Functional outcomes with bright light in monotherapy and combined with fluoxetine in patients with major depressive disorder: Results from the LIFE-D trial.

BACKGROUND: Bright light therapy has been shown to improve depressive symptoms in patients with nonseasonal major depressive disorder (MDD) but there are few studies examining functional outcomes. METHODS: We examined secondary functional outcomes in the 8-week randomized, placebo-sham-controlled LIFE-D trial comparing light therapy, fluoxetine, and the combination in patients with nonseasonal MDD. Functional assessments included the Sheehan Disability Scale (SDS) and, for employed participants, the Lam Employment Absence and Productivity Scale (LEAPS). Analysis of covariance (ANCOVA) was conducted with SDS and LEAPS change scores from baseline to week 8 as dependent variables, treatment modality (light, fluoxetine) as an independent variable, and baseline SDS and LEAPS scores as covariates. RESULTS: Of 122 randomized participants, SDS data were available for 105 and LEAPS data for 70. For the SDS, there were no interaction effects, but there was a significant small- to medium-sized main effect of light treatment on total SDS scores with corresponding significant effects in the Social Life and Family Life domains, but not in the Work/Study domain. There were no significant interaction or main effects with LEAPS scores. CONCLUSION: Light therapy significantly improved social and family life functioning in patients with MDD. However, work functioning was not significantly improved despite large effect sizes; these results were limited by low statistical power because of small sample sizes. Future studies should use longer treatment durations and be powered to detect clinically relevant differences in functional outcomes.

Quality of Life Impacts of Bright Light Treatment, Fluoxetine, and the Combination in Patients with Nonseasonal Major Depressive Disorder: A Randomized Clinical Trial.

OBJECTIVE: Bright light therapy is increasingly recommended (alone or in combination with antidepressant medication) to treat symptoms of nonseasonal major depressive disorder (MDD). However, little is known about its impacts on quality of life (QoL), a holistic, patient-valued outcome. METHODS: This study utilizes secondary outcome data from an 8-week randomized, controlled, double blind trial comparing light monotherapy (n = 32), fluoxetine monotherapy (n = 30), and the combination of these (n = 27) to placebo (n = 30). QoL was assessed using the Quality of Life Enjoyment and Satisfaction Questionnaire Short Form (Q-LES-Q-SF). Treatment-related differences in QoL improvements were assessed using a repeated measures analysis of variance. The influence of potential predictors of QoL (demographic variables and change in depressive symptoms) were investigated via hierarchical linear regression. RESULTS: Q-LES-Q-SF scores significantly improved across all treatment conditions; however, no significant differences were observed between treatment arms. QoL remained poor relative to community norms by the end of the trial period: Across conditions, 70.6% of participants had significantly impaired QoL at the 8-week assessment. Reduction in depressive scores was a significant predictor of improved QoL, with the final model accounting for 54% of variance in QoL change scores. CONCLUSION: The findings of this study emphasize that improvement in QoL and reduction in depressive symptoms in MDD, while related, cannot be taken to be synonymous. Adjunctive therapies may be required to address unmet QoL needs in patients with MDD receiving antidepressant or light therapies. Further research is required to explore additional predictors of QoL in order to better refine treatments for MDD.

Appetitive Symptoms Differentially Predict Treatment Response to Fluoxetine, Light, and Placebo in Nonseasonal Major Depression.

