Association between cognitive functioning, suicidal ideation and suicide attempts in major depressive disorder, bipolar disorder, schizophrenia and related disorders: A systematic review and meta-analysis.

INTRODUCTION: Treatable mental disorders, such as psychotic, major depressive disorder (MDD), and bipolar disorder (BD), contribute to a substantial portion of suicide risk, often accompanied by neurocognitive deficits. We report the association between cognitive function and suicidal ideation/suicide attempts (SI/SA) in individuals with schizoaffective disorder, BD, and MDD. METHODS: A systematic search was conducted on PubMed, Ovid and Scopus databases for primary studies published from inception to April 2024. Eligible articles that reported on the effect size of association between cognition and SI/SA were pooled using a random effects model. RESULTS: A total of 41 studies were included for analysis. There was a negative association between executive functioning and SI/SA in schizoaffective disorder (SA: Corr = -0·78, 95 % CI [-1·00, 0·98]; SI: Corr = -0·06, 95 % CI [-0·85, 0·82]) and MDD (SA: Corr = -0·227, 95 % CI [-0·419, -0·017]; SI: Corr = -0·14, 95 % CI [-0·33, 0·06]). Results were mixed for BD, with a significant positive association between SA and global executive functioning (Corr = 0·08, 95 % CI [0·01, 0·15]) and negative association with emotion inhibition. Mixed results were observed for processing speed, attention, and learning and memory, transdiagnostically. LIMITATIONS: There is heterogeneity across sample compositions and cognitive measures. We did not have detailed information on individuals with respect to demographics and comorbidities. CONCLUSIONS: We observed a transdiagnostic association between measures of cognitive functions and aspects of suicidality. The interplay of cognitive disturbances, particularly in reward-based functioning, may underlie suicidality in individuals with mental disorders. Disturbances in impulse control, planning, and working memory may contribute to self-injurious behavior and suicide.

Case management in primary healthcare for people with complex needs to improve integrated care: a large-scale implementation study protocol.

INTRODUCTION: Case management (CM) is among the most studied effective models of integrated care for people with complex needs. The goal of this study is to scale up and assess CM in primary healthcare for people with complex needs. METHODS AND ANALYSIS: The research questions are: (1) which mechanisms contribute to the successful scale-up of CM for people with complex needs in primary healthcare?; (2) how do contextual factors within primary healthcare organisations contribute to these mechanisms? and (3) what are the relationships between the actors, contextual factors, mechanisms and outcomes when scaling-up CM for people with complex needs in primary healthcare? We will conduct a mixed methods Canadian interprovincial project in Quebec, New-Brunswick and Nova Scotia. It will include a scale-up phase and an evaluation phase. At inception, a scale-up committee will be formed in each province to oversee the scale-up phase. We will assess scale-up using a realist evaluation guided by the RAMESES checklist to develop an initial programme theory on CM scale-up. Then we will test and refine the programme theory using a mixed-methods multiple case study with 10 cases, each case being the scalable unit of the intervention in a region. Each primary care clinic within the case will recruit 30 adult patients with complex needs who frequently use healthcare services. Qualitative data will be used to identify contexts, mechanisms and certain outcomes for developing context-mechanism-outcome configurations. Quantitative data will be used to describe patient characteristics and measure scale-up outcomes. ETHICS AND DISSEMINATION: Ethics approval was obtained. Engaging researchers, decision-makers, clinicians and patient partners on the study Steering Committee will foster knowledge mobilisation and impact. The dissemination plan will be developed with the Steering Committee with messages and dissemination methods targeted for each audience.

Relationship between anhedonia and psychosocial functioning in post-COVID-19 condition: a post-hoc analysis.

