Effect of high-endurance exercise intervention on sleep-dependent procedural memory consolidation in individuals with schizophrenia: a randomized controlled trial

Systematic Review and Meta-analysis of Exercise Interventions for Psychotic Disorders: The Impact of Exercise Intensity, Mindfulness Components, and Other Moderators on Symptoms, Functioning, and Cardiometabolic Health

BACKGROUND AND HYPOTHESIS

Exercise therapy has been shown to be an effective complementary treatment for patients with psychotic disorders. However, the specific impacts of different training modalities remain poorly understood. This article aims to quantitatively review the moderating influence of different exercise modalities, hypothesizing that higher exercise intensity as well as utilization of mindfulness-based exercise (MBE) components, will improve intervention outcomes.

STUDY DESIGN

PubMed, Web of Science, and PsycINFO were searched from 2010 to March 2022 for randomized controlled trials investigating exercise interventions in patients with psychotic disorders (preregistration: https://doi.org/10.17605/OSF.IO/J8QNS). Outcomes considered were positive/negative symptoms, Positive and Negative Syndrome Scale (PANSS) General Psychopathology/Total scores, depressive symptoms, psychosocial functioning, quality of life, cardiorespiratory fitness, and body mass index. Separate meta-analyses, including moderator analyses, were performed to evaluate the moderating influence of different training modalities.

STUDY RESULTS

Of 6653 studies, 40 (n = 2111 patients) were included in the meta-analysis. The effects of moderate-intensity exercise exceed low-intensity approaches for PANSS Total scores (P = .02) and depressive symptoms (P = .04). The presence of MBE components was associated with improvements in positive symptoms (P = .04) and PANSS General Psychopathology subscores (P = .04) but also with higher error and between-study heterogeneity. Our analysis also shows improved intervention effects on depression in younger patients (P = .012) and improved psychosocial functioning scores following more frequent sessions (P < .01).

CONCLUSIONS

A minimum of moderate intensity should be considered. More frequent training sessions per week also seem to be beneficial. While adding mindfulness elements is promising, it increases heterogeneity and requires caution in terms of generalization.

Comparative efficacy of different types of exercise modalities on psychiatric symptomatology in patients with schizophrenia: a systematic review with network meta-analysis

This network meta-analysis investigated the effects of 8 types of physical exercises on treating positive symptoms, negative symptoms, general psychopathology, and the Positive And Negative Syndrome Scale (PANSS) total score in patients with schizophrenia. The methods adhered to PRISMA guidelines and used the Cochrane risk of bias tool for quality assessment, and Stata software for data analysis. Data were sourced from PubMed, Embase, Web of Science, and the Cochrane database up to August 15, 2023, following PICOS principles. A total of 25 studies including 1441 participants were analyzed. Results showed that resistance exercise seems to be effective for improving positive symptoms, while Yoga was more effective for negative symptoms. Low-intensity aerobic exercise was optimal for general psychopathology, and Yoga was effective in improving the PANSS total score. The study concluded that yoga and aerobic exercise demonstrated superior performance, but the impact of exercise on patients with schizophrenia is also influenced by individual factors and intervention dosages. Therefore, a pre-assessment of patients considering factors such as interests, hobbies, and physical capabilities is crucial for selecting appropriate exercise modalities.

The effect of exercise on cognition and clinical symptoms of patients with schizophrenia: A systematic review of randomized controlled trial

Physical activity has been viewed as a potential non-pharmacological therapeutic strategy to improve the clinical symptoms and neurocognitive deficits in patients with schizophrenia. However, there are various types of physical activities, and different exercise prescriptions might produce inconsistent benefits. Thus, this study aimed to conduct a systematic review of exercise interventions for patients with schizophrenia, clarifying the benefits of these interventions on cognitive function and clinical symptoms. This review encompasses six electronic databases, with inclusion criteria including randomized controlled trial designs, participants with schizophrenia, and a comprehensive exercise intervention program. Twenty-seven studies met the inclusion criteria, incorporating data from 1549 patients with schizophrenia. The results highlight that when comparing the exercise intervention group to the non-intervention control group, patients with schizophrenia showed significant improvement in negative symptoms. Structured exercise interventions can help improve the negative symptoms of schizophrenia, filling the gaps where medication falls short. Regarding functional outcomes, exercise interventions aid in enhancing the overall functionality (psychological, social, occupational) of individuals with schizophrenia. The improvement is largely tied to the boost in physical fitness that exercise provides. Based on current findings, exercise interventions assist in enhancing cognitive function in patients with schizophrenia. Notably, significant improvements are observed in higher-order cognitive functions, including processing speed, attention, and working memory. It is recommended to engage in moderate-intensity exercises at least three times a week, with each session lasting a minimum of 30min. Well-structured exercise interventions contribute to enhancing the negative symptoms and cognitive functions in patients with schizophrenia.

