Sleep in obsessive compulsive disorder: polysomnographic studies under baseline conditions and after experimentally induced serotonin deficiency

REM parameters in drug-free major depressive disorder: A systematic review and meta-analysis

Previous studies revealed that rapid eye movement (REM) parameters, such as REM latency (RL) and REM density (RD) could be used as electrophysiological markers of depression. Yet these finding should be re-tested in a comorbid-free and drug-free sample. The present systematic review and meta-analysis was conducted to investigate whether drug-free and comorbid-free patients with unipolar depression differentiate from controls with respect to the RL and RD. The PubMed and Web of Science databases were screened from inception to 23 January 2023 for case-control studies comparing RL and RD of patients with unipolar depression and controls. The primary outcome was the standard mean difference. The data were fitted with a random-effects model. Meta-regressions were conducted to investigate patient characteristics and effect size. Publication bias assessment was checked by Egger's Regression and funnel plot asymmetry. Among 43 articles accepted as eligible, 46 RL and 22 RD measurements were included in the meta-analysis. The results indicated shortened RL and increased RD in the patient group than controls. Neither Egger's regression nor funnel plot asymmetry were significant for publication bias. In conclusion, our results tested within drug-free and comorbid-free samples are in line with the literature.

The shared molecular mechanisms underlying aging of the brain, major depressive disorder, and Alzheimer's disease: The role of circadian rhythm disturbances

An association with circadian clock function and pathophysiology of aging, major depressive disorder (MDD), and Alzheimer's disease (AD) is well established and has been proposed as a factor in the development of these diseases. Depression and changes in circadian rhythm have been increasingly suggested as the two primary overlapping and interpenetrating changes that occur with aging. The relationship between AD and depression in late life is not completely understood and probably is complex. Patients with major depression or AD suffer from disturbed sleep/wake cycles and altered rhythms in daily activities. Although classical monoaminergic hypotheses are traditionally proposed to explain the pathophysiology of MDD, several clinical and preclinical studies have reported a strong association between circadian rhythm and mood regulation. In addition, a large body of evidence supports an association between disruption of circadian rhythm and AD. Some clock genes are dysregulated in rodent models of depression. If aging, AD, and MDD share a common biological basis in pathophysiology, common therapeutic tools could be investigated for their prevention and treatment. Nitro-oxidative stress (NOS), for example, plays a fundamental role in aging, as well as in the pathogenesis of AD and MDD and is associated with circadian clock disturbances. Thus, development of therapeutic possibilities with these NOS-related conditions is advisable. This review describes recent findings that link disrupted circadian clocks to aging, MDD, and AD and summarizes the experimental evidence that supports connections between the circadian clock and molecular pathologic factors as shared common pathophysiological mechanisms underlying aging, AD, and MDD.

Delayed circadian rhythms and insomnia symptoms in obsessive-compulsive disorder

BACKGROUND

Accumulating evidence implicates sleep and circadian rhythm disturbance in obsessive-compulsive disorder (OCD). However, a multimethod characterization of sleep and circadian rhythms in OCD, their association with symptom severity, and the functional relationship between these variables is lacking.

METHODS

The present study measured multiple indicators of sleep and circadian rhythms in a sample of adults with OCD, adults without OCD, and healthy controls (n = 74). Participants completed measures of morningness-eveningness, delayed sleep-wake phase disorder (DSWPD), insomnia symptoms, and OCD symptoms, as well as one week of sleep monitoring via a sleep diary and actigraphy.

RESULTS

Delayed circadian rhythms (higher eveningness, later mid-sleep timing, and higher rates of DSWPD) and higher insomnia symptoms were observed in those with OCD compared to healthy controls, as well as associations between delayed circadian rhythms and insomnia symptoms and OCD symptom severity across the full sample. Further, insomnia symptoms mediated the relationship between delayed circadian rhythms and OCD symptoms. In contrast, there were no links between total sleep time or sleep quality and OCD.

LIMITATIONS

Data collection during COVID-19 pandemic, correlational data, no physiological measure of circadian rhythms.

CONCLUSIONS

These findings highlight a robust association between delayed circadian rhythms and OCD and suggest insomnia symptoms may be one mechanism in this relationship. Sleep and circadian rhythm disturbance may be novel targets for OCD treatment.

ROLE OF GUT MICROBIOTA IN DEPRESSION: UNDERSTANDING MOLECULAR PATHWAYS, RECENT RESEARCH, AND FUTURE DIRECTION

Gut microbiota, also known as the "second brain" in humans because of the regulatory role it has on the central nervous system via neuronal, chemical and immune pathways. It has been proven that there exists a bidirectional communication between the gut and the brain. Increasing evidence supports that this crosstalk is linked to the etiology and treatment of depression. Reports suggest that the gut microbiota control the host epigenetic machinery in depression and gut dysbiosis causes negative epigenetic modifications via mechanisms like histone acetylation, DNA methylation and non-coding RNA mediated gene inhibition. The gut microbiome can be a promising approach for the management of depression. The diet and dietary metabolites like kynurenine, tryptophan, and propionic acid also greatly influence the microbiome composition and thereby, the physiological activities. This review gives a bird-eye view on the pathological updates and currently used treatment approaches targeting the gut microbiota in depression.

Nutritional importance of tryptophan for improving treatment in depression and diabetes

The importance of nutrients in our diet is becoming increasingly recognized. From the viewpoint of protein synthesis and other physiologic and metabolic functions, all amino acids are important, but some of these amino acids are not synthesized endogenously. This subset, called essential amino acids, comprise dietarily indispensable nutrients. Tryptophan, an essential amino acid, is the sole precursor of neuronal as well as peripheral serotonin (5-hydroxytryptamine). Its systemic or oral administration increases serotonin synthesis because tryptophan hydroxylase, the rate-limiting enzyme of 5-hydroxytryptamine biosynthesis, is physiologically unsaturated with its substrate. Central serotonin is implicated in a number of psychiatric illnesses, including depression, and in responses to stress. Acting peripherally, serotonin affects vasoconstriction, intestinal motility, control of T cell–mediated immunity, and liver and pancreatic functions. Depression and diabetes are 2 highly prevalent diseases that often coexist. There is evidence that occurrence of depression is 2–3 times higher in people with diabetes mellitus. A comorbid condition of diabetes and depression worsens the treatment and increases risk for death. Stress, known for its causal role in depression, can also enhance risk for diabetes. Stress-induced decreases in the circulating levels of tryptophan can impair brain and pancreatic serotonin-dependent functions to precipitate these diseases. The importance of tryptophan supplementation for improving therapeutic intervention in depression and diabetes is the focus of this article. A deficiency of this essential amino acid may enhance risk for depression as well as diabetes, and can also weaken treatment efficacy of medicinal compounds for treating these diseases. Guidelines for optimal levels of circulating tryptophan can help if supplements of this amino acid can improve treatment efficacy.

