'Light therapy' is established worldwide as the treatment of choice for seasonal affective disorder. It is also successfuly used in nonseasonal depression, as well as for many other psychiatric and neurologic illnesses, and in sleep medicine. 'Wake therapy' is the fastest antidepressant known. Imaging studies show that both methods share neurobiolo

The International Society for Bipolar Disorders (ISBD) Chronobiology and Chronotherapy Task Force conducted a comprehensive review to deliver concise evidence-based recommendations on the use of bright light therapy (BLT) for bipolar disorder (BD). Adjunctive BLT is likely an efficacious acute treatment for bipolar depression as implicated by higher quality evidence. The position of maintenance BLT for relapse prevention awaits further investigation. Protocols of effective BLT in BD are similar to parameters indicated for treatment of seasonal and non-seasonal major depressive disorder. Anti-manic prophylaxis (especially for BD-I) and clinical monitoring are recommended with initiation of and ongoing light treatment. Administer BLT daily, preferably in the morning or at mid-day. If mornings are prohibitive, then mid-day exposure, implemented to avoid excessively early wake times, is an acceptable alternative. Informed by the literature, target 30 min/day of BLT exposure. Patients wary of emergent hypomania or partial responders, can initiate 15 min/day and increase by 15 min each week to full response (or 30-60 min/day by the fourth week). Consider patient centred outcome assessments to evaluate mood response, safety and side effects. Clinical improvement is typically observed within 1-2 weeks, with response/remission expected by 4-6 weeks. Integration of BLT with other chronotherapeutic strategies may enhance long-term efficacy.

Light therapy has become established as an evidence-based treatment for Seasonal Affective Disorder. Light impacts the timing and stability of circadian rhythms as expressed in sleep, mood, alertness, and cognition. Forty years of clinical trials and open treatment have led to guidelines for patient selection, using light alone or in combination with antidepressants (or lithium for bipolar depression). Mood and sleep disturbances can also respond to adjunct light therapy in a broader set of psychiatric, neurologic and medical illnesses. We specify criteria for choice of treatment devices: optimum dose (10,000 lux), spectrum (white light), exposure duration (30-60 minutes) and timing (early morning). Protocol adjustment requires continual monitoring with attention to rate of improvement and management of potential side effects.

Light is the most powerful "zeitgeber" signal to synchronize circadian sleep-wake cycles. In dementia, these rhythms are often fragmented - probably due to loss of neuronal function of the suprachiasmatic nuclei (the biological "master clock" in the brain) and/or weakness of external zeitgebers. We investigated the effects of a prototype dawn-dusk simulator (DDS) on circadian rest-activity cycles, sleep, mood and well-being in a balanced crossover design during fall and winter in 20 institutionalized patients with dementia (86 +/- 6 y, 17 f). All participants had one baseline week followed by exposure to individually timed DDS over their beds for 7-8 weeks. They spent 8 weeks without DDS as a control. Mood, self-reliant daily activity, social behavior, agitation, and quality of life were assessed by standardized questionnaires and visual analogue scales, regularly rated by trained caregivers. Circadian and sleep characteristics of their rest-activity cycles were analyzed by actimetry over 17 weeks. DDS exposure led to significantly better mood in the morning hours after waking. The effects were most pronounced in the second 4 weeks with DDS, indicating that positive effects emerged gradually. Differences in circadian rest-activity cycles and sleep were mainly age-dependent. We found statistically significant correlations between measures of higher quality of life and better mood, greater alertness and circadian rhythm stability. We conclude that continuous, long-term application of dawn-dusk simulation at the sleep-wake transitions appears to increase external zeitgeber strength in institutionalized patients with dementia. The DDS may provide an effective, non-invasive tool to improve mood and ameliorate patients' quality of life.

