title: Sleep changes following statin therapy: a systematic review and meta-analysis of randomized placebo-controlled polysomnographic trials.
abstract: BACKGROUND
  Statin use might be associated with an increased risk of sleep disturbances including insomnia, but the evidence regarding sleep changes following statin therapy has not been conclusive. Therefore we assessed the impact of statin therapy on sleep changes through a systematic review and meta-analysis of available randomized controlled trials (RCTs).
  
  
  METHODS
  We searched MEDLINE and SCOPUS up to October 1, 2014 to identify placebo-controlled RCTs investigating the effect of statin therapy on sleep changes. A meta-analysis was performed using either a fixed-effects or a random-effect model according to the I2 statistic. Effect size was expressed as weighted mean difference (WMD) and 95% confidence interval (CI).
  
  
  RESULTS
  Overall, the impact of statin therapy on polysomnography (PSG) indices of sleep was reported in 5 trials comprising 9 treatment arms. Overall, statin therapy had no significant effect on total sleep duration (WMD: -7.75 min, 95% CI: -18.98, 3.48, p = 0.176), sleep efficiency (WMD: 0.09%, 95% CI: -2.27, 2.46, p = 0.940), entries to stage I (WMD: 0.36, 95% CI: -0.91, 1.63, p = 0.580), or latency to stage I (WMD: -1.92 min, 95% CI: -4.74, 0.89, p = 0.181). In contrast, statin therapy significantly reduced wake time (WMD: -4.43 min, 95% CI: -7.77, -0.88, p = 0.014) and number of awakenings (WMD: -0.40, 95% CI: -0.46, -0.33, p < 0.001). Meta-regression did not suggest any correlation between changes in wake time and awakening episodes with duration of treatment and LDL-lowering effect of statins.
  
  
  CONCLUSIONS
  The results indicated that statins have no significant adverse effect on sleep duration and efficiency, entry to stage I, or latency to stage I sleep, but significantly reduce wake time and number of awakenings.
authors.affiliation: Department of Internal Diseases and Clinical Pharmacology, Medical University of Lodz, Lodz, Poland.
authors.forename: Marlena
authors.initials: M
authors.lastname: Broncel
authors.affiliation: Department of Internal Diseases and Clinical Pharmacology, Medical University of Lodz, Lodz, Poland.
authors.forename: Paulina
authors.initials: P
authors.lastname: Gorzelak-Pabiś
authors.affiliation: Biotechnology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran ; Metabolic Research Centre, Royal Perth Hospital, School of Medicine and Pharmacology, University of Western Australia, Perth, Australia.
authors.forename: Amirhossein
authors.initials: A
authors.lastname: Sahebkar
authors.affiliation: Department of Internal Diseases and Clinical Pharmacology, Medical University of Lodz, Lodz, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Serejko
authors.affiliation: Department of Functional Sciences, Discipline of Public Health, "Victor Babes" University of Medicine and Pharmacy, Timisoara, Romania.
authors.forename: Sorin
authors.initials: S
authors.lastname: Ursoniu
authors.affiliation: Department of Nephrology, Hypertension and Family Medicine, Chair of Nephrology and Hypertension, Medical University of Lodz, Lodz, Poland.
authors.forename: Jacek
authors.initials: J
authors.lastname: Rysz
authors.affiliation: Department of Epidemiology, University of Alabama at Birmingham, Birmingham, AL, USA ; Department of Functional Sciences, Discipline of Pathophysiology, "Victor Babes" University of Medicine and Pharmacy, Timisoara, Romania.
authors.forename: Maria
authors.initials: M
authors.lastname: Corina Serban
authors.affiliation: Department of Internal Diseases and Clinical Pharmacology, Medical University of Lodz, Lodz, Poland.
authors.forename: Monika
authors.initials: M
authors.lastname: Możdżan
authors.affiliation: Department of Hypertension, Chair of Nephrology and Hypertension, Medical University of Lodz, Lodz, Poland.
authors.forename: Maciej
authors.initials: M
authors.lastname: Banach
keywords: meta-analysis; polysomnography; sleep; stain therapy; statins