OBJECTIVE: We previously reported that morning bright light therapy is efficacious in adults with nonseasonal major depressive disorder (MDD), both on its own and in combination with fluoxetine. Given that appetitive symptoms predict response to bright light therapy in seasonal depression, we examined, in this secondary analysis, whether the same held true in these nonseasonal MDD patients. METHODS: Data were collected from October 7, 2009, to March 11, 2014. One hundred twenty-two patients who met DSM-IV-TR criteria for MDD without a seasonal pattern were randomly assigned to light monotherapy, fluoxetine, combination light and fluoxetine, or double-placebo (inactivated negative ion generator plus placebo pill). Multiple regression assessed the percentage change in Montgomery-Asberg Depression Rating Scale (MADRS) scores based on treatment condition, appetitive symptom score at baseline (sum of 4 items on the Structured Interview Guide for the Hamilton Depression Rating Scale, Seasonal Affective Disorders version), and the condition-by-appetitive score interaction. Sex was considered as a possible moderator of these effects. RESULTS: The overall regression model predicting treatment response was highly significant (P < .001), and the treatment condition-by-appetitive score interaction was a strong predictor of MADRS change scores (t = 2.65, P = .009). For individuals in the placebo group, more appetitive symptoms at baseline predicted less decrease in MADRS scores at 8 weeks (r = -0.37; large effect size). In contrast, for individuals in the active treatment groups, more appetitive symptoms at baseline predicted more of a decrease in depression scores at 8 weeks (fluoxetine group r = +0.23, medium effect size; light therapy group r = +0.11, small effect size; combination group r = +0.32, medium to large effect size). No moderation effect of sex was found. CONCLUSIONS: More severe appetitive symptoms at baseline predicted treatment response differentially across the 4 treatment groups. Contrary to prior findings in seasonal depression, this association was not robust for MDD patients receiving light therapy alone, although it was stronger in patients receiving fluoxetine with or without light. As the group sample sizes were modest, the current findings should be considered as preliminary only. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00958204.

Canadian Network for Mood and Anxiety Treatments (CANMAT) 2016 Clinical Guidelines for the Management of Adults with Major Depressive Disorder: Section 5. Complementary and Alternative Medicine Treatments.

(Reprinted by permission of SAGE Publications, Inc., from The Canadian Journal of Psychiatry 2016; 61:576-587. Copyright © 2016 by the Authors [https://doi.org/10.1177/0706743716660290]).

Canadian Network for Mood and Anxiety Treatments (CANMAT) 2016 Clinical Guidelines for the Management of Adults with Major Depressive Disorder: Section 5. Complementary and Alternative Medicine Treatments.

BACKGROUND: The Canadian Network for Mood and Anxiety Treatments (CANMAT) conducted a revision of the 2009 guidelines by updating the evidence and recommendations. The scope of the 2016 guidelines remains the management of major depressive disorder (MDD) in adults, with a target audience of psychiatrists and other mental health professionals. METHODS: Using the question-answer format, we conducted a systematic literature search focusing on systematic reviews and meta-analyses. Evidence was graded using CANMAT-defined criteria for level of evidence. Recommendations for lines of treatment were based on the quality of evidence and clinical expert consensus. "Complementary and Alternative Medicine Treatments" is the fifth of six sections of the 2016 guidelines. RESULTS: Evidence-informed responses were developed for 12 questions for 2 broad categories of complementary and alternative medicine (CAM) interventions: 1) physical and meditative treatments (light therapy, sleep deprivation, exercise, yoga, and acupuncture) and 2) natural health products (St. John's wort, omega-3 fatty acids; S-adenosyl-L-methionine [SAM-e], dehydroepiandrosterone, folate, Crocus sativus, and others). Recommendations were based on available data on efficacy, tolerability, and safety. CONCLUSIONS: For MDD of mild to moderate severity, exercise, light therapy, St. John's wort, omega-3 fatty acids, SAM-e, and yoga are recommended as first- or second-line treatments. Adjunctive exercise and adjunctive St. John's wort are second-line recommendations for moderate to severe MDD. Other physical treatments and natural health products have less evidence but may be considered as third-line treatments. CAM treatments are generally well tolerated. Caveats include methodological limitations of studies and paucity of data on long-term outcomes and drug interactions.

Efficacy of Bright Light Treatment, Fluoxetine, and the Combination in Patients With Nonseasonal Major Depressive Disorder: A Randomized Clinical Trial.

