Phototherapy in nonseasonal depression

Previous reports have shown that bright light exposure may benefit patients with seasonal depression. In the present study, the possible therapeutic effect of bright light in nonseasonal major depressive disorder was examined. Forty-two depressed patients not receiving additional antidepressant medication were exposed to bright white light of 2500 lux or dim red light of 50 lux over one week for two hr daily in the morning. The change in depressive symptoms was assessed by rating scales (Hamilton Depression Rating Scale, CGI) and by self-rating scales (Depression Scale, Complaint List, Visual Analogue Scale). Consistent for all ratings, the decrease in depressive symptoms after bright white light was only slight and not different from dim red-light exposure. Contrary to the findings in seasonal affective disorder, phototherapy administered over one week for two hr daily is not effective in nonseasonal major depressive disorder.     

Adjunctive bright light in non-seasonal major depression: results from clinician-rated depression scales

OBJECTIVE: To investigate the use of bright light therapy as an adjunct treatment to sertraline in non-seasonal major depression. METHOD: In a randomised double-blind trial, 102 patients were treated for 5 weeks with either white bright light (10 000 lux, 1 h daily) or red dim light (50 lux, 30 min daily). All patients were treated with sertraline in a fixed dose of 50 mg daily. The clinician-rated depression scales used were the Hamilton Depression Rating Scale (HAM-D17), Hamilton six-item subscale (HAM-D6), Melancholia Scale (MES) and the seven 'atypical' items from the SIGH-SAD. RESULTS: One-hundred and two patients were included in the study. Analyses showed that the reduction in depression scores in the bright light group was statistically significantly larger than in the dim light group on all scales. The scale most sensitive at endpoint was the HAM-D(6), which includes the core symptoms of depression. CONCLUSION: The study results support the use of bright light as an adjunct treatment to antidepressants in non-seasonal depression.     

Sleep deprivation as a predictor of response to light therapy in major depression

Light therapy (LT) is regarded as the treatment of choice for seasonal affective disorder (SAD). In nonseasonal depression the results of light therapy are nonconclusive. Sleep deprivation (SD), however, is effective in 50-60% of the patients with major depression. The predictive value of Total Sleep Deprivation (TSD) for the treatment outcome of antidepressiva has been already examined. Purpose of the present study was to test whether light therapy is more beneficial in TSD responders than in TSD nonresponders. 40 inpatients with major depressive disorder completed one night of TSD. Twenty TSD responders and 20 TSD nonresponders were randomly assigned to 14 days of bright light therapy (2500 lux, 7-9 a.m.) or 14 days of dim light therapy (red light 50 lux, 7-9 a.m.). Manova with repeated measurements revealed a significant difference in the course of depression over the time between TSD responders and nonresponders, but no significant difference between bright and dim light. Questions of placebo effect, of SAD and of personality variables as predictors of response to SD and LT are being discussed.     

Bright light therapy decreases winter binge frequency in women with bulimia nervosa: a double-blind, placebo-controlled study

The study objective was to determine the effect of winter bright light therapy on binge and purge frequencies and depressive symptoms in subjects with bulimia nervosa. Thirty-four female bulimic outpatients were treated with either 10,000 lux bright white light or 50 lux dim red light (placebo control) during the winter months. In this double-blind study, the placebo group (n = 18) and the bright light group (n = 16) were matched for age, degree of seasonality (measured by the Seasonal Patterns Assessment Questionnaire [SPAQ]), and concurrent depression (measured by Structured Clinical Interview for DSM-IV [SCID]). Three weeks of baseline data collection were followed by 3 weeks of half-hour daily morning light treatment and 2 weeks of follow-up evaluation. There was a significant light-treatment by time interaction (Wilks' lambda = .81, F(2,28) = 3.31, P = .05). The mean binge frequency decreased significantly more from baseline to the end of treatment for the bright light group (F(1,29) = 6.41, P = .017) than for the placebo group. The level of depression (measured by daily Beck Depression Inventory [BDI] scores) did not significantly differ between the groups during any phase, and neither depression nor seasonality affected the response to light treatment. In this double-blind study, bulimic women who received 3 weeks of winter bright light treatment reported a reduced binge frequency between baseline and the active treatment period in comparison to subjects receiving dim red light.     