BACKGROUND: Post-COVID-19 condition (PCC), also known as "long COVID," is characterized by persistent symptoms, negatively affecting the well-being of individuals with PCC. Anhedonia (i.e. reduced capacity for pleasure) and compromised psychosocial functioning are notable symptoms in those with PCC. We aimed to provide insights to understand the effects of anhedonia and impaired psychosocial functioning of individuals with PCC. METHODS: This post-hoc analysis used data from an 8-week, double-blind, randomized, placebo-controlled trial which evaluated vortioxetine for cognitive deficits in individuals with PCC (Clinicaltrials.gov Identifier: NCT05047952). A total of 147 eligible participants were randomly assigned to receive vortioxetine or matching placebo over eight weeks of double-blind treatment. Our study investigated the relationship between anhedonia, assessed by the Snaith-Hamilton Pleasure Scale (SHAPS), and psychosocial functioning, measured with the Post-COVID Functional Status (PCFS) scale. The analysis was conducted using a generalized linear model, with adjustments for relevant covariates such as age, sex, education, suspected versus confirmed COVID diagnosis, MDD diagnosis, and alcohol consumption. RESULTS: Of the 147 participants, 143 participants had available baseline data for analysis. We observed that baseline PCFS score was statistically significantly positively correlated to baseline SHAPS score (ß = 0.070, p = 0.045, 95% CI). DISCUSSIONS: Our analysis revealed a significant relationship between measures of anhedonia and psychosocial functioning in adults with PCC. Strategies that aim to improve patient-reported outcomes with PCC need to prioritize the prevention and treatment of hedonic disturbances in patients experiencing PCC.

Understanding the preferences of young adults with type 2 diabetes mellitus with regard to diabetes self-management education: a qualitative study.

AIM: Young-onset type 2 diabetes (YOD) is associated with poorer clinical outcomes. To support the development of more effective diabetes self-management education (DSME) programmes, this study aimed to understand the preferences of young adults with YOD in relation to the modality, content and qualities of DSME. METHODS: Maximal variation sampling was employed to recruit participants of varied age, ethnicity and marital status. In-depth interviews using a semistructured questionnaire were conducted. Subsequently, thematic analysis with coding and conceptualisation of data was applied to identify the main themes regarding DSME. RESULTS: 21 young adult participants aged 22-39 years were interviewed from three polyclinics in Singapore. The most used modalities for DSME included education from healthcare providers, information and support from family and friends and information from internet sources. Participants were most interested in information regarding diet, age-specific diabetes-related conditions and medication effects. Additionally, participants valued DSME that was credible, accessible, individualised and empathetic. Conversely, absence of the above qualities and stigma hindered participants from receiving DSME. CONCLUSION: Our study explored the preferences of young adults with YOD with regard to DSME, identifying the most used modalities, preferred content and qualities that were valued by young adults. Our findings will help inform the development of DSME programmes that can better meet the needs and preferences of young adults with YOD.

Understanding the impact of COVID-19 on antibiotic use in Canadian primary care: a matched-cohort study using EMR data.

BACKGROUND: Inappropriate or overuse of antibiotic prescribing in primary care highlights an opportunity for antimicrobial stewardship (AMS) programs aimed at reducing unnecessary use of antimicrobials through education, policies and practice audits that optimize antibiotic prescribing. Evidence from the early part of the pandemic indicates a high rate of prescribing of antibiotics for patients with COVID-19. It is crucial to surveil antibiotic prescribing by primary care providers from the start of the pandemic and into its endemic stage to understand the effects of the pandemic and better target effective AMS programs. METHODS: This was a matched pair population-based cohort study that used electronic medical record (EMR) data from the Canadian Primary Care Sentinel Surveillance Network (CPCSSN). Participants included all patients that visited their primary care provider and met the inclusion criteria for COVID-19, respiratory tract infection (RTI), or non-respiratory or influenza-like-illness (negative). Four outcomes were evaluated (a) receipt of an antibiotic prescription; (b) receipt of a non-antibiotic prescription; (c) a subsequent primary care visit (for any reason); and (d) a subsequent primary care visit with a bacterial infection diagnosis. Conditional logistic regression was used to evaluate the association between COVID-19 and each of the four outcomes. Each model was adjusted for location (rural or urban), material and social deprivation, smoking status, alcohol use, obesity, pregnancy, HIV, cancer and number of chronic conditions. RESULTS: The odds of a COVID-19 patient receiving an antibiotic within 30 days of their visit is much lower than for patients visiting for RTI or for a non-respiratory or influenza-like-illnesses (AOR = 0.08, 95% CI[0.07, 0.09] compared to RTI, and AOR = 0.43, 95% CI[0.38, 0.48] compared to negatives). It was found that a patient visit for COVID-19 was much less likely to have a subsequent visit for a bacterial infection at all time points. CONCLUSIONS: Encouragingly, COVID-19 patients were much less likely to receive an antibiotic prescription than patients with an RTI. However, this highlights an opportunity to leverage the education and attitude change brought about by the public health messaging during the COVID-19 pandemic (that antibiotics cannot treat a viral infection), to reduce the prescribing of antibiotics for other viral RTIs and improve antibiotic stewardship.

