Theta burst stimulation for depression: a systematic review and network and pairwise meta-analysis.

In clinical practice, theta burst stimulation (TBS) presents as a more efficient and potentially more effective therapeutic modality than conventional repetitive transcranial magnetic stimulation (rTMS), as it allows for the delivery of more stimuli in less time and at similar intensities. To date, accelerated treatment plans according to various continuous (cTBS) and intermittent TBS (iTBS) protocols for depression have been proposed. To investigate which of the TBS protocols provided a favorable risk-benefit balance for individuals with depression, this systematic review and random-effects model network meta-analysis was conducted. The study outcomes included response rate (primary), depression symptom improvement, remission rate, all-cause discontinuation rate, incidence of switch to mania, and incidence of headache/discomfort at treatment site. In this meta-analysis, a total of 23 randomized controlled trials (n = 960, mean age = 41.88 years, with 60.78% females) were included. Approximately 69.57% of the trials included individuals with an exclusive diagnosis of major depressive disorder. The following six TBS protocols (target) were evaluated: cTBS (right-dorsolateral prefrontal cortex [R-DLPFC]), cTBS (R-DLPFC) + iTBS (left-DLPFC [L-DLPFC]), iTBS (L-DLPFC), iTBS (L-DLPFC) + iTBS (R-DLPFC), iTBS (left-dorsomedial prefrontal cortex) + iTBS (right-dorsomedial prefrontal cortex), and iTBS (occipital lobe). Compared to sham, cTBS (R-DLPFC) + iTBS (L-DLPFC), iTBS (L-DLPFC), and iTBS (occipital lobe) had a higher response rate (k = 23); cTBS (R-DLPFC) + iTBS (L-DLPFC) and iTBS (L-DLPFC) dominated in the depression symptom improvement (k = 23); and iTBS (L-DLPFC) had a higher remission rate (k = 15). No significant differences were found for all-cause discontinuation rate (k = 17), incidence of switch to mania (k = 7), and incidence of headache/discomfort at treatment site (k = 10) between any TBS protocols and sham. Thus, cTBS (R-DLPFC) + iTBS (L-DLPFC) and iTBS (L-DLPFC) demonstrate favorable risk-benefit balance for the treatment of depression.

White matter diffusion estimates in obsessive-compulsive disorder across 1653 individuals: machine learning findings from the ENIGMA OCD Working Group.

White matter pathways, typically studied with diffusion tensor imaging (DTI), have been implicated in the neurobiology of obsessive-compulsive disorder (OCD). However, due to limited sample sizes and the predominance of single-site studies, the generalizability of OCD classification based on diffusion white matter estimates remains unclear. Here, we tested classification accuracy using the largest OCD DTI dataset to date, involving 1336 adult participants (690 OCD patients and 646 healthy controls) and 317 pediatric participants (175 OCD patients and 142 healthy controls) from 18 international sites within the ENIGMA OCD Working Group. We used an automatic machine learning pipeline (with feature engineering and selection, and model optimization) and examined the cross-site generalizability of the OCD classification models using leave-one-site-out cross-validation. Our models showed low-to-moderate accuracy in classifying (1) "OCD vs. healthy controls" (Adults, receiver operator characteristic-area under the curve = 57.19 ± 3.47 in the replication set; Children, 59.8 ± 7.39), (2) "unmedicated OCD vs. healthy controls" (Adults, 62.67 ± 3.84; Children, 48.51 ± 10.14), and (3) "medicated OCD vs. unmedicated OCD" (Adults, 76.72 ± 3.97; Children, 72.45 ± 8.87). There was significant site variability in model performance (cross-validated ROC AUC ranges 51.6-79.1 in adults; 35.9-63.2 in children). Machine learning interpretation showed that diffusivity measures of the corpus callosum, internal capsule, and posterior thalamic radiation contributed to the classification of OCD from HC. The classification performance appeared greater than the model trained on grey matter morphometry in the prior ENIGMA OCD study (our study includes subsamples from the morphometry study). Taken together, this study points to the meaningful multivariate patterns of white matter features relevant to the neurobiology of OCD, but with low-to-moderate classification accuracy. The OCD classification performance may be constrained by site variability and medication effects on the white matter integrity, indicating room for improvement for future research.