Efficacy and feasibility of aerobic exercise interventions as an adjunctive treatment for patients with schizophrenia: a meta-Analysis

Schizophrenia is a chronic mental disorder primarily treated with antipsychotics, which have limited efficacy for negative symptoms. This study aims to evaluate the effectiveness and feasibility of exercise interventions as adjuncts to pharmacotherapy through a meta-analysis, providing valuable insights for rational intervention design. Four databases were searched, and randomized controlled trials with no language restrictions published up to March 27, 2023, were included. The primary outcome indicator was the Positive and Negative Symptom Scale (PANSS) total score along with its three sub-scales. Secondary outcomes included the Scale for Assessment of Negative Symptoms (SANS) and Body Mass Index (BMI), which were used to assess the efficacy of aerobic exercise interventions in patients with schizophrenia. Subgroup analyses were conducted to explore the impact of intervention duration and total weekly exercise time, while treatment feasibility was assessed through adherence rates. A total of 17 publications involving 973 patients with schizophrenia were deemed eligible and included in the analysis. Compared to other forms of adjunctive interventions, the network meta-analysis of 12 PANSS-based studies revealed that adjunctive aerobic exercise interventions were the most effective in reducing overall PANSS scores in patients with schizophrenia, with statistically significant pooled results (MD = -4.84, 95% CI: -5.72, -3.96). Both the PANSS negative symptom subscale (MD = -2.11, 95% CI: -3.26, -0.95) and SANS (MD = -9.11, 95% CI: -11.94, -6.27) indicated that adjunctive aerobic exercise interventions effectively alleviate negative symptoms. Subgroup meta-analysis indicated that 2-3 month interventions involving 100-220 min of exercise per week were the most effective. Additionally, adherence to the adjunctive aerobic exercise regimen was found to be comparable to that of conventional treatment alone. Aerobic exercise interventions, as adjunctive therapy, are an effective measure for reducing PANSS scores in patients with schizophrenia, contributing to the alleviation of both the positive and negative symptoms, and patients demonstrated strong adherence to aerobic exercise.

The Impact of Regular Physical Exercise on Psychopathology, Cognition, and Quality of Life in Patients Diagnosed with Schizophrenia: A Scoping Review

The presence of less healthy lifestyle habits among individuals diagnosed with schizophrenia which can contribute to the escalation of physical disorders and exacerbation of psychological symptoms is well documented. The present scoping review aims to synthesize and evaluate the available evidence regarding the impact of regular physical exercise on psychopathology, cognition, and quality of life (QoL) in patients diagnosed with schizophrenia. A literature search was performed across Web of Science, SCOPUS, PubMed, and SPORTDiscus for randomized control trials published up to April 2022. Two independent reviewers applied the selection criteria and a third reviewer resolved discrepancies. A total of twelve studies were included, of which nine used endurance training and three used concurrent training (one of these additionally used resistance training). The results reveal benefits of various modalities of supervised regular exercise in the psychopathology of schizophrenia. Furthermore, regular endurance training seems to improve cognitive function in patients with schizophrenia and promote their QoL; however, results are inconclusive with respect to this last variable. The assessment of methodological quality in the reviewed articles indicates a high overall risk of bias, particularly in relation to deviations from intended interventions and the selection of reported results. Furthermore, an assessment of exercise reporting revealed that only 5 out of 19 items were fulfilled in more than 50% of the articles. Future research is needed to evaluate the effects of different training modalities and the optimal dose-response relationship in patients diagnosed with schizophrenia.

Spurious Autobiographical Memory of Psychosis: A Mechanistic Hypothesis for the Resolution, Persistence, and Recurrence of Positive Symptoms in Psychotic Disorders

Psychotic disorders are complex disorders with multiple etiologies. While increased dopamine synthesis capacity has been proposed to underlie psychotic episodes, dopamine-independent processes are also involved (less responsive to dopamine receptor-blocking medications). The underlying mechanism(s) of the reduction in antipsychotic responsiveness over time, especially after repeated relapses, remain unclear. Despite the consistent evidence of dopamine overactivity and hippocampal volume loss in schizophrenia, few accounts have been provided based on the interactive effect of dopamine on hippocampal synapse plasticity mediating autobiographical memory processes. The present hypothesis builds upon previous works showing the potential effects of dopamine overactivity on hippocampal-mediated neuroplasticity underlying autobiographical memory, alongside known patterns of autobiographical memory dysfunction in psychosis. We propose that spurious autobiographical memory of psychosis (SAMP) produced during active psychosis may be a key mechanism mediating relapses and treatment non-responsiveness. In a hyperdopaminergic state, SAMP is expected to be generated at an increased rate during active psychosis. Similar to other memories, it will undergo assimilation, accommodation, and extinction processes. However, if SAMP fails to integrate with existing memory, a discontinuity in autobiographical memory may result. Inadequate exposure to normalizing experiences and hyposalience due to overmedication or negative symptoms may also impede the resolution of SAMP. Residual SAMP is hypothesized to increase the propensity for relapse and treatment non-responsiveness. Based on recent findings on the role of dopamine in facilitating hippocampal synapse plasticity and autobiographical memory formation, the SAMP hypothesis is consistent with clinical observations of DUP effects, including the repetition of contents in psychotic relapses as well as the emergence of treatment non-responsiveness after repeated relapses. Clinical implications of the hypothesis highlight the importance of minimizing active psychosis, integrating psychosis memory, avoiding over-medication, and fostering normalizing experiences.

