A systematic review of network meta-analyses for pharmacological treatment of common mental disorders

New insights into the involvement of serotonin and BDNF-TrkB signalling in cannabidiol's antidepressant effect

Cannabidiol (CBD) is a phytocannabinoid devoid of psychostimulant properties and is currently under investigation as a potential antidepressant drug. However, the mechanisms underlying CBD's antidepressant effects are not yet well understood. CBD targets include a variety of receptors, enzymes, and transporters, with different binding-affinities. Neurochemical and pharmacological evidence indicates that both serotonin and BDNF-TrkB signalling in the prefrontal cortex are necessary for the antidepressant effects induced by CBD in animal models. Herein, we reviewed the current literature to dissect if these are independent mechanisms or if CBD-induced modulation of the serotonergic neurotransmission could mediate its neuroplastic effects through subsequent regulation of BDNF-TrkB signalling, thus culminating in rapid neuroplastic changes. It is hypothesized that: a) CBD interaction with serotonin receptors on neurons of the dorsal raphe nuclei and the resulting disinhibition of serotonergic neurons would promote rapid serotonin release in the PFC and hence its neuroplastic and antidepressant effects; b) CBD facilitates BDNF-TRKB signalling, especially in the PFC, which rapidly triggers neurochemical and neuroplastic effects. These hypotheses are discussed with perspectives for new drug development and clinical applications.

Transitivity, coherence, and reliability of network meta-analyses comparing proximal humerus fracture treatments: a meta-epidemiological study

BACKGROUND

Network meta-analyses can be valuable for decision-makers in guiding clinical practice. However, for network meta-analysis results to be reliable, the assumptions of both transitivity and coherence must be met, and the methodology should adhere to current best practices. We aimed to assess whether network meta-analyses of randomized controlled trials (RCTs) comparing interventions for proximal humerus fractures provide reliable estimates of intervention effects.

METHODS

We searched PubMed, EMBASE, The Cochrane Library, and Web of Science for network meta-analyses comparing interventions for proximal humerus fractures. We critically assessed the methodology regarding the development of a protocol, search strategy, trial inclusion, outcome extraction, and the methods used to conduct the network meta-analyses. We assessed the transitivity and coherence of the network graphs for the Constant score (CS), Disabilities of the Arm, Shoulder, and Hand score (DASH), and additional surgery. Transitivity was assessed by comparing probable effect modifiers (age, gender, fracture morphology, and comorbidities) across intervention comparisons. Coherence was assessed using Separating Indirect from Direct Evidence (SIDE) (Separating Indirect from Direct Evidence) and the design-by-treatment interaction test. We used CINeMA (Confidence in Network Meta-analyses) to assess the confidence in the results.

RESULTS

None of the three included network meta-analyses had a publicly available protocol or data-analysis plan, and they all had methodological flaws that could threaten the validity of their results. Although we did not detect incoherence for most comparisons, the transitivity assumption was violated for CS, DASH, and additional surgery in all three network meta-analyses. Additionally, the confidence in the results was 'very low' primarily due to within-study bias, reporting bias, intransitivity, imprecision, and heterogeneity.

CONCLUSIONS

Current network meta-analyses of RCTs comparing interventions for proximal humerus fractures do not provide reliable estimates of intervention effects. We advise caution in using these network meta-analyses to guide clinical practice. To improve the utility of network meta-analyses to guide clinical practice, journal editors should require that network meta-analyses are done according to a predefined analysis plan in a publicly available protocol and that both coherence and transitivity have been adequately assessed and reported.

Antidepressant use during pregnancy and the risk for gestational diabetes: a systematic review and meta-analysis

OBJECTIVE

Antidepressant medications are used by increasing numbers of pregnant women. The evidence on the relationship between antidepressant use during pregnancy and the risk for gestational diabetes mellitus (GDM) is inconsistent. We perform a systematic review and meta-analysis to assess the GDM risk associated with antidepressant exposure during pregnancy.

METHODS

We systematically searched the PubMed and EMBASE databases until December 2021. We sought observational studies assessing the association between gestational antidepressant use and GDM.

