Temporal relation between sleep and mood in patients with bipolar disorder

Modeling BAS Dysregulation in Bipolar Disorder

Time series analysis is a technique that can be used to analyze the data from a single subject and has great potential to investigate clinically relevant processes like affect regulation. This article uses time series models to investigate the assumed dysregulation of affect that is associated with bipolar disorder. By formulating a number of alternative models that capture different kinds of theoretically predicted dysregulation, and by comparing these in both bipolar patients and controls, we aim to illustrate the heuristic potential this method of analysis has for clinical psychology. We argue that, not only can time series analysis elucidate specific maladaptive dynamics associated with psychopathology, it may also be clinically applied in symptom monitoring and the evaluation of therapeutic interventions.

Polysomnographic characteristics of bipolar hypomanic patients: Comparison with unipolar depressed patients

BACKGROUND

Sleep profile in bipolar disorder has received little attention in comparison to sleep studies in major depressive disorders. Specific sleep abnormalities especially in REM sleep parameters have been detected in depression. The current study aimed at investigating whether bipolar disorder shares the same polysomnographic (PSG) changes or not.

METHODS

All night polysomnographic assessments were made for 20 patients diagnosed to have hypomania, in addition to 20 patients with major depression and 20 healthy matched controls. All participants were examined using Standardized Sleep Questionnaire, SCID-I for psychiatric diagnosis, based on DSM-IV criteria, YMRS (for hypomanic patients), HAMD (for major depression patients), and all-night polysomnography (for all subjects).

RESULTS

The two patient groups differed significantly from controls in their sleep profile, especially regarding sleep continuity measures, Short REML (Rapid Eye Movement Latency), with increased REMD (Rapid Eye Movement sleep density). High similarity was found in EEG sleep profile of the two patient groups, though the changes were more robust in patients with depression

LIMITATIONS

A relatively small sample size, the absence of follow up assessment, lack of consideration of other variables like body mass index, nicotine and caffeine intake.

CONCLUSION

Similarity in EEG sleep profile between Bipolar disorder patients and patients with major depression suggests a common biological origin for both conditions, with the difference being "quantitative" rather than "qualitative". This quantitative difference in sleep efficiency and SWS (Slow wave sleep), being higher in hypomania, might explain the rather "refreshing" nature of sleep in hypomanic patients, compared to depression.

Sleep, residual mood symptoms, and time to relapse in recovered patients with bipolar disorder

BACKGROUND

Sleep disturbance in bipolar disorder (BD) is common during and between mood episodes. In recovered (euthymic at least two months) BD patients, we assessed sleep compared to controls and its relationships with residual mood symptoms and mood episode recurrence.

METHOD

Recovered Stanford University BD Clinic patients diagnosed with the Systematic Treatment Enhancement Program for BD (STEP-BD) Affective Disorders Evaluation and monitored with the STEP-BD Clinical Monitoring Form (CMF) for >1 year and healthy controls completed the Pittsburgh Sleep Quality Index (PSQI). PSQI parameters were compared in BD patients versus controls, and the most robustly differentiating PSQI parameter was assessed in relationship to residual mood symptoms, and time to mood episode recurrence in BD patients.

RESULTS

Eighty nine recovered BD patients compared to 56 healthy controls had significantly worse PSQI global score, more sleep medication use, longer sleep latency, and worse daytime dysfunction. PSQI global score had the greatest BD patient versus control effect size, and among BD patients, correlated significantly with residual mood symptoms and predicted earlier mood episode recurrence, even after covarying for residual mood symptoms.

LIMITATIONS

Use of subjective (PSQI) rather objective (polysomnography) sleep metric. Statistical power limited by small sample size. Potential psychotropic medication confound. Northern California tertiary BD clinic referral sample.

CONCLUSION

Further research is needed to confirm that in recovered BD patients, poor sleep quality correlates with residual mood symptoms, and independently predicts mood episode recurrence. If confirmed, these observations suggest potential mood benefit for focusing on sleep quality in interventions for recovered BD patients.

Abnormalities in sleep patterns in individuals at risk for psychosis and bipolar disorder

AIM

To compare patterns of sleep and the presence of sleep disturbances in individuals in at-risk mental states (ARMS) for psychosis and bipolar disorder (BD) with a healthy control (HC) group.

METHODS

This was a comparative study involving 20 individuals in ARMS for psychosis or BD, according to the Comprehensive Assessment of At-Risk Mental States, and 20 age- and sex-matched healthy controls. Quality of sleep in the previous month was assessed using the Pittsburgh Sleep Quality Index, diurnal somnolence was evaluated using The Epworth Sleepiness Scale, and chronotype was determined using the Questionnaire of Morningness/Eveningness (QME). All of the participants underwent polysomnography (PSG) during the entire night for two consecutive nights. The first night aimed to adapt the subject to the environment, and only the data from the second night were used for the analysis.

RESULTS

Compared with the HC group, individuals in the ARMS group reported significantly worse sleep quality, as measured by the Pittsburgh Sleep Quality Index. Both groups had scores consistent with daytime sleepiness on the Epworth Sleepiness Scale, and there were no differences with regard to chronotype between the groups, with a predominance of the indifferent type in both groups. In the PSG assessment, we observed increased Sleep Latency (SL) and increased Rapid Eye Movement Sleep Onset Latency (REMOL) in the ARMS group, compared to the HC group.

CONCLUSION

The results of this study indicated that sleep abnormalities could be found early in the course of mental diseases, even in at-risk stages, and support the further investigation of their predictive value in the transition to psychosis and BD.

The bipolarity of light and dark: A review on Bipolar Disorder and circadian cycles

BACKGROUND

Bipolar Disorder is characterized by episodes running the full mood spectrum, from mania to depression. Between mood episodes, residual symptoms remain, as sleep alterations, circadian cycle disturbances, emotional deregulation, cognitive impairment and increased risk for comorbidities. The present review intends to reflect about the most recent and relevant information concerning the biunivocal relation between bipolar disorder and circadian cycles.

METHODS

It was conducted a literature search on PubMed database using the search terms "bipolar", "circadian", "melatonin", "cortisol", "body temperature", "Clock gene", "Bmal1 gene", "Per gene", "Cry gene", "GSK3β", "chronotype", "light therapy", "dark therapy", "sleep deprivation", "lithum" and "agomelatine". Search results were manually reviewed, and pertinent studies were selected for inclusion as appropriate.

RESULTS

Several studies support the relationship between bipolar disorder and circadian cycles, discussing alterations in melatonin, body temperature and cortisol rhythms; disruption of sleep/wake cycle; variations of clock genes; and chronotype. Some therapeutics for bipolar disorder directed to the circadian cycles disturbances are also discussed, including lithium carbonate, agomelatine, light therapy, dark therapy, sleep deprivation and interpersonal and social rhythm therapy.

