[Skip to Navigation]
Comment & Response
April 6, 2020

Uncertain Association Between Concussion and Hypogonadism—Reply

Author Affiliations
  • 1Football Players Health Study, Harvard Medical School, Boston, Massachusetts
  • 2Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
  • 3Neuroendocrine Unit, Department of Medicine, Massachusetts General Hospital, Boston
  • 4Harvard Medical School, Boston, Massachusetts
JAMA Neurol. 2020;77(6):774-775. doi:10.1001/jamaneurol.2020.0476

In Reply We thank Lopez and Ghuman for their comments about our study demonstrating significant associations between concussion symptoms and self-reported low testosterone levels or erectile dysfunction (ED) among former professional US-style football players.1

While we agree that the evidence of association between concussion and pituitary dysfunction is sparse, the published literature on this subject does have substantial clinical relevance. At least 2 studies have found pituitary dysfunction to occur in 29% to 38% of patients with mild traumatic brain injury (TBI),2,3 and 12% to 14% of the patients with mild TBI specifically showed hypogonadism years after injury. The US Centers for Disease Control and Prevention reports that 1.5 million Americans experience a head injury each year and that 75% of those injuries are considered mild (eg, concussion).4 Therefore, if these estimates are accurate, every year more than 400 000 and 150 000 Americans are at risk for pituitary dysfunction and hypogonadism, respectively, subsequent to mild TBI.

Add or change institution