RESULTS

Five observational studies were included in the analysis. Mothers exposed to antidepressants during pregnancy were at a significantly increased risk for GDM (relative risk [RR] 1.20, 95% confidence interval [CI] 1.11-1.30; p < .001). However, after considering confounding by indication, we observed no significant effect of antidepressant use during pregnancy on the risk of GDM (RR 1.13, 95% CI 1-1.28; p = .054; I² = 0%). Independent of clinical indication, subgroup analysis based on individual antidepressants suggested that the risk was increased by venlafaxine or amitriptyline use, but not by selective serotonin reuptake inhibitors.

CONCLUSIONS

The significant association between antidepressant exposure during pregnancy and GDM may be overestimated due to confounding by indication. However, the evidence remains insufficient, particularly for specific drug classes.

[Combination of ketamine and esketamine with Exposure and Response Prevention (ERP) therapy for Obsessive-Compulsive Disorder]

Obsessive-Compulsive Disorder (OCD), characterized by the combination of obsession and compulsion, is a clinical and therapeutic challenge. Many patients with OCD do not respond to first-line treatments such as serotonin selective reuptake inhibitors (SSRIs) and exposure and response prevention psychotherapy (ERP). For these resistant patients, some preliminary studies have shown that ketamine, a non-selective glutamatergic NMDA receptors antagonist, could improve the obsessive symptoms. A number of these studies have also suggested that the combination of ketamine with ERP psychotherapy may jointly potentiate the effectiveness of ketamine and ERP. In this paper, we present the existing data on the combined use of ketamine with ERP psychotherapy for OCD. We suggest that modulation of NMDA receptor activity and glutamatergic signaling by ketamine may promote the therapeutic mechanisms involved in ERP such as fear extinction and brain plasticity mechanisms. Finally, we propose a ketamine-augmented ERP psychotherapy (KAP-ERP) protocol in OCD, and we present the limitations associated with its application in clinical practice.

The future of psychopharmacology: a critical appraisal of ongoing phase 2/3 trials, and of some current trends aiming to de-risk trial programmes of novel agents

Despite considerable progress in pharmacotherapy over the past seven decades, many mental disorders remain insufficiently treated. This situation is in part due to the limited knowledge of the pathophysiology of these disorders and the lack of biological markers to stratify and individualize patient selection, but also to a still restricted number of mechanisms of action being targeted in monotherapy or combination/augmentation treatment, as well as to a variety of challenges threatening the successful development and testing of new drugs. In this paper, we first provide an overview of the most promising drugs with innovative mechanisms of action that are undergoing phase 2 or 3 testing for schizophrenia, bipolar disorder, major depressive disorder, anxiety and trauma-related disorders, substance use disorders, and dementia. Promising repurposing of established medications for new psychiatric indications, as well as variations in the modulation of dopamine, noradrenaline and serotonin receptor functioning, are also considered. We then critically discuss the clinical trial parameters that need to be considered in depth when developing and testing new pharmacological agents for the treatment of mental disorders. Hurdles and perils threatening success of new drug development and testing include inadequacy and imprecision of inclusion/exclusion criteria and ratings, sub-optimally suited clinical trial participants, multiple factors contributing to a large/increasing placebo effect, and problems with statistical analyses. This information should be considered in order to de-risk trial programmes of novel agents or known agents for novel psychiatric indications, increasing their chances of success.

Neuropharmacology Potential of the Hydroalcoholic Extract from the Leaves of Piper cernuum: Anxiolytic, Hypnotic, and Antidepressant-Like Effects

Aim

The use of medicinal plants in the treatment of mental illnesses is a reality that accompanies the history of civilizations, and the Piper genus exhibits many species with pharmacologically proven central effects. Then, this study evaluated the neuropharmacological effects of the hydroalcoholic extract from Piper cernuum (HEPC) leaves to validate its uses in folk medicine.

