Degree and clinical relevance of sensitization to common allergens among adults: a population study in Helsinki, Finland

Abstract

Background: We aimed to assess the prevalence of allergic sensitization and multiple sensitization, risk factors, and the clinical impact of being sensitized in the adult population of Helsinki, Finland.

Methods: As a part of the FinEsS study, a population-based random sample of 498 adults aged 26-60 years were tested for 15 common aeroallergens with skin prick tests (SPTs) and interviewed on respiratory symptoms and diseases, including respiratory irritants and childhood environment.

Results: The prevalence of at least one positive prick test was 46.9%. A large difference by age was found: 56.8% were sensitized among those aged 26-39 years, 49.2% in the age group 40-49 years, and 35.6% in the age group 50-60 years (P<0.001). Sensitization to multiple allergens was common among young subjects with 42% of the sensitized responding to at least four allergens, while this proportion was only 16% of the sensitized among those aged 50-60 years. The prevalence of physician-diagnosed asthma, allergic rhinitis (AR) or conjunctivitis, and wheeze increased significantly with increasing number of positive responses to SPTs. Having a family history of AR or conjunctivitis was a significant risk factor for allergic sensitization and for sensitization to any of the pollens. Further, urban living in childhood yielded an increased risk for pollen sensitization.

Conclusions: The prevalence of allergic sensitization was high in the urban adult population of Helsinki. More than half of those aged 26-39 years was sensitized and 24% was sensitized to at least four allergens. Sensitization to multiple allergens was associated with a high prevalence of asthma, AR or conjunctivitis, and wheeze.