LIMITATIONS

This review provides a summary of an extensive research for the relevant literature on this theme, not a patient-wise meta-analysis.

CONCLUSIONS

In the future, it is essential to achieve a better understanding of the relation between bipolar disorder and the circadian system. It is required to establish new treatment protocols, combining psychotherapy, therapies targeting the circadian rhythms and the latest drugs, in order to reduce the risk of relapse and improve affective behaviour.

Disturbed sleep as risk factor for the subsequent onset of bipolar disorder--Data from a 10-year prospective-longitudinal study among adolescents and young adults

There is ample data suggesting that individuals with bipolar disorder more frequently suffer from disturbed sleep even when euthymic. Since sleep is a process that is crucial for affective homeostasis, disturbed sleep in healthy individuals may be a risk factor for the subsequent onset of bipolar disorder. Utilizing data from a large cohort of adolescents and young adults, this study tests the hypothesis that disturbed sleep constitutes a risk factor for the later onset of bipolar disorder. A representative community sample of N = 3021 adolescents and young adults (baseline age 14-24) was assessed using the standardized Composite International Diagnostic Interview and followed-up prospectively up to 3 times over up to 10 years. Disturbed sleep at baseline was quantified utilizing the corresponding items from the self-report inventory SCL-90-R. The compound value (insomnia-score) as an ordinal parameter for the severity of sleep disturbances was used to assess associations with the incidence of bipolar disorder among participants free of major mental disorder at baseline (N = 1943) using odds ratios (OR) from logistic regressions. Analyses were adjusted for age, gender, parental mood disorder and lifetime alcohol or cannabis dependence. Poor sleep quality significantly increased the risk for the subsequent development of bipolar disorder (OR = 1.75; p = 0.001). Regarding individual sleep items, trouble falling asleep and early morning awakening were predictive for the subsequent onset of bipolar disorder. Disturbed sleep in persons otherwise free of major mental disorders appears to confer an increased risk for the subsequent onset of bipolar disorder.

Comparison of precipitating factors for mania and partial seizures: Indicative of shared pathophysiology?

OBJECTIVES

Mania in bipolar disorder (BD) and partial (focal) seizures (PS) arising from the temporal lobes, have a number of similarities. Typically, a chronic course of the disorders is punctuated by acute illness episodes. Common features of episodes may include sensory, perceptual, cognitive and affective changes. Both respond to anticonvulsant treatment. Common mechanisms imputed include neurotransmitters and kindling processes. Further investigation may improve understanding of the occurrence of both mania and PS, casting light on the relevance of temporal lobe mediated processes and pathology. One avenue of investigation is to compare aetiological factors and determine the extent of overlap which may indicate shared brain localization or pathophysiology. Aetiology includes predisposing, precipitating or perpetuating factors. This paper examines the literature on precipitating factors of mania, first or subsequent episode, and of PS in diagnosed epilepsy, which is the second or subsequent seizure, to identify the extent and nature of their overlap.

METHOD

Narrative review based on a literature search of PubMed and Google Scholar.

RESULTS

Precipitating factors for both mania and PS were stress, sleep deprivation, antidepressant medication and, tentatively, emotion. For mania alone, goal-attainment events, spring and summer season, postpartum, and drugs include steroids and stimulants. For PS alone, winter season, menstruation and specific triggers in complex reflex epilepsies. Those not substantiated include lunar phase and menopause. A wide range of chemicals may provoke isolated seizures but by definition epilepsy requires at least two seizures.

CONCLUSIONS

The overlap of precipitating factors in mania and PS imply that common brain processes may contribute to both, consistent with findings from neuroscience research.

Chronobiology of bipolar disorder: therapeutic implication

Multiple lines of evidence suggest that psychopathological symptoms of bipolar disorder arise in part from a malfunction of the circadian system, linking the disease with an abnormal internal timing. Alterations in circadian rhythms and sleep are core elements in the disorders, characterizing both mania and depression and having recently been shown during euthymia. Several human genetic studies have implicated specific genes that make up the genesis of circadian rhythms in the manifestation of mood disorders with polymorphisms in molecular clock genes not only showing an association with the disorder but having also been linked to its phenotypic particularities. Many medications used to treat the disorder, such as antidepressant and mood stabilizers, affect the circadian clock. Finally, circadian rhythms and sleep researches have been the starting point of the developing of chronobiological therapies. These interventions are safe, rapid and effective and they should be considered first-line strategies for bipolar depression.

Effects of CLOCK gene variants and early stress on hopelessness and suicide in bipolar depression

BACKGROUND

Patients with mood disorders show a high dependence of behavior on the molecular characteristics of the biological clock. CLOCK rs1801260 gene polymorphism influences circadian behavior in bipolar disorder (BD), with *C carriers showing a delayed sleep onset and worse insomnia. Sleep phase delay and insomnia associate with suicide in the general population.

METHODS

We investigated the effects of rs1801260, and of exposure to stressful life events, on current suicidal ideation and history of suicide attempts in 87 depressed patients with BD.

RESULTS

rs1801260*C carriers currently showed worse Hamilton Depression Rating Scale scores for suicide and worse ratings for depressive cognitive distortions. Previous history of attempted suicide associated with exposure to higher stressful events in the early life, with rs1801260*C carriers showing a higher dependency of the modeled probability of attempting suicide on the severity of exposure to early stress.

DISCUSSION

CLOCK rs1801260 modulated the relationship between early stress, adult history of attempted suicide and current suicide ideation. Factors affecting the biological clock can influence "non-clock" core psychopathological features of mood disorders.

The effect of poor sleep quality on mood outcome differs between men and women: A longitudinal study of bipolar disorder

BACKGROUND

Sleep disturbance is bi-directionally related to mood de-stabilization in bipolar disorder (BD), and sleep quality differs in men and women. We aimed to determine whether perception of poor sleep quality would have a different effect on mood outcome in men versus women.

METHODS

We assessed association between sleep quality (Pittsburgh Sleep Quality Index (PSQI)) at study intake and mood outcome over 2 years in subjects from the Prechter Longitudinal Study of Bipolar Disorder (N=216; 29.6% males). The main outcome measure was the severity, variability, and frequency of mood episodes measured by self-report over 2 years of follow-up. Multivariable linear regression models stratified by sex examined the relationship between PSQI with mood outcomes, while age, stressful life events, mood state and neuroticism at baseline were controlled.

RESULTS

In women, poor sleep quality at baseline predicted increased severity (B=0.28, p<0.001) and frequency of episodes (B=0.32, p<0.001) of depression, and poor sleep quality was a stronger predictor than baseline depression; poor sleep quality predicted increased severity (B=0.19, p<0.05) and variability (B=0.20, p<0.05) of mania, and frequency of mixed episodes (B=0.27, p<0.01). In men, baseline depression and neuroticism were stronger predictors of mood outcome compared to poor sleep quality.