Antidepressants for the treatment of adults with major depressive disorder in the maintenance phase: a systematic review and network meta-analysis.

A systematic review and random-effects model network meta-analysis were conducted to compare the efficacy, acceptability, tolerability, and safety of antidepressants to treat adults with major depressive disorder (MDD) in the maintenance phase. This study searched the PubMed, Cochrane Library, and Embase databases and included only double-blind, randomized, placebo-controlled trials with an enrichment design: patients were stabilized on the antidepressant of interest during the open-label study and then randomized to receive the same antidepressant or placebo. The outcomes were the 6-month relapse rate (primary outcome, efficacy), all-cause discontinuation (acceptability), discontinuation due to adverse events (tolerability), and the incidence of individual adverse events. The risk ratio with a 95% credible interval was calculated. The meta-analysis comprised 34 studies (n = 9384, mean age = 43.80 years, and %females = 68.10%) on 20 antidepressants (agomelatine, amitriptyline, bupropion, citalopram, desvenlafaxine, duloxetine, escitalopram, fluoxetine, fluvoxamine, levomilnacipran, milnacipran, mirtazapine, nefazodone, paroxetine, reboxetine, sertraline, tianeptine, venlafaxine, vilazodone, and vortioxetine) and a placebo. In terms of the 6-month relapse rate, amitriptyline, citalopram, desvenlafaxine, duloxetine, fluoxetine, fluvoxamine, mirtazapine, nefazodone, paroxetine, reboxetine, sertraline, tianeptine, venlafaxine, and vortioxetine outperformed placebo. Compared to placebo, desvenlafaxine, paroxetine, sertraline, venlafaxine, and vortioxetine had lower all-cause discontinuation; however, sertraline had a higher discontinuation rate due to adverse events. Compared to placebo, venlafaxine was associated with a lower incidence of dizziness, while desvenlafaxine, sertraline, and vortioxetine were associated with a higher incidence of nausea/vomiting. In conclusion, desvenlafaxine, paroxetine, venlafaxine, and vortioxetine had reasonable efficacy, acceptability, and tolerability in the treatment of adults with stable MDD.

Food go/no-go training alters neural circuits for food evaluation for appetite reduction.

Food go/no-go training has been traditionally categorized as a type of inhibitory training that decreases the desire for high-calorie food consumption. This training requires participants to either respond or withhold their responses to presented items with go cues or food items with no-go cues, respectively. Recent findings have suggested that this training may devalue food items associated with no-go cues instead of facilitating inhibitory control, leading to reduced food consumption. We thus hypothesized that food go/no-go training would alter the brain response to food items with no-go cues in food evaluation regions. To examine this hypothesis, we conducted a repeated measures functional magnetic resonance imaging using food images in healthy participants, who underwent 3 weeks of food go/no-go training (n = 26) using high- and low-calorie food items paired with no-go cues (no-go food) and go cues (go food), respectively, and control training (n = 24). The food go/no-go training reduced the ratings for the desire to eat no-go foods and increased the ratings for go foods. The reduction in no-go food rating was positively associated with a decrease in daily snack intake. The neural responses in the food evaluation regions increased for go foods. Moreover, the functional connectivity of those regions was altered. The food go/no-go training did not decrease impulsivity traits or increase restrained eating, which are associated with inhibitory control. Overall, food go/no-go training influenced the brain regions associated with food evaluation, thus devaluating no-go foods and reducing the daily snack intake. Accordingly, food go/no-go training could promote healthier food choices.

Pharmacological treatment for bipolar mania: a systematic review and network meta-analysis of double-blind randomized controlled trials.

