The impact of endurance training and table soccer on brain metabolites in schizophrenia

The effect of physical exercise on cognitive function in schizophrenia patients: A GRADE assessed systematic review and meta-analysis of controlled clinical trials

BACKGROUND

Physical exercise has demonstrated the potential to improve cognitive impairment in schizophrenia, although the results are limited. The objective of this meta-analysis is to synthesize the existing evidence on the impact of physical exercise on cognitive functions in schizophrenia.

METHODS

A systematic search of PubMed, Scopus, Web of Science, and Embase was conducted. The study included controlled clinical trials on patients with schizophrenia that received physical exercise as the intervention for improving cognition. A meta-analysis was conducted using a random-effects model, and the outcomes were reported using the standardized mean difference (SMD) and a 95 % confidence interval (95 % CI).

RESULTS

A total of 22 articles, including 1066 patients (565 in the intervention group and 501 in the control group), were included in the final analysis. Physical exercises significantly improved global cognition (SMD: 0.73, 95 % CI (0.46-1.00), P < 0.001), and aerobic exercise was found to have a more significant effect than resistance and mindfulness exercise (SMD: 0.76, 95 % CI (0.45-1.07), P < 0.001). The speed of processing [SMD: 0.88, 95 % CI (0.37-1.38), P = 0.001], attention [SMD: 0.61, 95 % CI (0.20-1.02), P = 0.004], and visual learning memory [SMD: 1.42, 95 % CI (0.14-2.71), P = 0.03] demonstrated significant improvement after physical exercise, while no significant effects were observed on working memory, verbal learning memory, reasoning and problem-solving, and social cognition.

CONCLUSIONS

Exercise can improve overall cognitive function in people with Schizophrenia. However, it is unclear whether this improvement is significant in specific cognitive domains.

Glutamatergic neurotransmission in schizophrenia: A systematic review and quantitative synthesis of proton magnetic resonance spectroscopy studies across schizophrenia spectrum disorders

OBJECTIVE

Studies using proton magnetic resonance spectroscopy reveal substantial inconsistencies in the levels of brain glutamate, glutamine and glutamate + glutamine across schizophrenia spectrum disorders. This systematic review employs qualitative and quantitative methods to analyse the patterns and relationships between glutamatergic metabolites, schizophrenia spectrum disorders and brain regions.

METHODS

A literature search was conducted using various databases with keywords including glutamate, glutamine, schizophrenia, psychosis and proton magnetic resonance spectroscopy. Inclusion criteria were limited to case-control studies that reported glutamatergic metabolite levels in adult patients with a schizophrenia spectrum disorder diagnosis - i.e. first-episode psychosis, schizophrenia, treatment-resistant schizophrenia and/or ultra-treatment-resistant schizophrenia - using proton magnetic resonance spectroscopy at 3 T or above. Pooled study data were synthesized and analysed.

RESULTS

A total of 92 studies met the inclusion criteria, including 2721 healthy controls and 2822 schizophrenia spectrum disorder participants. Glu levels were higher in the basal ganglia, frontal cortex and medial prefrontal of first-episode psychosis participants, contrasting overall lower levels in schizophrenia participants. For Gln, strong differences in metabolite levels were evident in the basal ganglia, dorsolateral prefrontal cortex and frontal cortex, with first-episode psychosis showing significantly higher levels in the basal ganglia. In glutamate + glutamine, higher metabolite levels were found across schizophrenia spectrum disorder groups, particularly in the basal ganglia and dorsolateral prefrontal cortex of treatment-resistant schizophrenia participants. Significant relationships were found between metabolite levels and medication status, clinical measures and methodological variables.

CONCLUSION

The review highlights abnormal glutamatergic metabolite levels throughout schizophrenia spectrum disorders and in specific brain regions. The review underscores the importance of standardized future research assessing glutamatergic metabolites using proton magnetic resonance spectroscopy due to considerable literature heterogeneity.

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.

Effect of high-intensity interval training on hippocampal metabolism in older adolescents

Although well-evidenced in older adults, the effects of exercise on the hippocampus in youth are relatively unknown. This study examined the impact of a 6-month school-based physical activity intervention on hippocampal metabolism in adolescents using magnetic resonance spectroscopy. A subset of lower fit older adolescents [N = 56, 61% female, 16.1 ± 0.4 years] was included from four secondary schools (10 classes) in New South Wales, Australia, who were participating in a larger cluster randomized controlled trial. Participants were randomized to the Burn 2 Learn (B2L) intervention (five classes, 30 participants) or a control group (five classes, 26 participants). Changes in hippocampal metabolism were assessed using linear mixed models adjusted for clustering at the class level. We observed group-by-time effects for the B2L intervention on N-acetylaspartate (NAA) (+2.66 mmol/L, 95% CI 0.20 to 5.11, d = 0.66) and glutamate+glutamine (Glx) (+3.38 mmol/L, 95% CI 0.34 to 6.42, d = 0.67) in the left hippocampus. Increases in left hippocampal NAA and Glx concentrations were associated with improvements in cardiorespiratory fitness (NAA: r_s  = 0.52, p = .016; Glx: r_s  = 0.57, p = .007), lower body muscular fitness (NAA: r_s  = 0.49, p = .018; Glx: r_s  = 0.59, p = .003), and working memory (NAA: r_s  = 0.42, p = .032; Glx: r_s  = 0.43, p = .028) in the intervention group. Our findings suggest physical activity may improve hippocampal metabolism in lower fit older adolescents with implications for working memory. Further studies involving larger samples are needed to replicate our findings.