Materials and Methods

Primarily Swiss mice (female, 25-30 g) were pretreated with HEPC (50-150 mg/kg, p.o.), vehicle, or the positive control, and submitted to open-field test (OFT), inhibitory avoidance test (IAT), tail suspension test (TST), and forced swim test (FST). Also, mice were exposed to pentylenetetrazol- and strychnine-induced seizure assay, pentobarbital-induced hypnosis test, and elevated plus-maze (EPM). The GABA levels and MAO-A activity were measured in the animal's brain after 15 days of HEPC administration (150 mg/kg, p.o.).

Results

Mice pretreated with HEPC (100 and 150 mg/kg) and exposed to pentobarbital presented decreased sleep latency and increased sleep duration (HEPC 150 mg/kg). In EPM, the HEPC (150 mg/kg) increased the frequency of entry and the time of exploration of mice in the open arms. The antidepressant-like properties of HEPC were demonstrated by the decrease in the mice's immobility time when tested in FST and TST. The extract did not show anticonvulsant activity, in addition to not improving the memory parameters of animals (IAT) or interfering with their locomotor activity (OFT). Besides, HEPC administration decreased the MAO-A activity and increased the GABA levels in the animal's brain.

Conclusion

HEPC induces sedative-hypnotic, anxiolytic-, and antidepressant-like effects. These neuropharmacological effects of HEPC could be, at least in part, related to the modulation of the GABAergic system and/or MAO-A activity.

Critical evaluation of reporting quality of network meta-analyses assessing the effectiveness of acupuncture

BACKGROUND

and purpose: Network meta-analyses (NMAs) comparing the effectiveness of multiple acupuncture have been published but the key concepts underlying NMAs have not been properly reported. This critical evaluation aims to assess the completeness of reporting for NMAs of acupuncture to enhance the validity of findings.

MATERIALS AND METHODS

Five databases were searched. The characteristics and reporting quality based on the Preferred Reporting Items for Systematic Reviews and Meta-analyses Extension Statement for reporting of NMA (PRISMA-NMA) were evaluated. NMAs were categorized into two groups according to the publication date, reporting guideline, and intervention. The group differences and correlation coefficients were calculated.

RESULTS

Forty-two NMAs of acupuncture were evaluated. The reporting quality for new items in the key concepts of NMAs was low (median 70.0 % (interquartile range 60.0-80.0)). While the issue of consistency was well reported, the assumption of transitivity and network geometry showed poor reporting. Seventeen studies that followed the PRISMA-NMA guideline showed a higher reporting rate for essential concepts of NMA. The recency of publication did not guarantee clear reporting.

CONCLUSION

The reporting quality of NMAs of acupuncture was low. The researchers should follow the guidelines on the reporting of NMAs.

Selective serotonin reuptake inhibitors, and serotonin and norepinephrine reuptake inhibitors for anxiety, obsessive-compulsive, and stress disorders: A 3-level network meta-analysis

BACKGROUND

Anxiety, obsessive-compulsive, and stress-related disorders frequently co-occur, and patients often present symptoms of several domains. Treatment involves the use of selective serotonin reuptake inhibitors (SSRIs) and serotonin and norepinephrine reuptake inhibitors (SNRIs), but data on comparative efficacy and acceptability are lacking. We aimed to compare the efficacy of SSRIs, SNRIs, and placebo in multiple symptom domains in patients with these diagnoses over the lifespan through a 3-level network meta-analysis.

METHODS AND FINDINGS

We searched for published and unpublished randomized controlled trials that aimed to assess the efficacy of SSRIs or SNRIs in participants (adults and children) with diagnosis of any anxiety, obsessive-compulsive, or stress-related disorder in MEDLINE, PsycINFO, Embase, and Cochrane Library from inception to 23 April 2015, with an update on 11 November 2020. We supplemented electronic database searches with manual searches for published and unpublished randomized controlled trials registered in publicly accessible clinical trial registries and pharmaceutical companies' databases. No restriction was made regarding comorbidities with any other mental disorder, participants' age and sex, blinding of participants and researchers, date of publication, or study language. The primary outcome was the aggregate measure of internalizing symptoms of these disorders. Secondary outcomes included specific symptom domains and treatment discontinuation rate. We estimated standardized mean differences (SMDs) with 3-level network meta-analysis with random slopes by study for medication and assessment instrument. Risk of bias appraisal was performed using the Cochrane Collaboration's risk of bias tool. This study was registered in PROSPERO (CRD42017069090). We analyzed 469 outcome measures from 135 studies (n = 30,245). All medications were more effective than placebo for the aggregate measure of internalizing symptoms (SMD -0.56, 95% CI -0.62 to -0.51, p < 0.001), for all symptom domains, and in patients from all diagnostic categories. We also found significant results when restricting to the most used assessment instrument for each diagnosis; nevertheless, this restriction led to exclusion of 72.71% of outcome measures. Pairwise comparisons revealed only small differences between medications in efficacy and acceptability. Limitations include the moderate heterogeneity found in most outcomes and the moderate risk of bias identified in most of the trials.