A systematic review and random-effects model network meta-analysis was conducted to compare the efficacy, acceptability, tolerability, and safety of pharmacological interventions for adults with acute bipolar mania. We searched PubMed, the Cochrane Library, and Embase databases for eligible studies published before March 14, 2021. Randomized controlled trials (RCTs) of oral medication monotherapy lasting ≥10 days in adults with mania were included, and studies that allowed the use of antipsychotics as a rescue medication during a trial were excluded. The primary outcomes were response to treatment (efficacy) and all-cause discontinuation (acceptability). The secondary outcomes were the improvement of mania symptoms and discontinuation due to inefficacy. Of the 79 eligible RCTs, 72 double-blind RCTs of 23 drugs and a placebo were included in the meta-analysis (mean study duration = 3.96 ± 2.39 weeks, n = 16442, mean age = 39.55 years, with 50.93% males). Compared with the placebo, aripiprazole, asenapine, carbamazepine, cariprazine, haloperidol, lithium, olanzapine, paliperidone, quetiapine, risperidone, tamoxifen, valproate, and ziprasidone outperformed response to treatment (N = 56, n = 14503); aripiprazole, olanzapine, quetiapine, and risperidone had lower all-cause discontinuation; however, topiramate had higher all-cause discontinuation (N = 70, n = 16324). Compared with the placebo, aripiprazole, asenapine, carbamazepine, cariprazine, haloperidol, lithium, olanzapine, paliperidone, quetiapine, risperidone, tamoxifen, valproate, and ziprasidone outperformed the improvement of mania symptoms (N = 61, n = 15466), and aripiprazole, asenapine, carbamazepine, cariprazine, haloperidol, lithium, olanzapine, paliperidone, quetiapine, risperidone, valproate, and ziprasidone had lower discontinuation due to inefficacy (N = 50, n = 14284). In conclusions, these antipsychotics, carbamazepine, lithium, tamoxifen, and valproate were effective for acute mania. However, only aripiprazole, olanzapine, quetiapine, and risperidone had better acceptability than the placebo.

Mood stabilizers and/or antipsychotics for bipolar disorder in the maintenance phase: a systematic review and network meta-analysis of randomized controlled trials.

We searched Embase, PubMed, and CENTRAL from inception until 22 May 2020 to investigate which antipsychotics and/or mood stabilizers are better for patients with bipolar disorder in the maintenance phase. We performed two categorical network meta-analyses. The first included monotherapy studies and studies in which the two drugs used were specified (i.e., aripiprazole, aripiprazole once monthly, aripiprazole+lamotrigine, aripiprazole+valproate, asenapine, carbamazepine, lamotrigine, lamotrigine+valproate, lithium, lithium+oxcarbazepine, lithium+valproate, olanzapine, paliperidone, quetiapine, risperidone long-acting injection, valproate, and placebo). The second included studies on second-generation antipsychotic combination therapies (SGAs) (i.e., aripiprazole, lurasidone, olanzapine, quetiapine, and ziprasidone) with lithium or valproate (LIT/VAL) compared with placebo with LIT/VAL. Outcomes were recurrence/relapse rate of any mood episode (RR-any, primary), depressive episode (RR-dep) and manic/hypomanic/mixed episode (RR-mania), discontinuation, mortality, and individual adverse events. Risk ratios and 95% credible interval were calculated. Forty-one randomized controlled trials were identified (n = 9821; mean study duration, 70.5 ± 36.6 weeks; percent female, 54.1%; mean age, 40.7 years). All active treatments other than carbamazepine, lamotrigine+valproate (no data) and paliperidone outperformed the placebo for RR-any. Aripiprazole+valproate, lamotrigine, lamotrigine+valproate, lithium, olanzapine, and quetiapine outperformed placebo for RR-dep. All active treatments, other than aripiprazole+valproate, carbamazepine, lamotrigine, and lamotrigine+valproate, outperformed placebo for RR-mania. Asenapine, lithium, olanzapine, quetiapine, and valproate outperformed placebo for all-cause discontinuation. All SGAs+LIT/VALs other than olanzapine+LIT/VAL outperformed placebo+LIT/VAL for RR-any. Lurasidone+LIT/VAL and quetiapine+LIT/VAL outperformed placebo+LIT/VAL for RR-dep. Aripiprazole+LIT/VAL and quetiapine+LIT/VAL outperformed placebo+LIT/VAL for RR-mania. Lurasidone+LIT/VAL and quetiapine+LIT/VAL outperformed placebo+LIT/VAL for all-cause discontinuation. Treatment efficacy, tolerability, and safety profiles differed among treatments.

Hippocampal Functional Connectivity in Parkinson's Disease.