A systematic review of sleep problems in children and adolescents with obsessive compulsive disorder

There is growing interest in the relationship between obsessive-compulsive disorder (OCD) and sleep problems in youth, including the development of a theoretical model proposing how these disorders maintain each other. The model suggests that OCD symptoms are proposed to interfere with sleep duration (e.g., via increased arousal and delayed bedtime), which compounds OCD symptom severity during the daytime and into the evening, feeding back into the model. Whether the recent influx of research on sleep problems in youth with OCD supports this model is unknown. The primary aim of this systematic review was to characterize sleep problems in youth with OCD and evaluate whether current research supports previous theoretical inferences. Findings across 20 studies revealed a high prevalence of sleep problems among youth with OCD and support a bidirectional relationship. Studies largely did not assess hypothesized relationships proposed by the model; support for the model is therefore preliminary. A secondary aim was to assess the impacts of comorbidity and developmental stage. Findings suggest that in childhood, comorbid anxiety disorders may initially predate sleep problems, but they become mutually maintained over time; the role of comorbid depression appears to increase with age. Limitations, future directions, and clinical implications are discussed.

Sleep quality and its clinical associations in trichotillomania and skin picking disorder

BACKGROUND

Trichotillomania (TTM) is characterized by recurrent hair pulling and associated hair loss. Skin picking disorder (SPD) is characterized by recurrent skin picking and associated scarring or tissue damage. Both disorders are also accompanied by psychological distress and poor sleep. Very little, however, is known about lifestyle variables that may contribute to symptom severity in these disorders.

METHODS

We recruited 87 adults as part of a cross-sectional study of 3 groups (TTM, SPD, and non-affected). Clinical subjects (n=69) were compared with controls (n=18) on sleep quality as measured by Pittsburgh Sleep Quality Index (PSQI). We used partial least squares regression to identify which variables were significantly associated with poor sleep quality among those participants with TTM or SPD.

RESULTS

Clinical subjects had significantly poorer sleep quality than controls. Sleep quality was significantly related to older age, worse perceived stress, lower distress tolerance and greater impulsivity in adults with BFRBs. Poor sleep quality was associated with worse hair pulling symptom severity but not skin picking severity. Higher levels of comorbid mental disorders was also associated with worse sleep, above and beyond the impact of these other variables.

CONCLSUIONS

Poor sleep quality appears to be related to multiple variables. Further research is needed to determine causality and to tailor treatment to specific patient needs.

Sleep disturbances in obsessive-compulsive disorder: influence of depression symptoms and trait anxiety

BACKGROUND

Sleep disturbances have been reported in obsessive-compulsive disorder (OCD) patients, with heterogeneous results. The aim of our study was to assess sleep function in OCD and to investigate the relationship between sleep and the severity of obsessive-compulsive (OC) symptoms, depressive symptoms and trait anxiety.

METHODS

Sleep quality was measured in 61 OCD patients and 100 healthy controls (HCs) using the Pittsburgh Sleep Quality Index (PSQI). Multiple linear regression was conducted to explore the association between sleep and psychopathological measures; a mediation analysis was also performed.

RESULTS

OCD patients showed poor sleep quality and more sleep disturbances compared to HCs. The severity of depression, trait anxiety and OC symptomatology were correlated with poor sleep quality. Multiple linear regression analyses controlling for potential confounders revealed that the severity of depression and trait anxiety were independently related to poor sleep quality in OCD. A mediation analysis showed that both the severity of trait anxiety and depression mediate the relationship between the severity of OC symptoms and poor sleep quality among patients with OCD.

CONCLUSIONS

Our findings support the existence of sleep disturbances in OCD. Trait anxiety and depression play a key role in sleep quality among OCD patients.

The Association between Insomnia and Anxiety Symptoms in a Naturalistic Anxiety Treatment Setting

Objective/Background: Few studies have examined the relationship between insomnia and anxiety treatment outcomes in naturalistic settings. Furthermore, prior studies typically examine insomnia within a single anxiety diagnosis without accounting for the high overlap between disorders. Here we investigate the association between insomnia and multiple anxiety disorders over a course of cognitive behavioral treatment (CBT) in a naturalistic treatment setting. Participants: Insomnia was assessed in 326 patients seeking treatment at a clinic specializing in CBT for anxiety. Methods: Multilevel modeling was used to investigate whether insomnia moderated reductions in anxiety symptoms. A cross-lagged analysis tested for bidirectional effects between insomnia and anxiety. Multiple regression was used to investigate the relationship between insomnia and anxiety while controlling for the other anxiety disorders and depression. Results: While there was a significant reduction in insomnia during treatment in all anxiety disorders, the majority of the most severe patients remained in the clinical range at post-treatment. Baseline insomnia did not significantly moderate anxiety outcomes, suggesting that patients with high or low levels of insomnia will do equally well in CBT for anxiety. The bidirectional effect between insomnia and anxiety did not reach significance. Additionally, posttraumatic stress disorder, generalized anxiety disorder, and panic disorder were associated with the greatest endorsement of insomnia, after controlling for the overlap between disorders. Conclusions: Sleep problems may persist after anxiety treatment, suggesting that CBT for insomnia may be warranted during or after a course of CBT for anxiety. Importantly, baseline insomnia does not impede anxiety reduction during CBT.

Clarifying the role of sleep in depression: A narrative review

It has been established that 4.4 to 20% of the general population suffers from a major depressive disorder (MDD), which is frequently associated with a dysregulation of normal sleep-wake mechanisms. Disturbances of circadian rhythms are a cardinal feature of psychiatric dysfunctions, including MDD, which tends to indicate that biological clocks may play a role in their pathophysiology. Thus, episodes of depression and mania or hypomania can arise as a consequence of the disruption of zeitgebers (time cues). In addition, the habit of sleeping at a time that is out of phase with the body's other biological rhythms is a common finding in depressed patients. In this review, we have covered a vast area, emerging from human and animal studies, which supports the link between sleep and depression. In doing so, this paper covers a broad range of distinct mechanisms that may underlie the link between sleep and depression. This review further highlights the mechanisms that may underlie such link (e.g. circadian rhythm alterations, melatonin, and neuroinflammatory dysregulation), as well as evidence for a link between sleep and depression (e.g. objective findings of sleep during depressive episodes, effects of pharmacotherapy, chronotherapy, comorbidity of obstructive sleep apnea and depression), are presented.

