title: Light therapy for better mood and insulin sensitivity in patients with major depression and type 2 diabetes: a randomised, double-blind, parallel-arm trial.
abstract: BACKGROUND
  Major depression and type 2 diabetes often co-occur. Novel treatment strategies for depression in type 2 diabetes patients are warranted, as depression in type 2 diabetes patients is associated with poor prognosis and treatment results. Major depression and concurrent sleep disorders have been related to disturbances of the biological clock. The biological clock is also involved in regulation of glucose metabolism by modulating peripheral insulin sensitivity. Light therapy has been shown to be an effective antidepressant that 'resets' the biological clock. We here describe the protocol of a study that evaluates the hypothesis that light therapy improves mood as well as insulin sensitivity in patients with a major depressive episode and type 2 diabetes.
  
  
  METHODS
  This study is a randomised, double-blind, parallel-arm trial in 98 participants with type 2 diabetes and a major depressive episode, according to DSM-IV criteria. We will assess whether light therapy improves depressive symptoms and insulin sensitivity, our primary outcome measures, and additionally investigate whether these effects are mediated by restoration of the circadian rhythmicity, as measured by sleep and hypothalamic-pituitary-adrenal axis activity. Participants will be randomly allocated to a bright white-yellowish light condition or dim green light condition. Participants will undergo light therapy for half an hour every morning for 4 weeks at home. At several time points, namely before the start of light therapy, during light therapy, after completion of 4 weeks of light therapy and after 4 weeks follow-up, several psychometrical, psychophysiological and glucometabolic measures will be performed.
  
  
  CONCLUSIONS
  If light therapy effectively improves mood and insulin sensitivity in type 2 diabetes patients with a major depressive episode, light therapy may be a valuable patient friendly addition to the currently available treatment strategies. Additionally, if our data support the role of restoration of circadian rhythmicity, such an observation may guide further development of chronobiological treatment strategies in this patient population.
  
  
  BACKGROUND
  The Netherlands Trial Register (NTR) NTR4942 . Registered 13 January 2015.
authors.affiliation: Department of Psychiatry, EMGO Institute for Health and Care Research, VU University Medical Centre and GGZ inGeest, Amsterdam, The Netherlands. a.brouwer1@vumc.nl.|VU University Medical Centre (ZH4A63), Postal Box 7057, 1007, MB, Amsterdam, The Netherlands. a.brouwer1@vumc.nl.
authors.forename: Annelies
authors.initials: A
authors.lastname: Brouwer
authors.affiliation: Diabetes Centre, VU University Medical Centre, Amsterdam, The Netherlands. d.vanraalte@vumc.nl.
authors.forename: Daniël H
authors.initials: DH
authors.lastname: van Raalte
authors.affiliation: Diabetes Centre, VU University Medical Centre, Amsterdam, The Netherlands.
authors.forename: Michaela
authors.initials: M
authors.lastname: Diamant
authors.affiliation: Department of Epidemiology and Biostatistics, EMGO Institute for Health and Care Research, VU University Medical Centre, Amsterdam, The Netherlands. f.rutters@vumc.nl.
authors.forename: Femke
authors.initials: F
authors.lastname: Rutters
authors.affiliation: Departments of Integrative Neurophysiology and Medical Psychology, Centre for Neurogenomics and Cognitive Research (CNCR), Neuroscience Campus Amsterdam, VU University and Medical Centre, Amsterdam, The Netherlands. e.vansomeren@nin.knaw.nl.
authors.forename: Eus J W
authors.initials: EJ
authors.lastname: van Someren
authors.affiliation: Department of Medical Psychology, VU University Medical Centre, Amsterdam, The Netherlands. fj.snoek@vumc.nl.
authors.forename: Frank J
authors.initials: FJ
authors.lastname: Snoek
authors.affiliation: Department of Psychiatry, EMGO Institute for Health and Care Research, VU University Medical Centre and GGZ inGeest, Amsterdam, The Netherlands. a.beekman@ggzingeest.nl.
authors.forename: Aartjan T F
authors.initials: AT
authors.lastname: Beekman
authors.affiliation: Department of Psychiatry, EMGO Institute for Health and Care Research, VU University Medical Centre and GGZ inGeest, Amsterdam, The Netherlands. ma.bremmer@vumc.nl.
authors.forename: Marijke A
authors.initials: MA
authors.lastname: Bremmer
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002940:Circadian Rhythm / Q000528:radiation effects; D003865:Major Depressive Disorder / Q000628:therapy*; D003924:Diabetes Mellitus, Type 2 / Q000523:psychology*; D004311:Double-Blind Method; D006801:Humans; D007030:Hypothalamo-Hypophyseal System / Q000528:radiation effects; D007333:Insulin Resistance / Q000528:radiation effects; D008875:Middle Aged; D019964:Mood Disorders / Q000628:therapy; D009426:Netherlands; D010789:Phototherapy / Q000379:methods*; D010913:Pituitary-Adrenal System / Q000528:radiation effects; D012893:Sleep Wake Disorders / Q000628:therapy; D016896:Treatment Outcome; D055815:Young Adult