High prevalence of contact allergy in adolescence: results from the population-based BAMSE birth cohort

BackgroundContact allergy is common among adults. However, little is known about the prevalence in adolescents. ObjectivesTo assess the prevalence of allergy to common contact allergens in Swedish adolescents in the general population. Participants and methodsThe BAMSE cohort is a population-based birth cohort with the main aim of studying the risk factors for asthma, rhinitis, and atopic dermatitis. Patch testing was performed at the 16-year follow-up. The test (TRUE Test((R))) was applied at home, and removed 2 days later by nurses, who recorded and photographed the results. Dermatologists made final assessments on the basis of photographs and protocols. ResultsTwo thousand two hundred and eighty-five participants (88% of all 16-year follow-up participants) were patch tested; 15.3% had at least one positive reaction. Contact allergy was more common in girls than in boys (17.0% versus 13.4%, p = 0.018). Sensitization to nickel was most common (7.5%), followed by sensitization to fragrance mix I (2.1%) and p-tert-butylphenol formaldehyde resin (1.9%). Nickel allergy was more frequent in girls (9.8% versus 4.9%, p < 0.001). Solitary sensitization to cobalt was more common than co-sensitization to nickel and cobalt. ConclusionsThe prevalence of contact allergy in adolescents is of almost the same high magnitude as in adults. The applied method was feasible in the population-based setting.