Later Bedtimes Predict Prospective Increases in Symptom Severity in Individuals with Obsessive Compulsive Disorder (OCD): An Initial Study

Prior studies of sleep in individuals with OCD have often focused on sleep duration. Several studies have found that individuals with OCD sleep less than healthy controls while others have failed to find significant group differences. Addressing sleep timing has been much more rare, but have consistently shown that many individuals with severe OCD in inpatient facilities had markedly elevated rates of disruptions in sleep timing. We extend prior work by testing prospective relations between sleep and OC symptoms in individuals representing a range of OC symptom severity. Twenty-six individuals diagnosed with OCD, 18 healthy controls, and 10 with subthreshold OC symptoms, completed seven days of sleep diaries and OCD symptom ratings. Results showed that sleep timing (later bedtimes) predicted prospective increases in both obsessions and compulsions in individuals with OCD but not the other two groups. In contrast, there were no significant effects of sleep duration. The significant effects of sleep timing in the OCD group were maintained controlling for depressive symptoms and OCD symptoms did not predict prospective changes in sleep timing. In conclusion, there is increasing evidence that sleep timing may play an important role in OCD and additional work in this area is encouraged.

Effects of Viola odorata as an Add-On Therapy on Insomnia in Patients with Obsession or Depression: A Pilot Randomized Double-Blind Placebo-Controlled Trial

Objective: The present study was conducted to investigate the effect of Viola odorata extracted syrup on the quality and patterns of sleep in patients with depression or obsessive-compulsive disorder (OCD) as add-on therapy. Design: A pilot double-blind randomized placebo-controlled trial. Settings/Location: Psychiatric Clinic of Imam Hossein Hospital, Tehran, Iran. Subjects: Participants were 16-15 years of age with mild and moderate depression or OCD having insomnia. Interventions: This pilot study was conducted on patients with insomnia divided into two groups with depression (40 patients) or OCD (43 patients). Each group randomly assigned into two arms with the same conditions at baseline. The intervention arm daily received 5 mL V. odorata syrup every 12 h for 4 weeks, and the control arm received 5 mL placebo syrup every 12 h for 4 weeks. None of the participants was deprived of their routine treatment for depression or OCD. Outcome measures: The scores of insomnia symptoms were evaluated using total score of the Pittsburgh Sleep Quality Index (PSQI) and the scores of its components, the depression score using the final Beck depression inventory-II (BDI-II) score, and OCD score using the Yale-Brown Obsessive-Compulsive Scale (YBOCS). Results: The total PSQI score was found to be improved significantly in the intervention arms with depression or OCD (p < 0.001) compared with the corresponding control arms. Significant improvements were also observed in the final mean difference of BDI-II (p = 0.009) and YBOCS (p = 0.001) scores in the intervention arms. Conclusions: V. odorata syrup significantly improved insomnia symptoms and the scores of depression and OCD.

Sleep in the anxiety-related disorders: A meta-analysis of subjective and objective research

Although sleep disturbance is implicated in psychopathology, its role in anxiety-related disorders remains unclear. The present meta-analysis characterizes sleep disturbance in anxiety-related disorders collectively and individually. Subjective measures of total sleep time and sleep continuity were included with objective measures. Results indicate a large effect for increased subjective sleep disturbance (g = 2.16), medium effects for decreased total sleep time (g = -.40) and sleep continuity (g = -.49), and a small effect for decreased sleep depth (g = -.20) in anxiety-related disorders compared to healthy controls. Each anxiety-related disorder exhibited a distinct sleep disturbance pattern, suggesting that sleep may facilitate identification of unique biopsychological underpinnings. Effects were not moderated by comorbid depression and were similar in magnitude to those found for depression. Sleep disturbances, particularly decreased sleep continuity, may be a key pathology in the anxiety-related disorders that could highlight novel etiological mechanisms and intervention targets.

Developing and Testing a Novel, Computerized Insomnia and Anxiety Intervention to Reduce Safety Aids Among an at-Risk Student Sample: A Randomized Controlled Trial

Anxiety and insomnia disorders are two of the most common and costly mental health conditions. They are frequently comorbid, but current treatments do not target both. To streamline treatment, we developed a computerized intervention targeting a transdiagnostic factor, safety aids (cognitive or behavioral strategies used to cope with distress that paradoxically exacerbate symptoms). We conducted a randomized controlled trial to determine the acceptability and efficacy of this brief one-session intervention. Young adult undergraduates (N = 61) with elevated subclinical anxiety and insomnia were randomized to receive the anxiety-insomnia intervention or a physical health control condition. Participants were followed for 1 month and completed self-report measures. Analyses indicated that participants found the intervention acceptable, credible, and engaging. Analyses revealed the active intervention reduced sleep- and anxiety-related safety aids, with medium to large effect sizes. Findings suggest that targeting safety aids for anxiety and insomnia is acceptable and effective in reducing the target mechanism, safety aids, as well as worry. Future research should replicate these findings within a clinical sample and with a longer-term follow-up.

Sleep disturbance in PTSD and other anxiety-related disorders: an updated review of clinical features, physiological characteristics, and psychological and neurobiological mechanisms

The current report provides an updated review of sleep disturbance in posttraumatic stress disorder and anxiety-related disorders. First, this review provides a summary description of the unique and overlapping clinical characteristics and physiological features of sleep disturbance in specific DSM anxiety-related disorders. Second, this review presents evidence of a bidirectional relationship between sleep disturbance and anxiety-related disorders, and provides a model to explain this relationship by integrating research on psychological and neurocognitive processes with a current understanding of neurobiological pathways. A heuristic neurobiological framework for understanding the bidirectional relationship between abnormalities in sleep and anxiety-related brain pathways is presented. Directions for future research are suggested.

