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Molecular Psychiatry Dec 2023A body of pre-clinical evidence shows how the gut microbiota influence brain functioning, including brain connectivity. Linking measures of brain connectivity to the gut...
A body of pre-clinical evidence shows how the gut microbiota influence brain functioning, including brain connectivity. Linking measures of brain connectivity to the gut microbiota can provide important mechanistic insights into the bi-directional gut-brain communication. In this systematic review, we therefore synthesized the available literature assessing this association, evaluating the degree of consistency in microbiota-connectivity associations. Following the PRISMA guidelines, a PubMed search was conducted, including studies published up to September 1, 2022. We identified 16 studies that met the inclusion criteria. Several bacterial genera, including Prevotella, Bacteroides, Ruminococcus, Blautia, and Collinsella were most frequently reported in association with brain connectivity. Additionally, connectivity of the salience (specifically the insula and anterior cingulate cortex), default mode, and frontoparietal networks were most frequently associated with the gut microbiota, both in terms of microbial diversity and composition. There was no discernible pattern in the association between microbiota and brain connectivity. Altogether, based on our synthesis, there is evidence for an association between the gut microbiota and brain connectivity. However, many findings were poorly replicated across studies, and the specificity of the association is yet unclear. The current studies show substantial inter-study heterogeneity in methodology and reporting, limiting the robustness and reproducibility of the findings and emphasizing the need to harmonize methodological approaches. To enhance comparability and replicability, future research should focus on further standardizing processing pipelines and employing data-driven multivariate analysis strategies.
Topics: Humans; Gastrointestinal Microbiome; Brain; Brain-Gut Axis; Connectome; Nerve Net
PubMed: 37479779
DOI: 10.1038/s41380-023-02146-4 -
JAMA Psychiatry May 2023Individuals with bipolar disorder (BD) experience cognitive and emotional dysfunctions. Various brain circuits are implicated in BD but have not been investigated in a... (Meta-Analysis)
Meta-Analysis
IMPORTANCE
Individuals with bipolar disorder (BD) experience cognitive and emotional dysfunctions. Various brain circuits are implicated in BD but have not been investigated in a meta-analysis of functional magnetic resonance imaging (fMRI) studies.
OBJECTIVE
To investigate the brain functioning of individuals with BD compared with healthy control individuals in the domains of emotion processing, reward processing, and working memory.
DATA SOURCES
All fMRI experiments on BD published before March 2020, as identified in a literature search of PubMed, Embase, Web of Science, Cochrane Library, PsycInfo, Emcare, Academic Search Premier, and ScienceDirect. The literature search was conducted on February 21, 2017, and March 2, 2020, and data were analyzed from January 2021 to January 2022.
STUDY SELECTION
fMRI experiments comparing adult individuals with BD and healthy control individuals were selected if they reported whole-brain results, including a task assessing at least 1 of the domains. In total, 2320 studies were screened, and 253 full-text articles were evaluated.
DATA EXTRACTION AND SYNTHESIS
A total of 49 studies were included after selection procedure. Coordinates reporting significant activation differences between individuals with BD and healthy control individuals were extracted. Differences in brain region activity were tested using the activation likelihood estimation method.
MAIN OUTCOMES AND MEASURES
A whole-brain meta-analysis evaluated whether reported differences in brain activation in response to stimuli in 3 cognitive domains between individuals with BD and healthy control individuals were different.
RESULTS
The study population included 999 individuals with BD (551 [55.2%] female) and 1027 healthy control individuals (532 [51.8%] female). Compared with healthy control individuals, individuals with BD showed amygdala and hippocampal hyperactivity and hypoactivation in the inferior frontal gyrus during emotion processing (20 studies; 324 individuals with BD and 369 healthy control individuals), hyperactivation in the orbitofrontal cortex during reward processing (9 studies; 195 individuals with BD and 213 healthy control individuals), and hyperactivation in the ventromedial prefrontal cortex and subgenual anterior cingulate cortex during working memory (20 studies; 530 individuals with BD and 417 healthy control individuals). Limbic hyperactivation was only found during euthymia in the emotion and reward processing domains; abnormalities in frontal cortex activity were also found in individuals with BD with mania and depression.
