post-traumatic hypopituitarism is found in 40% of those with TBI. The severity does correlate with the increased likelihood of developing PTHP. Isolated deficiencies have been found in PTHP.
The majority of people with PTHP after TBI remain undiagnosed. The current thought, is that 25% of those with TBI have at least one pituitary hormone deficiency. It does not have to be total pituitary failure. Deficiencies can be isolated.