Aerobic physical exercise as a possible treatment for neurocognitive dysfunction in bipolar disorder

Factors that influence participation in physical activity for people with bipolar disorder: a synthesis of qualitative evidence

BACKGROUND

Mental health problems contribute significantly to the overall disease burden worldwide and are major causes of disability, suicide, and ischaemic heart disease. People with bipolar disorder report lower levels of physical activity than the general population, and are at greater risk of chronic health conditions including cardiovascular disease and obesity. These contribute to poor health outcomes. Physical activity has the potential to improve quality of life and physical and mental well-being.

OBJECTIVES

To identify the factors that influence participation in physical activity for people diagnosed with bipolar disorder from the perspectives of service users, carers, service providers, and practitioners to help inform the design and implementation of interventions that promote physical activity.

SEARCH METHODS

We searched MEDLINE, PsycINFO, and eight other databases to March 2021. We also contacted experts in the field, searched the grey literature, and carried out reference checking and citation searching to identify additional studies. There were no language restrictions.

SELECTION CRITERIA

We included qualitative studies and mixed-methods studies with an identifiable qualitative component. We included studies that focused on the experiences and attitudes of service users, carers, service providers, and healthcare professionals towards physical activity for bipolar disorder.

DATA COLLECTION AND ANALYSIS

We extracted data using a data extraction form designed for this review. We assessed methodological limitations using a list of predefined questions. We used the "best fit" framework synthesis based on a revised version of the Health Belief Model to analyse and present the evidence. We assessed methodological limitations using the CASP Qualitative Checklist. We used the GRADE-CERQual (Confidence in the Evidence from Reviews of Qualitative research) guidance to assess our confidence in each finding. We examined each finding to identify factors to inform the practice of health and care professionals and the design and development of physical activity interventions for people with bipolar disorder.

MAIN RESULTS

We included 12 studies involving a total of 592 participants (422 participants who contributed qualitative data to an online survey, 170 participants in qualitative research studies). Most studies explored the views and experiences of physical activity of people with experience of bipolar disorder. A number of studies also reported on personal experiences of physical activity components of lifestyle interventions. One study included views from family carers and clinicians. The majority of studies were from high-income countries, with only one study conducted in a middle-income country. Most participants were described as stable and had been living with a diagnosis of bipolar disorder for a number of years. We downgraded our confidence in several of the findings from high confidence to moderate or low confidence, as some findings were based on only small amounts of data, and the findings were based on studies from only a few countries, questioning the relevance of these findings to other settings. We also had very few perspectives of family members, other carers, or health professionals supporting people with bipolar disorder. The studies did not include any findings from service providers about their perspectives on supporting this aspect of care. There were a number of factors that limited people's ability to undertake physical activity. Shame and stigma about one's physical appearance and mental health diagnosis were discussed. Some people felt their sporting skills/competencies had been lost when they left school. Those who had been able to maintain exercise through the transition into adulthood appeared to be more likely to include physical activity in their regular routine. Physical health limits and comorbid health conditions limited activity. This included bipolar medication, being overweight, smoking, alcohol use, poor diet and sleep, and these barriers were linked to negative coping skills. Practical problems included affordability, accessibility, transport links, and the weather. Workplace or health schemes that offered discounts were viewed positively. The lack of opportunity for exercise within inpatient mental health settings was a problem. Facilitating factors included being psychologically stable and ready to adopt new lifestyle behaviours. There were positive benefits of being active outdoors and connecting with nature. Achieving balance, rhythm, and routine helped to support mood management. Fitting physical activity into a regular routine despite fluctuating mood or motivation appeared to be beneficial if practised at the right intensity and pace. Over- or under-exercising could be counterproductive and accelerate depressive or manic moods. Physical activity also helped to provide a structure to people's daily routines and could lead to other positive lifestyle benefits. Monitoring physical or other activities could be an effective way to identify potential triggers or early warning signs. Technology was helpful for some. People who had researched bipolar disorder and had developed a better understanding of the condition showed greater confidence in managing their care or providing care to others. Social support from friends/family or health professionals was an enabling factor, as was finding the right type of exercise, which for many people was walking. Other benefits included making social connections, weight loss, improved quality of life, and better mood regulation. Few people had been told of the benefits of physical activity. Better education and training of health professionals could support a more holistic approach to physical and mental well-being. Involving mental health professionals in the multidisciplinary delivery of physical activity interventions could be beneficial and improve care. Clear guidelines could help people to initiate and incorporate lifestyle changes.

AUTHORS' CONCLUSIONS

There is very little research focusing on factors that influence participation in physical activity in bipolar disorder. The studies we identified suggest that men and women with bipolar disorder face a range of obstacles and challenges to being active. The evidence also suggests that there are effective ways to promote managed physical activity. The research highlighted the important role that health and care settings, and professionals, can play in assessing individuals' physical health needs and how healthy lifestyles may be promoted. Based on these findings, we have provided a summary of key elements to consider for developing physical activity interventions for bipolar disorder.

Evaluating the effect of exercise-based interventions on functioning in people with transdiagnostic depressive symptoms: A systematic review of randomised controlled trials

BACKGROUND

Depressive symptoms are associated with various conditions and can exacerbate the outcome of somatic diseases. Transdiagnostic symptom-based approaches provide treatment flexibility, and exercise has demonstrated benefits beyond clinical symptoms. This work aimed to synthesise and establish the effects of exercise-based interventions on global functioning and quality of life in adults with transdiagnostic depressive symptoms, as well as their impact on clinical symptoms.

METHODS

A systematic review was conducted following PRISMA guidelines. PubMed, Scopus and PsycINFO databases were searched from inception to April 2023. Eligibility criteria included randomised controlled trials involving adults with transdiagnostic depressive symptoms who received exercise-based interventions and provided details of the interventions. Comparators included treatment as usual or other active control groups. The Cochrane quality assessment tool was used for quality assessment.

RESULTS

Fifteen articles involving 2064 participants were included. Data on study design, sample, intervention characteristics, and outcomes were extracted. Several trials demonstrated the expected positive effects of exercise on functioning (7/15). Most results supported the benefits of adjunctive exercise interventions on illness outcomes.