CONCLUSIONS AND RELEVANCE
This systematic review and meta-analysis revealed evidence for activity disturbances in key brain areas involved in cognitive and emotion processing in individuals with BD. Most of the regions are part of the fronto-limbic network. The results suggest that aberrations in the fronto-limbic network, present in both euthymic and symptomatic individuals, may be underlying cognitive and emotional dysfunctions in BD.
Topics: Adult; Humans; Female; Male; Bipolar Disorder; Brain; Emotions; Prefrontal Cortex; Magnetic Resonance Imaging; Cognition
PubMed: 36988918
DOI: 10.1001/jamapsychiatry.2023.0131 -
General Hospital Psychiatry 2024Several types of neuromodulation have been investigated for the treatment of fibromyalgia, but they show varied efficacy on pain, functioning, comorbid depression and... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
Several types of neuromodulation have been investigated for the treatment of fibromyalgia, but they show varied efficacy on pain, functioning, comorbid depression and comorbid anxiety. Whether some types of neuromodulation or some factors are associated with a better response also awaits clarification.
METHODS
We conducted a systematic review and network meta-analysis of randomized controlled trials to evaluate the efficacy of neuromodulation in patients with fibromyalgia. We searched PubMed, EMBASE, the Cochrane Central Register of Controlled Trials and PsycINFO before March 2022. We employed a frequentist random-effects network meta-analysis.
RESULTS
Forty trials involving 1541 participants were included. Compared with sham control interventions, several types of transcranial direct current stimulation (tDCS), transcranial random noise stimulation (tRNS), and high-frequency repetitive transcranial magnetic stimulation (rTMS) were associated with significant reduction of pain, depression, anxiety, and improvement in functioning. Many significantly effective treatment options involve stimulation of the primary motor cortex or dorsolateral prefrontal cortex.
CONCLUSION
We concluded that several types of rTMS, tDCS and tRNS may have the potential to be applied for clinical purposes.
Topics: Humans; Fibromyalgia; Transcranial Direct Current Stimulation; Network Meta-Analysis; Transcranial Magnetic Stimulation; Pain; Treatment Outcome
PubMed: 38382420
DOI: 10.1016/j.genhosppsych.2024.01.007 -
BMJ Supportive & Palliative Care Mar 2021Randomised controlled trials (RCTs) demonstrated benefits of pharmacological interventions for cachexia in improving weight and appetite. However, comparative efficacy... (Meta-Analysis)
Meta-Analysis
AIMS
Randomised controlled trials (RCTs) demonstrated benefits of pharmacological interventions for cachexia in improving weight and appetite. However, comparative efficacy and safety are not available. We conducted a systematic review and network meta-analysis (NMA) to evaluate the relative efficacy and safety of pharmacological interventions for cachexia.
METHODS
PubMed, EmBase, Cochrane, and ClinicalTrials.gov were searched for RCTs until October 2019. Key outcomes were total body weight (TBW) improvement, appetite (APP) score and serious adverse events. Two reviewers independently extracted data and assessed risk of bias. NMA was performed to estimate weight gain and APP score increase at 8 weeks, presented as mean difference (MD) or standardised MD with 95% CI.
RESULTS
80 RCTs (10 579 patients) with 12 treatments were included. Majority is patients with cancer (7220). Compared with placebo, corticosteroids, high-dose megestrol acetate combination (Megace_H_Com) (400 mg/day), medroxyprogesterone, high-dose megestrol acetate (Megace_H) (400 mg/day), ghrelin mimetic and androgen analogues (Androgen) were significantly associated with MD of TBW of 6.45 (95% CI 2.45 to 10.45), 4.29 (95% CI 2.23 to 6.35), 3.18 (95% CI 0.94 to 5.41), 2.66 (95% CI 1.47 to 3.85), 1.73 (95% CI 0.27 to 3.20) and 1.50 (95% CI 0.56 to 2.44) kg. For appetite improvement, Megace_H_Com, Megace_H and Androgen significantly improved standardised APP score, compared with placebo. There is no significant difference in serious adverse events from all interventions compared with placebo.