Impact of vortioxetine on depressive symptoms moderated by symptoms of anxiety in persons with post-COVID-19 condition: A secondary analysis.

OBJECTIVE: Recovery from a COVID-19 infection can lead to post-COVID-19 condition (PCC), which causes a multitude of debilitating symptoms that negatively affect an individual's health-related quality of life, including depressive and anxiety symptoms. We aim to examine the mediatory effects of anxiety on depressive symptoms in persons with PCC receiving vortioxetine. METHODS: We performed a post-hoc analysis of a randomized, double-blinded, placebo-controlled clinical trial investigating vortioxetine treatment on cognitive functioning in persons with PCC. Anxiety and depressive symptoms were measured by the 7-Item Generalized Anxiety Disorder (GAD-7) Scale and the 16-Item Quick Inventory of Depressive Symptomatology (QIDS-SR-16), respectively. RESULTS: Based on data of 147 participants, GAD-7 scores were significantly positively associated with QIDS-SR-16 scores (ß=0.038, 95 % CI [0.029,0.047], p < 0.001). After adjusting for covariates, a significant group (χ2=176.786, p < 0.001), time (χ2=8.914, p = 0.003), and treatment x time x GAD-7 score interaction (χ2=236.483, p < 0.001) effect was observed. Vortioxetine-treated participants had a significant difference in overall change in depressive symptoms (mean difference=-3.15, SEM=0.642, 95 % CI [-4.40,-1.89], p < 0.001). CONCLUSION: Anxiety symptoms were significantly associated with depressive symptoms in persons with PCC. Antidepressant efficacy on ameliorating depressive symptoms is dependent on improving anxiety symptoms, underscoring significant implications in improving treatment efficacy and patient quality of life.

Preclinical and clinical efficacy of kappa opioid receptor antagonists for depression: A systematic review.

BACKGROUND: Approximately 30 % of persons with Major Depressive Disorder (MDD) inadequately respond to conventional antidepressants. Kappa opioid receptor (KOR) antagonists, aticaprant and navacaprant, are in development as treatments for MDD. Herein, we aim to comprehensively evaluate the safety, efficacy and pharmacology of aticaprant and navacaprant for MDD. METHODS: We performed a systematic review of primary research investigating aticaprant and navacaprant on PubMed, OVID, and Scopus databases from inception to April 2024. Studies that reported on the pharmacological profile and/or safety and efficacy of aticaprant and navacaprant were included. RESULTS: Navacaprant monotherapy and aticaprant adjunctive therapy are in development for MDD. Navacaprant exhibits 300-fold selectivity for the KOR compared to the mu-opioid receptor, while aticaprant exhibits 30-fold selectivity. At clinically-relevant doses, navacaprant and aticaprant occupy 87-95 % and 73-94 % of KORs, respectively. Clinical trials of the foregoing agents (navacaprant as monotherapy and actiprant as adjunctive therapy) reported significant improvement in depressive symptoms and may clinically benefit measures of anhedonia. Both agents appear well-tolerated, with most adverse events mild and no known safety concerns. LIMITATIONS: Aticaprant and navacaprant treatment for MDD are in early stages of clinical trials and results from Phase 3 pivotal trials are not yet available. CONCLUSIONS: Kappa opioid receptor antagonists may serve as mechanistically-novel treatments for MDD and persons who inadequately respond to index conventional antidepressants. Anhedonia is debilitating and insufficiently treated with conventional antidepressants. Future research vistas should establish the efficacy and safety of KORAs in phase 3 studies in both acute and maintenance paradigms.

A replication study using the World Health Organization pharmacovigilance database (VigiBase®) to evaluate whether an association between ketamine and esketamine and alcohol and substance misuse exists.