LIMITATIONS

We measured perception of sleep quality, but not objective changes in sleep.

CONCLUSIONS

In a longitudinal study of BD, women reported poorer perceived sleep quality than men, and poor sleep quality predicted worse mood outcome in BD. Clinicians should be sensitive to addressing sleep complaints in women with BD early in treatment to improve outcome in BD.

The longitudinal course of sleep timing and circadian preferences in adults with bipolar disorder

OBJECTIVES

To study the longitudinal course of sleep timing and circadian preferences in individuals with bipolar disorder (BP) compared to individuals with non-BP psychopathology and healthy controls.

METHODS

Individuals with bipolar I and bipolar II disorder (n = 257), non-BP psychopathology (n = 105), and healthy controls (n = 55) (mean age 40.2 years, 21.3% male, 85.1% Caucasian) were followed on average every 27 months for a mean of four years. Sleep timing parameters and circadian preference were reported using the Sleep Timing Questionnaire and The Composite Scale for Morningness. Group comparisons were adjusted for multiple comparisons and between-group differences in demographic variables and psychopharmacological treatment.

RESULTS

Regardless of their current mood state, individuals with BP showed more sleep onset latency (SOL), wakening after sleep onset (WASO), and evening preference in comparison to both individuals with non-BP psychopathology and healthy controls. Individuals with BP also showed less stability of bed and awakening times in comparison to the other two groups, though these results were dependent on mood state. Non-BP individuals only showed more WASO and less stability in bed and awakening times before work/school days than healthy controls. Adjusting for comorbid disorders yielded similar results. Within-group analyses found little to no effect of time and BP subtype on sleep timing and circadian preference.

CONCLUSIONS

Disturbances of sleep timing are prominent in individuals with BP. These disturbances are worse during mood episodes, but still apparent during euthymic periods. Evening preference was not associated with polarity type, or mood state in BP, suggesting that this characteristic may be a trait marker.

Lamotrigine and GABAA receptor modulators interact with menstrual cycle phase and oral contraceptives to regulate mood in women with bipolar disorder

OBJECTIVES

To examine the occurrence of menstrually-entrained mood cycling in women with treated bipolar disorder as compared to healthy controls, and to explore whether there is a specific effect of lamotrigine in dampening menstrually-entrained cyclicity of mood.

METHODS

Observational comparison study of daily self-ratings of mood, sleep, and insomnia obtained over a mean of four menstrual cycles in 42 women with bipolar disorder taking lamotrigine as part of their treatment, 30 women with bipolar disorder receiving mood stabilizing regimens without lamotrigine, and 13 healthy controls, all with physiological menstrual cycles. Additional exploratory analysis of interactions between psychopharmacological regimen and hormonal contraceptive use in the group of women with bipolar disorder, with the addition of 19 women with bipolar disorder who were using hormonal contraceptives.

RESULTS

Women treated for bipolar disorder manifested lower average mood, longer average nightly sleep duration, and greater fluctuations in mood and sleep across menstrual cycle phases than healthy controls. Women with bipolar disorder who were taking lamotrigine had less fluctuation in mood both within and across menstrual cycle phases, and were more similar to the control group than to women with bipolar disorder who were not taking lamotrigine in this respect. In addition, medications with GABA-A receptor modulating effects were found to result in improved mood ratings when combined with hormonal contraceptives.

CONCLUSIONS

Menstrually-entrained mood fluctuation is present in women treated for bipolar disorder to a greater degree than in healthy controls. Lamotrigine may be of use in mitigating this fluctuation. GABA-A receptor modulators in general may act synergistically with hormonal contraceptives to enhance mood in women with bipolar disorder; this hypothesis merits further study.

Nonlinear dynamics of mood regulation in bipolar disorder

OBJECTIVES

We sought to study the underlying dynamic processes involved in mood regulation in subjects with bipolar disorder and healthy control subjects using time-series analysis and to then analyze the relation between anxiety and mood using cross-correlation techniques.

METHODS

We recruited 30 healthy controls and 30 euthymic patients with bipolar disorder. Participants rated their mood, anxiety, and energy levels using a paper-based visual analog scale; and they also recorded their sleep and any life events. Information on these variables was provided over a three-month period on a daily basis, twice per day. We analyzed the data using Box-Jenkins time series analysis to obtain information on the autocorrelation of the series (for mood) and cross-correlation (mood and anxiety series).

RESULTS

Throughout the study, we analyzed 10,170 data points. Self-ratings for mood, anxiety, and energy were normally distributed in both groups. Autocorrelation functions for mood in both groups were governed by the autoregressive integrated moving average (ARIMA) (1,1,0) model, which means that current values in the series were related to one previous point only. We also found a negative cross-correlation between mood and anxiety.

CONCLUSIONS

Mood can be considered a memory stochastic process; it is a flexible, dynamic process that has a 'short memory' both in healthy controls and euthymic patients with bipolar disorder. This process may be quite different in untreated patients or in those acutely ill. Our results suggest that nonlinear measures can be applied to the study of mood disorders.

Cannabis use and mania symptoms: a systematic review and meta-analysis

BACKGROUND

Whilst cannabis use appears to be a causal risk factor for the development of schizophrenia-related psychosis, associations with mania remain relatively unknown. This review aimed to examine the impact of cannabis use on the incidence of manic symptoms and on their occurrence in those with pre-existing bipolar disorder.

METHODS

A systematic review of the scientific literature using the PRISMA guidelines. PsychINFO, Cochrane, Scopus, Embase and MEDLINE databases were searched for prospective studies.

RESULTS

Six articles met inclusion criteria. These sampled 2391 individuals who had experienced mania symptoms. The mean length of follow up was 3.9 years. Studies support an association between cannabis use and the exacerbation of manic symptoms in those with previously diagnosed bipolar disorder. Furthermore, a meta-analysis of two studies suggests that cannabis use is associated with an approximately 3-fold (Odds Ratio: 2.97; 95% CI: 1.80-4.90) increased risk for the new onset of manic symptoms.

LIMITATIONS

We were only able to identify a small number of studies of variable quality, thus our conclusions remain preliminary.

CONCLUSIONS

Our findings whilst tentative, suggest that cannabis use may worsen the occurrence of manic symptoms in those diagnosed with bipolar disorder, and may also act as a causal risk factor in the incidence of manic symptoms. This underscores the importance of discouraging cannabis use among youth and those with bipolar disorder to help prevent chronic psychiatric morbidity. More high quality prospective studies are required to fully elucidate how cannabis use may contribute to the development of mania over time.