Sleep-Related Problems in Pediatric Obsessive-Compulsive Disorder and Intensive Exposure Therapy

Limited research has examined sleep-related problems (SRPs) among children and adolescents with obsessive-compulsive disorder (OCD). The present study addresses this gap by investigating preliminary associations between SRPs, demographic factors (gender and age), family variables (family accommodation and parental stress), and clinical factors (medication status, internalizing and externalizing symptoms, OCD severity, OCD-related impairment), and treatment outcomes in a sample of 103 youth (aged 7 to 17 years; 53% female) with a primary diagnosis of OCD. Clinician, parent, and child measures were used to assess demographic, family, and clinical predictors. SRPs were assessed using an 8-item measure comprising items of the Child Behaviour Checklist, Child Depression Inventory, and Multidimensional Anxiety Scale for Children as used in previous studies. Results showed that SRPs were highly prevalent among this sample and that more SRPs were associated with younger age, internalizing problems, and functional impairment. However, SRPs were not an independent predictor of OCD severity, impairment, or treatment response. Preliminary findings suggest that SRPs among youth with OCD may be more strongly associated with broader internalizing symptoms than with OCD itself. Future longitudinal research is warranted to further explore the complexity of SRPs when co-occurring with pediatric OCD.

Pre- to post-inpatient treatment of subjective sleep quality in 5,481 patients with mental disorders: A longitudinal analysis

There is only limited evidence of the course of sleep quality and sleep disturbances during acute inpatient treatment and the prediction of/association with treatment outcome in mental disorders. Within this naturalistic study, 5,481 consecutively admitted inpatients completed the Pittsburgh Sleep Quality Index (PSQI) and the Beck Depression Inventory (BDI-II) at admission and at discharge. Treatment included both individual and group psychotherapy (but no specific interventions for sleep disturbances) and pharmacotherapy based on current national treatment guidelines. Correlation analyses, analyses of variance and linear models were calculated to analyse the datasets. The PSQI improved significantly (p < 0.001) from admission (mean score 9.51 [±4.11]) to discharge (mean score 8.08 [±4.20]) in all diagnostic subgroups. Despite this improvement, 47% of the patients still showed elevated PSQI scores (>5) at discharge. Patients with post-traumatic stress disorder showed the largest sleep disturbances at both time-points; patients with obsessive-compulsive disorder were the least impaired. An improvement of the PSQI was found to be significantly correlated (p < 0.001) to the change of BDI-II values (without the sleep item) during treatment. The likelihood of achieving remission of depressive symptoms (BDI-II total score <14) was significantly associated with less sleep disturbances at admission. The results suggest that almost half of inpatients with mental disorders treated successfully with state-of-the art specific psychotherapy and pharmacotherapy do not have remission of their sleep problems. Therefore, specific treatment programmes for insomnia should be evaluated and implemented in daily clinical routines.

Electrophysiology of obsessive compulsive disorder: A systematic review of the electroencephalographic literature

Obsessive-compulsive disorder (OCD) is a chronic disease that causes significant decline in the quality of life of those affected. Due to our limited understanding of the underlying pathophysiology of OCD, successful treatment remains elusive. Although many have studied the pathophysiology of OCD through electroencephalography (EEG), limited attempts have been made to synthesize and interpret their findings. To bridge this gap, we conducted a comprehensive literature review using Medline/PubMed and considered the 65 most relevant studies published before June 2018. The findings are categorised into quantitative EEG, sleep related EEG and event related potentials (ERPs). Increased frontal asymmetry, frontal slowing and an enhancement in the ERP known as error related negativity (ERN) were consistent findings in OCD. However, sleep EEG and other ERP (P3 and N2) findings were inconsistent. Additionally, we analysed the usefulness of ERN as a potential candidate endophenotype. We hypothesize that dysfunctional frontal circuitry and overactive performance monitoring are the major underlying impairments in OCD. Additionally, we conceptualized that defective fronto-striato-thalamic circuitry causing poor cerebral functional connectivity gives rise to the OCD behavioural manifestations. Finally, we have discussed transcranial magnetic stimulation and EEG (TMS-EEG) applications in future research to further our knowledge of the underlying pathophysiology of OCD.

The role of eveningness in obsessive-compulsive symptoms: Cross-sectional and prospective approaches

BACKGROUND

Eveningness may be defined as the tendency to be most active and alert during the evening. Previous research has linked eveningness with maladaptive psychological outcomes, and recent evidence has highlighted circadian dysregulation as a novel factor in psychopathology, including obsessive-compulsive disorder (OCD). However, limited research has examined the unique relationship between eveningness and OC symptoms. Two studies were conducted to thoroughly examine the links between eveningness and OC symptoms, while also considering the role of depression symptoms and sleep-related factors.

METHODS

Using a cross-sectional approach, Study 1 examined the association between eveningness and OC symptoms when controlling for depression symptoms. Study 2 then employed a prospective approach to examine the extent to which the relationship between eveningness and change in OC symptoms over 4 months is mediated by change in sleep disturbance and total sleep time when controlling for depression symptoms.

RESULTS

Results indicated that depression better accounts for the cross-sectional association between eveningness and OC symptoms. However, eveningness was found to be a more robust prospective predictor of change in OC symptoms in Study 2. Furthermore, sleep disturbance, but not total sleep time, partially mediated the relationship between eveningness and OC symptoms.

LIMITATIONS

Single-method self-report approach, unselected sample, and lack of experimental manipulation.

CONCLUSIONS

These findings suggest that eveningness may contribute to the development of OC symptoms over time, in part due to its effect on sleep disturbance. Future research examining the role of circadian dysregulation in OCD may uncover novel physiological mechanisms.

Sleep disturbances in treatment-seeking OCD-patients: Changes after concentrated exposure treatment

Research indicates that patients with Obsessive Compulsive Disorder (OCD) frequently suffer from comorbid sleep difficulties, and that these difficulties often are not clinically recognized and diagnosed. There has been limited research investigating if comorbid sleep difficulties impair treatment outcome for OCD and if the sleep difficulties change following OCD-treatment. Thirty-six patients with obsessive compulsive disorder underwent concentrated exposure treatment delivered in a group over four consecutive days and were assessed with measures of OCD, depressive symptoms and sleep disturbance at three different time points (pre, post and 6 months follow-up). The sample was characterized by a high degree of comorbidity with other psychiatric disorders. At pre-treatment nearly 70% of the patients reported sleep difficulties indicative of primary insomnia. The results showed that patients had large reductions of OCD-symptoms as well as significant improvements in sleep disturbance assessed after treatment, and that these improvements were maintained at follow-up. Sleep disturbance did not impair treatment outcome, on the contrary patients with higher degree of sleep disturbance at pre-treatment had better outcome on OCD-symptoms after treatment. The results indicated that the majority of the OCD sample suffered from sleep disturbances and that these sleep disturbances were significantly reduced following adequate treatment of OCD without specific sleep interventions. However, a proportion of the patients suffered from residual symptoms of insomnia after treatment.