BACKGROUND AND OBJECTIVES: Ketamine and esketamine are increasingly prescribed in the treatment of resistant mood disorders and persons at risk of suicide. Ketamine is a drug of misuse with increasing non-therapeutic use in the general population. Herein, our aim was to determine whether ketamine and/or esketamine are disproportionately associated with reports of substance and/or alcohol misuse. METHODS: Replicating a similar analysis recently conducted using the Food and Drug Administration Adverse Event Reporting System (FAERS) database, we identified cases of "alcohol problem, alcoholism, alcohol abuse, substance dependence, substance use disorder (SUD), substance abuse, drug dependence, drug use disorder and drug abuse" in association with ketamine and esketamine reported to the World Health Organization Pharmacovigilance Database (WHO VigiBase). We searched the database from inception to January 2024. The reporting odds ratio (ROR) of each of the aforementioned parameters was calculated; acetaminophen was used as the control. The numerator of the equation represents the number of cases (n) and the denominator represents the total cases of psychiatric disorders (N). Significance was obtained when the lower limit of the 95 % confidence (CI) > 1.0. RESULTS: The RORs for ketamine was increased for most parameters (i.e., alcohol abuse (3.24), substance dependence (12.48), substance use disorder (170.44), substance abuse (2.94), drug dependence (2.88), drug use disorder (11.54) and drug abuse (2.85), respectively). With respect to esketamine, the RORs were observed to be different from ketamine insofar as we observed a reduction in the RORs for three parameters (i.e., substance abuse (0.41), drug dependence (0.083) and drug abuse (0.052), respectively). The IC025 values were significant for ketamine in cases of alcohol abuse (0.35), substance dependence (0.50), substance use disorder (2.77), substance abuse (0.83), drug dependence (0.97), drug use disorder (1.95) and drug abuse (0.94). Additionally, oxycontin showed significant IC025 values for substance use disorder (0.0014), substance abuse (0.042), and drug dependence (0.17). CONCLUSION: Esketamine was not associated with an increased ROR for any parameter of alcohol and/or substance use disorder. Mixed results were observed with ketamine with some RORs increased and others decreased. Estimating RORs using a pharmacovigilance database does not establish causation in the case of elevated RORs and cannot be assumed to be a therapeutic effect when lower RORs were observed.

Interpretive Description in Computerized Ontology Development: Rigour.

This poster presents the use of Interpretive Description in ontology development. The methods selected attended to the need for quality and rigour.

Glucagon-like peptide 1 agonist and effects on reward behaviour: A systematic review.

INTRODUCTION: The roles of metabolic signals, including Glucagon-like peptide 1 (GLP-1), have been implicated in multiple domains outside metabolic regulation. There is a growing interest in repurposing Glucagon-like peptide 1 receptor agonists (GLP-1RAs) as therapeutics for motivation and reward-related behavioural disturbances. Herein, we aim to systematically review the extant evidence on the potential effects of GLP-1RAs on the reward system. METHODS: The study followed PRISMA guidelines using databases such as OVID, PubMed, Scopus, and Google Scholar. The search focused on "Reward Behavior" and "Glucagon Like Peptide 1 Receptor Agonists" and was restricted to human studies. Quality assessment achieved by the NIH's Quality Assessment of Controlled Intervention Studies RESULTS: GLP-1RAs consistently reduced energy intake and influenced reward-related behaviour. These agents have been associated with decreased neurocortical activation in response to higher rewards and food cues, particularly high-calorie foods, and lowered caloric intake and hunger levels. DISCUSSION: GLP-1RAs show promise in addressing reward dysfunction linked to food stimuli, obesity, and T2DM. They normalize insulin resistance, and might also modulate dopaminergic signalling and reduce anhedonia. Their effects on glycemic variability and cravings suggest potential applications in addiction disorders.

Comparing suicide completion rates in bipolar I versus bipolar II disorder: A systematic review and meta-analysis.

BACKGROUND: Bipolar disorder (BD) has a high disease burden and the highest mortality risk in BD comes from suicide. Bipolar disorder type II (BD-II) has been described as a milder form of bipolar disorder; however, extant literature is inconsistent with this description and instead describe illness burden and notably suicidality comparable to persons with bipolar I disorder (BD-I). Towards quantifying the hazard of BD-II, herein we aim via systematic review and meta-analysis to evaluate the rates of completed suicide in BD-I and BD-II. METHOD: We conducted a literature search on PubMed, OVID (Embase, Medline) and PsychINFO databases from inception to June 30th, 2023, according to PRISMA guidelines. Articles were selected based on the predetermined eligibility criteria. A meta-analysis was performed, comparing the risk of completed suicide between individuals diagnosed with BD-I to BD-II. RESULTS: Four out of eight studies reported higher suicide completion rates in persons living with BD-II when compared to persons living with BD-I; however, two of the studies reported non-significance. Two studies reported significantly higher suicide completion rates for BD-I than BD-II. The pooled odds ratio of BD-II suicide rates to BD-I was 1.00 [95 % CI = 0.75, 1.34]. LIMITATIONS: The overarching limitation is the small number of studies and heterogeneity of studies that report on suicide completion in BD-I and BD-II. CONCLUSION: Our study underscores the severity of BD-II, with a risk for suicide not dissimilar from BD-I. The greater propensity to depression, comorbidity and rapid-cycling course reported in BD-II are contributing factors to the significant mortality hazard in BD-II.

