Adjusted incidence, remission, and relapse of self-reported physician-diagnosed asthma and asthma medication usage in endurance athletes.

ABSTRACT

Longitudinal studies are needed to increase our knowledge of the natural history of asthma in athletes. Our aims were to estimate the incidence, remission, and relapse, of self-reported asthma among endurance athletes. A postal questionnaire on self-reported physician-diagnosed asthma, asthma medication, allergy, and respiratory symptoms was sent annually 2011-2015 to 666 Swedish elite athletes competing in cross-country skiing, biathlon, ski orienteering, or orienteering. Athletes at risk for (1) incident asthma were those without previous self-reported asthma, use of asthma medication, or asthma-like symptoms, (2) remission those who discontinued asthma medication usage and (3) relapse those who resumed asthma medication usage during the observation period. The population at risk was used as denominator in the calculations of subsequent event rate. At baseline, 89% responded, the median age was 17 years and 47% were females. Of the 373 athletes with never asthma nor use of asthma medication/asthma-like symptoms at baseline, 31 (8%) reported physician-diagnosed asthma during follow-up, giving an adjusted incidence rate of asthma of 42/1000 person years. Among the 110 athletes with self-reported asthma and use of asthma medication at baseline, 26 (24%) discontinued use of asthma medication during the follow-up, giving a remission rate of 142/1000 person years. Of the 31 athletes with previous asthma and no use of asthma medication at baseline, 9 (29%) resumed use of asthma medication during follow-up, giving a relapse rate was 148/1000 person years. Elite endurance athletes have a high incidence of self-reported physician-diagnosed asthma. The remission and relapse of self-reported asthma medication usage in endurance athletes appear similar to that of the general population.