LIMITATIONS

The studies had methodological limitations, including small sample sizes and an underrepresentation of somatic diseases.

CONCLUSIONS

The functional consequences of exercise-based interventions targeting depressive symptoms are often understudied. Incorporating exercise routinely as an add-on treatment for transdiagnostic depressive symptoms could improve overall functioning, quality of life, and symptom severity. There is a need to expand the focus of exercise-based interventions to incorporate functional outcomes. Future research should address the methodological limitations and include a wider range of participants, including those with somatic diseases.

Efficacy of Functional Remediation on Cognitive and Psychosocial Functioning in Patients with Bipolar Disorder: Study Protocol for a Randomized Controlled Study

BACKGROUND

Neurocognitive impairment is a prominent characteristic of bipolar disorder (BD), linked with poor psychosocial functioning. This study's purpose is to evaluate the effectiveness of functional remediation (FR) in enhancing neurocognitive dysfunctions in a sample of remitted patients with diagnosis of BD in comparison to treatment as usual-TAU. To quantify the neurocognitive damage, the Brief Assessment of Cognition in Affective Disorders (BAC-A) will be used, and the overall psychosocial functioning will be measured with the Functioning Assessment Short Test-FAST.

METHODS

The randomized, rater-blinded, controlled study will include two arms (1:1) encompassing 54 outpatients with diagnosis of BD-I and BD-II, as defined by the DSM-5 criteria. In the experimental phase, remitted patients aged 18-55 years will be involved. At the baseline, at the end of intervention and at the 6-month follow-up, patients will be evaluated using clinical scales (Young Mania Rating Scale (Y-MRS) and Hamilton Depression Rating Scale (HAM-D)). Neurocognitive measurements and psychosocial functioning will be valued, respectively, with BAC-A and FAST.

DISCUSSION

The primary expected outcome is that following FR intervention, patients will exhibit improved cognitive abilities and psychosocial outcomes compared to the participants in the TAU group. It is now recognized that neurocognitive deficits are potential predictors of functional outcome in patients with BD. In recent years, there has been a growing interest in the implementation of interventions that, in addition to symptomatic remission, are also aimed at neurocognitive dysfunctions in order to achieve a recovery of psychosocial functioning.

The clinical characterization of the adult patient with bipolar disorder aimed at personalization of management

Bipolar disorder is heterogeneous in phenomenology, illness trajectory, and response to treatment. Despite evidence for the efficacy of multimodal-ity interventions, the majority of persons affected by this disorder do not achieve and sustain full syndromal recovery. It is eagerly anticipated that combining datasets across various information sources (e.g., hierarchical "multi-omic" measures, electronic health records), analyzed using advanced computational methods (e.g., machine learning), will inform future diagnosis and treatment selection. In the interim, identifying clinically meaningful subgroups of persons with the disorder having differential response to specific treatments at point-of-care is an empirical priority. This paper endeavours to synthesize salient domains in the clinical characterization of the adult patient with bipolar disorder, with the overarching aim to improve health outcomes by informing patient management and treatment considerations. Extant data indicate that characterizing select domains in bipolar disorder provides actionable information and guides shared decision making. For example, it is robustly established that the presence of mixed features - especially during depressive episodes - and of physical and psychiatric comorbidities informs illness trajectory, response to treatment, and suicide risk. In addition, early environmental exposures (e.g., sexual and physical abuse, emotional neglect) are highly associated with more complicated illness presentations, inviting the need for developmentally-oriented and integrated treatment approaches. There have been significant advances in validating subtypes of bipolar disorder (e.g., bipolar I vs. II disorder), particularly in regard to pharmacological interventions. As with other severe mental disorders, social functioning, interpersonal/family relationships and internalized stigma are domains highly relevant to relapse risk, health outcomes, and quality of life. The elevated standardized mortality ratio for completed suicide and suicidal behaviour in bipolar disorder invites the need for characterization of this domain in all patients. The framework of this paper is to describe all the above salient domains, providing a synthesis of extant literature and recommendations for decision support tools and clinical metrics that can be implemented at point-of-care.

The Role of Tryptophan Metabolites in Neuropsychiatric Disorders

In recent decades, neuropsychiatric disorders such as major depressive disorder, schizophrenia, bipolar, etc., have become a global health concern, causing various detrimental influences on patients. Tryptophan is an important amino acid that plays an indisputable role in several physiological processes, including neuronal function and immunity. Tryptophan’s metabolism process in the human body occurs using different pathways, including the kynurenine and serotonin pathways. Furthermore, other biologically active components, such as serotonin, melatonin, and niacin, are by-products of Tryptophan pathways. Current evidence suggests that a functional imbalance in the synthesis of Tryptophan metabolites causes the appearance of pathophysiologic mechanisms that leads to various neuropsychiatric diseases. This review summarizes the pharmacological influences of tryptophan and its metabolites on the development of neuropsychiatric disorders. In addition, tryptophan and its metabolites quantification following the neurotransmitters precursor are highlighted. Eventually, the efficiency of various biomarkers such as inflammatory, protein, electrophysiological, genetic, and proteomic biomarkers in the diagnosis/treatment of neuropsychiatric disorders was discussed to understand the biomarker application in the detection/treatment of various diseases.

Tryptophan Metabolism in Bipolar Disorder in a Longitudinal Setting

Immune-mediated inflammatory processes and oxidative stress are involved in the aetiopathogenesis of bipolar disorder (BD) and weight-associated comorbidities. Tryptophan breakdown via indoleamine 2,3-dioxygenase-1 (IDO-1) along the kynurenine axis concomitant with a pro-inflammatory state was found to be more active in BD, and associated with overweight/obesity. This study aimed to investigate tryptophan metabolism in BD compared to controls (C), stratified by weight classes, in a longitudinal setting, dependent on the incidence of BD episodes. Peripheral tryptophan, kynurenine, and neopterin were assessed in the serum of 226 BD individuals and 142 C. Three samples in a longitudinal assessment were used for 75 BD individuals. Results showed a higher kynurenine/tryptophan in both BD compared to C and overweight compared to normal weight persons. Levels remained stable over time. In the longitudinal course, no differences were found between individuals who were constantly euthymic or not, or who had an illness episode or had none. Findings indicate that tryptophan, kynurenine, and IDO-1 activity may play a role in pathophysiology in BD but are not necessarily associated with clinical manifestations. Accelerated tryptophan breakdown along the kynurenine axis may be facilitated by being overweight. This may increase the risk of accumulation of neurotoxic metabolites, impacting BD symptomatology, cognition, and somatic comorbidities.

