title: Persistent fatigue in young athletes: measuring the clinical course and identifying variables affecting clinical recovery.
abstract: The objective of this paper is to measure the clinical course (months) in young athletes with persistent fatigue and to identify any covariates affecting the duration of recovery. This was a prospective longitudinal study of 68 athletes; 87% were elite (42 males, 26 females), aged 20.5±3.74 years (SD), who presented with the symptom of persistent fatigue. The collective duration to full clinical recovery was estimated using Kaplan-Meier product-limit curves, and covariates associated with prolonging recovery were identified from Cox proportional hazard models. The median recovery was 5 months (range 1-60 months). The range of presenting symptom duration was 0.5-36 months. The covariates identified were an increased duration of presenting symptoms [hazard ratio (HR), 1.06; 95% confidence interval (CI), 1.02-1.12; P=0.005] and the response of serum cortisol concentration to a standard exercise challenge (HR, 1.92; 95% CI, 1.09-3.38; P=0.03). Delay in recovery was not associated with categories of fatigue that included medical, training-related diagnoses, or other causes. In conclusion, the fatigued athlete represents a significant clinical problem with a median recovery of 5 months, whose collective clinical course to recovery can be estimated by Kaplan-Meier curves and appears to be a continuum.
authors.affiliation: School of Human Movement Studies, University of Queensland, Brisbane, Qld, Australia. admin@sportnmovementcentre.com
authors.forename: S
authors.initials: S
authors.lastname: Locke
authors.forename: M
authors.initials: M
authors.lastname: Osborne
authors.forename: P
authors.initials: P
authors.lastname: O'Rourke
mesh_terms: D056352:Athletes; D015415:Biomarkers / Q000032:analysis; D005221:Fatigue / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D016016:Proportional Hazards Models; D011446:Prospective Studies; D020127:Recovery of Function; D012307:Risk Factors; D013997:Time Factors; D055815:Young Adult
chemical_list: D015415:Biomarkers