The development and course of bipolar spectrum disorders: an integrated reward and circadian rhythm dysregulation model

In this article, we present and review the evidence for two major biopsychosocial theories of the onset and course of bipolar spectrum disorders (BSDs) that integrate behavioral, environmental, and neurobiological mechanisms: the reward hypersensitivity and the social/circadian rhythm disruption models. We describe the clinical features, spectrum, age of onset, and course of BSDs. We then discuss research designs relevant to demonstrating whether a hypothesized mechanism represents a correlate, vulnerability, or predictor of the course of BSDs, as well as important methodological issues. We next present the reward hypersensitivity model of BSD, followed by the social/circadian rhythm disruption model of BSD. For each model, we review evidence regarding whether the proposed underlying mechanism is associated with BSDs, provides vulnerability to the onset of BSDs, and predicts the course of BSDs. We then present a new integrated reward/circadian rhythm (RCR) dysregulation model of BSD and discuss how the RCR model explains the symptoms, onset, and course of BSDs. We end with recommendations for future research directions.

Analysis of actigraph parameters for relapse prediction in bipolar disorder: a feasibility study

The paper presents a framework for early identification of prodromal syndromes od mania or depression in bipolar disorder. The framework may mitigate relapses and improve patient functioning. The methodology consists of long-term actigraphy monitoring and simplified self-assessment tool to determine manic or depression events. Eight patients were involved in the feasibility study, spanning period of 150 months, resulting in 17 relapses and 3 hospitalizations in total. We concluded that the most promising parameter extracted from actigraphy recording is a circadian rhythm's interdaily stability. Using developed trend analysis applied on interdaily stability parameter, we achieved sensitivity and specificity about 65, resp. 68. We hypothesized that this performance is both mainly due to missing values in data and due to small amount of relapses.

Evidence of weekly cyclicity in mood and functional impairment in those with a bipolar disorder

A key characteristic of bipolar disorder is fluctuation in mood symptoms and functional capacity, yet assessment of bipolar symptomatology often relies heavily on interval measurement that is unable to capture the full range of daily symptom variability and severity. The current study provides a detailed analysis of the variability in mood symptoms, functional impairment and medication compliance in a large sample of individuals newly diagnosed with bipolar disorder. Individuals diagnosed with bipolar disorder in the previous 12 months (n=192) rated their mood, functional impairment, medication compliance and symptom triggers daily over 10 consecutive weeks. High mood, low mood and functional impairment were found to vary on a weekly cycle, independently of medication compliance. Low mood and functional impairment were worse on weekdays, particularly Mondays and Tuesdays, whereas mood was most elevated on Saturdays. Work-related stressors were the most common symptom triggers on weekdays, whereas sleep-related problems and positive social events were the most common triggers on weekends. This study provides evidence that individuals newly diagnosed with bipolar disorder experience fluctuations in mood and functioning that vary according to a weekly cycle. This finding has implications for the assessment and treatment of patients, and for future research.

Postpartum mania in a man with bipolar disorder: case report and a review of the role of sleep loss

BACKGROUND

In contrast to postpartum mood episodes in women with bipolar disorder, little is known about the risk of recurrence in men with bipolar disorder who have just become fathers.

CASE REPORT

We present the case of a man with bipolar disorder who had a manic episode immediately after becoming a father. His spouse had a normal pregnancy, and delivery started during daytime and lasted until the early morning hours. The patient subsequently developed a manic episode, which had a major impact on the family.

CONCLUSIONS

There is a well-known relationship between sleep loss and the occurrence of a manic episode. The study of psychopathology in the postpartum period in relation to sleep disturbance refers mainly to women. Disturbance of sleep patterns in the perinatal and postpartum period may also negatively impact the course of bipolar disorder in the father. In cases of pregnancy of a male bipolar disorder patient's spouse, preventive strategies for the postpartum period should be planned in advance.

The association between immune activation and manic symptoms in patients with a depressive disorder

Although recent studies have shown that immunological processes play an important role in the pathophysiology of mood disorders, immune activation may only be present in specific subgroups of patients. Our study aimed to examine whether immune activation was associated with (a) the presence of manic symptoms and (b) the onset of manic symptoms during 2 years of follow-up in depressed patients. Patients with a depressive disorder at baseline (N=957) and healthy controls (N=430) were selected from the Netherlands Study of Depression and Anxiety. Assessments included lifetime manic symptoms at baseline and two-year follow up, as well as C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) at baseline. Within depressed patients, immune activation was not related to the presence or absence of lifetime manic symptoms at baseline. However, CRP levels were strongly elevated in depressed men who developed manic symptoms compared with those who did not develop manic symptoms over 2 years (P<0.001, Cohen's d=0.89). IL-6 and TNF-α were also higher in depressed men with an onset of manic symptoms, but this association was not significant. However, we found that the onset of manic symptoms was particularly high in men with multiple elevated levels of inflammatory markers. Depressed men who developed manic symptoms during follow-up had increased immunological activity (especially CRP) compared with depressed men who did not develop manic symptoms. Further research should explore whether a treatment approach focusing on inflammatory processes may be more effective in this specific subgroup of depressed patients.

Insomnia comorbid to severe psychiatric illness

In psychiatric illness, there is a growing body of evidence indicating that sleep disturbances exert a detrimental influence on the course of these disorders and contribute to impaired function. Even when psychiatric disorders are successfully treated or stabilized, insomnia and other sleep disturbances often fail to remit. The present review focuses on sleep in two severe mental illnesses, namely bipolar disorder and schizophrenia. This article discusses the role of sleep disturbances and altered sleep architecture in relation to symptom status, functional impairment, quality of life, and the course of these disorders. Current evidence regarding pharmacological and psychological treatment approaches for insomnia in these populations is presented. This review also notes considerations for adapting Cognitive Behavioral Therapy for insomnia (CBT-I) procedures for severe mental illness and proposes directions for future research.

Chronobiology of mood disorders

OBJECTIVE

As part of a series of papers examining chronobiology ['Getting depression clinical guidelines right: time for change?' Kuiper et al. Acta Psychiatr Scand 2013;128(Suppl. 444):24-30; and 'Manipulating melatonin in managing mood' Boyce & Hopwood. ActaPsychiatrScand 2013;128(Suppl. 444):16-23], in this article, we review and synthesise the extant literature pertaining to the chronobiology of depression and provide a preliminary model for understanding the neural systems involved.

METHOD

A selective literature search was conducted using search engines such as MEDLINE/PubMed, combining terms associated with chronobiology and mood disorders.

RESULTS

We propose that understanding of sleep-wake function and mood can be enhanced by simultaneously considering the circadian system, the sleep homoeostat and the core stress system, all of which are likely to be simultaneously disrupted in major mood disorders. This integrative approach is likely to allow flexible modelling of a much broader range of mood disorder presentations and phenomenology.