EEG-arousal regulation as predictor of treatment response in patients suffering from obsessive compulsive disorder

OBJECTIVES

Aim of this study was to analyze whether electroencephalogram (EEG)-based CNS-arousal markers differ for patients suffering from obsessive compulsive disorder (OCD) that either respond or do not respond to cognitive behavioral therapy (CBT), selective serotonin reuptake inhibitors (SSRIs) or their combination. Further the study aimed to identify specific response-predictors for the different therapy approaches.

METHODS

CNS-arousal from 51 unmedicated patients during fifteen-minute resting state was assessed using VIGALL (Vigilance Algorithm Leipzig). Clinical Global Impression (CGI) scores were used to assess response or non-response after three to six months following therapy (CBT, n=18; SSRI, n=11 or combination, n=22). Differences between Responders (R) and Non-Responders (NR) were identified using multivariate analysis of covariance (MANCOVA) models.

RESULTS

MANCOVA revealed that Responders spent significant less time at the highest CNS-arousal stage 0. Further, low amounts of the highest CNS-arousal stages were specifically predictive for a response to a combined treatment approach.

CONCLUSIONS

The fact that CNS-arousal markers allowed discrimination between Responders and Non-Responders and also between Responders of different treatment arms underlines a possible clinical value of EEG-based markers.

SIGNIFICANCE

These results encourage further research on EEG-arousal regulation for determining pathophysiological subgroups for treatment response.

Sleep disturbances in obsessive-compulsive disorder: Association with non-response to repetitive transcranial magnetic stimulation (rTMS)

Background Repetitive transcranial magnetic stimulation (rTMS) is a promising augmentation strategy for treatment-refractory OCD. However, a substantial group still fails to respond. Sleep disorders, e.g. circadian rhythm sleep disorders (CRSD), are highly prevalent in OCD and might mediate treatment response. The aims of the current study were to compare sleep disturbances between OCD patients and healthy subjects as well as between rTMS responders and non-responders, and most importantly to determine sleep-related predictors of rTMS non-response. Methods 22 OCD patients received at least 10 sessions rTMS combined with psychotherapy. Sleep disturbances were measured using questionnaires and actigraphy. Sleep in patients was compared to healthy subjects. Treatment response was defined as >35% reduction on YBOCS. Treatment response prediction models were based on measures of CRSD and insomnia. Results Sleep disturbances were more prevalent in OCD patients than healthy subjects. The OCD group consisted of 12 responders and 10 non-responders. The CRSD model could accurately predict non-response with 83% sensitivity and 63% specificity, whereas the insomnia model could not. Conclusions CRSD is more prevalent in OCD patients than healthy subjects, specifically in rTMS non-responders. Therefore, CRSD may serve as a biomarker for different subtypes of OCD corresponding with response to specific treatment approaches.

Sleep and mental disorders: A meta-analysis of polysomnographic research

Investigating sleep in mental disorders has the potential to reveal both disorder-specific and transdiagnostic psychophysiological mechanisms. This meta-analysis aimed at determining the polysomnographic (PSG) characteristics of several mental disorders. Relevant studies were searched through standard strategies. Controlled PSG studies evaluating sleep in affective, anxiety, eating, pervasive developmental, borderline and antisocial personality disorders, attention-deficit-hyperactivity disorder (ADHD), and schizophrenia were included. PSG variables of sleep continuity, depth, and architecture, as well as rapid-eye movement (REM) sleep were considered. Calculations were performed with the "Comprehensive Meta-Analysis" and "R" software. Using random effects modeling, for each disorder and each variable, a separate meta-analysis was conducted if at least 3 studies were available for calculation of effect sizes as standardized means (Hedges' g). Sources of variability, that is, sex, age, and mental disorders comorbidity, were evaluated in subgroup analyses. Sleep alterations were evidenced in all disorders, with the exception of ADHD and seasonal affective disorders. Sleep continuity problems were observed in most mental disorders. Sleep depth and REM pressure alterations were associated with affective, anxiety, autism and schizophrenia disorders. Comorbidity was associated with enhanced REM sleep pressure and more inhibition of sleep depth. No sleep parameter was exclusively altered in 1 condition; however, no 2 conditions shared the same PSG profile. Sleep continuity disturbances imply a transdiagnostic imbalance in the arousal system likely representing a basic dimension of mental health. Sleep depth and REM variables might play a key role in psychiatric comorbidity processes. Constellations of sleep alterations may define distinct disorders better than alterations in 1 single variable. (PsycINFO Database Record

Sleep disturbance and obsessive-compulsive symptoms: Results from the national comorbidity survey replication

A small body of developing research has found evidence for sleep disturbance in obsessive-compulsive disorder (OCD) and links between sleep disturbance and obsessive-compulsive symptoms (OCS) in unselected samples. However, the link between sleep disturbance and OCS is yet to be examined in a nationally representative sample. Furthermore, the extent to which the link between sleep disturbance and OCS is accounted for by symptoms of depression remains unclear. To address this gap in the literature, the present study examined the relationship between sleep disturbance and OCS in a nationally representative sample. Participants were assessed in the National Comorbidity Survey Replication (NCS-R; n = 2073). Consistent with predictions, results revealed that individuals with sleep disturbance reported increased OCS severity compared to individuals without sleep disturbance. Further, sleep disturbance severity was associated with OCS severity, even when controlling for depression (and other anxiety-related disorders). This study is the first to link sleep disturbance and OCS in a nationally representative sample, and these findings highlight the unique role of sleep disturbance in the experience of OCS. Future research is necessary to delineate specific mechanisms that may account for this relationship.

Influence of Tryptophan and Serotonin on Mood and Cognition with a Possible Role of the Gut-Brain Axis

The serotonergic system forms a diffuse network within the central nervous system and plays a significant role in the regulation of mood and cognition. Manipulation of tryptophan levels, acutely or chronically, by depletion or supplementation, is an experimental procedure for modifying peripheral and central serotonin levels. These studies have allowed us to establish the role of serotonin in higher order brain function in both preclinical and clinical situations and have precipitated the finding that low brain serotonin levels are associated with poor memory and depressed mood. The gut-brain axis is a bi-directional system between the brain and gastrointestinal tract, linking emotional and cognitive centres of the brain with peripheral functioning of the digestive tract. An influence of gut microbiota on behaviour is becoming increasingly evident, as is the extension to tryptophan and serotonin, producing a possibility that alterations in the gut may be important in the pathophysiology of human central nervous system disorders. In this review we will discuss the effect of manipulating tryptophan on mood and cognition, and discuss a possible influence of the gut-brain axis.

