There have been no large-scale studies linking the reported high frequency of asthma and allergy disorders among athletes to comorbidities and immunological alterations associated with severe chronic exercise. This 12-year study seeks to investigate the characteristics, trends, and burden of asthma, allergies, infections, and autoimmune disorders in a large homogenous sample of Olympic athletes by evaluating numerous clinical, functional, and immunological parameters. Six hundred and fifty-nine Italian Olympic athletes were investigated between 2000 and 2012. Skin-prick tests, pulmonary function tests, total and specific serum IgE, serum autoantibodies, cytokines and growth factors, and flow cytometry were used to supplement clinical diagnosis of allergy, autoimmune, and infectious illnesses. Rhinitis, conjunctivitis, skin allergic disorders, and anaphylaxis were all prevalent at 26.2 per cent, 20.0 per cent, 14.8 per cent, and 1.1 per cent, respectively. Sensitization to inhalant allergens was reported in 49.0 per cent of athletes, up from 32.7 per cent in 2000 to 56.5 per cent in 2008. Food, medication, and venom allergies were found in 7.1%, 5.0%, and 2.1 per cent of athletes, respectively. Recurrent upper respiratory tract and herpes infections, an aberrant T cell subset profile, and a general down-regulation of serum cytokines with a substantially lower IFN-/IL-4 ratio were all related to a high incidence of asthma and allergies.
Chronic and severe physical activity may result in a temporary immunodepression with a preferred shift to a Th2 response, which is linked with respiratory tract problems.
