Year: 2012
Type: dissertation
Study design: Observational Study
Abstract: Introduction: Respiratory tract symptoms (RTS), common in athletes during heavy training and \nafter events, result in impaired readiness for events and race times. Since the 1980’s exercise \nimmunologists have investigated the aetiological factors surrounding the development of \nexercise induced RTS in order to develop effective preventative strategies. A number of theories \nhave been put forward and explored, such as increased susceptibility to infection, ‘run-away’ \ninflammatory response and reactivation of prior viral infection. It has been suggested that the \nmechanisms producing exercise induced inflammation could potentiate allergic responses in \nsensitized individuals and recently allergic response has been proposed as a potential contributor \nto exercise induced RTS. Certainly allergic reactions can produce a range of respiratory \nsymptoms; however the relationship between allergic sensitization, allergic reaction and the \nincidence of post-exercise RTS has not been well defined. \nObjectives: The primary objective of this study was to document the incidence of RTS for two \nweeks before and two weeks after a three-day trail run and relate these to the general systemic \nand salivary immunological profile as well as atopic status of the participants. The secondary \nobjective was to validate the use of the Phadiatop® assay as a predictor of allergy-associated \npost-race RTS in trail runners. \nStudy Design and Methods: The study formed part of a larger, descriptive field study \nexamining the physiological responses of trail runners during the Three Cranes Challenge, a \nmulti-day 95 km event divided into three stages, in Karkloof, KwaZulu-Natal. Outcome \nmeasures examined included self- reported RTS over a 31 day period (pre, during and post race), \nas well as pre-race Phadiatop® status, salivary IgA (sIgA) concentrations and changes in \nconcentrations of serum IgE (sIgE), cortisol, high sensitivity C-Reactive Protein (hs-CRP) and \ndifferential leukocyte counts. The haematological and salivary parameters were obtained at 8 \ntime points before, during and after the event. \n \nA convenience sample of 22 individuals was used and two separate analyses were conducted on \nthe data. The inclusion criteria of the first analysis were met by 14 participants. In this analysis, \nthe incidence of RTS was related to each participant’s general immunological profile. Sixteen of \nthe subjects met the inclusion criteria for the second analysis, in which their Phadiatop® status \nwas related to their sIgE and blood eosinophil and basophil concentrations in order to establish \nthe validity of the Phadiatop® assay in predicting the development of allergy–associated postexercise \nRTS in trail runners. \nResults: In the first analysis, 78.6 % (n=11) of subjects met the criteria for positive diagnosis of \nupper respiratory symptoms (URS) during the two week post-race period. In four subjects (36.4 \n%), URS appeared to be of inflammatory origin, but these were not linked to systemic markers of \nan allergic response. Of the URS positive subjects, six (54.5 %) presented with markers of \ninfection, three (27.3 %) with markers of a de novo infection and three (27.3%) with a profile \nsuggestive of reactivation of previous infection. Of those presenting with markers of infection \n66.7 % (n=4) had concomitantly elevated levels of IgE suggestive of allergic response. There \nwas, however, no evidence of isolated allergic reaction independent of other causes amongst the \nsymptomatic subjects. \nIn the second analysis, 75% (n=12) of runners presented with post-race RTS and seven of these \nwere Phadiatop® positive. In four of the Phadiatop® positive RTS subjects, symptoms appeared \nto be of allergic origin. Although total IgE concentrations were significantly higher (p< 0.01) in \nPhadiatop® positive group, there was no significant difference between the eosinophil and \nbasophil concentrations or post-race RTS of the positive and negative groups (p>0.05). Of the \nfour subjects who did not develop RTS, three were Phadiatop® positive. \nConclusion: Respiratory tract symptoms in trail runners have a multi-factorial aetiology. A link \nbetween concurrent markers of an allergic response and infection is common in symptomatic \ntrail runners. The Phadiatop® assay does not accurately predict the incidence of allergic postexercise \nRTS in trail runners.
Authors: Dick de Waard, Anton Hans.
Language: English
Subfield: Pulmonary and Respiratory Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W2241374838