CONCLUSION

A preliminary multifaceted model is presented, which will require further development and testing. Future depression research should aim to examine multiple systems concurrently in order to derive a more sophisticated understanding of the underlying neurobiology.

Sleep and dreaming are for important matters

Recent studies in sleep and dreaming have described an activation of emotional and reward systems, as well as the processing of internal information during these states. Specifically, increased activity in the amygdala and across mesolimbic dopaminergic regions during REM sleep is likely to promote the consolidation of memory traces with high emotional/motivational value. Moreover, coordinated hippocampal-striatal replay during NREM sleep may contribute to the selective strengthening of memories for important events. In this review, we suggest that, via the activation of emotional/motivational circuits, sleep and dreaming may offer a neurobehavioral substrate for the offline reprocessing of emotions, associative learning, and exploratory behaviors, resulting in improved memory organization, waking emotion regulation, social skills, and creativity. Dysregulation of such motivational/emotional processes due to sleep disturbances (e.g., insomnia, sleep deprivation) would predispose to reward-related disorders, such as mood disorders, increased risk-taking and compulsive behaviors, and may have major health implications, especially in vulnerable populations.

Behavioral treatment of insomnia in bipolar disorder

Sleep disturbance is common in bipolar disorder. Stimulus control and sleep restriction are powerful, clinically useful behavioral interventions for insomnia, typically delivered as part of cognitive-behavioral therapy for insomnia (CBT-I). Both involve short-term sleep deprivation. The potential for manic or hypomanic symptoms to emerge after sleep deprivation in bipolar disorder raises questions about the appropriateness of these methods for treating insomnia. In a series of patients with bipolar disorder who underwent behavioral treatment for insomnia, the authors found that regularizing bedtimes and rise times was often sufficient to bring about improvements in sleep. Two patients in a total group of 15 patients reported mild increases in hypomanic symptoms the week following instruction on stimulus control. Total sleep time did not change for these individuals. Two of five patients who underwent sleep restriction reported mild hypomania that was unrelated to weekly sleep duration. Sleep restriction and stimulus control appear to be safe and efficacious procedures for treating insomnia in patients with bipolar disorder. Practitioners should encourage regularity in bedtimes and rise times as a first step in treatment, and carefully monitor changes in mood and daytime sleepiness throughout the intervention.

Sleep disturbances in bipolar disorder during remission

BACKGROUND

While sleep disturbances associated with bipolar disorder's depression and mania phases are well documented, the literature regarding sleep during remission phases is less consistent. The present study's aim was to describe the nature and severity of sleep difficulties in individuals with bipolar disorder (BD) during remission phases.

METHODS

Fourteen participants with BD were compared to 13 participants with primary insomnia and 13 without mental health disorders or insomnia on different sleep and daytime functioning parameters using actigraphy, sleep diaries and self-report measures.

RESULTS

Results suggest that sleep of individuals with BD was similar to that of individuals without mental health disorders or insomnia, but differed from that of individuals with insomnia. Nevertheless, participants with BD still presented sleep complaints and, like individuals with insomnia, were less active in the daytime, carried on their daily activities at more variable times from day to day, and reported more daytime sleepiness.

LIMITATIONS

Patients were taking medications and the limited sample size did not permit comparison of sleep parameters between bipolar I and bipolar II patients.

CONCLUSIONS

Psychological interventions aimed at encouraging the adoption of more stable sleep and daily routines might be helpful in helping individuals with BD cope more efficiently with some of these complaints.

Evaluating sleep in bipolar disorder: comparison between actigraphy, polysomnography, and sleep diary

OBJECTIVES

Bipolar disorder is an illness characterized by sleep and circadian disturbance, and monitoring sleep in this population may signal an impending mood change. Actigraphy is an important clinical and research tool for examining sleep, but has not yet been systematically compared to polysomnography or sleep diary in bipolar disorder. The present study compares actigraphy, polysomnography, and sleep diary estimates of five standard sleep parameters in individuals with bipolar disorder and matched controls across two nights of assessment.

METHODS

Twenty-seven individuals who met diagnostic criteria for bipolar disorder type I or II and were currently between mood episodes, along with 27 matched controls with no history of psychopathology or sleep disturbance, underwent two nights of research laboratory monitoring. Sleep was estimated via polysomnography, actigraphy, and sleep diary.

RESULTS

Over the 108 nights available for comparison, sleep parameter estimates from actigraphy and polysomnography were highly correlated and did not differ between the two groups or across the two nights for sleep onset latency, wake after sleep onset, number of awakenings, total sleep time, or sleep efficiency percentage. The medium wake threshold algorithm in the actigraphy software was the most concordant with polysomnography and diaries across the five sleep parameters. Concordance between actigraphy, polysomnography, and sleep diary was largely independent of insomnia presence and medication use.

CONCLUSIONS

Actigraphy is a valid tool for estimating sleep length and fragmentation in bipolar disorder.

The vigilance regulation model of affective disorders and ADHD

According to the recently proposed vigilance model of affective disorders (vigilance in the sense of "brain arousal"), manic behaviour is partly interpreted as an autoregulatory attempt to stabilise vigilance by creating a stimulating environment, and the sensation avoidance and withdrawal in Major Depressive Disorder (MDD) is seen as an autoregulatory reaction to tonically increased vigilance. Indeed, using a newly developed EEG-based algorithm, hyperstable vigilance was found in MDD, and the contrary, with rapid drops to sleep stages, in mania. Furthermore, destabilising vigilance (e.g. by sleep deprivation) triggers (hypo)mania and improves depression, whereas stabilising vigilance, e.g. by prolonged sleep, improves mania. ADHD and mania have common symptoms, and the unstable vigilance might be a common pathophysiology. There is even evidence that psychostimulants might ameliorate both ADHD and mania. Hyperactivity of the noradrenergic system could explain both the high vigilance level in MDD and, as recently argued, anhedonia and behavioural inhibition. Interestingly, antidepressants and electroconvulsions decrease the firing rate of neurons in the noradrenergic locus coeruleus, whereas many antimanic drugs have opposite effects.

Social support and social strain in inter-episode bipolar disorder

OBJECTIVES

This study focused on social support and social strain and their cross-sectional associations with instabilities in sleep and social rhythms in inter-episode bipolar disorder (BD).

METHODS

Thirty-five adults diagnosed with inter-episode BD type I and 38 healthy controls completed measures of perceived social support and social strain. Group differences in support and strain were examined. Within the BD group, instabilities in sleep and social rhythms were assessed with 28 days of daily diary and actigraphy. Correlation and regression analyses were used to examine cross-sectional and prospective associations between social support, social strain, instabilities in sleep and social rhythms, and mood symptoms.