A controlled study of light therapy in women with late luteal phase dysphoric disorder.

Previous studies suggest that light therapy, as used to treat seasonal affective disorder, may be beneficial for pre-menstrual depressive disorders. We conducted a six-menstrual cycle randomized, double-blind, counter-balanced, crossover study of dim vs. bright light therapy in women with late luteal phase dysphoric disorder (LLPDD). Fourteen women who met DSM-III-R criteria for LLPDD completed two menstrual cycles of prospective baseline monitoring of pre-menstrual symptoms, followed by two cycles of each treatment. During the 2-week luteal phase of each treatment cycle, patients were randomized to receive 30 min of evening light therapy using: (1) 10000 lx cool-white fluorescent light (active condition); or (2) 500 lx red fluorescent light (placebo condition), administered by a light box at their homes. After two menstrual cycles of treatment, patients were immediately crossed over to the other condition for another two cycles. Outcome measures were assessed at the mid-follicular and luteal phases of each cycle. Results showed that the active bright white light condition significantly reduced depression and pre-menstrual tension scores during the symptomatic luteal phase, compared to baseline, while the placebo dim red light condition did not. These results suggest that bright light therapy is an effective treatment for LLPDD.     

Adjunctive bright light in non-seasonal major depression

OBJECTIVE: Bright light treatment is an established treatment for Seasonal Affective Disorder, but in non-seasonal depression research results have been contrasting. METHOD: This study was designed as a 5-week controlled, double-blind, parallel trial in out-patients with a diagnosis (DSM-IV) of non-seasonal major depression, randomized to either active treatment (white light, 10 000 lux, 1 h daily) or placebo treatment (red light, 50 lux, 30 min daily) and concomitant treatment with sertraline in both groups. RESULTS: One hundred and two patients were included in the study. Analyses showed that on all used scales the reduction in depression scores was larger in the bright light group than in the dim light group, and this reached statistical significance on all observer rating scales and on the SCL-90R self-assessment scale. The HAM-D6 was the most sensitive scale to measure improvement at endpoint. CONCLUSION: The study results support the use of bright light as an adjunct treatment to antidepressants in non-seasonal depression.     

Bright light augments antidepressant effects of medication and wake therapy

Inpatient studies have suggested that bright light therapy can be used to sustain the antidepressant effects of wake therapy (sleep deprivation). In an outpatient trial, a half night of home wake treatment was followed by 1 week of light treatment. All subjects had Major Depressive Disorders according to DSM-IV criteria and were receiving concomitant antidepressant medication. Subjects were randomly assigned to receive either 10,000 lux bright white light for 30 min between 6 and 9 AM or dim red (placebo) light at a comparable time. Seven subjects completed treatment with bright white light and six completed treatment with placebo. On the Hamilton Depression Rating Scale (HDRS17, SIGH-SAD-SR version), the group receiving bright light improved 27% in 1 week (P=0.002). The group receiving placebo did not improve, except for one outlier. The benefit of bright light was significant compared to placebo with removal of the outlier (P<0.025).     

