title: Stress-related sleep disturbance and polysomnographic response to caffeine.
abstract: OBJECTIVE
  To determine the sleep response to caffeine in individuals vulnerable to stress-related sleep disturbance as measured by polysomnography.
  
  
  METHODS
  Eleven healthy individuals without insomnia scoring low (4 women, mean age=32.64+/-15.46 years) and 10 healthy individuals also without insomnia scoring high (6 women, mean age=34.20+/-13.73 years) on a measure of vulnerability to stress-related sleep disturbance were studied in a laboratory protocol. A moderate-low dose of caffeine (3 mg/kg) was administered 1h prior to lights-out and compared to a counterbalanced control night with each condition separated by 1 week. Standard polysomnographic measures were assessed (i.e. total sleep time, sleep efficiency, latency to persistent sleep, and sleep stage percentages) for both control and caffeine nights.
  
  
  RESULTS
  There were no between-group differences in sleep on the control night. Importantly, individuals reporting vulnerability to stress-related sleep disturbance had significantly prolonged latency to persistent sleep in response to the caffeine challenge (interaction; P<0.05).
  
  
  CONCLUSIONS
  Normal sleepers with an identified vulnerability to stress-induced sleep disturbance exhibited greater objectively verifiable sleep-reactivity in response to a caffeine challenge compared to non-vulnerable individuals. These results suggest that the construct of individual differences in vulnerability to sleep disturbance applies to a pharmacological 'stressor' (i.e. caffeine) as well as to previously assessed stressors such as a first-night effect. This finding provides further support for generalized trait vulnerability by demonstrating a sleep disturbance to a wake-promoting pharmacological challenge in specific a priori identified individuals.
authors.affiliation: Henry Ford Hospital Sleep Disorders and Research Center, and Department of Psychiatry and Behavioral Neurosciences, Wayne State College of Medicine, Detroit, MI 48202, USA. cdrake1@hfhs.org
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Drake
authors.forename: Catherine
authors.initials: C
authors.lastname: Jefferson
authors.forename: Timothy
authors.initials: T
authors.lastname: Roehrs
authors.forename: Thomas
authors.initials: T
authors.lastname: Roth
mesh_terms: D000328:Adult; D001143:Arousal / Q000187:drug effects; D002110:Caffeine / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007206:Individuality; D008297:Male; D008875:Middle Aged; D017286:Polysomnography / Q000187:drug effects*; D012016:Reference Values; D012307:Risk Factors; D007319:Sleep Initiation and Maintenance Disorders / Q000209:etiology*; D012894:Sleep Stages / Q000187:drug effects; D013315:Stress, Psychological / Q000150:complications*
chemical_list: D002110:Caffeine