title: Growth hormone deficiency due to sports-related head trauma is associated with impaired cognitive performance in amateur boxers and kickboxers as revealed by P300 auditory event-related potentials.
abstract: OBJECTIVE
  It has been recently reported that boxing and kickboxing may cause pituitary dysfunction, GH deficiency in particular. The strong link between poor cognitive performance and GH deficiency due to causes other than head trauma and the improvement of cognitive function after GH replacement therapy have been previously shown. P300 auditory event-related potential (ERP) measure is widely used to evaluate cognitive performance. In this study, we investigated the relation between the GH-IGF-I axis and cognitive performance in boxers and kickboxers.
  
  
  METHODS
  Forty-one actively competing or retired male boxers (n: 27) and kickboxers (n: 14) with a mean age of 29·04 ± 9·30 year and 14 age- and education-matched healthy male controls were included in the study. For neuropsychological tests, the mini-mental state examination (MMSE) and Quality of Life Assessment of GH Deficiency in Adults (QoL-AGHDA) questionnaires were administered. Moreover, cognitive performance was evaluated according to P300 ERPs.
  
  
  RESULTS
  Nine of 41 (21·9%) athletes had GH deficiency. P300 amplitudes were lower at all electrode sites in the GH-deficient group than in controls, and the differences were statistically significant at Fz and Oz electrode sites (P < 0·05). When GH-deficient athletes were compared with GH-sufficient athletes, the P300 amplitudes were lower at all electrode sites in the GH-deficient group; these differences were statistically significant at Fz, Pz and Cz electrode sites (P < 0·05). In all athletes, there were significant negative correlations between IGF-I levels vs P300 latencies, and there were significant positive correlations between IGF-I levels vs P300 amplitudes (P < 0·05).
  
  
  CONCLUSIONS
  This study provides the first electrophysiological evidence for the close relation between the P300 ERPs and the GH-IGF-I axis in boxers and kickboxers.
authors.affiliation: Department of Endocrinology, Erciyes University Medical School, Kayseri, Turkey. fatihtan@erciyes.edu.tr
authors.forename: Fatih
authors.initials: F
authors.lastname: Tanriverdi
authors.forename: Cem
authors.initials: C
authors.lastname: Suer
authors.forename: Hande
authors.initials: H
authors.lastname: Yapislar
authors.forename: Ismail
authors.initials: I
authors.lastname: Kocyigit
authors.forename: Ahmet
authors.initials: A
authors.lastname: Selcuklu
authors.forename: Kursad
authors.initials: K
authors.lastname: Unluhizarci
authors.forename: Felipe F
authors.initials: FF
authors.lastname: Casanueva
authors.forename: Fahrettin
authors.initials: F
authors.lastname: Kelestimur
mesh_terms: D000328:Adult; D001914:Boxing; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000097:blood* / Q000209:etiology*; D006259:Craniocerebral Trauma / Q000097:blood / Q000150:complications*; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D019382:Human Growth Hormone / Q000097:blood / Q000172:deficiency*; D006801:Humans; D008297:Male; D013177:Sports; D055815:Young Adult
chemical_list: D019382:Human Growth Hormone