A systematic review of sleep disturbance in anxiety and related disorders

Recent research suggests that sleep disturbance may be a transdiagnostic process, and there is increasing interest in examining how sleep disturbance may contribute to anxiety and related disorders. The current review summarizes and synthesizes the extant research assessing sleep in anxiety and related disorders. The findings suggest that sleep disturbance exacerbates symptom severity in the majority of anxiety and related disorders. However, the nature of sleep disturbance often varies as a function of objective versus subjective assessment. Although sleep disturbance is a correlate of most anxiety and related disorders, a causal role for sleep disturbance is less clear. A model of potential mechanisms by which sleep disturbance may confer risk for the development of anxiety and related disorders is discussed. Future research integrating findings from basic sleep research with current knowledge of anxiety and related disorders may facilitate the development of novel treatments for comorbid sleep disturbance and clinical anxiety.

Recent Advances in the Study of Sleep in the Anxiety Disorders, Obsessive-Compulsive Disorder, and Posttraumatic Stress Disorder

Sleep disturbance is frequently associated with generalized anxiety disorder, panic disorder, obsessive-compulsive disorder, and posttraumatic stress disorder. This article reviews recent advances in understanding the mechanisms of the sleep disturbances in these disorders and discusses the implications for developing improved treatments.

Obsessive-compulsive symptom dimensions and insomnia: The mediating role of anxiety sensitivity cognitive concerns

Existing research on the relationship between obsessive-compulsive disorder (OCD) and insomnia is scarce. Moreover, no research has examined potential mechanisms that may account for the observed relations among OCD and sleep difficulties. The cognitive concerns subscale of anxiety sensitivity (AS), which reflects fears of mental incapacitation, has been linked to both symptoms of OCD and insomnia and may serve as a mechanism for increasing sleep disturbance among patients with OCD. The current study examined the relationship between OCD symptoms and insomnia and the potential mediating role of AS cognitive concerns. The sample consisted of 526 individuals recruited through Amazon's Mechanical Turk (Mturk), an online crowdsourcing marketplace. Results revealed distinct associations between the unacceptable thoughts domain of OCD and symptoms of insomnia. Additionally, AS cognitive concerns mediated the relationship between these constructs. Future research should seek to replicate these findings using clinical samples and prospective designs.

Sleep, arousal, and circadian rhythms in adults with obsessive-compulsive disorder: a meta-analysis

Findings of this meta-analysis show that obsessive-compulsive disorder (OCD) is related to disruptions in both the duration and timing of sleep. PsycINFO and Google Scholar database searches identified 12 relevant studies that compared measures of sleep in individuals with OCD to those of either a healthy control group or published norms. Sleep measures included sleep onset latency, sleep duration, awakening after sleep onset, percentage of rapid eye movement (REM) sleep, percentage of slow wave sleep, and prevalence of delayed sleep phase disorder (DSPD). Individual effect sizes were pooled using a random effects model. Sleep duration was found to be shorter, and the prevalence of DSPD higher, in individuals with OCD compared to controls. Further, excluding samples with comorbid depression did not meaningfully reduce the magnitude of these effects (although the results were no longer statistically significant) and medication use by participants is unlikely to have systematically altered sleep timing. Overall, available data suggest that sleep disruption is associated with OCD but further research on both sleep duration and sleep timing in individuals with OCD is needed.

Obsessive-compulsive symptoms and characteristics in individuals with delayed sleep phase disorder

Research has demonstrated a relationship between circadian disruption and severe obsessive-compulsive disorder (OCD). Misalignment of sleep timing/endogenous biological rhythms with the 24-hour light/dark cycle may result in difficulty dismissing intrusive thoughts, thus increasing vulnerability to disorders characterized by intrusive thoughts, such as OCD. Deficits in inhibition of intrusive thoughts are posited to play a role in OCD. The current study investigated whether individuals with delayed sleep phase disorder (DSPD) report elevated symptoms of OCD and have greater difficulty inhibiting intrusive thoughts than do individuals without DSPD. Community participants with and without DSPD completed questionnaires and performed behavioral tasks designed to elicit intrusive thoughts. The participants with DSPD (n = 27) had elevated OCD symptoms and greater rates of disorders characterized by intrusive thoughts on a structured interview, as compared with the participants without DSPD (n = 19). These results support a link between the timing of sleep and symptoms of OCD. Implications and future directions are discussed.

Sleep and obsessive-compulsive disorder (OCD)

Obsessive-compulsive disorder (OCD) is a chronic mental illness that can have a debilitating effect on daily functioning. A body of research reveals altered sleep behaviour in OCD sufferers; however, findings are inconsistent and there is no consensus on the nature of this relationship. Understanding sleep disturbance in OCD is of critical importance given the known negative consequences of disturbed sleep for mood and emotional wellbeing. A systematic literature search was conducted of five databases for studies assessing sleep in adults diagnosed with OCD. Fourteen studies met inclusion criteria and qualitative data analysis methods were used to identify common themes. There was some evidence of reduced total sleep time and sleep efficiency in OCD patients. Many of the sleep disturbances noted were characteristic of depression. However, some OCD sufferers displayed delayed sleep onset and offset and an increased prevalence of delayed sleep phase disorder (DSPD). Severe OCD symptoms were consistently associated with greater sleep disturbance. While the sleep of OCD patients has not been a major focus to date, the existing literature suggests that addressing sleep disturbance in OCD patients may ensure a holistic approach to treatment, enhance treatment efficacy, mitigate relapse and protect against the onset of co-morbid psychiatric illnesses.

How should we measure delayed sleep phase shift in severe, refractory obsessive-compulsive disorder?

OBJECTIVE

A previous study, based upon direct nursing observations, showed almost half of a cohort of inpatients with severe, enduring OCD also suffered from delayed sleep phase shift. Males, younger patients and those with more severe symptoms were most likely to be affected. However, the ward environment may have had a direct effect on sleeping patterns. In this study we compared the accuracy of actigraphic measurements with that of the "gold standard" of direct nursing observation, and other clinical sleep scales. We postulated that actigraphy would prove a reliable, acceptable, and valid alternative.

METHODS

All patients admitted over 29 months to a specialized treatment unit for severe, chronic refractory OCD were invited to participate. We collected demographic data, clinical measures of OCD and depressive symptom severity, self-rated measures of social and occupational disability and sleep, nursing records based upon direct observation of sleep onset and duration, and actigraphy records.