Light treatment stands as the first active clinical intervention for major depression, with an underpinning in basic lab research on the circadian timing system and seasonal physiological changes in animals. By contrast, pharmaceutical treatments were discovered as side effects of drugs targeted at other medical disorders. The first randomized, controlled clinical trial showed that winter depression (seasonal affective disorder) could remit by truncating long winter nights with bright artificial light in late evening and early morning. Morning light proved most effective, which implicated a change in circadian timing. Seasonality, however, is not essential for the light effect: The much larger cohort of patients with non-seasonal depression also responds to morning light. Bipolar depression can remit as quickly as after a single night awake, but with high risk of relapse after sleep the next night. By adding daily morning light treatment after the night awake, the remission is sustained. Circadian rhythm sleep disorders, especially with sleep onset insomnia, can be normalized by timed light treatment, avoiding recourse to hypnotic drugs. New applications of light treatment with promising initial data include attention deficit hyperactivity disorder, fibromyalgia and other pain disorders, and symptoms of Parkinson's disease and dementia.

Back to table of contents Previous article Next article Letters to the EditorFull AccessLight Therapy and Risk of Hypomania, Mania, or Mixed State Emergence: Response to Benedetti et al.Dorothy K. Sit, M.D., Michael Terman, Ph.D., Katherine L. Wisner, M.D., M.S.Dorothy K. Sit, M.D., Michael Terman, Ph.D., Katherine L. Wisner, M.D., M.S.Published Online:1 Sep 2018https://doi.org/10.1176/appi.ajp.2018.18020231rAboutSectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail To the Editor: We chose midday light for our randomized controlled trial of patients with bipolar disorder because of the findings from our pilot study (1). Three of our first four women with depression treated with antimanic drugs rapidly developed mixed states, which necessitated discontinuation of morning light therapy. However, we have recommended morning light therapy for patients who do not respond to 45–60 minutes of midday light therapy. The interpretation that morning light therapy is contraindicated is not consistent with our publications (1, 2).Morning light therapy can elicit abrupt, large circadian rhythm phase advances that may precipitate bipolar switching, as has been described after eastward jet travel. Midday light therapy is far less likely to induce similar phase shifts and is a conservative initial treatment. The gradual emergence of group differences in our controlled study of midday light therapy (2) contrasts with the rapid improvement often seen with morning light therapy, which may reflect the relative circadian rhythm potency associated with the timing of light therapy.The claim of “proven efficacy and safety” of early morning bright light treatment for bipolar depression is overstated. Many of the publications on morning light therapy and bipolar disorder in Dr. Benedetti’s review (3) included studies of seasonal depression and patients with both unipolar and bipolar disorder. Other studies were constrained by open trial design, lack of a comparator group, brief duration, inclusion of antidepressants with adjunctive light therapy, and light therapy combined with sleep deprivation. Assessing hypomanic or manic symptoms with a valid measure is necessary to quantify the rate of their emergence (4). Only 12 of 43 studies (3) included the administration of a mania scale, which will bias the results toward underestimating the occurrence of mixed states and hypomania.With due respect to our colleagues, the extensive list of authors who “have used [morning light therapy] in everyday clinical practice” (as have we) cannot supplant controlled clinical trial data. In his comprehensive survey (3), Dr. Benedetti reported that morning light therapy has been compared with placebo for bipolar disorder in only three studies. Using the Young Mania Rating Scale in two of the studies, symptoms were absent or rare, while the third study lacked a standard mania measure. With midday light therapy, we did not observe any mixed states, hypomania or mania, or significant differences in scores on the mania rating scale. Direct comparisons of midday and morning light therapy in a randomized controlled trial, with attention to gender-specific rates and predictors of hypomania or mania and mixed state emergence, would be a valuable contribution.From the Department of Psychiatry and Behavioral Sciences, Feinberg School of Medicine, Northwestern University, Chicago; and the Department of Psychiatry, Columbia University and New York State Psychiatric Institute, New York.Address correspondence to Dr. Sit ([email protected]).The authors’ disclosures accompany the original article.References1 Sit D, Wisner KL, Hanusa BH, et al.: Light therapy for bipolar disorder: a case series in women. Bipolar Disord 2007; 9:918–927Crossref, Medline, Google Scholar2 Sit DK, McGowan J, Wiltrout C, et al.: Adjunctive bright light therapy for bipolar depression: a randomized double-blind placebo-controlled trial. Am J Psychiatry 2018; 175:131–139Link, Google Scholar3 Benedetti F: Rate of switch from bipolar depression into mania after morning light therapy: a historical review. Psychiatry Res 2018; 261:351–356Crossref, Medline, Google Scholar4 Angst J, Adolfsson R, Benazzi F, et al.: The HCL-32: towards a self-assessment tool for hypomanic symptoms in outpatients. J Affect Disord 2005; 88:217–233Crossref, Medline, Google Scholar FiguresReferencesCited byDetailsCited byCarbon monoxide: a critical physiological regulator sensitive to light9 March 2020 | Translational Psychiatry, Vol. 10, No. 1 Volume 175Issue 9 September 01, 2018Pages 906-906 Metrics KeywordsMood Disorders-BipolarAntidepressantsBipolar DisordersNon-Seasonal DepressionLight TherapyClinical TrialNon-PharmacologicalNovel InterventionPDF download History Accepted 28 March 2018 Published online 1 September 2018 Published in print 1 September 2018