Management of cognitive impairment in bipolar disorder: a systematic review of randomized controlled trials

Cognitive impairment is common in bipolar disorder and is emerging as a therapeutic target to enhance quality of life and function. A systematic search was conducted on PubMed, PsycInfo, Cochrane, clinicaltrials.gov, and Embase databases for blinded or open-label randomized controlled trials evaluating the pro-cognitive effects of pharmacological, neurostimulation, or psychological interventions for bipolar disorder. Twenty-two trials were identified, evaluating a total of 16 different pro-cognitive interventions. The methodological quality of the identified trials were assessed using the Cochrane Risk of Bias tool. Currently, no intervention (i.e., pharmacologic, neurostimulation, cognitive remediation) has demonstrated robust and independent pro-cognitive effects in adults with bipolar disorder. Findings are preliminary and methodological limitations limit the interpretation of results. Methodological considerations including, but not limited to, the enrichment with populations with pre-treatment cognitive impairment, as well as the inclusion of individuals who are in remission are encouraged. Future trials may also consider targeting interventions to specific cognitive subgroups and the use of biomarkers of cognitive function.

Prolonged functional cerebral asymmetry as a consequence of dysfunctional parvocellular paraventricular hypothalamic nucleus signaling: An integrative model for the pathophysiology of bipolar disorder

Approximately 45 million people worldwide are diagnosed with bipolar disorder (BD). While there are many known risk factors and models of the pathologic processes influencing BD, the exact neurologic underpinnings of BD are unknown. We attempt to integrate the existing literature and create a unifying hypothesis regarding the pathophysiology of BD with the hope that a concrete model may potentially facilitate more specific diagnosis, prevention, and treatment of BD in the future. We hypothesize that dysfunctional signaling from the parvocellular neurons of the paraventricular hypothalamic nucleus (PVN) results in the clinical presentation of BD. Functional damage to this nucleus and its signaling pathways may be mediated by myriad factors (e.g. immune dysregulation and auto-immune processes, polygenetic variation, dysfunctional interhemispheric connections, and impaired or overactivated hypothalamic axes) which could help explain the wide variety of clinical presentations along the BD spectrum. The neurons of the PVN regulate ultradian rhythms, which are observed in cyclic variations in healthy individuals, and mediate changes in functional hemispheric lateralization. Theoretically, dysfunctional PVN signaling results in prolonged functional hemispheric dominance. In this model, prolonged right hemispheric dominance leads to depressive symptoms, whereas left hemispheric dominance correlated to the clinical picture of mania. Subsequently, physiologic processes that increase signaling through the PVN (hypothalamic-pituitaryadrenal axis, hypothalamic- pituitary-gonadal axis, and hypothalamic-pituitary-thyroid axis activity, suprachiasmatic nucleus pathways) as well as, neuro-endocrine induced excito-toxicity, auto-immune and inflammatory flairs may induce mood episodes in susceptible individuals. Potentially, ultradian rhythms slowing with age, in combination with changes in hypothalamic axes and maturation of neural circuitry, accounts for BD clinically presenting more frequently in young adulthood than later in life.

Current understandings of the trajectory and emerging correlates of cognitive impairment in bipolar disorder: An overview of evidence

OBJECTIVES

Cognitive dysfunction affects a significant proportion of people with bipolar disorder (BD), but the cause, trajectory and correlates of such dysfunction remains unclear. Increased understanding of these factors is required to progress treatment development for this symptom dimension.

METHODS

This paper provides a critical overview of the literature concerning the trajectories and emerging correlates of cognitive functioning in BD. It is a narrative review in which we provide a qualitative synthesis of current evidence concerning clinical, molecular, neural and lifestyle correlates of cognitive impairment in BD across the lifespan (in premorbid, prodromal, early onset, post-onset, elderly cohorts).

RESULTS

There is emerging evidence of empirical links between cognitive impairment and an increased inflammatory state, brain structural abnormalities and reduced neuroprotection in BD. However, evidence regarding the progressive nature of cognitive impairment is mixed, since consensus between different cross-sectional data is lacking and does not align to the outcomes of the limited longitudinal studies available. Increased recognition of cognitive heterogeneity in BD may help to explain some inconsistencies in the extant literature.

CONCLUSIONS

Large, longitudinally focussed studies of cognition and its covariation alongside biological and lifestyle factors are required to better define cognitive trajectories in BD, and eventually pave the way for the application of a precision medicine approach for individual patients in clinical practice.

Functionality and Neurocognition in Patients With Bipolar Disorder After a Physical-Exercise Program (FINEXT-BD Study): Protocol of a Randomized Interventionist Program

Introduction: Recent studies have shown that symptoms of psychiatric illness, functionality, and cognitive function improve with exercise. The aim of this study will be to investigate whether the implementation of an individualized exercise program will improve the functional status of patients with bipolar disorder (BD). Methods: This longitudinal, interventional, randomized, controlled, simple-blind clinical trial will include 80 patients aged 18-65 years, all of them with BD diagnosis. Patients will be randomly assigned to a physical exercise intervention + Treatment-As-Usual (TAU) group and a non-intervention + TAU group. Patients will be assessed by an extensive battery of clinical tests, physical parameters (e.g., brain structure changes measured by optical coherence tomography, cardiorespiratory fitness) and biological parameters (inflammation, oxidative stress and neurotrophic factors) at baseline, after a 4-month intervention period, and 6-month follow-up. Discussion: This is an innovative study aimed at gaining a deeper understanding of the physiopathology of BD and determining whether the prognosis and evolution of the disease can be improved through modifiable areas of the patient's lifestyle. Clinical Trial Registration: NCT04400630. NCT clinicaltrials.gov. Date of registration in primary registry 22 May 2020. clinicaltrials.gov.