CONCLUSIONS

In this study, we observed that all SSRIs and SNRIs were effective for multiple symptom domains, and in patients from all included diagnostic categories. We found minimal differences between medications concerning efficacy and acceptability. This three-level network meta-analysis contributes to an ongoing discussion about the true benefit of antidepressants with robust evidence, considering the significantly larger quantity of data and higher statistical power when compared to previous studies. The 3-level approach allowed us to properly assess the efficacy of these medications on internalizing psychopathology, avoiding potential biases related to the exclusion of information due to distinct assessment instruments, and to explore the multilevel structure of transdiagnostic efficacy.

Perceived barriers, benefits and correlates of physical activity in outpatients with Major Depressive Disorder: A study from Brazil

OBJECTIVES

To evaluate the barriers, benefits and correlates of physical activity (PA) in outpatients with Major Depressive Disorder (MDD).

METHODS

Data were collected from outpatients under treatment for MDD at Hospital de Clínicas de Porto Alegre. Barriers and benefits were assessed with the Exercise Barriers/Benefits Scale (EBBS). Objective and self-reported PA were assessed with pedometers and the International Physical Activity Questionnaire (IPAQ), respectively.

RESULTS

The sample consisted of 65 outpatients (82% female; mean age = 50.9 years; SD = 10.1). Improvement in physical performance was the most reported benefit (mean = 3.00; SD = 0.3) while the most reported barrier was physical exertion (mean = 2.95; SD = 0.4). Depression symptom severity was negatively correlated with life enhancement (r = -0.337; p = 0.009), physical performance (r=-0.348; p = 0.007), psychological outlook (r=-0.364; p = 0.005), social interaction (r=-0.317; p = 0.015) and preventive health (r=-0.352; p = 0.007).

CONCLUSION

Physical exertion is the most perceived barrier for PA in people with MDD. Symptom severity is associated with higher barrier levels, whilst higher current PA levels are associated with more benefits and lesser barriers. Interventions targeting PA promotion should consider the identified benefits and barriers when developing PA programs for people with MDD in outpatient settings.

Role of glucocorticoid- and monoamine-metabolizing enzymes in stress-related psychopathological processes

Glucocorticoid signaling is fundamental in healthy stress coping and in the pathophysiology of stress-related diseases, such as post-traumatic stress disorder (PTSD). Glucocorticoids are metabolized by cytochrome P450 (CYP) as well as 11-β-hydroxysteroid dehydrogenase type 1 (11βHSD1) and 2 (11βHSD2). Acute stress-induced increase in glucocorticoid concentrations stimulates the expression of several CYP sub-types. CYP is primarily responsible for glucocorticoid metabolism and its increased activity can result in decreased circulating glucocorticoids in response to repeated stress stimuli. In addition, repeated stress-induced glucocorticoid release can promote 11βHSD1 activation and 11βHSD2 inhibition, and the 11βHSD2 suppression can lead to apparent mineralocorticoid excess. The activation of CYP and 11βHSD1 and the suppression of 11βHSD2 may at least partly contribute to development of the blunted glucocorticoid response to stressors characteristic in high trait anxiety, PTSD, and other stress-related disorders. Glucocorticoids and glucocorticoid-metabolizing enzymes interact closely with other biomolecules such as inflammatory cytokines, monoamines, and some monoamine-metabolizing enzymes, namely the monoamine oxidase type A (MAO-A) and B (MAO-B). Glucocorticoids boost MAO activity and this decreases monoamine levels and induces oxidative tissue damage which then activates inflammatory cytokines. The inflammatory cytokines suppress CYP expression and activity. This dynamic cross-talk between glucocorticoids, monoamines, and their metabolizing enzymes could be a critical factor in the pathophysiology of stress-related disorders.Lay summaryGlucocorticoids, which are produced and released under the control by brain regulatory centers, are fundamental in the stress response. This review emphasizes the importance of glucocorticoid metabolism and particularly the interaction between the brain and the liver as the major metabolic organ in the body. The activity of enzymes involved in glucocorticoid metabolism is proposed to play not only an important role in positive, healthy glucocorticoid effects, but also to contribute to the development and course of stress-related diseases.