Impact of aerobic exercise on cognitive function in patients with schizophrenia during daily care: A meta-analysis

To assess the effect of aerobic exercise (AZ) on global cognition and different cognition domains in patients with schizophrenia (SZ) in daily care. Selection of the literature was done through the Pubmed, Web of Science, Embase and Cochrane Library databases. Standardized mean difference (SMD) and 95% confidence intervals (CIs) were used to assess the effect of AZ on cognition of SZ patients. All assessment indicators were subjected to sensitivity analysis to test the stability of the result. Subgroup analysis was conducted on study type, follow-up time, supervisor and control method. Totally, 23 articles enrolling 1014 participants were included. The global cognition of SZ patients was improved after 6 months of follow-up. AE guided by an occupational therapist improved the global cognition of SZ patients. AE was associated with improved verbal learning and memory, reasoning and problem solving (SMD: 0.375, 95%CI: 0.009 to 0.741, P = 0.045). However, effects on speed of processing, attention/vigilance, work memory, visual learning and memory, social cognition were not significant. The effect of AE training on global cognition may be maintained over the long-term, and be domain specific. Patients with SZ can do AE guided by professional occupational therapist in their daily lives settings.

Aerobic exercise in severe mental illness: requirements from the perspective of sports medicine

Major depression, bipolar disorder, and schizophrenia are severe mental illnesses. Despite receiving psychopharmacological and psychosocial treatments, about half of patients develop a chronic course with residual cognitive and negative symptoms and have a high risk for cardiovascular disease and reduced life expectancy. Therefore, add-on innovative treatment approaches are needed to improve outcome. Aerobic exercise interventions have been shown to improve global functioning, cognition, and negative and depressive symptoms in these patients. The basic mechanism of these exercise-related changes has been reported to be improved brain plasticity, e.g., increased volume of disease-related brain regions such as the hippocampus. The optimal type, duration, and frequency of exercise have not yet been determined and need to be addressed in supervised physical exercise studies. Because of the low physical activity levels, lack of drive related to negative and depressive symptoms, and high prevalence of cardiovascular comorbidities in patients with severe mental illness, besides aiming to improve symptoms of mental illness, exercise interventions should also aim to increase cardiorespiratory fitness, which they should comprehensively assess by direct measurements of maximal oxygen uptake. Based on the recommendations for developing cardiorespiratory fitness by the American College of Sports Medicine, 150 min moderate-intensity training per week or vigorous-intensity exercise training for 75 min per week are appropriate. Most studies have had relatively short intervention periods, so future studies should focus on long-term adherence to exercise by implementing motivational strategies supported by telemedicine and by identifying and targeting typical barriers to exercise in this patient population.

Proton Magnetic Resonance Spectroscopy of N-acetyl Aspartate in Chronic Schizophrenia, First Episode of Psychosis and High-Risk of Psychosis: A Systematic Review and Meta-Analysis

N-acetyl-aspartate (NAA) is a readily measured marker of neuronal metabolism. Previous analyses in schizophrenia have shown NAA levels are low in frontal, temporal and thalamic regions, but may be underpowered to detect effects in other regions, in high-risk states and in first episode psychosis. We searched for magnetic resonance spectroscopy studies comparing NAA in chronic schizophrenia, first episode psychosis and high risk of psychosis to controls. 182 studies were included and meta-analysed using a random-effects model for each region and illness stage. NAA levels were significantly lower than controls in the frontal lobe [Hedge's g = -0.36, p < 0.001], hippocampus [-0.52, p < 0.001], temporal lobe [-0.35, p = 0.031], thalamus [-0.32, p = 0.012] and parietal lobe [-0.25, p = 0.028] in chronic schizophrenia, and lower than controls in the frontal lobe [-0.26, p = 0.002], anterior cingulate cortex [-0.24, p = 0.016] and thalamus [-0.28, p = 0.028] in first episode psychosis. NAA was lower in high-risk of psychosis in the hippocampus [-0.20, p = 0.049]. In schizophrenia, NAA alterations appear to begin in hippocampus, frontal cortex and thalamus, and extend later to many other regions.