Branched-chain amino acids are associated with metabolic parameters in bipolar disorder

Objectives: An important aspect of bipolar disorder (BD) research is the identification of biomarkers pertaining to the somatic health state. The branched-chain essential amino acids (BCAAs), viz valine, leucine and isoleucine, have been proposed as biomarkers of an individual's health state, given their influence on protein synthesis and gluconeogenesis inhibition.Methods: BCAA levels of 141 euthymic/subsyndromal individuals with BD and 141 matched healthy controls (HC) were analysed by high-pressure lipid chromatography and correlated with clinical psychiatric, anthropometric and metabolic parameters.Results: BD and HC did not differ in valine and isoleucine, whereas leucine was significantly lower in BD. Furthermore, correlations were found between BCAAs and anthropometric and glucose metabolism data. All BCAAs correlated with lipid metabolism parameters in females. There were no associations between BCAAs and long-term clinical parameters of BD. A negative correlation was found between valine and Hamilton Depression-Scale, and Beck Depression Inventory II, in male individualsConclusions: Our results indicate the utility of BCAAs as biomarkers for the current state of health, also in BD. As BD individuals have a high risk for overweight/obesity, in association with comorbid medical conditions (e.g. cardiovascular diseases or insulin resistance), health state markers are urgently required. However, no illness-specific associations were found in this euthymic/subsyndromal BD group.

Physical activity as prognostic factor for bipolar disorder: An 18-month prospective study

INTRODUCTION

Exercise is an adjuvant therapy indicated for various psychiatric disorders. However, prospective studies in patients with bipolar disorder (BD) are scarce and with uncertain conclusions. This study aims to evaluate physical activity as a prognostic factor for BD, analyzing relationship with levels of anxiety, functionality, sleep, mood episodes and hospitalizations.

METHODS

Three psychiatrists interviewed 80 BD outpatients in euthymia, referred from four different institutions in Brazil. In this moment, they evaluated the intensity of physical activities using the International Physical Activity Questionnaire (IPAQ) - short form. They reevaluated patients and reviewed medical records monthly for 18 months to identify mood episodes and psychiatric hospitalizations.

RESULTS

Thirty-eight patients (47.5%) were physically inactive (or sedentary) and 42 (52.5%) active. Physically active patients had lower Body Mass Index (p = 0.006), waist circumference (p = 0.002), lower levels of anxiety (p = 0.032) and less insomnia (p = 0.001). Sedentary individuals revealed poorer global functioning (p < 0.001) and in all domains: autonomy (p < 0.001), occupational functioning (p = 0.008), cognitive functioning (p = 0.013), capacity of managing the finances (p = 0.012), interpersonal relationships (p = 0.011) and leisure time (p = 0.001). Less activity was associated with more mood episodes (p = 0.042) and psychiatric hospitalizations (p = 0.043) over 18 months.

CONCLUSION

This study suggested physical activity as a good prognostic factor for BD during euthymia. This reinforces the need to encourage this practice in clinical settings. Future prospective surveys with longer duration using objective instruments are proposed.

Gender differences in the association between physical activity and cognitive function in individuals with bipolar disorder

INTRODUCTION

Bipolar disorder (BD) is accompanied by a high number of comorbidities and associated with an overall increased mortality. Especially obesity, systemic inflammatory processes and cognitive deficits are highly prevalent and increase with the course of illness. Physical activity (PA) is associated with beneficial effects on somatic comorbidities such as obesity or cardiovascular disease in individuals without psychiatric disorder. Furthermore, PA might increase neurocognitive performance and reduce systemic inflammation.

OBJECTIVE

The aim of the study was to investigate the association between PA and neurocognitive function in euthymic individuals suffering from BD.

METHODS AND PARTICIPANTS

120 individuals with BD, euthymic at test time, completed the self-reported International Physical Activity Questionnaire (IPAQ) assessing PA of the past seven days and were accordingly assigned to a specific activity category (low, moderate or vigorous). Furthermore, clinical parameters were gathered and cognitive tests analysing verbal-dependent intelligence, attention, executive functioning as well as memory were administered.

RESULTS

Female individuals in the vigorous PA group performed significantly higher in most of the cognitive domains compared to females with moderate or low PA. In males, we only found a significant difference in one test for attention between moderate/vigorous and the low activity group.

CONCLUSION

Differences between PA groups in cognitive performance in female individuals with BD were obvious in almost all cognitive domains. As cognitive deficits are strongly associated with a worse course of disease and outcome, PA might offer a concomitant therapy targeting not only somatic comorbidities such as obesity and cardiovascular disease, but also neurocognition.

Cognitive Impairment in Bipolar Disorder: Treatment and Prevention Strategies

Over the last decade, there has been a growing appreciation of the importance of identifying and treating cognitive impairment associated with bipolar disorder, since it persists in remission periods. Evidence indicates that neurocognitive dysfunction may significantly influence patients' psychosocial outcomes. An ever-increasing body of research seeks to achieve a better understanding of potential moderators contributing to cognitive impairment in bipolar disorder in order to develop prevention strategies and effective treatments. This review provides an overview of the available data from studies examining treatments for cognitive dysfunction in bipolar disorder as well as potential novel treatments, from both pharmacological and psychological perspectives. All these data encourage the development of further studies to find effective strategies to prevent and treat cognitive impairment associated with bipolar disorder. These efforts may ultimately lead to an improvement of psychosocial functioning in these patients.

