Persistent asthma from childhood to adulthood presents a distinct phenotype of adult asthma

Abstract Background In approximately 30% of children with asthma, the condition persists into adulthood. The longer duration of asthma in these patients is a risk factor for poor asthma control. However, the characteristics of adult patients with asthma that has persisted since childhood are not well documented. Objective We sought to compare the clinical characteristics among patients with adult-onset asthma, patients who outgrew childhood asthma but relapsed, and patients with persistent asthma since childhood. Methods We conducted a cross-sectional study of adult patients with asthma who visited our hospital. We classified them into three groups: those with adult-onset asthma (adult-onset), those who had remitted childhood asthma which relapsed (relapsed), and those who had asthma that had persisted since childhood (persistent). The clinical characteristics of these groups were compared. Results A total of 1443 patients were enrolled. The persistent group was younger and included fewer patients with a smoking history. There were statistically significant differences among the three groups in the percentages of patients with a family history of asthma and comorbidities of allergic rhinitis and atopic dermatitis. The proportion of patients with severe asthma differed among the three groups (31% in the adult-onset group, 34% in the relapsed group, and 40% in the persistent group; p=0.015). The values of FEF75 were lower in the persistent group than the relapsed or adult-onset group. A multivariable logistic regression analysis (dependent variable: severe asthma) in each group revealed that the factors associated with severe asthma differed among the adult-onset, relapsed, and persistent groups. When we established an overall model that included interaction terms of cohort-by-other factors, there was a trend that comorbidity of allergic rhinitis affected the severity of asthma differently in the relapsed group compared to the other groups. Conclusions The clinical phenotype of asthma that persists from childhood to adulthood seems to be a distinct phenotype of adult asthma.