Neuroendocrine Dysfunction in Traumatic Brain Injury: Effects of Testosterone Therapy

This study will assess the hormonal status of men on admission to an inpatient TBI
rehabilitation program. Eighty-eight Individuals with low Testosterone (T) levels will be
randomized to receive either physiologic T therapy or placebo. Fifty-six Individuals with
sufficient levels of T will be followed as a second control group. All three groups will
undergo serial assessment of neurological function (as measured by the NIH Toolbox) and
functional independence (FIM) to correlate with hormone levels. Hormone levels will be
assessed through analysis of blood samples drawn from all participants at the time of study
screening and at two week intervals for a total of 7 blood draws during the 12 week study
period. Demographics, injury characteristics, concomitant medication usage and adverse events
will be documented by medical record review. Statistical analysis will be performed to test
study hypotheses. Findings will be disseminated at professional and consumer conferences and
in peer-reviewed journals and consumer-based publications. Results will also be made
available through the Craig Hospital website and via summary report to the Colorado TBI Trust
Fund Research Program. If T therapy is found to be effective, findings will be used as
preliminary data for a grant proposal for a multi-center trial.

Inclusion Criteria:

1. History of TBI as defined as "damage to brain tissue caused by an external mechanical
force as evidenced by loss of consciousness or post traumatic amnesia (PTA) due to
brain trauma or by objective neurological findings that can be reasonably attributed
to TBI on physical examination or mental status examination;"82

2. Moderate to severe TBI as indicated by a Glasgow Coma Scale (GCS) score of less than
or equal to 12 at emergency department admission, or post traumatic amnesia (PTA) of
greater than or equal to seven days post-injury, or radiographic evidence of
intracranial injury;

3. Continuously hospitalized from time of injury until admission for rehabilitation;

4. Enrolled in study within 6 months of TBI;

5. Receiving inpatient rehabilitation for TBI at Craig Hospital;

6. Males between the ages of 16 to 65 (inclusive);

7. Approval by attending physician;

8. Testosterone level below the assay normal range;

9. Consent to study participation

Exclusion Criteria:

10. History of any conditions that would prohibit testing contained in the NIH toolbox;

11. Non-English or non-Spanish speaking (to the extent that would limit the ability to
complete study measures);

12. History of prior psychiatric illness requiring hospitalization;

13. Prior testosterone therapy;

14. History of or current or suspected hormonally dependent cancer , including carcinoma
of the breast or prostate cancer;

15. Known hypersensitivity to any T gel ingredients including alcohol and soy products;

16. Hematocrit (HCT) greater than 55% (normal range in Colorado is up to 52) or
transaminase elevation >4x upper limit of the normal range.

17. Abnormal finding on digital rectal examination such as nodule, asymmetry, or
induration (Does not include enlarged prostate or abnormal rectal tone)

18. PSA>4.0

19. BMI <16 or >40kg/m2

20. History of untreated prolactinoma

21. History of severe heart failure or uncontrolled medical problem that would interfere
with the participant's safety in the study as determined by the investigator.