Boxing as a sport activity associated with isolated GH deficiency

Abstract

Traumatic brain injury (TBI) has long been known as a cause of hypopituitarism, and it is characterized by a high prevalence of neuroendocrine abnormalities. Boxing, one of the most common combative sports, may also result in TBI. As far as we know, pituitary functions including GH status have not been investigated in boxers. Therefore, in this preliminary study, we have assessed the pituitary functions in boxers. Eleven actively competing or retired male boxers with a mean age of 38.0 +/- 3.6 yr and 7 age-, sex- and BMI-matched healthy non-boxing controls were included in the study. Biochemical and basal hormonal parameters including IGF-I levels were measured. To assess GH secretory status in boxers and healthy controls, GHRH (1 microg/kg)+GHRP-6 (1 microg/kg) test was performed. After GHRH+GHRP-6 test, mean peak GH level in boxers and in controls were 10.9 +/- 1.7 and 41.4 +/- 6.7 microg/l, respectively (p < 0.05). Peak GH levels in 5 (45%) boxers were found to be lower than 10 microg/l and considered as severe GH deficient. In the control group, mean IGF-1 levels (367 +/- 18.8 ng/ml) were significantly higher than that obtained in boxers (237 +/- 23.3 ng/dl) (p < 0.01). All the other pituitary hormones were normal including ADH as no signs and symptoms of diabetes insipidus. There was a significant negative correlation between peak GH levels and boxing duration, and between peak GH levels and number of bouts. In conclusion, we think that boxing is a cause of TBI, and GH deficiency is very common among boxers. Further studies including large number of boxers, both professional and amateur, are needed to clarify pituitary dysfunction in boxers.

Prevalence of Pituitary Hormone Dysfunction, Metabolic Syndrome, and Impaired Quality of Life in Retired Professional Football Players: A Prospective Study

“…19 Studies in kickboxers and retired boxers also have reported relatively high rates of hypopituitarism; in one report, isolated GH deficiency (GHD) was documented in 45% of subjects, and the severity of GHD correlated with the number of bouts and boxing career duration. [20][21][22][23] In another study by Bondanelli and colleagues, chronic hypopituitarism was observed in 37% of mTBI patients. 10 Given the high rate of repetitive head impact and recurrent concussion in professional football players, and the depression, poor QoL, and obesity that are relatively common among NFL retirees, we hypothesized that pituitary dysfunction could be a contributing factor to their poor physical and mental health status.…”

“…47 Small case series in boxing and kickboxing have shown a high rate of GHD, and one case report highlighted the association between repeat concussion in an adolescent athlete and subsequent anterior hypopituitarism. 15,19,[21][22][23]48 Quality of life, erectile dysfunction, metabolic syndrome, and obesity…”

Sports-related chronic repetitive head trauma as a cause of pituitary dysfunction

“…To our knowledge, only 3 studies and 1 case report investigated the link between pituitary dysfunction and sports-related concussion. 35,38,65,67 Three of these studies were conducted by the same medical team. 38,65,67 The studies only concern 3 sports-boxing, 38,67 kickboxing, 65 and soccer 35 -that are obviously associated with chronic mild TBI.…”

“…The first report of pituitary function in boxers was published in 2004 by Kelestimur et al 38 In this preliminary study, the authors included 11 actively competing or retired male amateur boxers and investigated their GH status compared to a control group. A GH deficiency was found in 45% of these amateur boxers.…”

“…Recent studies have demonstrated that sports-related repetitive head trauma might induce pituitary dysfunction, and in particular, isolated GH deficiency. 38,65,67 The aim of this paper was to summarize the best evidence for understanding the pathophysiological mechanisms and to discuss current data and recommendations on sports-related repetitive head trauma as a cause of hypopituitarism.…”