RESULTS

Evaluable data was obtained from 36 patients (22 males) with an average age of 37 years and profound OCD symptoms measured by the Yale-Brown Obsessive-Compulsive Scale. According to direct nursing observation, 12 patients (33%) showed delayed sleep phase shift. Actigraphic recordings demonstrated good agreement (kappa = 0.63) with nursing observation as did the St George's Insomnia Questionnaire (kappa = 0.66).

CONCLUSION

This study demonstrates that actigraphy is a reliable method of recording sleep/activity cycles in severe, enduring OCD.

Sleep and its importance in adolescence and in common adolescent somatic and psychiatric conditions

Restoring sleep is strongly associated with a better physical, cognitive, and psychological well-being. By contrast, poor or disordered sleep is related to impairment of cognitive and psychological functioning and worsened physical health. These associations are well documented not only in adults but also in children and adolescents. Importantly, adolescence is hallmarked by dramatic maturational changes in sleep and its neurobiological regulation, hormonal status, and many psychosocial and physical processes. Thus, the role of sleep in mental and physical health during adolescence and in adolescent patients is complex. However, it has so far received little attention. This review first presents contemporary views about the complex neurobiology of sleep and its functions with important implications for adolescence. Second, existing complex relationships between common adolescent somatic/organic, sleep-related, and psychiatric disorders and certain sleep alterations are discussed. It is concluded that poor or altered sleep in adolescent patients may trigger and maintain many psychiatric and physical disorders or combinations of these conditions, which presumably hinder recovery and may cross into later stages of life. Therefore, timely diagnosis and management of sleep problems appear critical for growth and development in adolescent patients.

The relation between sleep and pain among a non-clinical sample of young adults

Poor sleep is linked to poorer daily functioning and increased risk of psychiatric symptoms. With respect to pain, the relation is bi-directional; poor sleep exacerbates pain, while greater pain adversely affects sleep. Moreover, perception of pain is subject to cognitive-emotional processes. Surprisingly, no data are available from non-clinical samples of young adults. The aim of the present study was therefore to investigate the relation between sleep and pain as a function of quality of life and depressive symptoms in young adults. The direction of influence between sleep and pain was statistically tested with two different structural equation models (SEMs). A total of 862 participants (639 women, 223 men; mean age: 24.67; SD = 5.91) completed a series of validated self-report questionnaires assessing sleep, quality of life, depressive symptoms and cognitive-emotional elaboration of pain. Sleep, pain, quality of life, and depressive symptoms were interrelated. The first SEM suggested both a direct and an indirect influence of pain on sleep, whereas the second SEM suggested that sleep had only an indirect influence on pain. Irrespective of the SEM, the relation between sleep and cognitive-emotional elaboration of pain was mediated by quality of life and depressive symptoms. For a non-clinical sample of young adults, findings did support the bi-directional relation between poor sleep and increased cognitive-emotional elaboration of pain, though other cognitive-emotional processes such as depressive symptoms and quality of life should be taken into account.

Dream recall and dream content in obsessive-compulsive patients: is there a change during exposure treatment?

Very little is known about dreams in patients with obsessive compulsive disorder, especially regarding changes over the course of treatment with stimulus exposure and response prevention. By use of dream content analysis, 40 dreams of 9 obsessive compulsive (OC) inpatients were compared with 84 dreams of 10 matched OC outpatients and 63 dreams of 11 healthy control participants. Dream protocols of inpatients were collected at the beginning of treatment and after the first exposure exercises. Controls filled in dream protocols in respective intervals. Before treatment, dreams of patients showed significantly less positive contents than dreams of healthy controls. Under treatment with exposure, a significant reduction of OC themes was observed. The findings support the continuity hypothesis of dreaming by showing a link between day-time symptoms and OC symptoms in dreams. Contrary to expectations, however, exposure treatment does not intensify dreams.

[Disturbances of slow-wave sleep and psychiatric disorders]

Slow-wave sleep is defined as sleep stages 3 and 4 that characteristically show slow delta EEG activity during polysomnography. The percentage of slow-wave sleep normally declines with age. Sleep disorders are a common symptom of many psychiatric disorders. In polysomnographic recordings they mostly manifest as disturbances of sleep continuity. In some disorders changes in REM sleep are also found. A reduction of slow-wave sleep has most often been described in patients with depression and addictive disorders. More recent research implicates slow-wave sleep as an important factor in memory consolidation, especially the contents of declarative memory. Psychotropic drugs influence sleep in different ways. Hypnotic substances can reduce the deep sleep stages (e.g. benzodiazepines), whereas 5-HT2C antagonists increase the percentage of slow-wave sleep. Whether a selective impairment/alteration of slow-wave sleep is clinically relevant has not yet been proved.

Lack of association between MAGEL2 and schizophrenia and mood disorders in the Japanese population

Several investigations have reported that abnormalities in circadian rhythms might be related with the pathophysiology of psychiatric disorders, since many psychiatric patients have insomnia and sleep-awake disturbance. A recent animal study reported that Magel2, which encodes a member of the MAGE/necdin family of proteins, might be associated in the pathophysiology of psychiatric disorders. Magel2 gene knockout mice showed altered concentrations of both dopamine and serotonin in several parts of the brain compared with controls. In addition, the authors of that study detected a bilateral reduction in cortical volume in distinct regions of the Magel2 gene knockout mice brain, including focused regions in the parieto-temporal lobe of the cerebral cortex, the amygdala, the hippocampus, and the nucleus accumbens. These mice were also found to have hypoactivity and abnormalities in circadian rhythms. From this evidence, we considered Magel2 gene (MAGEL2) to be a good candidate gene for the pathophysiology of schizophrenia and mood disorder, and we conducted a case-control study among Japanese (731 schizophrenia patients, 465 MDD patients, 156 BP patients and 758 controls) using three tagging SNPs in MAGEL2 (rs850815, rs8920 and rs4480754), selected using the HapMap database. We did not find any association between MAGEL2 and schizophrenia, BP or MDD in allele/genotype-wise analysis or haplotype-wise analysis. Our results suggest that MAGEL2 may not play a role in the pathophysiology of schizophrenia and mood disorders in the Japanese population. A replication study using larger samples may be required for conclusive results, since our sample size was small and our study analyzed only three SNPs in MAGEL2.

