title: Growth hormone releasing hormone improves the cognition of healthy older adults.
abstract: Declines in the activity of the somatotrophic axis have been implicated in the age-related changes observed in a number of physiological functions, including cognition. Such age-related changes may be arrested or partially reversed by hormonal supplementation. We examined the effect of 6 months treatment with daily growth hormone releasing hormone (GHRH) or placebo on the cognition of a group of 89 healthy older (68.0+/-0.7) adults. GHRH resulted in improved performance on WAIS-R performance IQ (p<0.01), WAIS-R picture arrangement (p<0.01), finding A's (p<0.01), verbal sets (p<0.01) and single-dual task (p<0.04). GHRH-based improvements were independent of gender, estrogen status or baseline cognitive capacity. These results demonstrate that the age-related decline in the somatotrophic axis may be related to age-related decline in cognition. Further they indicate that supplementation of this neuro-hormonal axis may partially ameliorate such cognitive declines in healthy normal older adults and potentially in individuals with impaired cognitive function (i.e., mild cognitive impairment and Alzheimer's disease).
authors.affiliation: Department of Psychiatry and Behavioral Sciences, BB-1520D Health Science Building, University of Washington, Box 356560, 1959 NE Pacific Street, Seattle, WA 98195-6560, USA. vitiello@u.washington.edu
authors.forename: Michael V
authors.initials: MV
authors.lastname: Vitiello
authors.forename: Karen E
authors.initials: KE
authors.lastname: Moe
authors.forename: George R
authors.initials: GR
authors.lastname: Merriam
authors.forename: Giuliana
authors.initials: G
authors.lastname: Mazzoni
authors.forename: David H
authors.initials: DH
authors.lastname: Buchner
authors.forename: Robert S
authors.initials: RS
authors.lastname: Schwartz
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000188:drug therapy*; D005260:Female; D013007:Growth Hormone-Releasing Hormone / Q000627:therapeutic use*; D006801:Humans; D007361:Intelligence Tests / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D013997:Time Factors
chemical_list: D013007:Growth Hormone-Releasing Hormone