Exclusion criteria and generalizability in bipolar disorder treatment trials

Druggable genome-wide Mendelian randomization for identifying the role of integrated stress response in therapeutic targets of bipolar disorder

For bipolar disorder (BD), the inconsistency of treatment guidelines and the long phases of pharmacological adjustment remain major challenges. BD is known to be comorbid with many medical and psychiatric conditions and they may share inflammatory and stress-related aetiologies, which could give rise to this association. The integrated stress response (ISR) responds to various stress conditions that lead to alterations in cellular homeostasis. However, as a causative mechanism underlying cognitive deficits and neurodegeneration in a broad range of brain disorders, the impact of ISR on BD is understudied. Mendelian randomization has been widely used to repurpose licensed drugs and discover novel therapeutic targets. Thus, we aimed to identify novel therapeutic targets for BD and analyze their pathophysiological mechanisms, using the summary data-based Mendelian Randomization (SMR) and Bayesian colocalization (COLOC) methods to integrate the summary-level data of the GWAS on BD and the expression quantitative trait locus (eQTL) study in blood. We utilized the GWAS data including 41,917 BD cases and 371,549 controls from the Psychiatric Genomics Consortium and the eQTL data from 31,684 participants of predominantly European ancestry from the eQTLGen consortium. The SMR analysis identified the EIF2B5 gene that was associated with BD due to no linkage but pleiotropy or causality. The COLOC analysis strongly suggested that EIF2B5 and the trait of BD were affected by shared causal variants, and thus were colocalized. Utilizing data in EpiGraphDB we find other putative causal BD genes (EIF2AK4 and GSK3B) to prioritize potential alternative drug targets.

Psilocybin-assisted psychotherapy for treatment resistant depression: A randomized clinical trial evaluating repeated doses of psilocybin

BACKGROUND

Psilocybin-assisted psychotherapy (PAP) has been associated with antidepressant effects. Trials to date have typically excluded participants with complex presentations. Our aim was to determine the feasibility of PAP in a complex population, including high levels of treatment resistance in major depressive and bipolar disorder and patients with baseline suicidality and significant comorbidity. We also evaluated flexible repeated doses over a 6-month period.

METHODS

Adults with treatment-resistant depression as part of major depressive or bipolar II disorder without psychosis or a substance use disorder were eligible to participate. Subjects were randomized to immediate treatment or waitlist control, with all eventually receiving PAP. Participants had one, two, or three psilocybin sessions with a fixed dose of 25 mg. Each dose was accompanied by preparation and integration psychotherapy sessions. Acceptability, safety, tolerability, and efficacy were evaluated (this study was registered at ClinicalTrials.gov: NCT05029466).

FINDINGS

Participants were randomized to immediate treatment (n = 16) or delayed treatment (n = 14). 29/30 were retained to the week-2 primary endpoint. Adverse events were transient, with no serious adverse events. Greater reductions in depression severity as measured by the Montgomery-Åsberg Depression Rating Scale (MADRS) were observed in the immediate treatment arm compared to the waitlist period arm with a large hedge's g effect size of 1.07 (p < 0.01). Repeated doses were associated with further reductions in MADRS scores compared to baseline.

CONCLUSIONS

PAP was feasible in complex patients with preliminary antidepressant efficacy and adequate safety and tolerability. Repeated doses were associated with greater reductions in depression severity.

FUNDING

This work was funded by Brain and Cognition Discovery Foundation (BCDF), Usona, and Braxia Scientific.

A toolkit for capturing a representative and equitable sample in health research

Research participants often do not represent the general population. Systematic exclusion of particular groups from research limits the generalizability of research findings and perpetuates health inequalities. Groups considered underserved by research include those whose inclusion is lower than expected based on population estimates, those with a high healthcare burden but limited research participation opportunities and those whose healthcare engagement is less than others. The REP-EQUITY toolkit guides representative and equitable inclusion in research. The toolkit was developed through a methodological systematic review and synthesis and finalized in a consensus workshop with 24 participants. The REP-EQUITY toolkit describes seven steps for investigators to consider in facilitating representative and equitable sample selection. This includes clearly defining (1) the relevant underserved groups, (2) the aims relating to equity and representativeness, (3) the sample proportion of individuals with characteristics associated with being underserved by research, (4) the recruitment goals, (5) the strategies by which external factors will be managed, (6) the methods by which representation in the final sample will be evaluated and (7) the legacy of having used the toolkit. Using the REP-EQUITY toolkit could promote trust between communities and research institutions, increase diverse participation in research and improve the generalizability of health research. National Institute for Health and Care Research PROSPERO identifier: CRD42022355391.

