Why might a dr prescribe somatropin (hgh) on a long-term use basis to a physically healthy adult with a neurological condition?

HGHJ: Hgh is used for growth failure, growth hormone deficiency, intestinal disorder (short bowel syndrome) or hiv-related weight loss or wasting.Somatropin is also used to increase height in children with a certain genetic disorder (noonan syndrome). It has also been shown to benefit those with traumatic brain injury improved intelligence, learning and performance relative to placebo.