Article

Morning vs evening light treatment of patients with winter depression.

Department of Psychiatry, Oregon Health Sciences University, Portland 97201-3098, USA.
Archives of General Psychiatry (Impact Factor: 13.77). 11/1998; 55(10):890-6. DOI: 10.1001/archpsyc.55.10.890
Source: PubMed

ABSTRACT According to the phase-shift hypothesis for winter depression, morning light (which causes a circadian phase advance) should be more antidepressant than evening light (which causes a delay). Although no studies have shown evening light to be more antidepressant than morning light, investigations have shown either no difference or morning light to be superior. The present study assesses these light-exposure schedules in both crossover and parallel-group comparisons.
Fifty-one patients and 49 matched controls were studied for 6 weeks. After a prebaseline assessment and a light/dark and sleep/wake adaptation baseline week, subjects were exposed to bright light at either 6 to 8 AM or 7 to 9 PM for 2 weeks. After a week of withdrawal from light treatment, they were crossed over to the other light schedule. Dim-light melatonin onsets were obtained 7 times during the study to assess circadian phase position.
Morning light phase-advanced the dim-light melatonin onset and was more antidepressant than evening light, which phase-delayed it. These findings were statistically significant for both crossover and parallel-group comparisons. Dim-light melatonin onsets were generally delayed in the patients compared with the controls.
These results should help establish the importance of circadian (morning or evening) time of light exposure in the treatment of winter depression. We recommend that bright-light exposure be scheduled immediately on awakening in the treatment of most patients with seasonal affective disorder.

0 Bookmarks
 · 
124 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Resting frontal encephalographic (EEG) asymmetry, often conceptualized as a trait marker for depression, is influenced by occasion-specific factors, including time of year and the time of day of the recording session as demonstrated recently (Peterson and Harmon-Jones, 2009). The current study examined the influence of seasonal and chronological variables on resting frontal asymmetry, and also assessed whether different reference montages or surface transformations were equally susceptible to these influences. In a direct replication attempt, contrary to previous findings, no simple time of year by time of day interaction was found. Time awake at recording, however, was an important moderating variable of the relationship between photoperiod and time of day. EEG asymmetry scores based on current-source density (CSD) transformed data, however, appeared less vulnerable to these influences, providing further evidence to suggest that the CSD transform may be advantageous for examining stable trait estimates of frontal EEG asymmetry.
    Biological psychology 07/2012; 91(2):283-91. · 4.36 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The purpose of this study was to investigate possible rapid effects of light therapy on depressed mood in patients with seasonal affective disorder. Participants received 1 hour of bright light therapy and 1 hour of placebo dim red light in a randomized order crossover design. Depressed mood was measured at baseline and after each hour of light treatment using two self-report depression scales (Profile of Mood States-Depression-Dejection [POMS-D] subscale and the Beck Depression Inventory II [BDI-II]). When light effects were grouped for the two sessions, there was significantly greater reduction in self-report depression scores by -1.3 (p = 0.02) on the BDI-II and -1.2 (p = 0.02) on the POMS-D. A significant but modest improvement was detected after a single active light session. This is the first study, to our knowledge, to document an immediate improvement with light treatment using a placebo-controlled design with a clinical sample of depressed individuals.
    The Journal of nervous and mental disease 01/2012; 200(1):51-5. · 1.77 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: PURPOSE: Guidelines for the construction of critical care units require windows in room design to ensure a contribution of natural sunlight to ambient lighting. However, few studies have been published with evidence assessing this recommendation. We investigated the association of ambient light levels with clinical outcomes and sedative/analgesic/neuroleptic use in a medical intensive care unit (MICU). METHODS: This is a retrospective, observational study at a tertiary care facility with a 29-bed MICU. First/single MICU admissions between April 19, 2006, and June 30, 2009 (N = 3577), were analyzed with respect to clinical outcomes and sedation use according to MICU room orientation and corresponding light levels. RESULTS: Light levels were low but varied among the 4 room orientations. There were no significant differences in MICU mortality (north, 14.0%; east, 13.5%; west, 16.2%; south, 15.6%; P = .451), hospital mortality (20.8%, 20.9%, 22.2%, 22.3%; P = .796), 28-day intensive care unit-free days (17.6 ± 10.2, 18.0 ± 10.1, 17.7 ± 10.5, 17.2 ± 10.4; P = .555), 28-day ventilator-free days (16.3 ± 11.1, 16.5 ± 11.1, 15.5 ±11.5, 15.4 ± 11.4; P = .273). No clinically significant differences in intravenous sedative/analgesic use occurred across room orientations. CONCLUSIONS: Despite differing ambient light, room orientation was not associated with critical care outcomes or differences in sedative/analgesic/neuroleptic use. Current guidelines positing that windows alone are necessary or sufficient for MICU room light management may require further investigation and consideration.
    Journal of critical care 07/2012; · 2.13 Impact Factor

Full-text

View
1 Download