Rapid and sustained antidepressant effects of intravenous ketamine in treatment-resistant major depressive disorder and suicidal ideation: a randomized clinical trial.

BACKGROUND: Major depressive disorder (MDD) is the most disabling and burdensome mental disorder, negatively affecting an individual's quality of life and daily functioning. the current study was conducted with the aim of investigating the clinical effects of intravenous ketamine on symptoms of MDD and suicidal ideation. METHODS: The current randomized clinical trial was carried out on 64 patients diagnosed with treatment-resistant major depressive disorder between April and August 2022. The participants were randomly assigned to two groups: the intervention group received a dose of 0.5 mg/kg of ketamine, while the control group received normal saline. The Montgomery-Asberg Depression Scale and Beck's Suicidal Ideation Scale were utilized to assess depression and suicidal ideation, respectively. RESULTS: One hour after the administration of ketamine treatment, there was a notable and significant improvement in both depression symptoms (35.16 ± 8.13 vs. 14.90 ± 10.09) and suicidal ideation (6.74 ± 6.67 vs. 0.42 ± 1.52). Moreover, there were statistically significant differences in depression scores between the two groups at one hour, four hours, one day, three days, one week, one month, and two months after the administration of ketamine (p-value < 0.001). However, ketamine recipients frequently experienced side effects such as increased heart rate, headache, dizziness, and dissociative syndrome symptoms. CONCLUSION: The observed rapid onset of action and sustained effect demonstrate the potential of ketamine to provide relief from depressive symptoms in a shorter timeframe compared to traditional treatment approaches. These findings contribute to the growing body of evidence supporting the use of ketamine as a valuable therapeutic option for patients with treatment-resistant depression. IRCT REGISTRATION: IRCT registration number: IRCT20210806052096N1; IRCT URL: https://www.irct.ir/trial/62243 ; Ethical code: IR.ZUMS.REC.1400.150; Registration date: 2022-04-09.

Adults with depressive symptoms have lower odds of dietary supplement use.

OBJECTIVE: In this study, we aim to evaluate dietary supplement and complementary and alternative medicine (CAM) use in individuals with depressive symptoms. Furthermore, we conducted a comparative analysis of the usage of these agents among individuals with depressive symptoms, differentiating between those who were using antidepressants and those who were not. Additionally, we compared individuals with depressive symptoms who were not using antidepressants with participants who did not have depressive symptoms as well as individuals with depressive symptoms who were using antidepressants with individuals without depressive symptoms. METHOD: The National Health and Nutrition Examination Survey 2007-2018 data was collected. Depressive symptoms were assessed using patient health questionnaire-9. Dietary supplement and antidepressants use was evaluated using Dietary Supplement Use and Prescription Medications Questionnaires. RESULTS: 31,445 participants, with 2870 (8.05%) having depressive symptoms were included. Participants with depressive symptoms had significantly lower odds of dietary supplement use compared with those without depressive symptoms (aOR = 0.827, 95% CI: 0.700,0.977, p = 0.026). Participants with depressive symptoms who were using antidepressants had significantly higher odds of dietary supplement (aOR = 1.290, 95% CI: 1.038,1.604, p = 0.022) compared with participants with depressive symptoms who were not using antidepressants. Furthermore, Participants with depressive symptoms who weren't using antidepressants had significantly lower odds of dietary supplement use (aOR = 0.762, 95% CI: 0.632,0.918, p = 0.005) compared with participants without depressive symptoms. In individuals with treated depressive symptoms compared to those without depressive symptoms, CAM use was significantly lower (aOR = 0.763, 95% CI = 0.598,0.973, p = 0.030). CONCLUSION: Individuals with depressive symptoms have lower odds of dietary supplement use. Further studies are needed to replicate these findings and examine the underlying mechanisms for this association.

Barriers to Esketamine Nasal Spray Treatment Among Adults With Treatment-Resistant Depression.

Background: Under a risk evaluation and mitigation strategy program, esketamine nasal spray CIII requires self administration at a certified treatment center. Our objective was to identify factors associated with esketamine initiation and continuation.Methods: A retrospective observational cohort study was conducted among US adults who met treatment-resistant depression (TRD) criteria. Cases (n = 966) initiated esketamine between October 11, 2019, and February 28, 2022, and were compared to controls (n = 39,219) with TRD but no esketamine use. Outcomes included initiation, induction (8 administrations within 45 days), and interruptions (30-day treatment gap). Comorbid psychiatric conditions were identified using International Classification of Diseases, Tenth Revision, Clinical Modification, codes.Results: Cases resided significantly closer to treatment centers (8.9 vs 20.3 miles). Compared to 0-9 miles, initiation rate decreased by 11.9%, 50.8%, 68.1%, 75.9%, and 92.8% for individuals residing 10-19, 20-29, 30-39, 40-49, and 50+ miles from a center. After adjustment, factors associated with increased likelihood of initiation were posttraumatic stress disorder, major depressive disorder with suicidal ideation, and male sex, while increasing distance, substance use disorder, Medicaid, Charlson Comorbidity Index (CCI), and older age were associated with lower likelihood. Factors associated with lower likelihood of completing induction were Medicaid, low socioeconomic status (SES), CCI, and Hispanic communities. Factors associated with increased likelihood of interruption were alcohol use disorder, distance, and minority communities, while generalized anxiety disorder and Medicaid were associated with lower likelihood.Conclusions: Travel distance, insurance, low SES, and minority communities are potential barriers to treatment. Alternative care models may be needed to ensure adequate access to care.J Clin Psychiatry 2024;85(2):23m15102.