Physical Activity Modulates Common Neuroplasticity Substrates in Major Depressive and Bipolar Disorder

Mood disorders (MDs) are chronic, recurrent mental diseases that affect millions of individuals worldwide. Although the biogenic amine model has provided some clinical utility, a need remains to better understand the interrelated mechanisms that contribute to neuroplasticity deficits in MDs and the means by which various therapeutics mitigate them. Of those therapeutics being investigated, physical activity (PA) has shown clear and consistent promise. Accordingly, the aims of this review are to (1) explicate key modulators, processes, and interactions that impinge upon multiple susceptibility points to effectuate neuroplasticity deficits in MDs; (2) explore the putative mechanisms by which PA mitigates these features; (3) review protocols used to induce the positive effects of PA in MDs; and (4) highlight implications for clinicians and researchers.

Disciplined sleep for healthy living: Role of noradrenaline

Sleep is essential for maintaining normal physiological processes. It has been broadly divided into rapid eye movement sleep (REMS) and non-REMS (NREMS); one spends the least amount of time in REMS. Sleep (both NREMS and REMS) disturbance is associated with most altered states, disorders and pathological conditions. It is affected by factors within the body as well as the environment, which ultimately modulate lifestyle. Noradrenaline (NA) is one of the key molecules whose level increases upon sleep-loss, REMS-loss in particular and it induces several REMS-loss associated effects and symptoms. The locus coeruleus (LC)-NAergic neurons are primarily responsible for providing NA throughout the brain. As those neurons project to and receive inputs from across the brain, they are modulated by lifestyle changes, which include changes within the body as well as in the environment. We have reviewed the literature showing how various inputs from outside and within the body integrate at the LC neuronal level to modulate sleep (NREMS and REMS) and vice versa. We propose that these changes modulate NA levels in the brain, which in turn is responsible for acute as well as chronic psycho-somatic disorders and pathological conditions.

Physical activity and sedentary behavior in people with bipolar disorder: A systematic review and meta-analysis

BACKGROUND

Mortality rates are approximately two to three times higher in people with bipolar disorder (BD) than in general population. Lack of physical activity (PA) and sedentary behavior (SB) are independent risk factors for cardiovascular disease and premature mortality.

AIMS

We conducted a meta-analysis to investigate PA and SB levels and its predictors in BD.

METHODS

Major electronic databases were searched from inception till 02/2016 for articles measuring PA and SB with a self-report questionnaire (SRQ) or objective measure (e.g. accelerometer) in BD. A random effects meta-analysis and meta-regression analysis were conducted.

RESULTS

Six studies were eligible including 279 (129♂) people with BD (mean age=43.9 years; range: 32.0-51.5 years). The trim and fill analysis demonstrated people with BD spent in total 210.1min (95%CI=146.3-273.9min) per day being physically active and 613.3min (95%CI=389.9-836.6min) during waking hours being sedentary. No significant difference in total PA per day was observed between people with BD and controls (g=-0.62, 95% CI=-1.55 to 0.31, I(2)=88.5%, n BD =82, n controls =86). Objective measures of PA recorded significantly lower levels (P=0.03) compared to self-report PA. Meta-regression demonstrated that older age and a higher body mass index predicted lower PA levels.

LIMITATIONS

Only a limited number of studies were identified assessing SB in people with BD.

CONCLUSIONS

Adults with BD engage in high levels of sedentary behavior during waking hours. Given that sedentary behavior is an independent predictor of cardiovascular disease, future lifestyle interventions specifically targeting the prevention of sedentary behavior are warranted.

Exercise in bipolar patients: A systematic review

BACKGROUND

Sedentary lifestyle is frequent in psychiatric disorders, however the directions of this association and benefits of physical activity are unclear. This is a systematic review about exercise in patients with bipolar disorder.

METHODS

We performed a systematic literature search of studies published in English (1995 Jan to 2016 Jan) in PubMed, and Cochrane Library combining the medical terms 'physical activity' or 'sedentary' or 'physical exercise' with 'bipolar disorder' or 'mania' or 'bipolar depression'.

RESULTS

Thirty-one studies were selected and included 15,587 patients with bipolar disorder. Sedentary lifestyle varied from 40% to 64.9%. Physical activity was associated with less depressive symptoms, better quality of life and increased functioning. Some evidence indicates a relationship between vigorous exercises and mania. Three prospective cohorts were reported; and no prospective randomized controlled trial was identified. Three studies focused on biomarkers in bipolar patients; and one reported the relationship between exercise and sleep in this group. Two assessed physical exercise in adolescents.

LIMITATIONS

(1) Differences between studies preventing a unified analysis; (2) most studies were cross-sectional; (3) motivation for exercising is a selection bias in most studies; (4) no intervention study assessing only physical exercise; (5) lack of studies comparing exercise across mood states.

CONCLUSION

Generally, exercise was associated with improved health measures including depressive symptoms, functioning and quality of life. Evidence was insufficient to establish a cause-effect relationship between mood and physical exercise. Future research including randomized trials is needed to clarify the role of physical activity in bipolar patients.

Effects of acute aerobic exercise on neural correlates of attention and inhibition in adolescents with bipolar disorder

Executive dysfunction is common during and between mood episodes in bipolar disorder (BD), causing social and functional impairment. This study investigated the effect of acute exercise on adolescents with BD and healthy control subjects (HC) to test for positive or negative consequences on neural response during an executive task. Fifty adolescents (mean age 16.54±1.47 years, 56% female, 30 with BD) completed an attention and response inhibition task before and after 20 min of recumbent cycling at ~70% of age-predicted maximum heart rate. 3 T functional magnetic resonance imaging data were analyzed in a whole brain voxel-wise analysis and as regions of interest (ROI), examining Go and NoGo response events. In the whole brain analysis of Go trials, exercise had larger effect in BD vs HC throughout ventral prefrontal cortex, amygdala and hippocampus; the profile of these effects was of greater disengagement after exercise. Pre-exercise ROI analysis confirmed this 'deficit in deactivation' for BDs in rostral ACC and found an activation deficit on NoGo errors in accumbens. Pre-exercise accumbens NoGo error activity correlated with depression symptoms and Go activity with mania symptoms; no correlations were present after exercise. Performance was matched to controls and results survived a series of covariate analyses. This study provides evidence that acute aerobic exercise transiently changes neural response during an executive task among adolescents with BD, and that pre-exercise relationships between symptoms and neural response are absent after exercise. Acute aerobic exercise constitutes a biological probe that may provide insights regarding pathophysiology and treatment of BD.