Valproate for acute mania

BACKGROUND

Bipolar disorder is a severe and common mental disorder where patients experience recurrent symptoms of elevated or irritable mood, depression, or a combination of both. Treatment is usually with psychiatric medication, including mood stabilisers, antidepressants and antipsychotics. Valproate is an effective maintenance treatment for bipolar disorder. However, evidence assessing the efficacy of valproate in the treatment of acute mania is less robust, especially when comparing it to some of the newer antipsychotic agents. This review is an update of a previous Cochrane Review (last published 2003) on the role of valproate in acute mania.

OBJECTIVES

To assess the efficacy and tolerability of valproate for acute manic episodes in bipolar disorder compared to placebo, alternative pharmacological treatments, or a combination pharmacological treatments, as measured by the treatment of symptoms on specific rating scales for individual episodes in paediatric, adolescent and adult populations.

SEARCH METHODS

We searched Ovid MEDLINE (1950- ), Embase (1974- ), PsycINFO (1967- ) and the Cochrane Central Register of Controlled Trials (CENTRAL) to 28 September 2018. We had also conducted an earlier search of these databases in the Cochrane Common Mental Disorders Controlled Trials Register (CCMDCTR) (all years to 6 June 2016). We also searched the World Health Organization (WHO) trials portal (ICTRP) and clinicaltrials.gov in September 2018, to identify any additional unpublished or ongoing studies.

SELECTION CRITERIA

Single- and double-blind, randomised controlled trials comparing valproate with placebo, alternative antimanic treatments, or a combination of pharmacological treatments. We also considered studies where valproate was used as an adjunctive treatment in combination with another agent separately from studies where it was used in monotherapy. We included male and female patients of all ages and ethnicity with bipolar disorder.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed data extraction and methodological quality assessment. For analysis, we used the odds ratio (OR) for binary efficacy outcomes and the mean difference (MD) or standardised mean difference (SMD) for continuously distributed outcomes.