Sleep-dependent memory consolidation in schizophrenia: A systematic review and meta-analysis

Sleep disturbances and cognitive impairment are both persistent and common features of schizophrenia. Accumulating evidence indicates that sleep-dependent memory consolidation might be impaired in patients with schizophrenia compared to healthy controls. The current systematic review was performed in accordance with PRISMA guidelines. A random-effects model was used to calculate effect sizes (Hedge's g). In the quantitative review, three separate meta-analyses were conducted for procedural memory in healthy controls, schizophrenia, and comparison between healthy controls and schizophrenia. Additionally, separate meta-analyses were conducted for the studies using finger tapping motor sequence task, as it is the most commonly used task. The current systematic review included 14 studies including 304 patients with schizophrenia and 209 healthy controls. The random-effects model analyses for sleep-dependent procedural memory consolidation resulted in a small effect size in schizophrenia (g = 0.26), a large effect size in healthy controls (g = 0.98), a moderate effect size in healthy controls vs schizophrenia (g = 0.64). For the studies using finger tapping motor sequence task, meta-analyses resulted in a small effect size in schizophrenia (g = 0.19), a large effect size in healthy controls (g = 1.07), a moderate effect size in healthy controls vs schizophrenia (g = 0.70). In the qualitative review, there was also impaired sleep-dependent declarative memory consolidation in schizophrenia compared to healthy controls. Current findings support that sleep improves memory consolidation in healthy adults, but there is a deficit in sleep-dependent memory consolidation in people with schizophrenia. Future studies investigating sleep-dependent consolidation of different memory subtypes with polysomnography in different stages of psychotic disorders are needed.

Comparative Effectiveness of Multiple Exercise Interventions in the Treatment of Mental Health Disorders: A Systematic Review and Network Meta-Analysis

BACKGROUND

The efficacy of exercise interventions in the treatment of mental health disorders is well known, but research is lacking on the most efficient exercise type for specific mental health disorders.

OBJECTIVE

The present study aimed to compare and rank the effectiveness of various exercise types in the treatment of mental health disorders.

METHODS

The PubMed, Web of Science, PsycINFO, SPORTDiscus, CINAHL databases, and the Cochrane Central Register of Controlled Trials as well as Google Scholar were searched up to December 2021. We performed pairwise and network meta-analyses as well as meta-regression analyses for mental health disorders in general and each type of mental health disorder, with alterations in symptom severity as the primary outcome.

RESULTS

A total of 6456 participants from 117 randomized controlled trials were surveyed. The multimodal exercise (71%) had the highest probability of being the most efficient exercise for relieving depressive symptoms. While resistance exercise (60%) was more likely to be the most effective treatment for anxiety disorder, patients with post-traumatic stress disorder (PTSD) benefited more from mind-body exercise (52%). Furthermore, resistance exercise (31%) and multimodal exercise (37%) had more beneficial effects in the treatment of the positive and negative symptoms of schizophrenia, respectively. The length of intervention and exercise frequency independently moderated the effects of mind-body exercise on depressive (coefficient = 0.14, p = .03) and negative schizophrenia (coefficient = 0.96, p = .04) symptoms.

CONCLUSION

Multimodal exercise ranked best for treating depressive and negative schizophrenic symptoms, while resistance exercise seemed to be more beneficial for those with anxiety-related and positive schizophrenic symptoms. Mind-body exercise was recommended as the most promising exercise type in the treatment of PTSD. However, the findings should be treated with caution due to potential risk of bias in at least one dimension of assessment and low-to-moderate certainty of evidence. Trial Registration This systematic review was registered in the PROSPERO international prospective register of systematic reviews (CRD42022310237).

Molecular Mechanisms of Exercise and Healthspan

Healthspan is the period of our life without major debilitating diseases. In the modern world where unhealthy lifestyle choices and chronic diseases taper the healthspan, which lead to an enormous economic burden, finding ways to promote healthspan becomes a pressing goal of the scientific community. Exercise, one of humanity's most ancient and effective lifestyle interventions, appears to be at the center of the solution since it can both treat and prevent the occurrence of many chronic diseases. Here, we will review the current evidence and opinions about regular exercise promoting healthspan through enhancing the functionality of our organ systems and preventing diseases.