Association study of clock gene (CLOCK) and schizophrenia and mood disorders in the Japanese population

Recently the clock genes have been reported to play some roles in neural transmitter systems, including the dopamine system, as well as to regulate circadian rhythms. Abnormalities in both of these mechanisms are thought to be involved in the pathophysiology of major mental illness such as schizophrenia and mood disorders including bipolar disorder (BP) and major depressive disorder (MDD). Recent genetic studies have reported that CLOCK, one of the clock genes, is associated with these psychiatric disorders. Therefore, we investigated the association between the six tagging SNPs in CLOCK and the risk of these psychiatric disorders in Japanese patients diagnosed with schizophrenia (733 patients), BP (149) and MDD (324), plus 795 Japanese controls. Only one association, with schizophrenia in females, was detected in the haplotype analysis (P = 0.0362). However, this significance did not remain after Bonferroni correction (P = 0.0724). No significant association was found with BP and MDD. In conclusion, we suggest that CLOCK may not play a major role in the pathophysiology of Japanese schizophrenia, BP and MDD patients. However, it will be important to replicate and confirm these findings in other independent studies using large samples.

Co-occurrence of Insomnia and Anxiety Disorders: A Review of the Literature

Insomnia and anxiety disorders are highly prevalent and are associated with significant impairment and disability. There is evidence that insomnia and anxiety disorders commonly co-occur, in addition to both being highly comorbid with major depressive disorder. Thus, it is important for health care providers to be familiar with the literature in this area. Therefore, the purpose of this review was to examine the empirical literature on the co-occurrence of insomnia and anxiety disorders, as well as discuss the clinical and research implications of the findings. Studies were identified through PubMed and PsycINFO searches (1975-2007) and a bibliographic review of published articles. The results from this literature review suggest that certain anxiety disorders, such as panic disorder and generalized anxiety disorder, are clearly associated with symptoms of insomnia (eg, delayed sleep onset, restless sleep). Although there are some discrepancies in the literature, the findings suggest that individuals with posttraumatic stress disorder also experience significant sleep problems (eg, middle-of-the-night insomnia, poor sleep quality, nightmares), and the presence of such problems during the early posttrauma period predicts later development of the disorder. Few empirical studies examine sleep in other anxiety disorders, and the majority of studies on insomnia and anxiety disorders in general have not examined the effects of comorbid major depressive disorder, indicating a need for additional research. Overall, the findings highlight the importance of screening for and treating anxiety symptoms when a patient presents with symptoms of insomnia and vice versa. Clearly, treatment development work on interventions that address co-occurring insomnia and anxiety disorders is greatly needed.

EEG-vigilance differences between patients with borderline personality disorder, patients with obsessive-compulsive disorder and healthy controls

The regulation of brain activation, as assessed with the EEG, is a state modulated trait. A decline to lowered EEG-vigilance states has been found to be associated with emotional instability in older studies, but has not been systematically studied in patients with borderline personality disorder (BPD). Twenty unmedicated BPD patients were compared to 20 unmedicated patients with obsessive-compulsive disorder (OCD) as well as 20 healthy controls concerning their EEG-vigilance regulation over a 5-min period assessed with an algorithm classifying every artefact-free 2-s EEG segment into the EEG-vigilance state (A1-A3, B (=non-A)). If the alpha power was posterior more than 55% of the whole alpha power (anterior + posterior) in the artefact-free EEG-segments, that segment was marked as A1, if it was anterior more than 55% of the whole alpha power, as A3. For A2 the following rule was defined: Posterior or anterior alpha between 50 and 55% of the whole alpha power.BPD patients showed significantly lower rates of EEG-vigilance state A compared to OCD patients, indicating a lowered EEG-vigilance. All three groups showed a decrease in the rate of EEG-vigilance state A over the 5 min recording period in line with a lowering of vigilance. The study provides evidence for a less stable regulation of EEG-vigilance in BPD compared to OCD patients and is in line with concepts postulating that the behavioural pattern with sensation seeking and impulsivity in BPD has a compensatory and autoregulatory function to stabilize activation of the CNS.

Effect of illicit recreational drugs upon sleep: cocaine, ecstasy and marijuana

The illicit recreational drugs cocaine, ecstasy and marijuana have pronounced effects upon sleep. Administration of cocaine increases wakefulness and suppresses REM sleep. Acute cocaine withdrawal is often associated with sleep disturbances and unpleasant dreams. Studies have revealed that polysomnographically assessed sleep parameters deteriorate even further during sustained abstinence, although patients report that sleep quality remains unchanged or improves. This deterioration of objective sleep measures is associated with a worsening in sleep-related cognitive performance. Like cocaine, 3,4-methylenedioxymethamphetamine (MDMA; "ecstasy") is a substance with arousing properties. Heavy MDMA consumption is often associated with persistent sleep disturbances. Polysomnography (PSG) studies have demonstrated altered sleep architecture in abstinent heavy MDMA users. Smoked marijuana and oral Delta-9-tetrahydrocannabinol (THC) reduce REM sleep. Moreover, acute administration of cannabis appears to facilitate falling asleep and to increase Stage 4 sleep. Difficulty sleeping and strange dreams are among the most consistently reported symptoms of acute and subacute cannabis withdrawal. Longer sleep onset latency, reduced slow wave sleep and a REM rebound can be observed. Prospective studies are needed in order to verify whether sleep disturbances during cocaine and cannabis withdrawal predict treatment outcome.

Sleep-related problems in pediatric obsessive-compulsive disorder

Although attention has been given to presence of sleep related problems (SRPs) in children with psychiatric conditions, little has been reported on SRPs in youth with obsessive-compulsive disorder (OCD). Sixty-six children and adolescents with OCD were administered the Children's Yale Brown Obsessive-Compulsive Scale and completed the Children's Depression Inventory and Multidimensional Anxiety Scale. Their parents completed the Child Behavior Checklist and Children's Obsessive-Compulsive Impact Scale. A subset of youth (n=41) completed a trial of cognitive-behavioral therapy. Frequency of eight specific SRPs was examined in relation to age, gender, OCD symptom severity, child-rated symptoms of depression and anxiety, parent-proxy ratings of internalizing and externalizing problems, and functional impairment. Ninety-two percent of youth experienced at least one SRP, with 27.3% reporting five or more SRPs. Total SRPs were positively associated with OCD symptom severity, child-rated anxiety, and parent-proxy ratings of internalizing problems. Total and several specific SRPs were reduced following cognitive-behavioral treatment. These results suggest that SRPs are relatively common in youth with OCD, are associated with symptom severity, and warrant attention during assessment and treatment.