Background: It is well known that cold, altitude and exercise during mountain activities can impair the human immune system. Moreover, a transient decrease in plasma immunoglobulins (Ig) levels during the acute phase of adults' community-acquired pneumonia (CAP) has been observed. The authors intend to verify these statements in a group of mountain athletes. Objective: Our main objective was to confirm that serum Ig levels decrease after sustained exercise in a cold environment at high altitude. The secondary objective is to study their role in winter sportsperson's respiratory tract infections. Methods: A prospective observational study was done, enrolling participants of a mushing race: contestants (cases, divided into mushers/skijörers and handlers) and organization staff (controls). Demographical data and a blood sample were collected at the beginning and a second blood sample during the second week of the competition. Ig levels in each sample levels were determined and comparisons were done with non parametric tests: Kruskal Wallis, Wilcoxon signed-rank, Mann-Whitney U. Results: Information from 31 individuals and plasma Ig levels from 47 was available for analysis, studying 14 cases and 33 controls. IgA and IgM levels were decreased in the first sample when participants in the race and supporting staff were compared (176 vs 245 mg/dL, p=0.02; and 94 vs 125 mg/dL, p=0.045), irrespective of age, gender, previous physical activity or place of residence. In the second sample no significant differences in any Ig class were disclosed, even after stratification by groups (case/control) or previous training level. Conclusions: IgA levels tend to be decreased in people who exercise at high altitude, but further studies with a greater number of participants are needed to better define the relationship between exercise, environmental variables, immunological deficit, and the development of infections. Influence of low levels of Ig on respiratory tract infections could not be verified. This information could help in the development of recommendations to people practicing sports at high altitude, in order to minimize the risk of infection.
|Journal||Archivos de Medicina del Deporte|
|Publication status||Published - 1 Jan 2014|
- Respiratory tract infections
- Snow sports
- Track and field