La santé cardiorespiratoires de l'athlète d'élite : principales pathologies et mécanismes de développement

La prévalence élevée de problèmes respiratoires chez les athlètes rapportée dans la littérature et observée dans la pratique clinique, ainsi que l'importance du dépistage des problèmes cardiovasculaires chez les athlètes nous a amenés à évaluer la prévalence de ces différents problèmes cardiorespiratoires chez les athlètes d'endurance de différents sports de la région de Québec et de Chaudière-Appalaches. Nos études ont permis d'évaluer les effets de l'entraînement intensif et de facteurs environnementaux sur la fonction respiratoire et cardiovasculaire des athlètes de haut niveau et d'analyser certains mécanismes pouvant expliquer les anomalies observées. Nos résultats ont principalement démontré une forte prévalence d'asthme induit par l'exercice, de toux à l'effort chez les athlètes d'hiver, ainsi que quelques conditions cardiaques particulières, dont l'hypertension artérielle systémique de repos et d'effort chez les athlètes masculins. À la suite d'une revue de littérature portant sur les effets de l'air froid sur la fonction respiratoire des athlètes qui pratiquent des sports d'hiver, nous avons voulu évaluer si l'on peut observer une variation saisonnière de la réactivité et de l'inflammation bronchique qui aurait pu expliquer les symptômes respiratoires fréquemment rapportés par ces athlètes. Nos résultats suggèrent qu'il n'y a pas de variation saisonnière de la réactivité ou de l'inflammation bronchique chez ces athlètes. Par contre, une légère diminution significative de la fonction pulmonaire est observée en période hivernale, comparativement à l'été et à l'automne, et celle-ci est associée à une atteinte de l'épithélium bronchique. La toux post-exercice étant le symptôme le plus fréquemment rapporté par les athlètes d'endurance pratiquant des sports d'hiver, nous avons évalué si le réflexe tussigène de ces athlètes pouvait être augmenté par l'inhalation de grands volumes d'air froid lors de l'entraînement hivernal. Nos résultats ont démontré que les athlètes avaient plus de toux postexercice que les sujets témoins. Par contre, nous n'avons pas observé une augmentation du réflexe tussigène pendant la saison hivernale. Nous avons par ailleurs évalué s'il y avait des différences de tension artérielle au repos et à l'effort, de variabilité cardiaque et de profil lipidique entre une période de repos et une période d'entraînement intense chez un groupe d'athlètes. Nos résultats suggèrent que la variabilité cardiaque et la tension artérielle à l'effort sont augmentées en période d'entraînement. Une variabilité cradiaque basse est associée à un risque accru de problèmes cardiaques, tandis qu'une variabilité cardiaque augmentée est plutôt un facteur cardioprotecteur. La mesure de la variabilité cardiaque peut servir d'indice sur l'état d'entraînement. De plus, les athlètes avec une réponse hypertensive à l'effort ont des tensions artérielles de repos plus élevées, quoiqu'encore normales, en plus d'une réduction des facteurs protecteurs du profil lipidique (HDL), en comparaison avec les athlètes qui ont une réponse normotensive à l'effort.The high prevalence of cardiorespiratory problems in athletes reported in the literature and observed in our clinical practice, as well as the importance of cardiovascular screening in athletes lead us to evaluate the prevalence of different cardiorespiratory condition in endurance athletes of Quebec and Chaudiere-Appalaches area. Our studies allowed to assess the effect of intense training and environmental factors on respiratory and cardiovascular function in high level athletes as well as analyzed some mechanisms that could explain these particular cardiorespiratory conditions. Our results mainly showed a high prevalence of exercise-induced asthma, post-exercise cough in winter endurance athletes, and few cardiac abnormalities, such as arterial hypertension at rest and during exercise. Following a literature review on the effects of cold air on lung function of athletes practicing winter sports, we have evaluated whether there was a seasonal variation in the airway responsiveness and airway inflammation which could explain the frequent respiratory symptoms that are reported by these athletes. Our results suggest that there is no seasonal variation in airway responsiveness or airway inflammation in these athletes. However, a significant decrease in lung function was observed during the winter compared to summer and fall time. It seems to be associated with epithelial damage which was significantly higher in the winter time. Post-exercise cough being the symptom most frequently reported by endurance athletes practicing winter sports, we assessed whether the cough reflex could be increased by the inhalation of large volumes of cold air during winter time in these athletes. Our results showed that athletes had more post-exercise cough (1 hour after and up to 8 hours after exercise) than control subjects. However, we have not observed an increase in the cough reflex during the winter season. This has therefore led us to assess whether there were differences in resting and exercise blood pressure, heart rate variability and lipid profile between a resting period and a training period in a group of athletes. Our results suggest that heart rate variability and exercise blood pressure are increased during training period. In addition, athletes with an hypertensive response to exercise have higher resting blood pressure but within normal limits, as well as lowered values of protective factors of lipid profile (decrease in HDL) than those with a exercise normotensive response

Bronchial challenges and respiratory symptoms in elite swimmers and winter sport athletes: Airway hyperresponsiveness in asthma: its measurement and clinical significance