OBJECTIVE Patients with bipolar disorder have recurrent major depression, residual mood symptoms, and limited treatment options. Building on promising pilot data, the authors conducted a 6-week randomized double-blind placebo-controlled trial to investigate the efficacy of adjunctive bright light therapy at midday for bipolar depression. The aims were to determine remission rate, depression symptom level, and rate of mood polarity switch, as well as to explore sleep quality. METHOD The study enrolled depressed adults with bipolar I or II disorder who were receiving stable dosages of antimanic medication (excluding patients with hypomania or mania, mixed symptoms, or rapid cycling). Patients were randomly assigned to treatment with either 7,000-lux bright white light or 50-lux dim red placebo light (N=23 for each group). Symptoms were assessed weekly with the Structured Interview Guide for the Hamilton Depression Scale With Atypical Depression Supplement (SIGH-ADS), the Mania Rating Scale, and the Pittsburgh Sleep Quality Index. Remission was defined as having a SIGH-ADS score of 8 or less. RESULTS At baseline, both groups had moderate depression and no hypomanic or manic symptoms. Compared with the placebo light group, the group treated with bright white light experienced a significantly higher remission rate (68.2% compared with 22.2%; adjusted odds ratio=12.6) at weeks 4-6 and significantly lower depression scores (9.2 [SD=6.6] compared with 14.9 [SD=9.2]; adjusted β=-5.91) at the endpoint visit. No mood polarity switches were observed. Sleep quality improved in both groups and did not differ significantly between them. CONCLUSIONS The data from this study provide robust evidence that supports the efficacy of midday bright light therapy for bipolar depression.

Patients with Bipolar Disorders (BD) have recurrent major depression, residual mood symptoms, and limited treatment options. We conducted a 6-week, double-blind, parallel, placebo-controlled trial to investigate the efficacy of midday bright light therapy for bipolar depression. The aims were to determine remission rates, depression severity, and the rate of mood polarity switch in patients randomized to 7000-lux bright white or 50-lux dim red light.

ObjectivesThe discovery of the blue lightsensitive retinal photoreceptor responsible for signaling daytime to the brain suggested that light to the circadian system could be inhibited by using blue‐blocking orange tinted glasses. Blue‐blocking (BB) glasses are a potential treatment option for bipolar mania. We examined the effectiveness of BB glasses in hospitalized patients with bipolar disorder in a manic state.MethodsIn a single‐blinded, randomized, placebo‐controlled trial (RCT), eligible patients (with bipolar mania; age 18–70 years) were recruited from five clinics in Norway. Patients were assigned to BB glasses or placebo (clear glasses) from 6 p.m. to 8 a.m. for 7 days, in addition to treatment as usual. Symptoms were assessed daily by use of the Young Mania Rating Scale (YMRS). Motor activity was assessed by actigraphy, and compared to data from a healthy control group. Wearing glasses for one evening/night qualified for inclusion in the intention‐to‐treat analysis.ResultsFrom February 2012 to February 2015, 32 patients were enrolled. Eight patients dropped out and one was excluded, resulting in 12 patients in the BB group and 11 patients in the placebo group. The mean decline in YMRS score was 14.1 [95% confidence interval (CI): 9.7–18.5] in the BB group, and 1.7 (95% CI: −4.0 to 7.4) in the placebo group, yielding an effect size of 1.86 (Cohen's d). In the BB group, one patient reported headache and two patients experienced easily reversible depressive symptoms.ConclusionsThis RCT shows that BB glasses are effective and feasible as add‐on treatment for bipolar mania.