Age-specific incidence of allergic and non-allergic asthma

• Published in: BMC pulmonary medicine Vol. 20; no. 1; p. 9
• Main Authors: Pakkasela, Johanna, Ilmarinen, Pinja, Honkamäki, Jasmin, Tuomisto, Leena E., Andersén, Heidi, Piirilä, Päivi, Hisinger-Mölkänen, Hanna, Sovijärvi, Anssi, Backman, Helena, Lundbäck, Bo, Rönmark, Eva, Kankaanranta, Hannu, Lehtimäki, Lauri
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 10.01.2020; BioMed Central; BMC
• Subjects: Adolescent; Adult; adult-onset asthma; Adults; Age groups; Age-specific; Allergic; Allergic rhinitis; Allergies; Allergy; Asthma; Atopy; Child; Childhood; Childhood asthma; Children; Cluster analysis; common allergens; Development and progression; Diagnosis; Disease age factors; Epidemiology; helsinki; Hypersensitivity; Immunologi inom det medicinska området; Immunology in the Medical Area; Incidence; Lungmedicin och allergi; Non-allergic; Onset; phenotypes; Physicians; Population; Prevalence; Pulmonology; reported asthma; Respiratory Medicine and Allergy; Respiratory System; Rhinitis; risk-factors; sensitization; Studies; Surveys; Womens health; Young adults; Finland; Sweden; Non-allergic; Prevalence; Adolescent; Adult; Child; Age-specific; Allergic; Asthma; Incidence; Onset
• ISSN: 1471-2466; 1471-2466
• DOI: 10.1186/s12890-019-1040-2

Onset of allergic asthma has a strong association with childhood but only a few studies have analyzed incidence of asthma from childhood to late adulthood in relation to allergy. The purpose of the study was to assess age-specific incidence of allergic and non-allergic asthma. Questionnaires were sent to 8000 randomly selected recipients aged 20-69 years in Finland in 2016. The response rate was 52.3% (n = 4173). The questionnaire included questions on e.g. atopic status, asthma and age at asthma diagnosis. Asthma was classified allergic if also a physician-diagnosed allergic rhinitis was reported. The prevalence of physician-diagnosed asthma and allergic rhinitis were 11.2 and 17.8%, respectively. Of the 445 responders with physician-diagnosed asthma, 52% were classified as allergic and 48% as non-allergic. Median ages at diagnosis of allergic and non-allergic asthma were 19 and 35 years, respectively. Among subjects with asthma diagnosis at ages 0-9, 10-19, 20-29, 30-39, 40-49, 50-59 and 60-69 years, 70, 62, 58, 53, 38, 19 and 33%, respectively, were allergic. For non-allergic asthma, the incidence rate was lowest in children and young adults (0.7/1000/year). It increased after middle age and was highest in older age groups (2.4/1000/year in 50-59 years old). The incidence of allergic asthma is highest in early childhood and steadily decreases with advancing age, while the incidence of non-allergic asthma is low until it peaks in late adulthood. After approximately 40 years of age, most of the new cases of asthma are non-allergic.