BACKGROUND: While the hippocampus is not part of the nigrostriatal dopaminergic pathway, influence of Parkinson's disease (PD) on the hippocampus has been consistently implicated. However, it is not clear how the hippocampal changes contribute to the pathology of PD. OBJECTIVES: We aimed to elucidate the physiological changes of the hippocampus in its orchestration with the rest of the brain. METHODS: Using the resting-state fMRI data from Parkinson's Progression Markers Initiative (PPMI), functional connectivity of the hippocampus was analyzed in 93 individuals with PD and 18 individuals without PD. RESULTS: A whole brain voxel-wise analysis showed that the bilateral paracingulate gyri were less connected to the hippocampus in the PD group compared to the control group. The hippocampus-paracingulate dysconnectivity did not show association with cognitive indices. CONCLUSIONS: The hippocampus in PD shows dysconnectivity to the paracingulate gyri.

Integrity of the cortico-spinal tract is associated with physical activity.

Background and purpose: Despite the primary motor efferent role of the cortico-spinal tract (CST), it is hardly understood whether the amount of physical activity is associated with the integrity of the CST.Materials and methods: We examined the association between the amount of physical activity and the integrity of the CST, using Diffusion Tensor Imaging (DTI) data from 465 individuals. The CST was segmented by probabilistic tractography and the association of the fractional anisotropy (FA) within was tested against physical activity (PA) assessed by moderate-intensity physical activity of the International Physical Activity Questionnaire.Results: The FA and PA showed a positive association. Post-hoc analyses showed that the radial diffusivity (RD) of the CST was negatively associated with PA, suggesting a potential association with preserved myelination with PA.Conclusion: This study shows that the integrity of the CST is associated with its traffic in the general population.

Estimation of Dynamic Bivariate Correlation Using a Weighted Graph Algorithm.

Dynamic correlation is the correlation between two time series across time. Two approaches that currently exist in neuroscience literature for dynamic correlation estimation are the sliding window method and dynamic conditional correlation. In this paper, we first show the limitations of these two methods especially in the presence of extreme values. We present an alternate approach for dynamic correlation estimation based on a weighted graph and show using simulations and real data analyses the advantages of the new approach over the existing ones. We also provide some theoretical justifications and present a framework for quantifying uncertainty and testing hypotheses.

Association of cardiorespiratory fitness on interhemispheric hippocampal and parahippocampal functional connectivity.

Interhemispheric functional connectivity is associated with cognitive functioning. Although previous work has evaluated the association of cardiorespiratory fitness on cognitive function, there has been a limited investigation of the association of cardiorespiratory fitness on the functional connectivity of memory-related brain structures. As such, the objective of this study was to examine the association between cardiorespiratory fitness and parahippocampal and hippocampal interhemispheric functional connectivity. Data from the Nathan Kline Institute-Rockland Sample (NKI-RS) were utilized. Our analysis consisted of 284 participants (Mage  = 43 years; 62% female). Cardiorespiratory fitness was objectively measured using a cycle ergometer protocol. Parahippocampal and hippocampal interhemispheric functional connectivity were assessed from fMRI. Higher cardiorespiratory fitness was associated with greater parahippocampal (ß = 0.004; CI, 0.00009 to 0.008, p = 0.04), but not hippocampal (ß = 0.001; CI, -0.002 to 0.005, p = 0.44) interhemispheric functional connectivity. In conclusion, enhanced cardiorespiratory fitness may facilitate parahippocampal interhemispheric functional connectivity.

Effect of discontinuation v. maintenance of antipsychotic medication on relapse rates in patients with remitted/stable first-episode psychosis: a meta-analysis.

