Growth Hormone Alters Brain Morphometry, Connectivity, Behavior in Subjects with TBI

Each year, more than 2.5 million people experience a traumatic brain injury in the United States alone. For years after a head injury, many people experience a chronic syndrome called BIAFAC. Some of the symptoms include fatigue, depression, anxiety, and trouble with sleep and memory. We’ve spent the past 20 years learning more about BIAFAC and helping people living with brain injuries. We’ve learned that traumatic brain injuries trigger a long-term reduction in growth hormone secretion and that people living with BIAFAC experience dramatic relief from their symptoms with hormone replacement therapy. The trouble is that the BIAFAC returns if the treatment stops. The treatment can be expensive and is not always covered by health insurance. With this in mind, we’re on the search to better understand BIAFAC and learn exactly how and why GH replacement works so well in order to develop new treatments. We’ve recently published a new study in the Journal of Neurotrauma that sheds some new light on this. We examined 18 people with a history of mild TBI and inadequate growth hormone secretion. The subjects received growth hormone replacement in a year-long, double-blind, placebo-controlled study and we tracked changes in physical performance, resting metabolic rate, fatigue, sleep quality, and mood. We also used functional MRI throughout the year to monitor changes in brain structure and functional connections. The study showed that growth hormone replacement was linked with increased lean body mass and decreased fat as well as reduced fatigue, anxiety, depression and sleep disturbance. We also found that these improvements were associated with better communication among brain networks that have been already linked with growth hormone deficiency. We also saw increases in both grey and white matter in frontal brain regions, the “core communications center of the brain,” that could be related to the cognitive improvements. We hope that our new findings will help people to better understand and treat this syndrome.