IMPORTANCE: Bright light therapy is an evidence-based treatment for seasonal depression, but there is limited evidence for its efficacy in nonseasonal major depressive disorder (MDD). OBJECTIVE: To determine the efficacy of light treatment, in monotherapy and in combination with fluoxetine hydrochloride, compared with a sham-placebo condition in adults with nonseasonal MDD. DESIGN, SETTING, AND PARTICIPANTS: Randomized, double-blind, placebo- and sham-controlled, 8-week trial in adults (aged 19-60 years) with MDD of at least moderate severity in outpatient psychiatry clinics in academic medical centers. Data were collected from October 7, 2009, to March 11, 2014. Analysis was based on modified intent to treat (randomized patients with ≥1 follow-up rating). INTERVENTIONS: Patients were randomly assigned to (1) light monotherapy (active 10,000-lux fluorescent white light box for 30 min/d in the early morning plus placebo pill); (2) antidepressant monotherapy (inactive negative ion generator for 30 min/d plus fluoxetine hydrochloride, 20 mg/d); (3) combination light and antidepressant; or (4) placebo (inactive negative ion generator plus placebo pill). MAIN OUTCOMES AND MEASURES: Change score on the Montgomery-Åsberg Depression Rating Scale (MADRS) from baseline to the 8-week end point. Secondary outcomes included response (≥50% reduction in MADRS score) and remission (MADRS score ≤10 at end point). RESULTS: A total of 122 patients were randomized (light monotherapy, 32; fluoxetine monotherapy, 31; combination therapy, 29; placebo, 30). The mean (SD) changes in MADRS score for the light, fluoxetine, combination, and placebo groups were 13.4 (7.5), 8.8 (9.9), 16.9 (9.2), and 6.5 (9.6), respectively. The combination (effect size [d] = 1.11; 95% CI, 0.54 to 1.64) and light monotherapy (d = 0.80; 95% CI, 0.28 to 1.31) were significantly superior to placebo in the MADRS change score, but fluoxetine monotherapy (d = 0.24; 95% CI, -0.27 to 0.74) was not superior to placebo. For the respective placebo, fluoxetine, light, and combination groups at the end point, response was achieved by 10 (33.3%), 9 (29.0%), 16 (50.0%), and 22 (75.9%) and remission was achieved by 9 (30.0%), 6 (19.4%), 14 (43.8%), and 17 (58.6%). Combination therapy was superior to placebo in MADRS response (ß = 1.70; df = 1; P = .005) and remission (ß = 1.33; df = 1; P = .02), with numbers needed to treat of 2.4 (95% CI, 1.6 to 5.8) and 3.5 (95% CI, 2.0 to 29.9), respectively. All treatments were generally well tolerated, with few significant differences in treatment-emergent adverse events. CONCLUSIONS AND RELEVANCE: Bright light treatment, both as monotherapy and in combination with fluoxetine, was efficacious and well tolerated in the treatment of adults with nonseasonal MDD. The combination treatment had the most consistent effects. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00958204.

Direct health care costs of treating seasonal affective disorder: a comparison of light therapy and fluoxetine.

Objective. To compare the direct mental health care costs between individuals with Seasonal Affective Disorder randomized to either fluoxetine or light therapy. Methods. Data from the CANSAD study was used. CANSAD was an 8-week multicentre double-blind study that randomized participants to receive either light therapy plus placebo capsules or placebo light therapy plus fluoxetine. Participants were aged 18-65 who met criteria for major depressive episodes with a seasonal (winter) pattern. Mental health care service use was collected for each subject for 4 weeks prior to the start of treatment and for 4 weeks prior to the end of treatment. All direct mental health care services costs were analysed, including inpatient and outpatient services, investigations, and medications. Results. The difference in mental health costs was significantly higher after treatment for the light therapy group compared to the medication group-a difference of $111.25 (z = -3.77, P = 0.000). However, when the amortized cost of the light box was taken into the account, the groups were switched with the fluoxetine group incurring greater direct care costs-a difference of $75.41 (z = -2.635, P = 0.008). Conclusion. The results suggest that individuals treated with medication had significantly less mental health care cost after-treatment compared to those treated with light therapy.

Barriers to achieving treatment goals: a focus on sleep disturbance and sexual dysfunction.

BACKGROUND: Patients who meet the criteria for a major depressive episode experience a constellation of symptoms, and different symptom configurations may reflect distinct underlying neurological disturbances. Similarly, the differing receptor profiles of the various antidepressants may explain relatively low remission rates and persistent symptoms even after remission. In particular, depressed patients frequently display altered circadian rhythms, sleep disturbances, and diurnal mood variation. Exploring treatments that can restore mood while having a positive impact on circadian rhythms and sleep would greatly improve the ability to treat this core features of depression. METHODS: The mechanisms of action of the various classes of antidepressants, their effects on sleep and issues beyond sleep, including sexual dysfunction, are explored, along with questions relating to adherence. RESULTS: Unfortunately, persistent sleep problems are among the most difficult-to-treat residual symptoms of depression. Many of the currently available antidepressants have adverse effects on circadian processes, including sleep, and may actually worsen sleep problems. Tolerability is also an enduring issue; SSRI and SNRI antidepressants are associated with central nervous sysytem and gastrointestinal effects, sexual side effects and suicidality. Improved drug tolerability would not only minimize distressing adverse effects, but would also improve adherence, thus maximizing the chances of successful treatment. CONCLUSIONS: The complexity of managing a major depressive episode is well illustrated by sleep disturbance and sexual dysfunction, two core symptoms of MDD that may also be caused or exacerbated by antidepressant therapy. Future antidepressants should alleviate symptoms without adversely affecting sleep or sexual function.