RESULTS

The BD group reported lower social support and higher social strain than the control group. Additionally, social strain was positively correlated with manic and depressive symptoms in the BD group. Furthermore, there was a cross-sectional association between social support and more stable sleep on actigraphy in the BD group, although social support did not predict future sleep instability.

CONCLUSIONS

These results indicate that inter-episode BD is associated with deficient social support and elevated social strain compared to controls, and that this may be due to persistent inter-episode mood symptoms. Social strain may be particularly important given its association with manic and depressive symptoms. The results also raise the possibility that sleep instability is related to poor social support in BD.

Overlapping prefrontal systems involved in cognitive and emotional processing in euthymic bipolar disorder and following sleep deprivation: a review of functional neuroimaging studies

Prefrontal cortex (PFC) mediated cognitive and emotional processing deficits in bipolar disorder lead to functional limitations even during periods of mood stability. Alterations of sleep and circadian functioning are well-documented in bipolar disorder, but there is little research directly examining the mechanistic role of sleep and/or circadian rhythms in the observed cognitive and emotional processing deficits. We systematically review the cognitive and emotional processing deficits reliant upon PFC functioning of euthymic patients with bipolar disorder and in healthy individuals deprived of sleep. The evidence from two parallel lines of investigation suggests that sleep and circadian rhythms may be involved in the cognitive and emotional processing deficits seen in bipolar disorder through overlapping neurobiological systems. We discuss current models of bipolar highlighting the PFC-limbic connections and discuss inclusion of sleep-related mechanisms. Sleep and circadian dysfunction is a core feature of bipolar disorder and models of neurobiological abnormalities should incorporate chronobiological measures. Further research into the role of sleep and circadian rhythms in cognition and emotional processing in bipolar disorder is warranted.

Sleep disturbance in euthymic bipolar patients

Sleep disturbance is a common feature during mood episodes in bipolar disorder. The aim of this study was to investigate the prevalence of such symptoms among euthymic bipolar patients, and their association with risk for mood episode recurrence. A cohort of bipolar I and II subjects participating in the Systematic Treatment Enhancement Program for Bipolar Disorder who were euthymic for at least 8 weeks were included in this analysis. Survival analysis was used to examine the association between sleep disturbance on the Montgomery-Asberg Depression Rating Scale (MADRS) and recurrence risk. A total of 73/483 bipolar I and II subjects reported at least mild sleep disturbance (MADRS sleep item ≥2) for the week prior to study entry. The presence of sleep problems was associated with a history of psychosis, number of previous suicide attempts, and anticonvulsant use. Sleep disturbance at study entry was significantly associated with risk for mood episode recurrence. Sleep disturbance is not uncommon between episodes for individuals with bipolar disorder and may be associated with a more severe course of illness. This suggests that sleep disturbance is an important prodromal symptom of bipolar disorder and should be considered a target for pharmacologic or psychosocial maintenance treatment.

Restless pillow, ruffled mind: sleep and affect coupling in interepisode bipolar disorder

Disturbances in sleep and affect are prominent features of bipolar disorder, even during interepisode periods. Few longitudinal studies have prospectively examined the relationship between naturally occurring sleep and affect, and no studies to date have done so during interepisode periods of bipolar disorder and using the entire set of "gold standard" sleep parameters. Participants diagnosed with bipolar I disorder who were interepisode (n = 32) and healthy controls (n = 36) completed diagnostic and symptom severity interviews, and a daily sleep and affect diary, as well as an actigraphy sleep assessment, for eight weeks (M = 54 days, ± 8 days). Mutual information analysis was used to assess the degree of statistical dependence, or coupling, between time series data of sleep and affect. As measured by actigraphy, longer sleep onset latency was coupled with higher negative affect more strongly in the bipolar group than in the control group. As measured by sleep diary, longer wakefulness after sleep onset and lower sleep efficiency were coupled with higher negative affect significantly more strongly in the bipolar group than in the control group. By contrast, there were no significant differences between groups in the degree of coupling between any measures of sleep and positive affect. Findings support the coupling of sleep disturbance and negative affect during interepisode bipolar disorder. Ongoing monitoring of sleep-affect coupling may provide an important target for intervention in bipolar disorder.

Poor sleep at baseline predicts worse mood outcomes in patients with co-occurring bipolar disorder and substance dependence

BACKGROUND

Sleep problems are common in patients with bipolar disorder and have been shown to predict subsequent mood symptoms. Sleep problems have also been shown to lead to worse substance use outcomes in individuals with substance use disorder. However, the relationship between sleep and clinical outcomes in a population with co-occurring bipolar disorder and substance use disorder is unclear.

METHOD

This secondary analysis included 60 outpatients (mean age = 38.1 years; recruited via advertisements, fliers, clinician referrals, and hospital treatment programs) who met DSM-IV criteria for both bipolar disorder and substance use disorder (assessed with the Structured Clinical Interview for DSM-IV Axis I Disorders) and who participated in a randomized clinical trial comparing integrated group therapy for bipolar disorder and substance use disorder to group drug counseling for substance use disorder alone. A 12-week treatment period preceded a 24-week follow-up. Poor sleep was assessed with the Pittsburgh Sleep Quality Index, which provides 7 component subscores and an overall sleep score. Data were collected from August 2003 through April 2007.

RESULTS

When analyses were controlled for baseline mood, substance use, and treatment condition, baseline sleep score predicted mood over the course of the 12-week treatment (β = 0.28; P < .05) and 24-week follow-up (β = 0.46; P < .01): worse sleep was associated with worse mood outcomes. Sleep was not associated with substance use outcomes.

CONCLUSIONS

Impaired sleep is a prognostic factor for mood outcomes in patients with co-occurring bipolar and substance use disorders. Further investigation is warranted into the long-term clinical outcomes of poor sleep in this population with co-occurring bipolar disorder and substance use disorder so that appropriate interventions can be developed.

Risk constellations prior to the development of bipolar disorders: rationale of a new risk assessment tool

BACKGROUND

The precise characterisation of a high risk status for the development of a psychiatric disorder and the question of how well this predicts disease manifestation is of major importance as negative consequences of late diagnosis and treatment have been well demonstrated. In the absence of well defined and disease specific biological markers for bipolar disorder, the recognition of premature stages must rely on combinations of risk factors that have been associated with later disease manifestation.

METHODS

A review of the literature and our experience from the Early Recognition Centre led us to identify symptom constellations.

RESULTS

Individual categories defined and grouped included: (I) genetic risk, (II) substance use, misuse or dependence, (III) diagnosis/suspected diagnosis of attention deficit hyperactivity disorder, (IV) pronounced creativity, (V) impairment in psychosocial functioning, (VI) subthreshold affective symptoms, and (VII) early symptomatology including (a) changes in sleep and circadian rhythm, (b) changes in mood, mood swings/affective lability, (c) fearfulness/anxiety, and (d) dissociative symptoms. These risk constellations were operationalised and a new risk assessment instrument, the Early Phase Inventory for Bipolar Disorders (EPIbipolar) was developed.

