Sports-related Chronic Repetitive Head Trauma as a Cause of Pituitary Dysfunction

Julie Dubourg, M.D.; Mahmoud Messerer, M.D.


Neurosurg Focus. 2011;31(5):e2 

In This Article

Hypopituitarism and Sports

As mentioned earlier, sports-related concussion could be considered as a subgroup of mild TBI. Also, TBI is one of the most important public health problems,[70] and may be associated with pituitary secretion dysfunction, which may contribute to long-term physical, cognitive, and psychological disability.

Almost all of the studies regarding the relationship between TBI and sports published so far in the literature are based on neuropsychological or radiological assessment, and no neuroendocrine changes are investigated. There is a paucity of data regarding the association between sports and hypopituitarism. 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. The mean IGFI levels in boxers (237 ± 23.3 ng/ml) were significantly lower than in the control group (367 ± 18.2 ng/ml). There was a significant negative correlation both between peak GH levels and boxing duration and between peak GH levels and number of bouts.

In 2007, Tanriverdi et al.[65] investigated the GH status of 22 amateur kickboxers compared with a control group. The serum IGF-I level was significantly lower in kickboxers (276.5 ± 25.9 ng/ml) than in the control group (346.9 ± 20.9 ng/ml). Of the 22 amateur kickboxers, 22.7% had a GH deficiency and 9.1% had an ACTH deficiency. There were negative correlations between serum IGF-I level and age, length of time the athlete has participated in sports, and number of bouts.

Ives et al.[35] reported a case of a 16-year-old high-level junior soccer player who had experienced 4 episodes of mild TBI at different time points over a 4-month period. The first 3 traumas were considered by the athlete to be minor, and thus were not reported to medical personnel. The fourth trauma was a medically diagnosed concussion. Over the next year, the patient presented with failure of physical growth, stagnation of soccer abilities and physical skills, and lower energy levels. After a full battery of endocrine tests, the diagnosis was compatible with hypopituitarism (GH, ACTH, and thyroid-stimulating hormone [TSH] deficiencies).

In 2008, Tanriverdi et al.[67] investigated the pituitary function in 61 retired or active amateur boxers. The findings were similar to those in previous studies, with 15% and 8% of GH and ACTH deficiency, respectively, among boxers. An interesting fact is the lower rate of hypopituitarism in active boxers (18%) than in retired boxers (47%).

All of these findings suggest that sports-related repetitive TBI has a cumulative effect on the development of pituitary dysfunction.