Neuropsychological functioning following craniopharyngioma removal.

The neuropsychological functioning of patients who had undergone surgical removal of craniopharyngiomas was compared to that of an endocrine control group composed of patients with nontumor hypopituitarism, an obese control group, and a normal control group. Neuropsychological assessments consisting of measures of intelligence, memory, attention, and executive functioning were carried out. The craniopharyngioma group had lower Performance IQ than did the normal control group, but their Performance IQ was comparable to that of the hypopituitarism and obese control groups. The craniopharyngioma patients did not differ in Verbal or Full Scale IQs from the remaining groups. There were no group differences on measures of verbal or nonverbal memory, ability to sustain attention, or executive functioning including measures of verbal or figural fluency, nonverbal problem solving, ability to copy a complex geometric figure, and visual motor and visual sequencing skills. The group mean scores on the measures of intelligence and neuropsychological abilities for the craniopharyngioma patients were in the low-average to average range. While craniopharyngioma patients can have significant morbidity including endocrine and visual deficits as well as obesity resulting from hyperphagia, neuropsychological deficits are not always present. Their neuropsychological outcome is more benign than some previous studies have suggested.

Quality of life as an outcome indicator in patients with seasonal affective disorder: results from the Can-SAD study.

BACKGROUND: Although a host of studies have now examined the relationship between quality of life (QoL) and non-seasonal depression, few have measured QoL in seasonal affective disorder (SAD). We report here on results from the Can-SAD trial, which assessed the impact of treatment with either antidepressant medication or light therapy upon QoL in patients diagnosed with SAD. METHOD: This Canadian double-blind, multicentre, randomized controlled trial included 96 patients who met strict diagnostic criteria for SAD. Eligible patients were randomized to 8 weeks of treatment with either: (1) 10000 lux light treatment and a placebo capsule or (2) 100 lux light treatment (placebo light) and 20 mg fluoxetine. QoL was measured with the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q) and the Medical Outcomes Study (MOS) Short-Form General Health Survey (SF-20) at baseline and 8 weeks. RESULTS: Both intervention groups showed significant improvement in QoL over time with no significant differences being detected by treatment condition. Q-LES-Q scores increased significantly in seven of eight domains, with the average scores rising from 48 x 0 (S.D.=10 x 7) at baseline to 69 x 1 (S.D.=15 x 6) at week 8. Treatment-related improvement in QoL was strongly associated with improvement in depression symptoms. DISCUSSION: Patients with SAD report markedly impaired QoL during the winter months. Treatment with light therapy or antidepressant medication is associated with equivalent marked improvement in perceived QoL. Studies of treatment interventions for SAD should routinely include broader indices of patient outcome, such as the assessment of psychosocial functioning or life quality.

Personality and seasonal affective disorder: results from the CAN-SAD study.

BACKGROUND: Personality factors have been implicated in seasonal affective disorder (SAD). The present study investigated the relationship between the five-factor model of personality (neuroticism, extraversion, openness, agreeableness, conscientiousness) and SAD. METHODS: Ninety-five patients with SAD completed personality measures before and after treatment in a clinical trial and during the summer months. The personality scores of the SAD patients were compared with a matched group of non-seasonal depressed patients and published normative data. Stability and change in personality scores with changes in mood state were assessed. Personality dimensions were evaluated as possible predictors of treatment outcome. RESULTS: SAD patients showed elevated openness scores relative to both non-seasonal depressed patients and norms. Their neuroticism scores were lower than non-seasonal depressed patients, but higher than norms. All personality dimensions showed large and highly significant test-retest correlations but several personality dimensions, particularly neuroticism and extraversion, also showed considerable change with changing mood state. None of the personality dimensions were significantly associated with treatment outcome. LIMITATIONS: Personality assessment relied on self-report. CONCLUSIONS: The personality profile of SAD patients differs from both non-seasonal depressed patients and norms. Elevated openness scores appear to be a unique feature of patients with SAD. Since mood state has a significant impact on personality scores, assessment of personality in SAD patients should ideally be conducted when they are in remission. Further investigation of the relationship between personality and SAD, especially the potential significance of elevated openness scores, is warranted.