LIMITATIONS

Challenges regarding the validity of the data on which the instrument is based, specificity of and correlations between risk categories, and ethical considerations were encountered.

CONCLUSIONS

Further use of EPIbipolar in research should help to refine prodromal features and narrow these down to a less cumbersome core that can be used to develop a shortened tool for use in clinical care. Prospective longitudinal research is needed to establish the predictive validity of this novel bipolar disorder risk assessment tool.

A test of the bidirectional association between sleep and mood in bipolar disorder and insomnia

The present study investigates sleep, mood, and the proposed bidirectional relationship between the two in psychiatric disorders. Participants with interepisode bipolar disorder (n = 49), insomnia (n = 34), and no psychiatric history (n = 52) completed seven consecutive days of sleep diaries and mood measures. The interepisode bipolar and insomnia participants exhibited greater sleep disturbance than the healthy control individuals. Negative mood was equally heightened in both interepisode bipolar disorder and insomnia, and there were no differences between the three groups in positive mood. Total wake time was associated with next morning negative mood in bipolar disorder, whereas evening negative mood was associated with subsequent total wake time in both bipolar disorder and insomnia. Additionally, positive mood was associated with subsequent total wake time for the insomnia group. Results support the theory that disruptions in nighttime sleep and daytime mood may be mutually maintaining and suggest the potential importance of transdiagnostic or universal processes.

Sleep matters: sleep functioning and course of illness in bipolar disorder

BACKGROUND

Few studies have prospectively examined the relationships of sleep with symptoms and functioning in bipolar disorder.

METHODS

The present study examined concurrent and prospective associations between total sleep time (TST) and sleep variability (SV) with symptom severity and functioning in a cohort of DSM-IV bipolar patients (N = 468) participating in the National Institute of Mental Health Systematic Treatment Enhancement Program for Bipolar Disorder (STEP-BD), all of whom were recovered at study entry.

RESULTS

Concurrent associations at study entry indicated that shorter TST was associated with increased mania severity, and greater SV was associated with increased mania and depression severity. Mixed-effects regression modeling was used to examine prospective associations in the 196 patients for whom follow-up data were available. Consistent with findings at study entry, shorter TST was associated with increased mania severity, and greater SV was associated with increased mania and depression severity over 12 months.

DISCUSSION

These findings highlight the importance of disrupted sleep patterns in the course of bipolar illness.

The precipitants of manic/hypomanic episodes in the context of bipolar disorder: a review

BACKGROUND

Mania/hypomania is the hallmark feature of bipolar disorder. This paper aims to review the current evidence in relation to factors hypothesised to precipitate bipolar mania/hypomania, and suggest areas for future research.

METHODS

A selective review of original and review papers was conducted. The electronic databases 'PsycINFO' and 'PubMed' were searched using the following search strings: "bipolar disorder" or "mania" or "hypomania" or "manic-depression" with "triggers" or "precipitants" or "precedents" or "predictors".

RESULTS

There is evidence that goal attainment events, antidepressant medication, disrupted circadian rhythms, spring/summer seasonal conditions, and more tentatively, stressful life events and high emotional expression, may precipitate bipolar mania/hypomania in susceptible individuals. Evidence from case reports and clinical observations are also reported.

DISCUSSION

The pathways to bipolar mania/hypomania may be many and varied, and many of these pathways may be outside the awareness of individuals with bipolar disorder. Greater awareness of the broad number of precipitating factors is needed to inform self-management and psycho-educational programs to build resilience to further episodes. Future research is needed to explore what other factors may precipitate bipolar mania/hypomania, and to determine why some factors may precipitate mania/hypomania in some individuals with bipolar I or II disorder but not in others.

Daily variations in sleep-wake patterns and severity of psychopathology: a pilot study in community-dwelling individuals with chronic schizophrenia

The daily co-occurrence of change in sleep characteristics and psychopathology was examined in six individuals with schizophrenia and seven healthy controls using a prospective assessment of rest-activity patterns conducted in the person's home for up to 28 days. The results provide preliminary evidence that a change in sleep-wake timing is followed by a change in symptom severity.

The role of disturbed sleep in the early recognition of bipolar disorder: a systematic review

OBJECTIVES

Severely disturbed sleep is known to occur during and shortly prior to the onset of mood episodes in bipolar disorder. Whether alterations in sleep occur parallel and as part of the disease process or whether they represent a trait existent before the onset of the disorder itself remains unclear.

METHODS

A systematic review evaluating all published data on the occurrence of disordered sleep prior to the onset of the first mood episode was conducted.

RESULTS

The evidence cited within this paper suggests that sleep disturbances frequently precede bipolar disorder by several years and convey an elevated long-term risk for developing any kind of mood disorder. Disordered sleep appears to emerge about the time of puberty and remains persistently elevated in individuals at high risk.

CONCLUSION

Disturbed sleep appears to be an early symptom of bipolar disorder but further research, especially longitudinal studies in individuals at high risk, will be required to characterize the type and patterns more precisely.

Sleep and circadian rhythm abnormalities in the pathophysiology of bipolar disorder

Among other factors, bipolar disorder is characterized by disturbances in sleep and biological rhythms that typically cycle over a 24-h, or circadian period. Indeed, almost all of the functions that constitute symptoms of depression and mania (changes in mood, energy, sleep, interest, appetite, capacity for concentration, etc.) show relatively regular variation over the circadian period. Thus, it would appear logical to search for clues to the pathophysiology of bipolar disorder in the function of the circadian timing system (Wirz-Justice in Int Clin Psychopharmacol 21:S11-S15, 2006). In this chapter, we review the known sleep and biological rhythm abnormalities associated with bipolar disorder. We describe the nature of these circadian rhythm abnormalities and review the evidence supporting their role in bipolar episodes. Last, we discuss a number of pharmacologic and psychosocial treatments for bipolar disorder that target sleep and biological rhythm abnormalities, and we examine their effect on bipolar episodes and symptoms.

Time of mood switches in ultra-rapid cycling disorder: a brief review

The aim of this review is to assess the typical time of day that mood switches occur in ultra-rapid cycling disorder. It shall be determined, whether switches into depression or (hypo)mania are likelier to occur at particular times of the day or night, and whether a pattern of mood switch times can be discerned for different cycle lengths. Case reports giving information about cycle lengths and the times of day when switches have occurred were systematically compiled (sources: Medline and Web of Science). Cases with ultra-rapid (cycle lengths of days to weeks, including 48-h cycling) or ultra-ultra-rapid cycling (cycle lengths up to 24 h) were included (35 publications with 42 case reports). In cases with cycle lengths of days to weeks (n=11), switches appeared to occur at any time of the day. Patients with regular 48-h cycling (n=28) switched to depression or mania most often during nighttime hours. In all three patients with cycle lengths up to 24 h (ultra-ultra-rapid cycling), switches into depression occurred at night and switches into mania occurred at daytime. These findings indicate that in patients with mood cycles of 48h or less the switch process is closely linked to circadian aspects.

