This Israeli study followed up 180 mild to moderate asthmatics (mean age 23.9 years, 50% female) who were travelling to developing countries for, on average, 4 months. History, examination and spirometric tests were performed before and after exercise.

Asthma attacks during travel were reported by 88 subjects; 32 had their worst ever attack and 11 had life threatening exacerbations. Frequent (≥3/week) use of bronchodilators before travel (RR 3.35, p<0.001), emergency department treatment in the previous year, pre-exercise wheezing, and significant wheezing after exercise were all identified as risk factors for worsening of asthma. Intensive trekking was also a risk factor (RR 2.04, p=0.04). It was noted that most subjects failed to foresee the possibility of worsening of their asthma during travel and there was significant underuse of inhaled corticosteroids in all groups.

Further studies are needed to assess the usefulness of optimising asthma control before travel, avoidance of intensive trekking, and the use of crisis management plans to minimise the frequency of asthma attacks in adventure travellers.