A literature review of the impact of exclusion criteria on generalizability of clinical trial findings to patients with chronic pain

The ability of clinical trials to inform the care of chronic pain may be limited if only an unrepresentative subset of patients are allowed to enroll. We summarize and report new insights on published studies that report on how trial exclusions affect the generalizability of their results. We conducted a PubMed search on the following terms: (("eligibility criteria" AND generalizability) OR ("exclusion criteria" AND generalizability) OR "exclusion criteria"[ti] OR "eligibility criteria"[ti]) AND pain. We only considered studies relevant if they analyzed data on (1) the prevalence and nature of exclusion criteria or (2) the impact of exclusion criteria on sample representativeness or study results. The 4 articles that were identified reported differences in patients who were included and excluded in different clinical trials: excluded patients were older, less likely to have a paid job, had more functional limitations at baseline, and used strong opioids more often. The clinical significance of these differences remains unclear. The pain medicine literature has very few published studies on the prevalence and impact of exclusion criteria, and the outcomes of excluded patients are rarely tracked. The frequent use of psychosocial exclusions is especially compromising to generalizability because chronic pain commonly co-occurs with psychiatric comorbidities. Inclusion of more representative patients in research samples can reduce recruitment barriers and broaden the generalizability of findings in patients with chronic pain. We also call for more studies that examine the use of exclusion criteria in chronic pain trials to better understand their implications.

Practical Research Ethics in Psychiatric Clinical Trials: A Guide for Investigators

The conduct of clinical psychiatric research is critical to advance the science and efficacy of treatment while also safeguarding the interests of participants. This article emerges from the authors' experience, providing practical guidance to colleagues seeking input on how to design and implement clinical research protocols in accordance with key ethical considerations. Thus, the intent of this article is to provide (1) an overview of common ethical considerations when conducting psychiatric clinical research along with (2) practical advice for preparing Institutional Review Board applications and associated materials in the ethical conduct of psychiatric clinical research.

Antipsychotic Polypharmacy for the Management of Schizophrenia: Evidence and Recommendations

Schizophrenia is a debilitating illness with a lifetime prevalence estimate of 0.6% and consists of symptoms from the positive, negative, and cognitive domains. Social support, therapy, psychoeducation, and overall case management are very important aspects of the treatment of schizophrenia. However, as abnormalities in neurotransmission are one of the key findings of schizophrenia pathology, pharmacotherapies are cornerstones of the management of schizophrenia. Antipsychotics have been used as the primary pharmacological treatment of schizophrenia. These agents often have a good effect on reducing positive symptoms, but may not markedly improve negative symptoms or cognitive defects. However, at least 20% of individuals with schizophrenia do not experience a substantial response from monotherapy with antipsychotics. Further, despite evolving treatment protocols and advances in early recognition of the disorder, 70% of patients with schizophrenia require long-term, even lifetime, medication to control their symptoms and do not achieve complete recovery. To address these shortcomings, clinicians and research scientists have explored different combinations of treatments, polypharmacy, to improve the treatment of patients. Antipsychotic polypharmacy has been shown to cause more side effects than monotherapy, which is the main reason why most treatment guidelines caution against it. Antipsychotic monotherapy should be strived for and clozapine should be tried at the latest if two monotherapy trials with other antipsychotics have failed and no absolute contraindications exist. If residual symptoms exist despite trials of adequate dose and duration, other reasons that may reduce treatment effect should be ruled out. Long-acting injectables or blood concentration measurements should be considered to affirm compliance and proper serum levels. Antipsychotic polypharmacy should be considered and discussed with patients from whom the aforementioned procedures do not produce a satisfactory treatment result. In some cases, antipsychotic polypharmacy may produce better results than other forms of treatment augmentation, such as benzodiazepines. In particular, combining aripiprazole with clozapine may be effective in reducing treatment side effects or residual symptoms, and this is likely to hold true for combining other partial dopamine D₂ agonists with clozapine as well, although currently scant data exist. More research is needed, both in controlled but also real-world settings, to define optimal antipsychotic polypharmacy and/or other psychotropic treatment augmentation strategies for specific patient groups and situations.

The efficacy of repetitive transcranial magnetic stimulation (rTMS) for bipolar depression: A systematic review and meta-analysis

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) has established efficacy in the treatment of unipolar depression and a growing evidence base in the treatment of bipolar depression. The objective of this study was to provide an estimate of the efficacy of rTMS in bipolar depression as an up to date synthesis of this literature is lacking.