CONCLUSIONS
Our findings suggest that several pharmacological interventions have potential to offer benefits in treatment of cachexia especially Megace_H and short-term use corticosteroids. Nonetheless, high-quality comparative studies to compare safety and efficacy are warranted for better management of cachexia.
Topics: Adrenal Cortex Hormones; Androgens; Appetite; Appetite Stimulants; Cachexia; Comparative Effectiveness Research; Drug Therapy, Combination; Gastrointestinal Agents; Ghrelin; Humans; Medroxyprogesterone; Megestrol Acetate; Minimal Clinically Important Difference; Neoplasms; Network Meta-Analysis; Randomized Controlled Trials as Topic; Terminal Care; Weight Gain
PubMed: 33246937
DOI: 10.1136/bmjspcare-2020-002601 -
Current Psychology (New Brunswick, N.J.) Jun 2022Anger and aggression have large impact on people's safety and the society at large. In order to provide an intervention to minimise aggressive behaviours, it is...
Anger and aggression have large impact on people's safety and the society at large. In order to provide an intervention to minimise aggressive behaviours, it is important to understand the neural and cognitive aspects of anger and aggression. In this systematic review, we investigate the cognitive and neural aspects of anger-related processes, including anger-related behaviours and anger reduction. Using this information, we then review prior existing methods on the treatment of anger-related disorders as well as anger management, including mindfulness and cognitive behavioural therapy. At the cognitive level, our review that anger is associated with excessive attention to anger-related stimuli and impulsivity. At the neural level, anger is associated with abnormal functioning of the amygdala and ventromedial prefrontal cortex. In conclusions, based on cognitive and neural studies, we here argue that mindfulness based cognitive behavioural therapy may be better at reducing anger and aggression than other behavioural treatments, such as cognitive behavioural therapy or mindfulness alone. We provide key information on future research work and best ways to manage anger and reduce aggression. Importantly, future research should investigate how anger related behaviours is acquired and how stress impacts the development of anger.
PubMed: 35693838
DOI: 10.1007/s12144-022-03143-6 -
Pain Physician Aug 2022Piriformis syndrome (PS) is a painful condition caused by entrapment of the sciatic nerve within the piriformis muscle. PS is typically unilateral and mainly occurs... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Piriformis syndrome (PS) is a painful condition caused by entrapment of the sciatic nerve within the piriformis muscle. PS is typically unilateral and mainly occurs related to entrapment of the sciatic nerve. Treatments include physiotherapy, analgesics, anti-inflammatory drugs, behavioral modifications, injection therapy with local anesthetics (LAs) and steroids, epidural injection, botulinum toxin (BT) injection, and surgery.
OBJECTIVES
To investigate the efficacy of BT, LA, and corticosteroid (CS) injections in relieving pain in patients affected by PS.
STUDY DESIGN
This systematic review and meta-analysis was conducted according to the "Cochrane Handbook for Systematic Reviews of Interventions" and the "Preferred Reporting Items for Systematic Reviews and Metaanalyses (PRISMA)" guidelines.
METHODS
A systematic search was conducted through PubMed, Cochrane, Web of Science, and Scopus through April 2021 for studies investigating the efficacy of BT, LA, or CS injection in improving pain in patients with PS. After screening retrieved studies, data were extracted from included studies and pooled. Overall results were reported as standardized mean difference (SMD) and 95% confidence interval (CI). Analysis was performed using RevMan software version 5.4.
RESULTS
Sixteen studies were included in this systematic review, and 12 of them were included in the quantitative synthesis. The pain scores decreased significantly after treatment with BT (SMD = -2.00; 95% CI [-2.84, -1.16], P < 0.001), LA and CS (SMD = -4.34; 95% CI [-5.77, 2.90], P < 0.001), LA (SMD = -3.73; 95% CI [-6.47, -0.99], P = 0.008), CS (SMD = -2.78; 95% CI [-3.56, -2.00], P < 0.001), and placebo injection (SMD = -0.04; 95% CI [-0.07, -0.01], P = 0.002). BT injection was less effective than LA and CS together (P = 0.006), more effective than placebo (P = 0.001), and similar to LA (P = 0.24) and CS (P = 0.18), when injected alone.