Bipolar Depression and Cognitive Impairment: Shared Mechanisms and New Treatment Avenues

Depression and cognitive impairment are pervasive and highly disabling aspects of bipolar disorder. Although cognitive impairment is partially independent from mood episodes, depressive symptoms may increase the risk of cognitive impairment in bipolar disorder through inflammatory processes as well as health risks such as obesity and sedentary behavior. Novel treatment avenues at the intersection of bipolar depression and cognitive impairment target inflammation directly or indirectly health behaviors such as diet, physical activity, and sleep hygiene.

Treating to target in major depressive disorder: response to remission to functional recovery

Treating to target in chronic diseases [e.g. Major Depressive Disorder (MDD)] fosters precision, consistency, and appropriateness of treatment selection and sequencing. Therapeutic target definitions/endpoints in MDD should satisfy patient-, provider-, and societal expectations. Functional recovery in depression and return to both physical and mental health are the overarching therapeutic objectives. Treating to target in MDD implies multidimensional symptomatic remission, with a particular emphasis on cognitive function and aspects of positive mental health. Several atypical antipsychotic agents (i.e. brexpiprazole, aripiprazole, quetiapine) are FDA-approved as augmentation agents in MDD. Vortioxetine, duloxetine, and psychostimulants have evidence of independent, direct, and robust effects on cognitive function in MDD. Vortioxetine is the only agent that demonstrates efficacy across multiple cognitive domains in MDD associated with functional recovery. Measurement-based care, health information technology/systems, and integrated care models (e.g. medical homes) provide requisite tools and health environments for optimal health outcomes in MDD. Achieving remission in MDD does not equate to health. Return to positive mental health as well as full functioning provide the impetus to pivot away from traditional provider-defined outcomes toward an inclusive perspective involving patient- and society-defined outcomes (i.e. optimization of human capital). As in other chronic diseases, treating to target (e.g. cognitive function) further increases the probability of achieving optimal health outcomes.

Effects of a single bout of maximal aerobic exercise on BDNF in bipolar disorder: A gender-based response

Acute exercise increases brain-derived neurotrophic factor (BDNF) serum levels in majorly depressed and anxious patients. However, to the best of our knowledge, no study has evaluated the acute effects of exercise on BDNF serum levels in Bipolar Disorder (BD). The objective of the present study was to evaluate the peripheral BDNF serum response to a single maximum session of exercise in BD participants and age- and gender-matched healthy participants. BD participants (n=18) and age- and gender-matched healthy participants (n=18) were recruited to perform a single bout of maximal exercise on a cycle ergometer. Blood samples were collected prior to and immediately after the exercise protocol. There was a significant group effect and a significant group x time x gender interaction. BD participants presented significantly higher BDNF serum levels when compared to their healthy control counterparts. Exercise increases the BDNF levels of BD women, but not men.

High velocity circuit resistance training improves cognition, psychiatric symptoms and neuromuscular performance in overweight outpatients with severe mental illness

We developed a physical exercise intervention aimed at improving multiple determinants of physical performance in severe mental illness. A sample of 12 (9M, 3F) overweight or obese community-dwelling patients with schizophrenia (n=9) and bipolar disorder (n=3) completed an eight-week, high-velocity circuit resistance training, performed twice a week on the computerized Keiser pneumatic exercise machines, including extensive pre/post physical performance testing. Participants showed significant increases in strength and power in all major muscle groups. There were significant positive cognitive changes, objectively measured with the Brief Assessment of Cognition Scale: improvement in composite scores, processing speed and symbol coding. Calgary Depression Scale for Schizophrenia and Positive and Negative Syndrome Scale total scores improved significantly. There were large gains in neuromuscular performance that have functional implications. The cognitive domains that showed the greatest improvements (memory and processing speed) are most highly predictive of disability in schizophrenia. Moreover, the improvements seen in depression suggest this type of exercise intervention may be a valuable add-on therapy for bipolar depression.

Animal models of bipolar mania: The past, present and future

Bipolar disorder (BD) is the sixth leading cause of disability in the world according to the World Health Organization and affects nearly six million (∼2.5% of the population) adults in the United State alone each year. BD is primarily characterized by mood cycling of depressive (e.g., helplessness, reduced energy and activity, and anhedonia) and manic (e.g., increased energy and hyperactivity, reduced need for sleep, impulsivity, reduced anxiety and depression), episodes. The following review describes several animal models of bipolar mania with a focus on more recent findings using genetically modified mice, including several with the potential of investigating the mechanisms underlying 'mood' cycling (or behavioral switching in rodents). We discuss whether each of these models satisfy criteria of validity (i.e., face, predictive, and construct), while highlighting their strengths and limitations. Animal models are helping to address critical questions related to pathophysiology of bipolar mania, in an effort to more clearly define necessary targets of first-line medications, lithium and valproic acid, and to discover novel mechanisms with the hope of developing more effective therapeutics. Future studies will leverage new technologies and strategies for integrating animal and human data to reveal important insights into the etiology, pathophysiology, and treatment of BD.

A brief review of exercise, bipolar disorder, and mechanistic pathways

Despite evidence that exercise has been found to be effective in the treatment of depression, it is unclear whether these data can be extrapolated to bipolar disorder. Available evidence for bipolar disorder is scant, with no existing randomized controlled trials having tested the impact of exercise on depressive, manic or hypomanic symptomatology. Although exercise is often recommended in bipolar disorder, this is based on extrapolation from the unipolar literature, theory and clinical expertise and not empirical evidence. In addition, there are currently no available empirical data on program variables, with practical implications on frequency, intensity and type of exercise derived from unipolar depression studies. The aim of the current paper is to explore the relationship between exercise and bipolar disorder and potential mechanistic pathways. Given the high rate of medical co-morbidities experienced by people with bipolar disorder, it is possible that exercise is a potentially useful and important intervention with regard to general health benefits; however, further research is required to elucidate the impact of exercise on mood symptomology.

