title: Phenotypes, Risk Factors, and Mechanisms of Adult-Onset Asthma.
abstract: Asthma is a heterogeneous disease with many phenotypes, and age at disease onset is an important factor in separating the phenotypes. Genetic factors, atopy, and early respiratory tract infections are well-recognized factors predisposing to childhood-onset asthma. Adult-onset asthma is more often associated with obesity, smoking, depression, or other life-style or environmental factors, even though genetic factors and respiratory tract infections may also play a role in adult-onset disease. Adult-onset asthma is characterized by absence of atopy and is often severe requiring treatment with high dose of inhaled and/or oral steroids. Variety of risk factors and nonatopic nature of adult-onset disease suggest that variety of mechanisms is involved in the disease pathogenesis and that these mechanisms differ from the pathobiology of childhood-onset asthma with prevailing Th2 airway inflammation. Recognition of the mechanisms and mediators that drive the adult-onset disease helps to develop novel strategies for the treatment. The aim of this review was to summarize the current knowledge on the pathogenesis of adult-onset asthma and to concentrate on the mechanisms and mediators involved in establishing adult-onset asthma in response to specific risk factors. We also discuss the involvement of these mechanisms in the currently recognized phenotypes of adult-onset asthma.
authors.affiliation: Department of Respiratory Medicine, Seinäjoki Central Hospital, 60220 Seinäjoki, Finland.
authors.forename: Pinja
authors.initials: P
authors.lastname: Ilmarinen
authors.affiliation: Department of Respiratory Medicine, Seinäjoki Central Hospital, 60220 Seinäjoki, Finland.
authors.forename: Leena E
authors.initials: LE
authors.lastname: Tuomisto
authors.affiliation: Department of Respiratory Medicine, Seinäjoki Central Hospital, 60220 Seinäjoki, Finland ; Department of Respiratory Medicine, University of Tampere, 33014 Tampere, Finland.
authors.forename: Hannu
authors.initials: H
authors.lastname: Kankaanranta
mesh_terms: D017668:Age of Onset; D000393:Air Pollutants; D000428:Alcohol Drinking; D000818:Animals; D001249:Asthma / Q000150:complications / Q000473:pathology*; D003863:Depression / Q000150:complications / Q000473:pathology; D004777:Environment; D005260:Female; D012739:Gonadal Steroid Hormones / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000473:pathology; D008019:Life Style; D008297:Male; D009765:Obesity / Q000150:complications; D016273:Occupational Exposure; D018384:Oxidative Stress; D010641:Phenotype; D012141:Respiratory Tract Infections / Q000150:complications / Q000473:pathology; D012220:Rhinitis / Q000150:complications; D012307:Risk Factors; D012737:Sex Factors; D012852:Sinusitis / Q000150:complications; D012907:Smoking
chemical_list: D000393:Air Pollutants; D012739:Gonadal Steroid Hormones