Age-Related Sleep Impairment - Treatment w/GHRH

To examine the effects of synthetic growth hormone releasing hormone (GHRH) versus placebo on the sleep quality, 24-hour secretory pattern of growth hormone (GH), and insulin-like growth factor 1 (IGF-1) concentrations of 40 healthy older men and 40 healthy older women on estrogen replacement therapy (ERT). To determine if augmenting the GH-IGF-1 axis can improve the objective sleep quality of the older population. To determine if treatment-related changes in sleep quality are correlated with changes in GH and/or IGF-1 concentrations. Nearly 40% of the geriatric population complain of poor sleep quality, a complaint that is validated by objective findings. The physiological consequences of age-impaired sleep are poorly understood, but may include damped circadian rhythms and impaired anabolic hormone status. Poor sleep may also account for the disproportionate prescription of sedative hypnotics to older adults which may exacerbate sleep apnea, lead to daytime carryover effects such as sedation, falls, fractures, cognitive impairment, and anterograde amnesia, and has been associated with increased morbidity and mortality. The recent NIH Consensus Conference on the Treatment of Sleep Disorders in Older People concluded that nonsedative interventions to improve sleep quality in the elderly population are obviously needed. One such intervention may be stimulation of the GH-IGF-1 axis by GHRH administration. Clinical evidence indicates sleep quality can be affected by extremes of GH status and several recent studies report acute GHRH administration improves sleep quality in young men. We have recently demonstrated that measures of sleep quality correlate with basal IGF-1 concentrations in healthy older men and ERT women. 40 healthy older men and 40 healthy older women on ERT receive either GHRH or placebo.