The Can-SAD study: a randomized controlled trial of the effectiveness of light therapy and fluoxetine in patients with winter seasonal affective disorder.

OBJECTIVE: Light therapy and antidepressants have shown comparable efficacy in separate studies of seasonal affective disorder treatment, but few studies have directly compared the two treatments. This study compared the effectiveness of light therapy and an antidepressant within a single trial. METHOD: This double-blind, randomized, controlled trial was conducted in four Canadian centers over three winter seasons. Patients met DSM-IV criteria for major depressive disorder with a seasonal (winter) pattern and had scores > or = 23 on the 24-item Hamilton Depression Rating Scale. After a baseline observation week, eligible patients were randomly assigned to 8 weeks of double-blind treatment with either 1) 10,000-lux light treatment and a placebo capsule, or 2) 100-lux light treatment (placebo light) and fluoxetine, 20 mg/day. Light treatment was applied for 30 minutes/day in the morning with a fluorescent white-light box; placebo light boxes used neutral density filters. RESULTS: A total of 96 patients were randomly assigned to a treatment condition. Intent-to-treat analysis showed overall improvement with time, with no differences between treatments. There were also no differences between the light and fluoxetine treatment groups in clinical response rates (67% for each group) or remission rates (50% and 54%, respectively). Post hoc testing found that light-treated patients had greater improvement at 1 week but not at other time points. Fluoxetine was associated with greater treatment-emergent adverse events (agitation, sleep disturbance, palpitations), but both treatments were generally well-tolerated with no differences in overall number of adverse effects. CONCLUSIONS: Light treatment showed earlier response onset and lower rate of some adverse events relative to fluoxetine, but there were no other significant differences in outcome between light therapy and antidepressant medication. Although limited by lack of a double-placebo condition, this study supports the effectiveness and tolerability of both treatments for seasonal affective disorder and suggests that other clinical factors, including patient preference, should guide selection of first-line treatment.

O sweet spot where art thou? Light treatment of Seasonal Affective Disorder and the circadian time of sleep.

This study investigated Lewy's Phase Shift Hypothesis (PSH) for winter Seasonal Affective Disorder, which asserts that the phase angle difference (PAD) between circadian and sleep rhythms is critical in the mechanism of light's therapeutic action. Specifically, we sought to test whether a euthymic "sweet spot" could be identified at a PAD (between temperature minimum and wake time) of circa 3 h. After a baseline week, symptomatic SAD patients (N = 43) received 8 weeks of morning light treatment. Analyses were based on SIGH-SAD ratings made at baseline and posttreatment. Also estimated pre- and posttreatment were T(min) (calculated from an algorithm based on Morningness-Eveningness self-report scores), and the phase of the sleep-wake rhythm (as assessed by daily sleep logs). It was predicted that a quadratic relationship would exist between PAD and depression ratings at baseline and posttreatment, with lowest levels around PAD = 3 h. It was further predicted that shift towards PAD = 3 h with treatment would be associated with decreases in depression with treatment. Although trends were in the expected direction, none of the three predictions were supported. Findings are discussed in terms of the study's limitations and the experimental challenge of parsing independent and interacting contributions of sleep and circadian phase.

Therapeutic mechanism in seasonal affective disorder: do fluoxetine and light operate through advancing circadian phase?

In the context of Lewy's phase delay hypothesis, the present study tested whether effective treatment of winter Seasonal Affective Disorder (SAD) is mediated by advancing of circadian phase. Following a baseline week, 78 outpatients with SAD were randomized into 8 weeks of treatment with either fluoxetine and placebo light treatment or light treatment and placebo pill. Depression levels were measured on the Ham17+7 and the BDI-II, and circadian phase was estimated on the basis of daily sleep logs and self-reported morningness-eveningness. Among the 61 outpatients with complete data, both treatments were associated with significant antidepressant effect and phase advance. However, pre- and post-treatment comparisons found that the degree of symptom change did not correlate with the degree of phase change associated with treatment. The study therefore provides no evidence that circadian phase advance mediates the therapeutic mechanism in patients with SAD. Findings are discussed in terms of the limitations of the circadian measures employed.

