individual patient history, the pattern of inflammation, and the presence comorbidities is crucial to improve asthma symptom 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.