The efficacy of light therapy in the treatment of mood disorders: a review and meta-analysis of the evidence

OBJECTIVE: The purpose of this study was to assess the evidence base for the efficacy of light therapy in treating mood disorders. METHOD: The authors systematically searched PubMed (January 1975 to July 2003) to identify randomized, controlled trials of light therapy for mood disorders that fulfilled predefined criteria. These articles were abstracted, and data were synthesized by disease and intervention category. RESULTS: Only 13% of the studies met the inclusion criteria. Meta-analyses revealed that a significant reduction in depression symptom severity was associated with bright light treatment (eight studies, having an effect size of 0.84 and 95% confidence interval [CI] of 0.60 to 1.08) and dawn simulation in seasonal affective disorder (five studies; effect size=0.73, 95% CI=0.37 to 1.08) and with bright light treatment in nonseasonal depression (three studies; effect size=0.53, 95% CI=0.18 to 0.89). Bright light as an adjunct to antidepressant pharmacotherapy for nonseasonal depression was not effective (five studies; effect size=-0.01, 95% CI=-0.36 to 0.34). CONCLUSIONS: Many reports of the efficacy of light therapy are not based on rigorous study designs. This analysis of randomized, controlled trials suggests that bright light treatment and dawn simulation for seasonal affective disorder and bright light for nonseasonal depression are efficacious, with effect sizes equivalent to those in most antidepressant pharmacotherapy trials. Adopting standard approaches to light therapy's specific issues (e.g., defining parameters of active versus placebo conditions) and incorporating rigorous designs (e.g., adequate group sizes, randomized assignment) are necessary to evaluate light therapy for mood disorders.     

Light treatment of seasonal affective disorder in Switzerland

Seasonal Affective Disorder (SAD) has been characterised by two or more depressive episodes in autumn or winter (with remission the following spring or summer), decreased energy, increased sleep, increased appetite, weight gain and carbohydrate craving. SAD patients were identified in a Swiss-German population; 22 participated in a light-therapy protocol (1 week bright white light 2,500 lux or dim yellow light 250 lux, from 06-08 h and 18-20 h). Both observer and self-ratings indicated a significant diminution of depressive symptoms with both lights. One week after withdrawal from yellow light, depression ratings relapsed to previous values; remission lasted longer after bright white light. Global VAS self-rating scales for "mood" and "well-being" however, and the Hamilton scale for atypical SAD symptoms, differentiated clearly between bright and dim light: only bright light showed an improvement that persisted after withdrawal. These results suggest that even though a placebo effect cannot be excluded, 4 h explicit light exposure/day may not be a negligible quantity. Light treatment promises to be a useful non-pharmacological intervention in certain forms of depressive illness.     

Adjunctive bright light in non-seasonal major depression: results from patient-reported symptom and well-being scales

OBJECTIVE: In this study, we tested the efficacy of bright light therapy as an adjunct to antidepressant treatment (sertraline) in patients with non-seasonal major depression. METHOD: In a randomized double-blind controlled trial, 102 patients were treated for 5 weeks with either white bright light (10.000 lx, 1 h/day) or red dim light (50 lx, 30 min/day). All patients received sertraline in a dosage of 50 mg daily. The self-assessment scales used were the Major Depression Inventory (MDI), the Psychological General Well-Being Scale (PGWB) and the Symptom Check List (SCL-90R). RESULTS: On all three questionnaires the score differences between baseline and endpoint were greatest in the bright light group. On the SCL-90R, the difference reached statistical significance. Results and effect sizes are compared with results from Danish national population studies applying PGWB and SCL-90R. CONCLUSION: The results advocate the use of bright light as an adjunct treatment of non-seasonal depression.     

Effect of bright white light on non-seasonal depressive disorder

In previous research, the therapeutic effect of bright white light for so so-called seasonal affective disorder was clearly confirmed. The aim of the present study was to evaluate possible beneficial effects of bright white light in non-seasonal depression. 30 patients fulfilling RDC-criteria for major depressive disorder were randomly assigned to a 7 day exposure from 7.20 to 9.20 a.m. The degree of illness was ascertained both objectively with observer rating scales (Hamilton Depression Scale, AMDP-system) and through self-rating scales (Complaint List and Depression Scale by von Zerssen). No difference was noted between bright light and dim light though a significant reduction of depressive symptomatology was observed for all patients during the treatment. These results were consistent for both observer rating and self-rating. In conclusion, bright white light has no superior effect as compared to dim light exposure in non-seasonal depression.     

