Light therapy for seasonal and nonseasonal depression: efficacy, protocol, safety, and side effects.

Clinical Chronobiology, New York State Psychiatric Institute, New York, NY 10032, USA.
CNS spectrums (Impact Factor: 1.3). 09/2005; 10(8):647-63; quiz 672.
Source: PubMed

ABSTRACT Bright light therapy for seasonal affective disorder (SAD) has been investigated and applied for over 20 years. Physicians and clinicians are increasingly confident that bright light therapy is a potent, specifically active, nonpharmaceutical treatment modality. Indeed, the domain of light treatment is moving beyond SAD, to nonseasonal depression (unipolar and bipolar), seasonal flare-ups of bulimia nervosa, circadian sleep phase disorders, and more. Light therapy is simple to deliver to outpatients and inpatients alike, although the optimum dosing of light and treatment time of day requires individual adjustment. The side-effect profile is favorable in comparison with medications, although the clinician must remain vigilant about emergent hypomania and autonomic hyperactivation, especially during the first few days of treatment. Importantly, light therapy provides a compatible adjunct to antidepressant medication, which can result in accelerated improvement and fewer residual symptoms.

Download full-text


Available from: Michael Terman, Jun 23, 2014
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Current research suggests that mood varies from season to season in some individuals, in conjunction with light-modulated alterations in chronobiologic indices such as melatonin and cortisol. The primary aim of this study was to evaluate the effects of seasonal variations in darkness on mood in depressed antepartum women, and to determine the relationship of seasonal mood variations to contemporaneous blood melatonin and cortisol measures; a secondary aim was to evaluate the influence of seasonal factors on measures of melancholic versus atypical depressive symptoms. We obtained measures of mood and overnight concentrations of plasma melatonin and serum cortisol in 19 depressed patients (DP) and 12 healthy control (HC) antepartum women, during on-going seasonal variations in daylight/darkness, in a cross-sectional design. Analyses of variance showed that in DP, but not HC, Hamilton Depression Rating Scale (HRSD) scores were significantly higher in women tested during seasonally longer versus shorter nights. This exacerbation of depressive symptoms occurred when the dim light melatonin onset, the melatonin synthesis offset, and the time of maximum cortisol secretion (acrophase) were phase-advanced (temporally shifted earlier), and melatonin quantity was reduced, in DP but not HC. Serum cortisol increased across gestational weeks in both the HC and DP groups, which did not differ significantly in cortisol concentration. Nevertheless, serum cortisol concentration correlated positively with HRSD score in DP but not HC; notably, HC showed neither significant mood changes nor altered melatonin and cortisol timing or quantity in association with seasonal variations. These findings suggest that depression severity during pregnancy may become elevated in association with seasonally related phase advances in melatonin and cortisol timing and reduced melatonin quantity that occur in DP, but not HC. Thus, women who experience antepartum depression may be more susceptible than their nondepressed counterparts to phase alterations in melatonin and cortisol timing during seasonally longer nights. Interventions that phase delay melatonin and/or cortisol timing-for example, increased exposure to bright evening light-might serve as an effective intervention for antepartum depressions whose severity is increased during seasonally longer nights.
    Chronobiology International 09/2013; DOI:10.3109/07420528.2013.808652 · 2.88 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In human beings, homeostatic and circadian sleep-wake regulatory processes are working together for the maintenance of sleep and wakefulness at appropriate times within the 24-hour light-dark cycle. The interaction between these processes also determines time-of-day modulations in sleepiness and alertness levels, and affects performance in a series of cognitive tasks. Besides, individuals differ in the synchronization of a great number of behaviors, ranging from preferred timing for sleep and wakefulness to habitual sleep duration or differences in sleep depth and sleep structure. Genetic factors have been shown to contribute substantially to inter-individual differences in most of these variables. Trait-like variability has also been suggested in the cerebral bases underlying cognitive effort under adverse circadian phase and sleep deprivation. The field of human sleep and chronobiology research has been shown suitable for translational research such that a multitude of therapeutic tools have been derived, which start to be recognized in sleep medicine and psychiatry. Regarding the presence of prominent inter-individual variability in sleep-wake behaviors and its impact on cognition and subjective wellbeing, individually tailored schemes might be more accurate, also for the prediction of treatment efficiency at the clinical level.
    Journal of Cognitive and Behavioral Psychotherapies 07/2013; 13(1a):133-170. · 0.30 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Disruption of the circadian rhythm is detrimental to human well being, with consequences ranging from lower productivity, sleep disorder, to more serious health problems. Accurate estimation of circadian argument is critical to the assessment and treatment of circadian disruption. Circadian argument estimate is also essential for light-based circadian entrainment. Direct measurements of circadian rhythm markers such as dim light melatonin onset are inconvenient and acquired at best at low rate. Wearable continuous measurement such as actigraph is convenient but is masked by many other factors. In this paper, we present a new circadian rhythm estimation scheme based on a type of frequency tracker, called adaptive notch filter (ANF) which is commonly used in signal processing. ANF is designed to track the gain and phase of a single sinusoid from noisy data. We extend the classic ANF to multiple harmonics needed in circadian rhythm tracking. The local stability and high order harmonics robustness are analyzed. The highly noisy indirect measurements result in unreliable amplitude estimate, but the phase estimate is generally quite robust. We use this phase estimate combined with the light input to construct a black-box linear time varying (LPV) system description, parameterized by the phase estimate. The LPV model predicts the circadian rhythm response to light inputs and can be used for the design of light-based feedback control. The proposed modeling and control method is applied to three different models of circadian rhythm: Kronauer's human circadian model, Leloup's Drosophila circadian model and Neurospora circadian model. Simulation shows that our approach can generate reliable circadian argument estimation and effective gain-scheduled control of the circadian rhythm without any knowledge of the underlying model. The ability to generate circadian estimate, model, and control based only on input/output data opens up the tantalizing possibility of personalized ci- cadian rhythm estimator and light therapy.
    American Control Conference (ACC), 2013; 06/2013