Prevalence and risk factors of depression and anxiety in primary care.

Introduction: Anxiety and depressive disorders are highly prevalent mental health conditions worldwide. However, little is known about their specific prevalence in primary care settings. This study aimed to determine the prevalence of depression and anxiety in the primary care population and identify associated patient characteristics. Method: We conducted a cross-sectional study using stratified sampling by age with a self-administered questionnaire survey in Singapore's National Health-care Group Polyclinics from December 2021 to April 2022. A total score of Patient Health Questionnaire-9 (PHQ-9) ≥10 represents clinical depression, and a total score of Generalised Anxiety Disorder-7 (GAD-7) ≥10 indicates clinical anxiety. Multivariable logistic regression was used to identify the factors associated with depression and anxiety. Results: A total of 5694 patients were approached and 3505 consented to the study (response rate=61.6%). There was a higher prevalence of coexisting clinical depression and anxiety (DA) (prevalence=5.4%) compared to clinical depression only (3.3%) and clinical anxiety only (1.9%). The odds of having DA were higher among those aged 21-39 years (odds ratio [OR] 13.49; 95% confidence interval [CI] 5.41-33.64) and 40-64 years (OR 2.28; 95% CI 1.03-5.03) compared to those ≥65 years. Women had higher odds of having DA (OR 2.33; 95% CI 1.54-3.50) compared to men. Respondents with diabetes had higher odds of having DA (OR 1.78; 95% CI 1.07-2.94) compared to those without diabetes. Conclusion: Coexisting clinical depression and anxiety are significantly present in the primary care setting, especially among younger individuals, patients with diabetes and women. Mental health screening programmes should include screening for both depression and anxiety, and target these at-risk groups.

Assessing the impact of Canadian primary care research and researchers: Citation analysis.

OBJECTIVE: To describe the citation impact and characteristics of Canadian primary care researchers and research publications. DESIGN: Citation analysis. SETTING: Canada. PARTICIPANTS: A total of 266 established Canadian primary care researchers. MAIN OUTCOME MEASURES: The 50 most cited primary care researchers in Canada were identified by analyzing data from the Scopus database. Various parameters, including the number of publications and citations, research themes, Scopus h index, content analysis, journal impact factors, and field-weighted citation impact for their publications, were assessed. Information about the characteristics of these researchers was collected using the Google search engine. RESULTS: On average, the 50 most cited primary care researchers produced 51.1 first-author publications (range 13 to 249) and were cited 1864.32 times (range 796 to 9081) over 29 years. Twenty-seven publications were cited more than 500 times. More than half of the researchers were men (60%). Most were clinician scientists (86%) with a primary academic appointment in family medicine (86%) and were affiliated with 5 universities (74%). Career duration was moderately associated with the number of first-author publications (0.35; P=.013). Most research focused on family practice, while some addressed health and health care issues (eg, continuing professional education, pharmaceutical policy). CONCLUSION: Canada is home to a cadre of primary care researchers who are highly cited in the medical literature, suggesting that their work is of high quality and relevance. Building on this foundation, further investments in primary care research could accelerate needed improvements in Canadian primary care policy and practice.

Association between dual orexin receptor antagonists (DORAs) and suicidality: reports to the United States Food and Drug Administration Adverse Event Reporting System (FAERS).