Melatonin in light treatment of patients with seasonal and nonseasonal depression

Melatonin as a marker of circadian rhythm and the effect of bright light on melatonin were studied in 63 depressed patients, 42 with a seasonal pattern and 21 with a nonseasonal pattern. The patients were matched for age, time of treatment and severity of depression. Before light treatment, blood was sampled for melatonin and depression was clinically rated with the Comprehensive Psychopathological Rating Scale and Hamilton Depression Rating Scale. Two hours of light treatment, 350 cd/m², was given daily for 10 days 0600 to 0800 or 1800 to 2000. Of the 42 patients with seasonal depression, 26 were treated with morning light and, 16 with evening light. The melatonin amplitude was significantly decreased by light, and the melatonin phase position was advanced by morning light and delayed by evening light. All patients except for 3 in each group changed in the expected direction. Although the patients with seasonal pattern had a more favorable outcome than patients with nonseasonal pattern, there was no difference in therapeutic outcome related to the baseline melatonin phase position. The hypothesis that the short term clinical effects of light therapy either in the morning or evening are related to pretreatment melatonin levels or alteration of melatonin amplitude or phase position was not supported in the study. There was also no significant difference between the seasonal and nonseasonal patients related to the degree of light suppression of melatonin or the rebound effect of serum melatonin levels following bright light exposure between 2200 and 2300 before regular light treatment.     

Improvement in depression scores after 1 hour of light therapy treatment in patients with seasonal affective disorder

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.     

Bright light treatment of depression for older adults [ISRCTN55452501]

Background

The incidence of insomnia and depression in the elder population is significant. It is hoped that use of light treatment for this group could provide safe, economic, and effective rapid recovery.

Methods

In this home-based trial we treated depressed elderly subjects with bright white (8,500 Lux) and dim red (<10 Lux) light for one hour a day at three different times (morning, mid-wake and evening). A placebo response washout was used for the first week. Wake treatment was conducted prior to the initiation of treatment, to explore antidepressant response and the interaction with light treatment. Urine and saliva samples were collected during a 24-hour period both before and after treatment and assayed for aMT6s and melatonin respectively to observe any change in circadian timing. Subjects wore a wrist monitor to record light exposure and wrist activity. Daily log sheets and weekly mood (GDS) and physical symptom (SAFTEE) scales were administered. Each subject was given a SCID interview and each completed a mood questionnaire (SIGH-SAD-SR) before and after treatment. Also, Hamilton Depression Rating (SIGH-SAD version) interviews were conducted by a researcher who was blind to the treatment condition. A control group of healthy, age-matched, volunteers was studied for one day to obtain baseline data for comparison of actigraphy and hormone levels.

Results

Eighty-one volunteers, between 60 and 79 years old, completed the study. Both treatment and placebo groups experienced mood improvement. Average GDS scores improved 5 points, the Hamilton Depression Rating Scale (HDRS) 17 scores (extracted from the self-rated SIGH-SAD-SR) improved 6 points. There were no significant treatment effects or time-by-treatment interactions. No significant adverse reactions were observed in either treatment group. The assays of urine and saliva showed no significant differences between the treatment and placebo groups. The healthy control group was active earlier and slept earlier but received less light than the depressed group at baseline.

Conclusion

Antidepressant response to bright light treatment in this age group was not statistically superior to placebo. Both treatment and placebo groups experienced a clinically significant overall improvement of 16%.     