BACKGROUND: Discontinuation of antipsychotics predisposes patients with remitted/stable first-episode psychosis (FEP) to a higher risk of relapse, but it remains unclear how long discontinuation increases the relapse rate in these patients compared with maintenance. METHODS: This meta-analysis of randomized controlled trials (RCTs) compared relapse rates in FEP patients between antipsychotic treatment discontinuation and maintenance groups at 1, 2, 3, 6, 9, 12 (primary), and 18-24 months. The risk ratio (RR) and numbers needed to treat/harm (NNT/NNH) were calculated using a random-effects model. RESULTS: Ten RCTs were identified (n = 776; mean study duration, 18.6 ± 6.0 months). The antipsychotics were discontinued abruptly in four RCTs (which reported data only at 12 months) and after tapering off gradually over several months (mean length, 3 months) in six RCTs. Compared with the discontinuation group, the maintenance group experienced significantly fewer relapses at all time points except 1 month [RR (NNT): 2 months, 0.49 (13); 3 months, 0.46 (9); 6 months, 0.55 (6); 9 months, 0.48 (3); 12 months, 0.47 (3); and 18-24 months, 0.57 (4)]. The maintenance group was associated with higher discontinuation due to adverse events (RR, 2.61; NNH, not significant). CONCLUSIONS: Maintaining antipsychotic treatment prevented relapse for up to 24 months in FEP patients. Discontinuation of antipsychotics for ⩾2 months significantly increased the risk of relapse. However, 45.7% of patients who discontinued antipsychotics for 12 months (39.4% after 18-24 months) did not experience a relapse.

Anti-Dementia Drugs for Psychopathology and Cognitive Impairment in Schizophrenia: A Systematic Review and Meta-Analysis.

BACKGROUND: We conducted a systematic review and meta-analysis of double-blind, randomized, placebo-controlled trials of anti-dementia drugs plus antipsychotics for schizophrenia. METHODS: Primary outcomes of efficacy and safety included improving overall symptoms (Positive and Negative Syndrome Scale and Brief Psychiatric Rating Scale scores) and all-cause discontinuation, respectively. Other outcomes included psychopathology subscales (positive, negative, general, and anxiety/depressive symptoms), cognitive function (attention/vigilance, reasoning/problem solving, social cognition, speed of processing, verbal learning, visual learning, working memory, and cognitive control/executive function), Mini-Mental State Examination scores, treatment discontinuation due to adverse events and inefficacy, and individual adverse events. We evaluated the effect size using a random effects model. RESULTS: We identified 37 studies (n=1574): 14 donepezil-based (n=568), 10 galantamine-based (n=371), 4 rivastigmine-based (n=146), and 9 memantine-based (n=489) studies. Pooled anti-dementia drugs plus antipsychotics treatments were superior to placebo plus antipsychotics in improving the overall symptoms (24 studies, 1069 patients: standardized mean difference=-0.34, 95% CI=-0.61 to -0.08, P=.01), negative symptoms (24 studies, 1077 patients: standardized mean difference =-0.62, 95% CI=-0.92 to -0.32, Pcorrected=.00018), and Mini-Mental State Examination scores (7 studies, 225 patients: standardized mean difference=-0.79, 95% CI=-1.23 to -0.34, P=.0006). No significant differences were found between anti-dementia drugs plus antipsychotics and placebo plus antipsychotics regarding other outcomes. CONCLUSIONS: Although the results suggest that anti-dementia drugs plus antipsychotics treatment improves negative symptoms and Mini-Mental State Examination scores in schizophrenia patients, they possibly were influenced by a small-study effect and some bias. However, it was not superior to placebo plus antipsychotics in improving composite cognitive test score, which more systematically evaluates cognitive impairment than the Mini-Mental State Examination score. Overall, the anti-dementia drugs plus antipsychotics treatment was well tolerated.

Disrupted Olfactory Integration in Schizophrenia: Functional Connectivity Study.

Background: Evidence for olfactory dysfunction in schizophrenia has been firmly established. However, in the typical understanding of schizophrenia, olfaction is not recognized to contribute to or interact with the illness. Despite the solid presence of olfactory dysfunction in schizophrenia, its relation to the rest of the illness remains largely unclear. Here, we aimed to examine functional connectivity of the olfactory bulb, olfactory tract, and piriform cortices and isolate the network that would account for the altered olfaction in schizophrenia. Methods: We examined the functional connectivity of these specific olfactory regions in order to isolate other brain regions associated with olfactory processing in schizophrenia. Using the resting state functional MRI data from the Center for Biomedical Research Excellence in Brain Function and Mental Illness, we compared 84 patients of schizophrenia and 90 individuals without schizophrenia. Results: The schizophrenia group showed disconnectivity between the anterior piriform cortex and the nucleus accumbens, between the posterior piriform cortex and the middle frontal gyrus, and between the olfactory tract and the visual cortices. Conclusions: The current results suggest functional disconnectivity of olfactory regions in schizophrenia, which may account for olfactory dysfunction and disrupted integration with other sensory modalities in schizophrenia.