Association between CLOCK 3111T/C and preferred circadian phase in Korean patients with bipolar disorder

Genes associated with circadian rhythms have been suggested to play an important role in the pathophysiology of bipolar disorder. A single nucleotide polymorphism (SNP) in the 3'-flanking region of CLOCK (3111T/C; rs1801260) has been reported to be associated with sleep disturbances and an increased recurrence rate in patients with bipolar disorder. We examined the association of CLOCK 3111T/C with bipolar disorder in 260 patients and 350 controls in a Korean population. CLOCK 3111T/C showed significant allelic and genotypic associations with bipolar disorder (P=0.012, P=0.033, respectively). Morningness/eveningness (M/E) was evaluated using the Composite Scale of Morningness (CSM) in 108 patients with bipolar disorder. In the subgroup analysis of the highest and lowest 25th percentile of M/E scores, significantly more C allele carriers were found among extreme evening types than among extreme morning types (P=0.041). After correcting for age, C allele carriers had lower M/E scores than those carrying the T/T genotype, but the association was not statistically significant. We also analyzed the association between age at onset (AAO) and CLOCK 3111T/C in the bipolar disorder group, and no association was found. Despite the relatively small sample sizes, these results support a possible role of the CLOCK 3111T/C SNP in bipolar disorder. Further studies with larger samples and more polymorphisms are necessary.

Circadian rhythms and sleep in bipolar disorder

OBJECTIVE

Biological rhythm pathways are highlighted in a number of etiological models of bipolar disorder, and the management of circadian instability appears in consensus treatment guidelines. There are, however, significant conceptual and empirical limitations on our understanding of a hypothesised link between circadian, sleep, and emotion regulation processes in bipolar disorder. The aim of this article is to articulate the limits of scientific knowledge in relation to this hypothesis.

METHODS

A critical evaluation of various literatures was undertaken. The basic science of circadian and sleep processes, their involvement in normal emotion regulation, and the types of evidence suggesting circadian/sleep involvement in bipolar disorder are reviewed.

RESULTS

Multiple lines of evidence suggest that circadian and sleep-wake processes are causally involved in bipolar disorder. These processes demonstrably interact with other neurobiological pathways known to be important in bipolar disorder, but are unique in that they are open to behavioural manipulation.

CONCLUSION

Further research into biological rhythm pathways to bipolar disorder is warranted. Person-environment feedback loops are fundamental to circadian adaptation, and models of circadian pathogenesis (and treatment) should recognize this complexity.

Coming to grips with complex disorders: genetic risk prediction in bipolar disorder using panels of genes identified through convergent functional genomics

We previously proposed and provided proof of principle for the use of a complementary approach, convergent functional genomics (CFG), combining gene expression and genetic data, from human and animal model studies, as a way of mining the existing GWAS datasets for signals that are there already, but did not reach significance using a genetics-only approach [Le-Niculescu et al., 2009b]. CFG provides a fit-to-disease prioritization of genes that leads to generalizability in independent cohorts, and counterbalances the fit-to-cohort prioritization inherent in classic genetic-only approaches, which have been plagued by poor reproducibility across cohorts. We have now extended our previous work to include more datasets of GWAS, and more recent evidence from other lines of work. In essence our analysis is the most comprehensive integration of genetics and functional genomics to date in the field of bipolar disorder. Biological pathway analyses identified top canonical pathways, and epistatic interaction testing inside these pathways has identified genes that merit future follow-up as direct interactors (intra-pathway epistasis, INPEP). Moreover, we have put together a panel of best P-value single nucleotide polymorphisms (SNPs), based on the top candidate genes we identified. We have developed a genetic risk prediction score (GRPS) based on our panel, and demonstrate how in two independent test cohorts the GRPS differentiates between subjects with bipolar disorder and normal controls, in both European-American and African-American populations. Lastly, we describe a prototype of how such testing could be used to categorize disease risk in individuals and aid personalized medicine approaches, in psychiatry and beyond.

Maladaptive behaviors are linked with inefficient sleep in individuals with developmental disabilities

The purpose of the current study was to assess the relations between nightly sleep patterns and the frequency of daily maladaptive behavior. Antecedent and consequential relations between sleep patterns and behavior were evaluated with time series analysis. Sleep efficiency and maladaptive behavior were determined for 20 female residents of an institutional care facility for adults with developmental disabilities. Daily maladaptive behavioral data and nightly sleep/awake logs were collected for 4 months for each participant. Efficient sleep patterns were significantly associated with lower frequencies of maladaptive behaviors. All lagged cross-correlations 8 days before and 8 days after an evening of sleep were significant. These findings suggested that inefficient sleep was associated with increased maladaptive behaviors and that the lagged associations reflected a chronic but not an acute linkage between sleep and behavior.

A dependence that empowers-the meaning of the conditions that enable a good life with bipolar disorder

The extensive suffering related to a complex life situation with bipolar disorder (BD) and the reported difference between care needs and the needs that are actually met implicates that there are still questions about management of life with BD that need to be answered. The present study therefore aims to describe the meaning of the conditions that enable a good life with BD. Ten persons, six women and four men (aged 30–61), diagnosed with BD were interviewed. A reflective lifeworld perspective based on phenomenological philosophy was used. The findings present the essential meaning of the conditions that enable a good life with BD as a dependence that empowers, which is further described by its constituents: “turning the course of life,” “protecting oneself from running out of energy,” “being needed,” “being oneself through reliable others,” “personal landmarks for navigating through life.” A voluntary chosen dependence, as described in the present study, is a new approach of care that enables a good life with BD, while enhancing own power, freedom, and control. The conditions that enable a good life with BD are more than separate supporting measures. Therefore a holistic perspective is preferable while providing care for individuals with BD.

Melatonin, circadian rhythms, and the clock genes in bipolar disorder

Sleep disturbances and dysregulation of circadian rhythms are core elements of bipolar disorder that might be involved in its pathogenesis. It has been proposed that patients with bipolar disorder have an abnormally shifted or arrhythmic circadian system and that the disturbance of circadian rhythms may be caused by an alteration in the circadian clock machinery. Chronotherapeutic strategies based on controlled exposures to environmental stimuli that act on biological rhythms have shown good efficacy in the treatment of illness episodes, thus confirming ex juvantibus the clinical relevance of internal timing in this illness.