Treatment-resistant depression: definitions, review of the evidence, and algorithmic approach

BACKGROUND

Most adults with major depressive disorder (MDD) fail to achieve remission with index pharmacological treatment. Moreover, at least half will not achieve and sustain remission following multiple pharmacological approaches. Herein, we succinctly review treatment modalities proven effective in treatment-resistant depression (TRD).

METHODS

We conducted a review of computerized databases (PubMed, Google Scholar) from 1980 to April 2013. Articles selected for review were based on author consensus, adequacy of sample size, the use of a standardized experimental procedure, validated assessment measures and overall manuscript quality.

RESULTS

The evidence base supporting augmentation of conventional antidepressants with atypical antipsychotics (i.e., aripiprazole, quetiapine, and olanzapine) is the most extensive and rigorous of all pharmacological approaches in TRD. Emerging evidence supports the use of some psychostimulants (i.e., lisdexamfetamine) as well as aerobic exercise. In addition, treatments informed by pathogenetic disease models provide preliminary evidence for the efficacy of immune-inflammatory based therapies and metabolic interventions. Manual based psychotherapies remain a treatment option, with the most compelling evidence for cognitive behavioral therapy. Disparate neurostimulation strategies are also available for individuals insufficiently responsive to pharmacotherapy and/or psychosocial interventions.

LIMITATIONS

Compared to non-treatment-resistant depression, TRD has been less studied. Most clinical studies on TRD have focused on pharmacotherapy-resistant depression, with relatively fewer studies evaluating "next choice" treatments in individuals who do not initially respond to psychosocial and/or neurostimulatory treatments.

CONCLUSION

The pathoetiological heterogeneity of MDD/TRD invites the need for mechanistically dissimilar, and empirically validated, treatment approaches for TRD.

The effects of physical exercise in schizophrenia and affective disorders

Affective and non-affective psychoses are severe and frequent psychiatric disorders. Amongst others, they not only have a profound impact on affected individuals through their symptomatology, but also regarding cognition, brain structure and function. Cognitive impairment influences patients' quality of life as well as their ability to work and being employed. While exercise therapy has been implemented in the treatment of psychiatric conditions since the days of Kraepelin and Bleuler, the underlying mechanisms have never been systematically studied. Since the early 1990s, studies emerged examining the effect of physical exercise in animal models, revealing stimulation of neurogenesis, synaptogenesis and neurotransmission. Based on that body of work, clinical studies have been carried out in both healthy humans and in patient populations. These studies differ with regard to homogenous study samples, sample size, type and duration of exercise, outcome variables and measurement techniques. Based on their review, we draw conclusions regarding recommendations for future research strategies showing that modern therapeutic approaches should include physical exercise as part of a multimodal intervention programme to improve psychopathology and cognitive symptoms in schizophrenia and affective disorders.

A review of physical activity correlates in patients with bipolar disorder

BACKGROUND

Existing studies do suggest that physical activity interventions may be feasible and have a role in promoting mental and physical health in patients with bipolar disorder. The present review evaluates systematically quantitative studies of correlates of physical activity in patients with bipolar disorder.

METHODS

We searched EMBASE, PsycINFO, PubMed, and CINAHL from their inception, combining the medical subject headings 'bipolar disorder' or 'mania' or 'manic depression' with 'physical activity' or 'physical inactivity' or 'exercise'.

RESULTS

Out of 40 potentially eligible studies, 11 papers evaluating 26 correlates were included. Correlates that were associated with lower physical activity participation were lower self-efficacy, presence of medical co-morbidity, lower educational status and social isolation. Less consistent variables associated with lower physical activity participation included higher BMI, older age, financial strains, not being connected to a health care service, and minority ethnicity. A larger study sample size was related to a higher proportion of significant associations (p=0.04). Current gaps in literature which need to be examined more in detail are the role of psychiatric symptoms, environmental and policy-level factors.

LIMITATIONS

The diversity of physical activity measures and subject samples prevented us to perform a meta-analysis.

CONCLUSIONS

All significant correlates should be confirmed in prospective studies and interventions to improve the modifiable variables should be developed and evaluated. The reviewed data also demonstrate that validation studies on physical activity measurements are highly needed.

The relationship between bipolar disorder and type 2 diabetes: more than just co-morbid disorders

Type 2 diabetes mellitus (T2DM) rates are three times higher in patients with bipolar disorder (BD), compared to the general population. This is a major contributing factor to the elevated risk of cardiovascular mortality, the leading cause of death in bipolar patients. There may be shared pathophysiology linking the two disorders, including hypothalamic-pituitary-adrenal and mitochondrial dysfunction, common genetic links, and epigenetic interactions. Life-style, phenomenology of bipolar symptoms, and adverse effects of pharmacotherapy may be contributing factors. Patients with BD and T2DM have a more severe course of illness and are more refractory to treatment. Control of their diabetes is poorer when compared to diabetics without BD, and an existing disparity in medical care may be partly responsible. Glucose abnormalities in bipolar patients need to be screened for and treated. Metformin appears to have the best benefit/risk ratio, and the dipeptidyl peptidase-4 inhibitors and glucagon-like peptide-1 receptor agonists and analogues also appear promising, although these agents have not been specifically studied in populations with mood disorders. Physicians need to be aware of the increased risk for T2DM and cardiovascular disease in bipolar patients, and appropriate prevention, screening, case finding, and treatment is recommended.

Exercise and physical activity in mental disorders: clinical and experimental evidence

Several epidemiological studies have shown that exercise (EX) and physical activity (PA) can prevent or delay the onset of different mental disorders, and have therapeutic benefits when used as sole or adjunct treatment in mental disorders. This review summarizes studies that used EX interventions in patients with anxiety, affective, eating, and substance use disorders, as well as schizophrenia and dementia/mild cognitive impairment. Despite several decades of clinical evidence with EX interventions, controlled studies are sparse in most disorder groups. Preliminary evidence suggests that PA/EX can induce improvements in physical, subjective and disorder-specific clinical outcomes. Potential mechanisms of action are discussed, as well as implications for psychiatric research and practice.