Systematic review and meta-analysis reveals acutely elevated plasma cortisol following fasting but not less severe calorie restriction.

Elevated plasma cortisol has been reported following caloric restriction, and may contribute to adverse effects including stress-induced overeating, but results from published studies are inconsistent. To clarify the effects of caloric restriction on plasma cortisol, and to assess cortisol as an indicator of stress during caloric restriction, we conducted a systematic review and meta-analysis of published studies in which cortisol was measured following caloric restriction without other manipulations in humans. We further compared effects of fasting, very low calorie diet (VLCD), and other less intense low calorie diet (LCD), as well as the duration of caloric restriction by meta-regression. Overall, caloric restriction significantly increased serum cortisol level in 13 studies (357 total participants). Fasting showed a very strong effect in increasing serum cortisol, while VLCD and LCD did not show significant increases. The meta-regression analysis showed a negative association between the serum cortisol level and the duration of caloric restriction, indicating serum cortisol is increased in the initial period of caloric restriction but decreased to the baseline level after several weeks. These results suggest that severe caloric restriction causes activation of the hypothalamic-pituitary-adrenal axis, which may be transient, but results in elevated cortisol which could mediate effects of starvation on brain and metabolic function as well as ameliorate weight loss.

Brain white matter development is associated with a human-specific haplotype increasing the synthesis of long chain fatty acids.

The genetic and molecular pathways driving human brain white matter (WM) development are only beginning to be discovered. Long chain polyunsaturated fatty acids (LC-PUFAs) have been implicated in myelination in animal models and humans. The biosynthesis of LC-PUFAs is regulated by the fatty acid desaturase (FADS) genes, of which a human-specific haplotype is strongly associated with ω-3 and ω-6 LC-PUFA concentrations in blood. To investigate the relationship between LC-PUFA synthesis and human brain WM development, we examined whether this FADS haplotype is associated with age-related WM differences across the life span in healthy individuals 9-86 years of age (n = 207). Diffusion tensor imaging was performed to measure fractional anisotropy (FA), a putative measure of myelination, of the cerebral WM tracts. FADS haplotype status was determined with a single nucleotide polymorphism (rs174583) that tags this haplotype. Overall, normal age-related WM differences were observed, including higher FA values in early adulthood compared with childhood, followed by lower FA values across older age ranges. However, individuals homozygous for the minor allele (associated with lower LC-PUFA concentrations) did not display these normal age-related WM differences (significant age × genotype interactions, p(corrected) < 0.05). These findings suggest that LC-PUFAs are involved in human brain WM development from childhood into adulthood. This haplotype and LC-PUFAs may play a role in myelin-related disorders of neurodevelopmental origin.

The accumbofrontal tract: Diffusion tensor imaging characterization and developmental change from childhood to adulthood.

The presence of an anatomical connection between the orbitofrontal cortex and ventral striatum, forming a so-called reward network, is well established across species. This connection has important implications for reward processing and is relevant to a number of neuropsychiatric disorders. Moreover, white matter (WM) is known to continue to mature across adolescence and into early adulthood, and developmental change in the reward network is an important component of models of decision making and risk taking. Despite the importance of this connection, the underlying WM has only recently been characterized in humans histologically, and not yet in-vivo using brain imaging. Here, we implemented diffusion tensor imaging (DTI) in a large cross-sectional sample of 295 healthy individuals ages 8-68 to further characterize the WM of this connection and its development from childhood into adulthood. We demonstrate that the accumbofrontal tract, connecting the orbitofrontal cortex and nucleus accumbens, can be identified using standard DTI sequences. Using Poisson modeling, we show that the accumbofrontal tract undergoes significant change across the lifespan, with males showing a higher and earlier peak compared to females. Moreover, the change occurs in a pattern consistent with developmental models of decision-making. These findings support the hypothesis that developmental differences in WM integrity may be a contributing factor to the observed risk taking that occurs in adolescence. The accumbofrontal tract is not yet included in standard WM atlases, but may be important for inclusion in studies investigating fronto-striatal networks, as well as in investigations of substance abuse and decision making.