LIMITATIONS
A wide variety of study designs were utilized to obtain the largest sample size available. Many of the included studies lack randomization, and some are retrospective in nature. These limitations may introduce bias into the analyzed data and affect the results. Many studies had a low sample size and are of moderate quality, limiting the generalizability of the results. Also, we could not conduct a direct meta-analysis due to the lack of sufficient double-arm studies comparing different types of injection therapies.
CONCLUSIONS
In patients with PS, satisfactory pain improvement can be obtained by BT, LA plus CS, LA, or CS injection therapy. Injection of LA plus CS showed the best efficacy.
Topics: Adrenal Cortex Hormones; Anesthetics, Local; Botulinum Toxins; Humans; Piriformis Muscle Syndrome; Retrospective Studies
PubMed: 35901473
DOI: No ID Found -
International Journal of Molecular... Apr 2023Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the progressive loss of motor neurons in the spinal cord, brain stem, and... (Meta-Analysis)
Meta-Analysis Review
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the progressive loss of motor neurons in the spinal cord, brain stem, and cerebral cortex. Biomarkers for ALS are essential for disease detection and to provide information on potential therapeutic targets. Aminopeptidases catalyze the cleavage of amino acids from the amino terminus of protein or substrates such as neuropeptides. Since certain aminopeptidases are known to increase the risk of neurodegeneration, such mechanisms may reveal new targets to determine their association with ALS risk and their interest as a diagnostic biomarker. The authors performed a systematic review and meta-analyses of genome-wide association studies (GWASs) to identify reported aminopeptidases genetic loci associated with the risk of ALS. PubMed, Scopus, CINAHL, ISI Web of Science, ProQuest, LILACS, and Cochrane databases were searched to retrieve eligible studies in English or Spanish, published up to 27 January 2023. A total of 16 studies were included in this systematic review, where a series of aminopeptidases could be related to ALS and could be promising biomarkers (DPP1, DPP2, DPP4, LeuAP, pGluAP, and PSA/NPEPPS). The literature reported the association of single-nucleotide polymorphisms (SNPs: rs10260404 and rs17174381) with the risk of ALS. The genetic variation rs10260404 in the DPP6 gene was identified to be highly associated with ALS susceptibility, but meta-analyses of genotypes in five studies in a matched cohort of different ancestry (1873 cases and 1861 control subjects) showed no ALS risk association. Meta-analyses of eight studies for minor allele frequency (MAF) also found no ALS association for the "C" allele. The systematic review identified aminopeptidases as possible biomarkers. However, the meta-analyses for rs1060404 of DPP6 do not show a risk associated with ALS.
Topics: Humans; Amyotrophic Lateral Sclerosis; Aminopeptidases; Genome-Wide Association Study; Neurodegenerative Diseases; Prognosis; Biomarkers
PubMed: 37108335
DOI: 10.3390/ijms24087169 -
Neuroscience and Biobehavioral Reviews Jan 2021Previous imaging studies suggested that impairments of prefrontal-striatal and limbic circuits are correlated to excessive gambling. However, the neural underpinnings of... (Meta-Analysis)
Meta-Analysis Review
Previous imaging studies suggested that impairments of prefrontal-striatal and limbic circuits are correlated to excessive gambling. However, the neural underpinnings of gambling disorder (GD) continue to be the topic of debate. The present study aimed to identify structural changes in GD and differentiate the specific brain activity patterns associated with decision-making and reward-processing. We performed a systematic review complemented by Activation likelihood estimation (ALE) meta-analyses on morphometric and functional studies on neural correlates of GD. The ALE meta-analysis on structural studies revealed that patients with GD showed significant cortical grey-matter thinning in the right ventrolateral and ventromedial prefrontal cortex compared to healthy subjects. The ALE meta-analyses on functional studies revealed that patients with GD showed a significant hyperactivation in the medial prefrontal cortex and in the right ventral striatum during decision-making and gain processing compared to healthy subjects. These findings suggest that GD is related to an alteration of brain mechanisms underlying top-down control and appraisal of gambling-related stimuli and provided indications to develop new interventions in clinical practice.
