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Prevalence, age at onset, and risk factors of self‐reported asthma among Swedish adolescent elite cross‐country skiers

The objective of the study was to compare the prevalence of self‐reported physician‐diagnosed asthma and age at asthma onset between Swedish adolescent elite skiers and a reference group and to assess risk factors associated with asthma. Postal questionnaires were sent to 253 pupils at the Swedish National Elite Sport Schools for cross‐country skiing, biathlon, and ski‐orienteering (“skiers”) and a random sample of 500 adolescents aged 16‐20, matched for sport school municipalities (“reference”). The response rate was 96% among the skiers and 48% in the reference group. The proportion of participants with self‐reported physician‐diagnosed asthma was higher among skiers than in the reference group (27 vs 19%, P=.046). Female skiers reported a higher prevalence of physician‐diagnosed asthma compared to male skiers (34 vs 20%, P=.021). The median age at asthma onset was higher among skiers (12.0 vs 8.0 years; P<.001). Female sex, family history of asthma, nasal allergy, and being a skier were risk factors associated with self‐reported physician‐diagnosed asthma. Swedish adolescent elite cross‐country skiers have a higher asthma prevalence and later age at asthma onset compared to a reference population. Being an adolescent, elite skier is an independent risk factor associated with asthma.