Effects of bright incandescent light on seasonal and nonseasonal major depressive disorder

Previous research has indicated that exposure to bright fluorescent light can benefit clinically depressed individuals. The present study, a 1- to 2-week open trial of bright (greater than or equal to 2,000 lux) incandescent light with seasonal (fall/winter) and nonseasonal depressives, produced a therapeutic effect on seasonal depression, as measured by three criteria for recovery: final score on the Hamilton Rating Scale for Depression (HRSD) less than 10; final HRSD score less than or equal to 50% of pretreatment HRSD score; no longer meets DSM-III criteria for major depressive disorder. Phototherapy was not effective in the nonseasonal patients, whose functioning was more impaired than that of the seasonal subjects even before the trial. No adverse effects were observed in any patient.     

The influence of phototherapy on serotonin and melatonin in non-seasonal depression

Circadian profiles of melatonin in serum and serotonin in blood were assessed before and after 7 days of artificial light treatment in 30 patients with non-seasonal depression and 12 healthy subjects. Patients and volunteers were allocated at random to either dim (50 lux) or bright light (2,500 lux) for 2 hours daily. The study has not been completed yet. Preliminary findings are presented here. Light treatment modifies marginally the circadian melatonin profiles of depressed patients and healthy subjects; however, it augments blood serotonin throughout the day. This increase is seen in all patients and healthy subjects after bright as well as dim light. These results suggest that the influence of light is more pronounced on serotonin than melatonin metabolism.     

Light treatment of mood disorders

In 1981, seven patients with nonseasonal depression were treated with bright white light in 1982, bright artificial light was used to treat a manic-depressive patient with a seasonal mood cycle. In the last 20 years, a plethora of studies have further defined the depressive populations, who are responsive to light treatment; the optimal timing, intensity, spectral frequency, and duration of treatment; its comparison with other pharmacological interventions; predictors of response; side-effect profiles; viable placebo-control conditions; alternative devices and forms of administration; potential mechanisms and anatomical pathways mediating light's physiological effects; and its application to other disorders and subsyndromaI states. These studies have been conducted across multiple countries with surprisingly consistent results. Further work is needed, as highlighted in this review, to clarify the specific mechanism of action in subtypes of depressive disorders and differential age and gender effects. Although the majority of work in this area is relatively new, it behooves the reader to remember that Solomon, almost 3000 years ago, wrote in Ecclesiastes: "Truly the light is sweet and a pleasant thing it is for the eyes to behold the sun" (11:7).     

High cortisol awakening response is associated with an impairment of the effect of bright light therapy

Objective: We investigated the predictive validity of the cortisol awakening response (CAR) in patients with non‐seasonal major depression. Method: Patients were treated with sertraline in combination with bright or dim light therapy for a 5‐week period. Saliva cortisol levels were measured in 63 patients, as an awakening profile, before medication and light therapy started. The CAR was calculated by using three time‐points: awakening and 20 and 60 min after awakening. Results: Patients with low CAR had a very substantial effect of bright light therapy compared with dim light therapy, whereas patients with a high CAR had no effect of bright light therapy compared with dim light therapy. Conclusion: High CAR was associated with an impairment of the effect of bright light therapy. This result raises the question of whether bright light acts through a mechanism different from that of antidepressants.     

Antidepressant effects of light in seasonal affective disorder

The authors treated winter depression in 13 patients with typical seasonal affective disorder by extending the length of winter days with bright and dim light in the morning and evening in a balanced-order crossover study. Bright light had a marked antidepressant effect, whereas the dim light did not. This response could not be attributed to sleep deprivation. Subsequent pilot studies indicated that bright evening light alone is probably also effective. Several patients were able to maintain the antidepressant response throughout the winter months by continuing daily light treatments.     

Diurnal variations of mood and sleep disturbances during phototherapy in major depressive disorder.

The influence of diurnal variations of mood (DVM) and sleep disturbances on treatment response was investigated in 42 patients with major depressive disorder (not SAD) under the treatment of either bright white light (2,500 lx) or dim red light (50 lx). We found only a slight influence in certain subscales of DVM and no influence of sleep disturbances. These results are discussed under a clinical point of view and with respect to phase shift theories of depressive disorders.