Topics: Brain; Gambling; Humans; Likelihood Functions; Magnetic Resonance Imaging; Prefrontal Cortex; Reward; Ventral Striatum
PubMed: 33275954
DOI: 10.1016/j.neubiorev.2020.11.027 -
Brain Imaging and Behavior Oct 2022Medication overuse headache (MOH) is a prevalent secondary headache, bringing heavy economic burden and neuropsychological damage. Neuroimaging studies on the disease... (Meta-Analysis)
Meta-Analysis Review
Medication overuse headache (MOH) is a prevalent secondary headache, bringing heavy economic burden and neuropsychological damage. Neuroimaging studies on the disease reported divergent results. To merge the reported neuroimaging alterations in MOH patients and explore a pathophysiological mechanism of this disorder. A meta-analytic activation likelihood estimation (ALE) analysis method was used. We systematically searched English and Chinese databases for both morphological and functional neuroimaging studies published before Nov 18, 2021. Reported altered brain regions and the stereotactic coordinates of their peaks were extracted and pooled by GingerALE using Gaussian probability distribution into brain maps, illustrating converged regions of alteration among studies. We identified 927 articles, of which five studies on gray matter changes, using voxel-based morphometry (VBM) were eventually included for ALE analysis, with 344 subjects and 54 coordinates put into GingerALE. No functional magnetic resonance imaging (fMRI) or positron emission topography (PET) studies were included for pooling. Compared with healthy controls (HCs), MOH featured increased gray matter density in midbrain, striatum, cingulate, inferior parietal cortex and cerebellum (P < 0.001 uncorrected), whereas decreased gray matter density in orbitofrontal cortex (P < 0.05, family-wise error), frontal, insular and parietal cortices (P < 0.001 uncorrected). Withdrawal of analgesics led to decreased gray matter density in superior temporal gyrus, cuneus, midbrain and cerebellum (P < 0.001 uncorrected). This meta-analysis confirmed that medication overuse headache is associated with morphologic alteration in the reward system, the prefrontal cortex and a reversible modification in the pain network. Further functional imaging paradigms and longitudinal studies are required for a more definite conclusion and a causal mechanism.
Topics: Humans; Gray Matter; Likelihood Functions; Magnetic Resonance Imaging; Headache Disorders, Secondary; Brain; Headache
PubMed: 35143020
DOI: 10.1007/s11682-022-00634-9 -
Journal of Affective Disorders Jul 2023In this systematic review and meta-analysis, we aimed to provide a comprehensive overview of gray matter alterations of adult- and underage patients with posttraumatic... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
In this systematic review and meta-analysis, we aimed to provide a comprehensive overview of gray matter alterations of adult- and underage patients with posttraumatic stress disorder (PTSD) in comparison to healthy trauma-exposed (TC) and non-exposed (HC) individuals.
METHODS
We subdivided our groups into patients with PTSD after trauma exposure in adulthood (aa) or childhood (ac) as well as children with PTSD (cc). We identified 113 studies, including 6.800 participants in our review, which we divided into studies focusing on whole-brain and region-of-interest (ROI) analysis. We performed a coordinate-based meta-analysis on 14 studies in the group of aa-PTSD.
RESULTS
We and found lower gray matter volume in patients with PTSD (aa) in the medial frontal gyrus (PTSD
cortex (PTSD cortex, hippocampus, anterior cingulate cortex, insula, corpus callosum, and amygdala. LIMITATIONS
Due to a limited number of studies reporting whole-brain results, the meta-analyses could only be performed in one subgroup and within this subgroup for a limited number of studies.
CONCLUSIONS
Our results are in line with psychobiological models of PTSD that associate the identified regions with brain circuits involved in context processing, threat detection and emotion regulation.
Topics: Humans; Adult; Child; Gray Matter; Stress Disorders, Post-Traumatic; Magnetic Resonance Imaging; Cerebral Cortex; Brain
PubMed: 37086802
DOI: 10.1016/j.jad.2023.04.028