Is neurogenesis relevant in depression and in the mechanism of antidepressant drug action? A critical review

OBJECTIVES

Major depression is a complex disorder that involves genetic, epigenetic and environmental factors in its aetiology. Recent research has suggested that hippocampal neurogenesis may play a role in antidepressant action. However, careful examination of the literature suggests that the complex biological and psychological changes associated with depression cannot be attributed to disturbance in hippocampal neurogenesis alone. While antidepressants may induce hippocampal neurogenesis in non-human primates, there is a paucity of evidence that such effects are sufficient for full therapeutic action in humans.

METHODS

This review examines the literature on neurogenesis and discusses the stress-induced cortisol neurotoxicity and antidepressant-induced neurogenesis rescue model of depression. The disparity between a simple antidepressant-induced neurogenesis rescue model in the hippocampus and the complexity of clinical depression is analyzed through critical evaluation of recent research data.

RESULTS AND CONCLUSIONS

Major depression is a complex brain disorder with multiple symptoms and disturbances reflecting dysfunction in more than one single brain area. Initial research suggesting a model of hippocampal degeneration as basis of depression, and reversal by antidepressants through neurogenesis seems to be over-simplified given the emergence of new data. Synaptogenesis and re-organization or re-integration of new neurons rather than simple addition of new neurons may underlie the role of antidepressant drugs in the reversal of some but not all symptoms in depression. The importance of the neurogenesis hypothesis of depression and antidepressant action lies in stimulating further research into the possible roles played by the new neurons and synapses generated.

'It's a double edged sword': a qualitative analysis of the experiences of exercise amongst people with Bipolar Disorder

BACKGROUND

Little is known about the therapeutic or iatrogenic effects of exercise in individuals with Bipolar Disorder, despite its potential to benefit physical and mental health. Consequently the aim of the current study was to gather data on experiences of the relationship between exercise and Bipolar Disorder from people with personal experience of the condition. In particular we sought to determine the aspects of this relationship that are pertinent to Bipolar Disorder.

METHODS

Twenty five individuals with a diagnosis of Bipolar Disorder participated in a semi-structured interview concerning their views on the relationship between exercise and Bipolar Disorder. The data were subjected to qualitative analysis using an Interpretative Phenomenological Analysis approach.

RESULTS

Both a descriptive content analysis and a population-specific thematic analysis were conducted. The latter revealed three themes, all present in the majority of participants, which reflected key aspects of the relationship between Bipolar Disorder and exercise: regulating exercise for mood regulation, exercise as a double-edged sword, and bringing structure to chaos.

LIMITATIONS

Information on past and current treatment regimes was not collected, and additional lifestyle factors, such as diet and alcohol use, were not investigated. Interviews were conducted by telephone.

CONCLUSIONS

The data reveal a number of aspects of the relationship between exercise and Bipolar Disorder that require further investigation and that should be taken into account by clinicians or researchers designing exercise-based interventions for individuals with Bipolar Disorder.

Stochastic resonance activity influences serum tryptophan metabolism in healthy human subjects

Background

Stochastic resonance therapy (SRT) is used for rehabilitation of patients with various neuropsychiatric diseases. An alteration in tryptophan metabolism along the kynurenine pathway has been identified in the central and peripheral nervous systems in patients with neuroinflammatory and neurodegenerative diseases and during the aging process. This study investigated the effect of SRT as an exercise activity on serum tryptophan metabolites in healthy subjects.

Methods

Serum L-tryptophan, L-kynurenine, kynurenic acid, and anthranilic acid levels were measured one minute before SRT and at one, 5, 15, 30, and 60 minutes after SRT. We found that SRT affected tryptophan metabolism. Serum levels of L-tryptophan, L-kynurenine, and kynurenic acid were significantly reduced for up to 60 minutes after SRT. Anthranilic acid levels were characterized by a moderate, non significant transient decrease for up to 15 minutes, followed by normalization at 60 minutes. Tryptophan metabolite ratios were moderately altered, suggesting activation of metabolism after SRT. Lowering of tryptophan would generally involve activation of tryptophan catabolism and neurotransmitter, protein, and bone biosynthesis. Lowering of kynurenic acid by SRT might be relevant for improving symptoms in patients with neuropsychiatric disorders, such as Parkinson’s disease, Alzheimer’s disease, schizophrenia, and depression, as well as certain pain conditions.

Exercise and physical activity in mental disorders

Exercise (EX) and physical activity (PA) have been shown to prevent or delay the onset of several mental disorders and to have therapeutic effects in different groups of psychiatric disorders. This review focuses on studies investigating EX as therapeutic intervention in anxiety disorders, affective disorders, eating disorders, schizophrenia, and substance use disorders. Despite EX being discussed as a potential therapy for several decades, adequately powered randomized, controlled trials are sparse in most disorder groups. Nevertheless, evidence points toward disorder-specific benefits that can be induced by EX/PA. Mechanisms of the therapeutic effects of EX/PA are summarized, including metabolic and physiological as well as psychological aspects. Finally, implications for research and therapeutic practice are illustrated.

Neurocognitive performance in children and adolescents with bipolar disorder: a review

A number of studies have reported the evidence of cognitive deficits in adult bipolar patients. Recently, there has been a shift in research on neurocognitive performance in bipolar disorder (BD) towards examining younger age groups. A review of the literature on neurocognitive impairments in BD in childhood and adolescence was conducted. We searched systematically for studies in samples of age groups younger than 18 years of age in average that included either a healthy control group or normative data for the cognitive tests used. Twenty-one original articles were found and reviewed. Children and adolescents with BD show deficits in a variety of cognitive areas. The most consistent results were found for impairments in verbal memory. A majority of studies also indicated impairments in working memory. Similar pattern of neurocognitive impairment was found in children and adolescents as compared to adults suffering from BD. The neurocognitive deficits need to be recognized and incorporated into individual treatment programs.