Generic and health-related quality of life in patients with seasonal and nonseasonal depression.

Although a relatively large body of research has now accumulated concerning the relationship between quality of life (QoL) and nonseasonal depression, there is a dearth of information about QoL in seasonal affective disorder (SAD). The aim of this study was to compare perceived levels of broad ('generic') and health-related QoL in patients with seasonal and nonseasonal depression. Participants were 72 patients with SAD enrolled in an on-going multicentre study in Canada, and 72 patients with nonseasonal major depressive disorder (MDD) matched for severity of depression attending an outpatient psychiatric clinic in Vancouver, British Columbia. All participants completed two measures of QoL (the 20-item Medical Outcomes Study [MOS] Short-Form General Health Survey [SF-20] and the Quality of Life Enjoyment and Satisfaction Questionnaire [Q-LES-Q]) at baseline prior to treatment. The results of the study indicated that both generic and health-related QoL were compromised in patients with SAD compared with general population norms. For example, mean Q-LES-Q scores (range 0-100, where higher scores indicate better QoL) were 44%, compared with scores of 83% reported for the general population. Patients with nonseasonal depression showed significantly poorer functioning in several domains on the SF-20, but no significant differences in Q-LES-Q scores emerged. Perceived QoL is impaired in patients with SAD. Degree of impairment between seasonal and nonseasonal depressives is equivalent when assessed using the Q-LES-Q, but significant inter-group differences are apparent in SF-20 domain scores. Future research is required to determine whether perceived QoL is improved by treatment interventions for seasonal depression such as light therapy or antidepressant medication.

Development of an adjective checklist to measure five FACES of fatigue and sleepiness. Data from a national survey of insomniacs.

Development and initial validation of the FACES of fatigue and sleepiness adjective checklist. An initial item pool of 65 adjectives, descriptive of fatigue, sleepiness and related deprivation states, was developed and administered to 372 individuals referred by their family physicians for psychiatric investigation and treatment of severe insomnia. Participants attended one of six Canadian university-affiliated sleep clinics where they completed a psychiatric assessment and a 766-item questionnaire, including a number of standard indices of sleep-related behavior and symptoms, medical history, sleep hygiene, psychosocial well-being and psychopathology. Principal-components and item analyses were undertaken to refine the initial 65-item pool to a smaller 50-item set, consisting of five subscales: Fatigue, Anergy, Consciousness, Energized and Sleepiness. Coefficient alpha was calculated and indicated high internal consistency reliability for all subscales. Convergent and discriminant validity were also evaluated by calculating correlations between FACES subscales and a number of independent indices. The resulting five-scale FACES questionnaire appears to offer a promising self-report instrument for the measurement of fatigue and related subjective experiences.

Temporal coherence in ultradian sleep EEG rhythms in a never-depressed, high-risk cohort of female adolescents.

BACKGROUND: Previous work has indicated that low temporal coherence of ultradian sleep electroencephalographic rhythms is characteristic of depressed patients and of depressed women, in particular. It may also be evident in one quarter of those at high risk, based on a family history of depression. METHODS: The present study evaluated temporal coherence of sleep electroencephalographic rhythms in 41 adolescent girls with a maternal history of depression (high risk) and 40 healthy controls (low risk). The entire sample was followed clinically every 6 months for 2 years. RESULTS: Temporal coherence was significantly lower among the high-risk girls than in controls. Regression analyses predicted group from coherence values and correctly classified 70% of the high-risk group with a false-positive rate of 5% among controls. Moreover, 54% of the high-risk girls were identified with extreme low coherence. On clinical follow up, 14 girls showed depressive symptoms, 9 in the high-risk group (22.5%) and 5 controls (12.2%). Six met DSM-IV criteria for first-episode major depressive disorder, five high-risk and one control. Most importantly, 41% of those identified as having the most abnormal coherence values either showed symptoms of depression or met diagnostic criteria upon follow up. CONCLUSIONS: Low temporal coherence is evident in adolescent girls at high risk for depression. The more abnormal the coherence, the greater the risk of a first episode of major depressive disorder within 2 years of sleep study, approximately 10 times greater than in controls.