METHODS

We conducted a systematic review of the sham-controlled randomized controlled trial (RCT) literature examining rTMS in bipolar depression. Studies were included if they included participants with bipolar depression in both sham- and active arms. The primary outcome parameter was rate of clinical response, defined as a 50% reduction as compared to baseline, on an established depression rating scale. Quantitative synthesis was performed using the Maentel-Haenszel random-effects model.

RESULTS

Data from a total of 274 patients from 14 studies were retained in the quantitative synthesis. The response rates were higher in rTMS compared to sham treatment (odds ratio (OR) = 2.72. 95%CI: 1.44-5.14). When stimulation protocols were analysed separately, statistically significant clinical response was only observed for high-frequency rTMS over the left dorsolateral prefrontal cortex (OR = 2.57, 95%CI: 1.17-5.66).

LIMITATIONS

Most data was extracted from trials including very few participants with bipolar depression (predominantly unipolar depression samples). Large confirmatory RCTs of rTMS specifically for bipolar depression are lacking.

CONCLUSION

rTMS seems effective in the treatment of bipolar depression, but dedicated and adequately powered RCTs are needed in order to firmly conclude that rTMS should be offered routinely for the treatment of bipolar depression.

A Combined Digital and Biomarker Diagnostic Aid for Mood Disorders (the Delta Trial): Protocol for an Observational Study

Background

Mood disorders affect hundreds of millions of people worldwide, imposing a substantial medical and economic burden. Existing diagnostic methods for mood disorders often result in a delay until accurate diagnosis, exacerbating the challenges of these disorders. Advances in digital tools for psychiatry and understanding the biological basis of mood disorders offer the potential for novel diagnostic methods that facilitate early and accurate diagnosis of patients.

Objective

The Delta Trial was launched to develop an algorithm-based diagnostic aid combining symptom data and proteomic biomarkers to reduce the misdiagnosis of bipolar disorder (BD) as a major depressive disorder (MDD) and achieve more accurate and earlier MDD diagnosis.

Methods

Participants for this ethically approved trial were recruited through the internet, mainly through Facebook advertising. Participants were then screened for eligibility, consented to participate, and completed an adaptive digital questionnaire that was designed and created for the trial on a purpose-built digital platform. A subset of these participants was selected to provide dried blood spot (DBS) samples and undertake a World Health Organization World Mental Health Composite International Diagnostic Interview (CIDI). Inclusion and exclusion criteria were chosen to maximize the safety of a trial population that was both relevant to the trial objectives and generalizable. To provide statistical power and validation sets for the primary and secondary objectives, 840 participants were required to complete the digital questionnaire, submit DBS samples, and undertake a CIDI.

Results

The Delta Trial is now complete. More than 3200 participants completed the digital questionnaire, 924 of whom also submitted DBS samples and a CIDI, whereas a total of 1780 participants completed a 6-month follow-up questionnaire and 1542 completed a 12-month follow-up questionnaire. The analysis of the trial data is now underway.

Conclusions

If a diagnostic aid is able to improve the diagnosis of BD and MDD, it may enable earlier treatment for patients with mood disorders.

International Registered Report Identifier (IRRID)

DERR1-10.2196/18453

20-Year Trends in the Pharmacologic Treatment of Bipolar Disorder by Psychiatrists in Outpatient Care Settings

OBJECTIVE

Pharmacological options for treating bipolar disorder have increased over the past 20 years, with several second-generation antipsychotics receiving regulatory approval in the 1990s. The authors describe trends in use of pharmacological agents in the outpatient management of bipolar disorder.

METHODS

Using nationally representative data from the 1997-2016 National Ambulatory Medical Care Surveys, the authors examined trends in the use of mood stabilizers, first- and second-generation antipsychotics, and antidepressants among psychiatrist visits for which bipolar disorder was listed among the primary diagnoses. A logistic regression model was used to identify statistically significant trends, with covariates including age, gender, race/ethnicity, and primary insurance.

RESULTS

Antipsychotics were increasingly more commonly prescribed, increasing from 12.4% of outpatient visits for bipolar disorder in the 1997-2000 period to 51.4% in the 2013-2016 period (adjusted odds ratio=5.05, 95% CI=3.65-7.01). Use of mood stabilizers decreased from 62.3% of visits for bipolar disorder in the 1997-2000 period to 26.4% in the 2013-2016 period (adjusted odds ratio=0.18, 95% CI=0.13-0.27). Prescription of antidepressants occurred in 47.0% of visits for bipolar disorder in the 1997-2000 period and 57.5% in the 2013-2016 period. Prescription of an antidepressant without a mood stabilizer increased substantially, from 17.9% in the 1997-2000 period to 40.9% in the 2013-2016 period (adjusted odds ratio=2.88, 95% CI=2.06-4.03).