BACKGROUND: Package inserts for the FDA-approved dual orexin receptor antagonists (DORAs) suvorexant, lemborexant and daridorexant state that suicide risk should be monitored. It remains unknown whether suicidality is attributed to DORAs. We aim to evaluate suicidality associated with DORAs reported to the FDA Adverse Event Reporting System (FAERS). METHODS: The reporting odds ratio (ROR) was determined with trazodone as the control. Significant disproportionate reporting was determined when 95% confidence intervals (CIs) did not encompass 1.0. We used information components (ICs) to calculate the lower limit of the 95% CI (IC025). IC was significantly increased when the IC025 ≥0. RESULTS: Suvorexant (0.025 ROR), lemborexant (0.019 ROR) and daridorexant (0.002 ROR) were significantly associated with lower odds of reported completed suicides compared to trazodone (p < 0.05). There was no significantly increased RORs for the DORAs regarding suicidal ideation, depression suicidal, suicidal behavior and suicide attempts. Nonsignificant associations between all parameters of suicidality were observed for each DORA using IC025. CONCLUSION: We did not find a significant association between any parameter of suicidality captured in the FAERS for each DORA. All persons treated for insomnia pharmacologically/non-pharmacologically should be evaluated for emergence/worsening of any suicidality aspect.

The role of KCNQ channel activators in management of major depressive disorder.

Depression, a complex disorder with significant treatment challenges, necessitates innovative therapeutic approaches to address its multifaceted nature and enhance treatment outcomes. The modulation of KCNQ potassium (K+) channels, pivotal regulators of neuronal excitability and neurotransmitter release, is a promising innovative therapeutic target in psychiatry. Widely expressed across various tissues, including the nervous and cardiovascular systems, KCNQ channels play a crucial role in modulating membrane potential and regulating neuronal activity. Recent preclinical evidence suggests that KCNQ channels, particularly KCNQ3, contribute to the regulation of neuronal excitability within the reward circuitry, offering a potential target for alleviating depressive symptoms, notably anhedonia. Studies using animal models demonstrate that interventions targeting KCNQ channels can restore dopaminergic firing balance and mitigate depressive symptoms. Human studies investigating the effects of KCNQ channel activators, such as ezogabine, have shown promising results in alleviating depressive symptoms and anhedonia. The aforementioned observations underscore the therapeutic potential of KCNQ channel modulation in depression management and highlight the need and justification for phase 2 and phase 3 dose-finding studies as well as studies prespecifying symptomatic targets in depression including anhedonia.

Risk of VMAT2 inhibitors on suicidality and parkinsonism: report utilizing the United States Food and Drug Administration adverse event reporting system.

Prescription of vesicular monoamine transporter 2 (VMAT2) inhibitors, valbenazine, deutetrabenazine, and tetrabenazine, is becoming increasingly common in persons treated with antipsychotics. Reported suicidality and parkinsonism are safety concerns with VMAT2 inhibitors. Herein, we aim to evaluate the aforementioned safety outcomes using the FDA Adverse Event Reporting System. Reporting odds ratios (RORs) and lower limits of 95% confidence intervals of information components (IC025) were calculated to quantify VMAT2 inhibitor-associated adverse events. Acetaminophen was the reference agent. Suicidal ideation was significantly associated with VMAT2 inhibitors, with RORs ranging from 2.38 to 10.67 and IC025 ranging from 0.73 to 2.39. Increased odds of suicidal behavior was observed with tetrabenazine (ROR 3.011, IC025 0.0087), but not deutetrabenazine or valbenazine. Decreased odds of suicide attempts and completed suicide were observed with VMAT2 inhibitors, with RORs ranging from 0.011 to 0.10 (all IC025 < 0). Increased odds of parkinsonism were reported for all VMAT2 inhibitors, with RORs and IC025 ranging from 19.49 to 25.37 and 1.66 to 2.93, respectively. The mixed results with VMAT2 inhibitor-associated suicidality and parkinsonism do not establish causal relationships. The parameters of suicidality may be explained by underlying psychiatric disorders.

Spectral signatures of psilocybin, lysergic acid diethylamide (LSD) and ketamine in healthy volunteers and persons with major depressive disorder and treatment-resistant depression: A systematic review.

