title: Functional Changes after Recombinant Human Growth Hormone Replacement in Patients with Chronic Traumatic Brain Injury and Abnormal Growth Hormone Secretion.
abstract: We explored the effects of recombinant human growth hormone (rhGH) replacement on physical and cognitive functioning in subjects with a moderate-to-severe traumatic brain injury (TBI) with abnormal growth hormone (GH) secretion. Fifteen individuals who sustained a TBI at least 12 months prior to study enrollment were identified as having abnormal GH secretion by glucagon stimulation testing (maximum GH response less than 8 ng/mL). Peak cardiorespiratory capacity, body composition, and muscle force testing were assessed at baseline and one year after rhGH replacement. Additionally, standardized neuropsychological tests that assess memory, processing speed, and cognitive flexibility, as well as self-report inventories related to depression and fatigue, were administered at baseline and 1 year after rhGH replacement. Comparison tests were performed with proper post hoc analyses. All analyses were carried out at α < 0.05. Peak O2consumption, peak oxygen pulse (estimate of cardiac stroke volume), and peak ventilation all significantly increased (p < 0.05). Maximal isometric and isokinetic force production were not altered. Skeletal muscle fatigue did not change but the perceptual rating of fatigue was reduced by ∼25% (p = 0.06). Cognitive performance did not change significantly over time, whereas self-reported symptoms related to depression and fatigue significantly improved. The observed changes suggest that rhGH replacement has a positive impact on cardiorespiratory fitness and a positive impact on perceptual fatigue in survivors of TBI with altered GH secretion.
authors.affiliation: 1 University of Texas Medical Branch , Galveston, Texas.
authors.forename: Kurt A
authors.initials: KA
authors.lastname: Mossberg
authors.affiliation: 1 University of Texas Medical Branch , Galveston, Texas.
authors.forename: William J
authors.initials: WJ
authors.lastname: Durham
authors.affiliation: 1 University of Texas Medical Branch , Galveston, Texas.|2 Transitional Learning Center , Galveston, Texas.
authors.forename: Dennis J
authors.initials: DJ
authors.lastname: Zgaljardic
authors.affiliation: 1 University of Texas Medical Branch , Galveston, Texas.
authors.forename: Charles R
authors.initials: CR
authors.lastname: Gilkison
authors.affiliation: 1 University of Texas Medical Branch , Galveston, Texas.
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Danesi
authors.affiliation: 1 University of Texas Medical Branch , Galveston, Texas.
authors.forename: Melinda
authors.initials: M
authors.lastname: Sheffield-Moore
authors.affiliation: 1 University of Texas Medical Branch , Galveston, Texas.|2 Transitional Learning Center , Galveston, Texas.
authors.forename: Brent E
authors.initials: BE
authors.lastname: Masel
authors.affiliation: 1 University of Texas Medical Branch , Galveston, Texas.
authors.forename: Randall J
authors.initials: RJ
authors.lastname: Urban
mesh_terms: D000328:Adult; D000070642:Brain Injuries, Traumatic / Q000097:blood / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D000072599:Cardiorespiratory Fitness / Q000502:physiology*; D002908:Chronic Disease; D060825:Cognitive Dysfunction / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D003863:Depression / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D005221:Fatigue / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D005260:Female; D020249:Hormone Replacement Therapy / Q000379:methods*; D019382:Human Growth Hormone / Q000008:administration & dosage / Q000097:blood* / Q000494:pharmacology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011994:Recombinant Proteins; D055815:Young Adult
chemical_list: D011994:Recombinant Proteins; D019382:Human Growth Hormone
keywords: TBI; cognitive; growth hormone; physical