title: The effect of blue-blocking and neutral intraocular lenses on circadian photoentrainment and sleep one year after cataract surgery.
abstract: OBJECTIVE
  To compare the long-term effect on circadian photoentrainment and sleep in patients implanted with neutral and blue-blocking intraocular lenses 1 year after cataract surgery.
  
  
  METHODS
  Randomized, controlled trial involving 67 patients with age-related cataract. Intervention was cataract surgery with implantation of either a neutral or a blue-blocking intraocular lens (IOL). Main outcome was activation of the intrinsically photosensitive retinal ganglion cells (ipRGC) measured by chromatic pupillometry. The circadian rhythm was analysed by 24-hr melatonin profiles and actigraphy; the latter was also used to determine objective sleep quality. The Pittsburgh Sleep Quality Index determined subjective sleep quality.
  
  
  RESULTS
  One year after surgery, peak melatonin concentration was 3.3 pg/ml (95% CI, 2-5.5) corresponding to 50% lower for the participants allocated to blue-blocking IOLs compared with participants allocated to neutral IOLs. Compared with preoperative levels, the ipRGC response had increased by 13.7% (95% confidence interval [CI], 3.2-22.6) 1 year after surgery. Objective sleep quality was also improved as the time of wakefulness after sleep onset had improved by 5 min (95% CI, 1-10) for the entire population while sleep efficiency had increased by two percentage points (95% CI, 0.42-3.65) although exclusively, for the participants allocated to blue-blocking IOLs.
  
  
  CONCLUSIONS
  Blue-blocking IOLs increased sleep efficiency but lowered nocturnal melatonin secretion compared with neutral IOLs. Cataract surgery improved the response of ipRGCs and sleep quality. However, the effect of cataract surgery on sleep quality may be unrelated to circadian photoentrainment.
authors.affiliation: Department of Ophthalmology, Center of Head and Orthopedics, Rigshospitalet, Glostrup, Denmark.|Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Adam Elias
authors.initials: AE
authors.lastname: Brøndsted
authors.affiliation: Department of Ophthalmology, Naestved Sygehus, Naestved, Denmark.
authors.forename: Birgitte
authors.initials: B
authors.lastname: Haargaard
authors.affiliation: Department of Ophthalmology, Center of Head and Orthopedics, Rigshospitalet, Glostrup, Denmark.
authors.forename: Birgit
authors.initials: B
authors.lastname: Sander
authors.affiliation: Department of Ophthalmology, Center of Head and Orthopedics, Rigshospitalet, Glostrup, Denmark.|Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Henrik
authors.initials: H
authors.lastname: Lund-Andersen
authors.affiliation: Department of Ophthalmology, Center of Head and Orthopedics, Rigshospitalet, Glostrup, Denmark.|Danish Center for Sleep Medicine, Clinical Neurophysiology, Center of Neurology, Rigshospitalet, Glostrup, Denmark.
authors.forename: Poul
authors.initials: P
authors.lastname: Jennum
authors.affiliation: Department of Ophthalmology, Center of Head and Orthopedics, Rigshospitalet, Glostrup, Denmark.
authors.forename: Line
authors.initials: L
authors.lastname: Kessel
mesh_terms: D000368:Aged; D002387:Cataract Extraction; D002940:Circadian Rhythm / Q000502:physiology*; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007910:Lenses, Intraocular; D008027:Light; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D011474:Prosthesis Design; D019591:Pseudophakia / Q000503:physiopathology*; D012890:Sleep / Q000502:physiology*
keywords: actigraphy; cataract; circadian photoentrainment; melatonin; pupillometry