16,15 Hypnotic medication offers only short-term efficacy and, in the long term, may itself disrupt sleep.44,45 Hypnotic use may also lead to exacerbation

of sleep apnea and daytime carryover effects, such as sedation, delirium, falls, fractures, cognitive impairment, and anterograde amnesia46 and has been associated with increased morbidity and mortality.35,37-42 The 1991 National Institutes Inhibitors,research,lifescience,medical of Health (NIH) Consensus Conference on the Treatment of Sleep Disorders of Older People concluded that “nonsedative hypnotic approaches to improve sleep quality in the elderly population are sorely needed.”19 Pulsatile GH secretion continues with aging, but with a pattern of diminished GH pulse amplitude.4 In particular, nighttime GH secretion declines, so that there is often no longer a clear night-day GH rhythm. SWS also declines with aging, although it is unclear whether the GH decline is due to the reduction in SWS, whether SWS deteriorates because Inhibitors,research,lifescience,medical of the decline in GH, or whether both arc decreased because of a common reduction at a higher level of regulation

(eg, GHRH). Recent studies have shown that sleep is influenced by clinical extremes of GH status47,48 and that sleep can be improved in response to acute GH administration49 Inhibitors,research,lifescience,medical or Inhibitors,research,lifescience,medical stimulation of the GH-IGF-I axis using GHRH.50 Acute GHRH administration increases SWS51 and acute decreases in GH status by a GH-releasing factor antagonist decrease slow-wave amplitude and SWS duration52 in animals. Among hormones, GHRH displays the bestdocumented sleep-promoting activity and is clearly implicated in the regulation of sleep, specifically non REM sleep. GHRH hypothalamic neurons projecting

to the basal forebrain, specifically Inhibitors,research,lifescience,medical the medial preoptic area, likely act directly to increase non-REM/SWS.53 Three independent laboratories have recently reported that GHRH promotes sleep in healthy young subjects,54-58 although two older studies reported no such effect59,60 and there is some evidence to suggest that the impact of GHRH on the sleep of the elderly may be weaker.61,62 Aging, cognition, see more and somatotrophic hormones While it has been SB431542 ic50 extensively documented that significant changes in several major areas of cognitive function develop with advancing age, such declines do not develop uniformly. For example, some components of memory remain relatively intact with advancing age (eg, primary or shortterm memory) , while others do not (eg, secondary or longterm memory). A major distinction that is useful for describing those functions that are preserved versus impaired by advancing age was proposed by Cattell, ie, the concepts of crystallized versus fluid intelligence.