CONCLUSIONS

Substantial changes have occurred in the treatment of bipolar disorder over the past 20 years, with second-generation antipsychotics in large measure supplanting traditional mood stabilizers. Antidepressant prescriptions persisted despite a lack of evidence for their efficacy in bipolar disorder and concerns about increasing the risk of mania. Research is needed to compare the real-world effectiveness and tolerability of newer antipsychotics with those of traditional mood stabilizers.

Applying a Transdiagnostic Cognitive-Behavioral Treatment to Adolescents at High Risk for Serious Mental Illness: Rationale and Preliminary Findings

Given the chronic and deleterious course of serious mental illness (SMI; schizophrenia and bipolar disorder), significant efforts have been undertaken to improve prediction of SMI and provide treatment for adolescents in the early, putatively prodromal stage of these illnesses. While risk assessments and disorder-specific treatments for adolescents at risk for SMI have shown some efficacy, significant issues remain around disorder-specific treatments for these youth. There is substantial heterogeneity of psychopathology within adolescents at high risk for SMI that leads to many false-positives and varying diagnostic outcomes. As a result, initial treatment focusing on broad symptoms and skills has been proposed in place of disorder-specific treatments. We discuss the rationale for providing an already-developed and empirically supported transdiagnostic treatment for emotional disorders (termed the Unified Protocol) as a first-line staging of treatment for adolescents experiencing early SMI symptoms. Additionally, we outline the open trial we are piloting using this transdiagnostic treatment in adolescents between the ages of 13 - 17 who have begun experiencing distressing yet subsyndromal psychosis or bipolar mood symptoms. Preliminary findings suggest feasibility and acceptability as well as initial efficacy in improving psychiatric symptoms, quality of life, and difficulties regulating emotions. We also present case studies from our open trial. A unified, cognitive-behavioral treatment for early presentations of SMI has important clinical and public health benefits, including streamlining treatment and providing broad skills that are applicable to a wide range of psychopathology.

Four Faces of Fair Subject Selection

Although the principle of fair subject selection is a widely recognized requirement of ethical clinical research, it often yields conflicting imperatives, thus raising major ethical dilemmas regarding participant selection. In this paper, we diagnose the source of this problem, arguing that the principle of fair subject selection is best understood as a bundle of four distinct sub-principles, each with normative force and each yielding distinct imperatives: (1) fair inclusion; (2) fair burden sharing; (3) fair opportunity; and (4) fair distribution of third-party risks. We first map out these distinct sub-principles, and then identify the ways in which they yield conflicting imperatives for the design of inclusion and exclusion criteria, and the recruitment of participants. We then offer guidance for how decision makers should navigate these conflicting imperatives to ensure that participants are selected fairly.

Personalized Pharmacotherapy for Bipolar Disorder: How to Tailor Findings From Randomized Trials to Individual Patient-Level Outcomes

The quest for "personalized medicine" in psychiatry has focused mainly on pursuing potential biomarkers such as pharmacogenetic predictors of drug response. However, the collective randomized trial database across phases of bipolar disorder allows one to identify clinical characteristics that inform the likelihood of desired treatment outcomes. In turn, those characteristics, termed moderators and mediators of drug response, enable those who administer treatment to construct clinical profiles that can help them tailor pharmacotherapies to the features of a given patient rather than simply to an overall diagnosis. Bipolar disorder typically involves more heterogeneous than uniform clinical presentations, partly because of its highly prevalent psychiatric and medical comorbid conditions. Further clinical diversity arises from characteristics such as bipolar I versus II disorder subtype, rapid cycling, mixed versus pure affective episodes, psychosis, anxiety, chronicity, cognitive dysfunction, and suicidality, among other distinguishing features. By coupling such profiles with an awareness of the psychotropic breadth of spectrum held by particular medications, clinicians can devise strategic combination therapy regimens, capitalizing on synergies and using drugs that exert multiple relevant effects, addressing comorbid conditions, incorporating medications that could offset adverse effects of other agents, and avoiding or deprescribing medication options that lack known evidence to target symptoms within the clinical profile of a given patient.