title: Melatonin and Sleep-Wake Rhythms before and after Ocular Lens Replacement in Elderly Humans.
abstract: Light of short wavelengths has been shown to play a key role in non-image forming responses. Due to aging, the ocular lens becomes more yellow reducing the transmission of short wavelengths in the elderly. In the present study, we make use of cataract surgery to investigate the effects of a relative increase of short wavelength transmission on melatonin- and sleep-wake rhythms (N = 14). We observed, on average, a delay of the sleep-wake and the nocturnal melatonin rhythms after cataract surgery. This delay is tentatively attributed to a relatively large increase of light transmittance in the evening hours more than an increase of the already relatively high light intensities found in the daytime. The later phase that we observed after cataract surgery (clear lens) as compared to the earlier phase observed before cataract (yellowish lens) is in agreement with the general later phase reported in the young (clear lens) population.
authors.affiliation: Department of Chronobiology, GeLifes, University of Groningen, Groningen 9747 AG, The Netherlands. marina.gimenez@gmail.com.|Chrono@Work B.V., Groningen 9747 AT, The Netherlands. marina.gimenez@gmail.com.
authors.forename: Marina
authors.initials: M
authors.lastname: Giménez
authors.affiliation: Department of Chronobiology, GeLifes, University of Groningen, Groningen 9747 AG, The Netherlands. d.g.m.beersma@rug.nl.
authors.forename: Domien
authors.initials: D
authors.lastname: Beersma
authors.affiliation: Department of Chronobiology, GeLifes, University of Groningen, Groningen 9747 AG, The Netherlands. s.daan@rug.nl.
authors.forename: Serge
authors.initials: S
authors.lastname: Daan
authors.affiliation: Department of Ophthalmology, University Medical Centre Groningen, Groningen 9713 GZ, The Netherlands. vdpol@me.com.
authors.forename: Bert van der
authors.initials: Bv
authors.lastname: Pol
authors.affiliation: Department of Ophthalmology, University Medical Centre Utrecht, Utrecht 3584 CX, The Netherlands. mkanis@tergooi.nl.
authors.forename: Martijn
authors.initials: M
authors.lastname: Kanis
authors.affiliation: Department of Ophthalmology, University Medical Centre Utrecht, Utrecht 3584 CX, The Netherlands.
authors.forename: Dick
authors.initials: D
authors.lastname: van Norren
authors.affiliation: Department of Chronobiology, GeLifes, University of Groningen, Groningen 9747 AG, The Netherlands. m.c.m.gordijn@rug.nl.|Chrono@Work B.V., Groningen 9747 AT, The Netherlands. m.c.m.gordijn@rug.nl.
authors.forename: Marijke
authors.initials: M
authors.lastname: Gordijn
keywords: aging; cataract surgery; humans; melatonin rhythms; ocular lens; sleep-wake rhythms