RT Journal Article SR Electronic T1 Risk factors associated with acute respiratory illnesses in athletes: a systematic review by a subgroup of the IOC consensus on ‘acute respiratory illness in the athlete’ JF British Journal of Sports Medicine JO Br J Sports Med FD BMJ Publishing Group Ltd and British Association of Sport and Exercise Medicine SP 639 OP 650 DO 10.1136/bjsports-2021-104795 VO 56 IS 11 A1 Derman, Wayne A1 Badenhorst, Marelise A1 Eken, Maaike A1 Gomez-Ezeiza, Josu A1 Fitzpatrick, Jane A1 Gleeson, Maree A1 Kunorozva, Lovemore A1 Mjosund, Katja A1 Mountjoy, Margo A1 Sewry, Nicola A1 Schwellnus, Martin YR 2022 UL http://bjsm.bmj.com/content/56/11/639.abstract AB Objective To review risk factors associated with acute respiratory illness (ARill) in athletes, including non-infectious ARill and suspected or confirmed acute respiratory infections (ARinf).Design Systematic review.Data sources Electronic databases: PubMed-Medline, EbscoHost and Web of Science.Eligibility criteria Original research articles published between January 1990 and July 2020 in English were searched for prospective and retrospective full text studies that reported quantitative data on risk factors associated with ARill/ARinf in athletes, at any level of performance (elite/non-elite), aged 15–65 years.Results 48 studies (n=19 390 athletes) were included in the study. Risk factors associated with ARill/ARinf were: increased training monotony, endurance training programmes, lack of tapering, training during winter or at altitude, international travel and vitamin D deficits. Low tear-(SIgA) and salivary-(IgA) were immune biomarkers associated with ARill/ARinf.Conclusions Modifiable training and environmental risk factors could be considered by sports coaches and athletes to reduce the risk of ARill/ARinf. Clinicians working with athletes can consider assessing and treating specific nutritional deficiencies such as vitamin D. More research regarding the role and clinical application of measuring immune biomarkers in athletes at high risk of ARill/ARinf is warranted.PROSPERO registration number CRD42020160928.