MAIN RESULTS

Twenty-five trials (3252 participants) compared valproate with either placebo or alternative antimanic treatments to alleviate the symptoms of acute mania. For efficacy, our primary outcome was response rate. For tolerability, our primary outcome was the number of participants with any adverse effect. This meta-analysis included studies focusing on children, adolescents, as well as adults with a range of severity of manic symptoms. The majority of studies focused on adult men and women (aged 18 and above), were conducted in inpatient settings and completed in the US. Five studies in this review focused on children and adolescents (aged 18 and under) so that the review covers an age range from 3 - 82 years. Seven studies contained outpatient participants in some form. Nine studies included data that has been collected outside the US, namely Iran (4 studies), India (3 studies), China (1 study), or across several international countries (1 study).In adults, high-quality evidence found that valproate induces a slightly higher response compared to placebo (45% vs 29%, OR 2.05, 95% CI 1.32 to 3.20; 4 studies, 869 participants). Moderate-quality evidence found there was probably little or no difference in response rates between valproate and lithium (56% vs 62%, OR 0.80, 95% CI 0.48 to 1.35; 3 studies, 356 participants). In adults, low-quality evidence found there may be little or no difference in response rate between valproate and olanzapine (38% vs 44%, OR 0.77, 95% CI 0.48 to 1.25; 2 studies, 667 participants).In the children and adolescent population, the evidence regarding any difference in response rates between valproate and placebo was uncertain (23% vs 22%, OR 1.11, 95% CI 0.51 to 2.38; 1 study, 151 participants, very low-quality evidence). Low-quality evidence found that the response rate of participants receiving valproate may be lower compared to risperidone (23% vs 66%, OR 0.16, 95% CI 0.08 to 0.29; 1 study, 197 participants). The evidence regarding any difference in response rates between valproate and lithium was uncertain (23% vs 34%, OR 0.57, 95% CI 0.31 to 1.07; 1 study, 197 participants, very low-quality evidence).In terms of tolerability in adults, moderate-quality evidence found that there are probably more participants receiving valproate who experienced any adverse events compared to placebo (83% vs 75%, OR 1.63, 95% CI 1.13 to 2.36; 3 studies, 745 participants). Low-quality evidence found there may be little or no difference in tolerability between valproate and lithium (78% vs 86%, OR 0.61, 95% CI 0.25 to 1.50; 2 studies, 164 participants). We did not obtain primary tolerability outcome data on the olanzapine comparison.Within the children and adolescent population, the evidence regarding any difference between valproate or placebo was uncertain (67% vs 60%, OR 1.39, 95% CI 0.71 to 2.71; 1 study, 150 participants, very low-quality evidence). We did not obtain primary tolerability outcome data on the lithium or risperidone comparisons.

AUTHORS' CONCLUSIONS

There is evidence that valproate is an efficacious treatment for acute mania in adults when compared to placebo. By contrast, there is no evidence of a difference in efficacy between valproate and placebo for children and adolescents. Valproate may be less efficacious than olanzapine in adults, and may also be inferior to risperidone as a monotherapy treatment for paediatric mania. Generally, there is uncertain evidence regarding whether valproate causes more or less side effects than the other main antimanic therapies. However, evidence suggests that valproate causes less weight gain and sedation than olanzapine.

The evidence for physical activity in the management of major mental illnesses: a concise overview to inform busy clinicians' practice and guide policy

PURPOSE OF REVIEW

Physical activity has established the efficacy in improving physical health, mental health and cognition in the general population. Recent research has examined its potential as a preventive measure and/or adjunctive treatment for various mental health conditions. This review summarizes the recent evidence for physical activity in the management of major mental illnesses.

RECENT FINDINGS

Emerging evidence suggests that physical activity may confer protection against depression and anxiety/stress disorders. There is robust evidence that structured and supervised physical activity, including aerobic and resistance training, can improve multiple outcomes in major depression, pre/postnatal depression, anxiety/stress disorders and schizophrenia. Emerging evidence suggests a potential role for physical activity in bipolar disorder and alcohol use disorders.

SUMMARY

The quantity and quality of evidence regarding the efficacy of physical activity for mental illnesses is increasing. Given the established and further potential benefits and low adverse risk profile, physical activity should be offered as an adjunctive part of core mental health treatment. However, there is a need for high-quality multisite randomized controlled trials that can be replicated in routine care in mental health services. Future population-level trials are needed to examine the potential use of physical activity in those at risk of mental health conditions to see if physical activity can prevent the development of mental disorders.

Overprescribed Medications for US Adults: Four Major Examples

To understand possible medication overprescribing, it would be important to know which classes are the most prescribed, for which indications, for what duration, and for which age groups. Among the 10 most frequently prescribed medication classes for US adults, four were evaluated for overprescribing, and systematically assessed in relation to their primary indication. The assessment included usage patterns, trends, age of recipients, treatment duration, and benefits versus adverse consequences. The findings in this selective review are supported by an extensive search of the medical literature. The four selected medication categories and their most common indication included opioids for chronic pain, proton pump inhibitors for indigestion, levothyroxine for subclinical hypothyroidism, and antidepressants for subsyndromal levels of depression. These medications, grouped by their most frequent indication along with polypharmacy, have experienced major prescription increases in recent years, particularly among older patients. Most concerning is that they have been frequently prescribed for extended periods, usually with inadequate evidence of benefit. High drug usage patterns can aid in quantifying overprescribing within polypharmacy by age group.