BACKGROUND: Electrophysiologic measures provide an opportunity to inform mechanistic models and possibly biomarker prediction of response. Serotonergic psychedelics (SPs) (i.e., psilocybin, lysergic acid diethylamide (LSD)) and ketamine represent new investigational and established treatments in mood disorders respectively. There is a need to better characterize the mechanism of action of these agents. METHODS: We conducted a systematic review investigating the spectral signatures of psilocybin, LSD, and ketamine in persons with major depressive disorder (MDD), treatment-resistant depression (TRD), and healthy controls. RESULTS: Ketamine and SPs are associated with increased theta power in persons with depression. Ketamine and SPs are also associated with decreased spectral power in the alpha, beta and delta bands in healthy controls and persons with depression. When administered with SPs, theta power was increased in persons with MDD when administered with SPs. Ketamine is associated with increased gamma band power in both healthy controls and persons with MDD. LIMITATIONS: The studies included in our review were heterogeneous in their patient population, exposure, dosing of treatment and devices used to evaluate EEG and MEG signatures. Our results were extracted entirely from persons who were either healthy volunteers or persons with MDD or TRD. CONCLUSIONS: Extant literature evaluating EEG and MEG spectral signatures indicate that ketamine and SPs have reproducible effects in keeping with disease models of network connectivity. Future research vistas should evaluate whether observed spectral signatures can guide further discovery of therapeutics within the psychedelic and dissociative classes of agents, and its prediction capability in persons treated for depression.

Effects of anhedonia on health-related quality of life and functional outcomes in major depressive disorder: A systematic review and meta-analysis.

BACKGROUND: Major depressive disorder (MDD) is a heterogeneous group of mood disorders. A prominent symptom domain is anhedonia narrowly defined as a loss of interest and ability to experience pleasure. Anhedonia is associated with depressive symptom severity, MDD prognosis, and suicidality. We perform a systematic review and meta-analysis of extant literature investigating the effects of anhedonia on health-related quality of life (HRQoL) and functional outcomes in persons with MDD. METHODS: A literature search was conducted on PubMed, OVID databases, and SCOPUS for published articles from inception to November 2023, reporting on anhedonia and patient-reported outcomes in persons with MDD. The reported correlation coefficients between anhedonia and self-reported measures of both HRQoL and functional outcomes were pooled using a random effects model. RESULTS: We identified 20 studies that investigated anhedonia with HRQoL and/or functional outcomes in MDD. Anhedonia as measured by the Snaith-Hamilton Pleasure Scale (SHAPS) scores had a statistically significant correlation with patient-reported HRQoL (r = -0.41 [95 % CI = -0.60, -0.18]) and functional impairment (r = 0.39 [95 % CI = 0.22, 0.54]). LIMITATIONS: These preliminary results primarily investigate correlations with consummatory anhedonia and do not distinguish differences in anticipatory anhedonia, reward valuation or reward learning; therefore, these results require replication. CONCLUSIONS: Persons with MDD experiencing symptoms of anhedonia are more likely to have worse prognosis including physical, psychological, and social functioning deficits. Anhedonia serves as an important predictor and target for future therapeutic and preventative tools in persons with MDD.

Number needed to treat (NNT) for ketamine and esketamine in adults with treatment-resistant depression: A systematic review and meta-analysis.

BACKGROUND: Ketamine has been established as efficacious in adults living with Treatment-resistant Depression (TRD). Toward providing a quantifiable estimate of the clinical meaningfulness of the therapeutic benefit of ketamine, herein, we conduct a systematic review that aims to report the Number Needed to Treat (NNT) and the Number Needed to Harm (NNH). METHODS: This systematic review searched Embase, Medline/Pubmed, PsycINFO and ClinicalTrials.gov from inception up to October 15th 2023, for placebo-controlled, Randomized Controlled Trials (RCTs) assessing racemic ketamine or esketamine therapy for unipolar TRD. We calculated NNT and NNH for ketamine treatments over various time points. RESULTS: A total of 21 studies with 2042 participants were included. Racemic ketamine treatments had pooled NNTs for response of 7 at 4 h, 3 from one day to one week and 9 for studies at four weeks. Esketamine treatment was found to have a similar efficacy with an NNT of 2 at one day and 11 at four weeks. NNH values indicated low risk for ketamine treatments. LIMITATIONS: Limitations in the data used include the possibility of functional unblinding and selective reporting bias. Moreover, the meta-analysis may have been limited in its precision by including low threshold definitions of treatment resistance (≥ 1 failed antidepressant) and low-dose ketamine treatments. CONCLUSION: Herein, we determined that the NNT for ketamine treatment in adults living with TRD across different intervals of observation was <10. We conclude that the NNTs observed herein are highly clinically meaningful in this difficult to treat disorder.