International audienceThis study was aimed at the following: (1) the prevalence of airway hyperresponsiveness (AHR) and exercise-induced bronchoconstriction (EIB) in swimmers and winter sport athletes according to the previously recommended regulatory sport agencies criteria, (2) the relationship between respiratory symptoms and AHR/EIB, (3) the impact of the chosen cutoff value for AHR on its prevalence, and (4) the effect on the prevalence of the positive eucapnic voluntary hyperpnea (EVH) test of using the highest vs the lowest spirometric post-EVH values to calculate the magnitude of the airway response. We compared the prevalence of respiratory symptoms with responses to methacholine challenge and EVH in 45 swimmers, 45 winter sport athletes, and 30 controls. Two methacholine challenge cutoffs for AHR were analyzed: <or= 4 mg/mL (the sport agencies' criteria for AHR) and <or= 16 mg/mL. Sixty percent of swimmers, 29% of winter sport athletes, and 17% of controls had evidence of EIB or AHR (with the <or= 4 mg/mL criteria). Among athletes with a methacholine provocative concentration inducing a 20% decrease in the FEV(1) between 4 and 16 mg/mL, 43% of swimmers and 100% of winter sport athletes were symptomatic (P < .05). Prevalence of positive EVH tests were 39% in swimmers, 24% in winter sport athletes, and 13% in controls when the highest FEV(1) value measured at each time point post-EVH was used to identify maximal response for calculation of airway response, although these prevalences were higher if we used the lowest value. This study suggests that AHR/EIB is frequent in swimmers, whereas the frequently reported respiratory symptoms in winter sport athletes are often not related to AHR/EIB. Furthermore, the choice of methods for assessing methacholine challenge and EVH responses influences the prevalences of AHR and EIB.Trial registration: clinicaltrials.gov; Identifier NCT 00686491 and NCT 00686452.Trial registration: ClinicalTrials.gov NCT00686452 NCT00686491

Serum and sputum MMP-9/TIMP-1 in winter sports athletes and swimmers: relationships with airway function

International audienc

A preliminary study on assessment of lead exposure in competitive biathletes: and its effects on respiratory health

Aim: In this preliminary study, we aimed to assess the blood lead level (BLL) in biathletes compared to cross-country skiers, and to look at the effects on airway function, responsiveness, allergic sensitization and the report of training-induced respiratory symptoms. Methods: Eleven biathletes (19 ± 2 years old, sex: 6M:4F) and 12 cross-country skiers (18 ± 3 years old, sex: 4M:8F) had a blood sample, spirometry, bronchial provocation test to Methacholine, skin prick tests, and induced sputum. Biathletes performed the tests within 3 h after a 90 to 120 min shooting session (150 ± 45 bullets fired). Results: Lung function, airway responsiveness, sensitization to common airborne allergens, and the report of training-induced respiratory symptoms were not different between both groups of winter sport athlete. BLL was significantly higher in biathletes vs. cross-country skiers (geometric mean [95%CI]: 2.15 [1.37–2.94] μg/dL vs. 0.85 [0.81–0.89] μg/dL, respectively, p 5 μg/dL). Significant correlations were observed in biathletes only between BLL and FEV1 and FVC in absolute value (r = 0.69, p = 0.02 and r = 0.69, p = 0.02, respectively). Conclusion: Despite higher BLL in biathletes, no difference in atopy, respiratory function or symptoms was observed with cross-country skiers in our experimental conditions

Perception of Bronchoconstriction Following Methacholine and Eucapnic Voluntary Hyperpnea Challenges in Elite Athletes

International audienceObjective: Self-reported respiratory symptoms are poor predictors of exercise-induced bronchoconstriction (EIB) in athletes. The objective of this study was to determine whether athletes have an inadequate perception of bronchoconstriction.Methods: One hundred thirty athletes and 32 nonathletes completed a standardized questionnaire and underwent eucapnic voluntary hyperpnea (EVH) and methacholine inhalation test. Perception scores were quoted on a modified Borg scale before each spirometry measurement for cough, breathlessness, chest tightness, and wheezing. Perception slope values were also obtained by plotting the variation of perception scores before and after the challenges against the fall in FEV1 expressed as a percentage of the initial value [(perception scores after - before)/FEV1].Results: Up to 76% of athletes and 68% of nonathletes had a perception score of ≤0.5 at 20% fall in FEV1 following methacholine. Athletes with EIB/airway hyperresponsiveness (AHR) had lower perception slopes to methacholine than nonathletes with asthma for breathlessness only (P=.02). Among athletes, those with EIB/AHR had a greater perception slope to EVH for breathlessness and wheezing (P=.02). Female athletes had a higher perception slope for breathlessness after EVH and cough after methacholine compared with men (P<.05). The age of athletes correlated significantly with the perception slope to EVH for each symptom (P<.05).Conclusions: Minimal differences in perception of bronchoconstriction-related symptoms between athletes and nonathletes were observed. Among athletes, the presence of EIB/AHR, older age, and female sex were associated with slightly higher perception scores