Suspected duloxetine-induced restless legs syndrome phenotypic variant: a case report.

BACKGROUND: Restless arms syndrome (RAS) is the most common variant of restless legs syndrome (RLS), which is easy to be ignored in clinical practice due to the lack of specific diagnostic criteria. When effective therapeutic agents induced RAS and symptoms persisted after briefly observation, clinicians will face the challenge of weighing efficacy against side effects. CASE PRESENTATION: A 67-year-old woman was admitted to a geriatric psychiatric ward with depression. Upon admission, the escitalopram dose was reduced from 15 mg to 10 mg per day, and the duloxetine dose was increased from 60 mg to 80 mg per day. The next night before bedtime, she developed itching and creeping sensations deep inside bilateral shoulders and arms, with the urge to move, worsening at rest, and alleviation after hammering. The symptoms persisted when escitalopram was discontinued. A history of RLS was confirmed. Treatment with 40 mg of duloxetine and 0.125 mg of pramipexole significantly improved depression, and the paresthesia disappeared, with no recurrence occurring 6 months after discharge. DISCUSSION AND CONCLUSIONS: This case suggests that psychiatrists should pay attention to RLS variants when increasing doses of duloxetine. Long-term improvement can be achieved through dosage reduction combined with dopaminergic drugs instead of immediate discontinuation.

Elevated SCN11A concentrations associated with lower serum lipid levels in patients with major depressive disorder.

The pathogenesis of major depressive disorder (MDD) involves lipid metabolism. Our earlier research also revealed that MDD patients had much lower total cholesterol (TC) concentrations than healthy controls (HCs). However, it is still unclear why TC decreased in MDD. Here, based on the Ingenuity Knowledge Base's ingenuity pathway analysis, we found that sodium voltage-gated channel alpha subunit 11A (SCN11A) might serve as a link between low lipid levels and MDD. We analyzed the TC levels and used ELISA kits to measure the levels of SCN11A in the serum from 139 MDD patients, and 65 HCs to confirm this theory and explore the potential involvement of SCN11A in MDD. The findings revealed that TC levels were considerably lower and SCN11A levels were remarkably increased in MDD patients than those in HCs, while they were significantly reversed in drug-treatment MDD patients than in drug-naïve MDD patients. There was no significant difference in SCN11A levels among MDD patients who used single or multiple antidepressants, and selective serotonin reuptake inhibitors or other antidepressants. Pearson correlation analysis showed that the levels of TC and SCN11A were linked with the Hamilton Depression Rating Scales score. A substantial association was also found between TC and SCN11A. Moreover, a discriminative model made up of SCN11A was discovered, which produced an area under a curve of 0.9571 in the training set and 0.9357 in the testing set. Taken together, our findings indicated that SCN11A may serve as a link between low lipid levels and MDD, and showed promise as a candidate biomarker for MDD.

A Review of Transcranial Magnetic Stimulation and Transcranial Direct Current Stimulation Combined with Medication and Psychotherapy for Depression.

LEARNING OBJECTIVES: After participating in this CME activity, the psychiatrist should be better able to:• Compare and contrast therapies used in combination with transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS) for treating MDD. BACKGROUND: Noninvasive neuromodulation, such as transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), has emerged as a major area for treating major depressive disorder (MDD). This review has two primary aims: (1) to review the current literature on combining TMS and tDCS with other therapies, such as psychotherapy and psychopharmacological interventions, and (2) to discuss the efficacy, feasibility, limitations, and future directions of these combined treatments for MDD. METHOD: This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched three databases: PubMed, PsycInfo, and Cochrane Library. The last search date was December 5, 2023. RESULTS: The initial search revealed 2,519 records. After screening and full-text review, 58 studies (7 TMS plus psychotherapy, 32 TMS plus medication, 7 tDCS plus psychotherapy, 12 tDCS plus medication) were included. CONCLUSIONS: The current literature on tDCS and TMS paired with psychotherapy provides initial support for integrating mindfulness interventions with both TMS and tDCS. Adding TMS or tDCS to stable doses of ongoing medications can decrease MDD symptoms; however, benzodiazepines may interfere with TMS and tDCS response, and antipsychotics can interfere with TMS response. Pairing citalopram with TMS and sertraline with tDCS can lead to greater MDD symptom reduction compared to using these medications alone. Future studies need to enroll larger samples, include randomized controlled study designs, create more uniform protocols for combined treatment delivery, and explore mechanisms and predictors of change.

Deprescribing of antidepressants: development of indicators of high-risk and overprescribing using the RAND/UCLA Appropriateness Method.

BACKGROUND: Antidepressants are first-line medications for many psychiatric disorders. However, their widespread long-term use in some indications (e.g., mild depression and insomnia) is concerning. Particularly in older adults with comorbidities and polypharmacy, who are more susceptible to adverse drug reactions, the risks and benefits of treatment should be regularly reviewed. The aim of this consensus process was to identify explicit criteria of potentially inappropriate antidepressant use (indicators) in order to support primary care clinicians in identifying situations, where deprescribing of antidepressants should be considered. METHODS: We used the RAND/UCLA Appropriateness Method to identify the indicators of high-risk and overprescribing of antidepressants. We combined a structured literature review with a 3-round expert panel, with results discussed in moderated meetings in between rounds. Each of the 282 candidate indicators was scored on a 9-point Likert scale representing the necessity of a critical review of antidepressant continuation (1-3 = not necessary; 4-6 = uncertain; 7-9 = clearly necessary). Experts rated the indicators for the necessity of review, since decisions to deprescribe require considerations of patient risk/benefit balance and preferences. Indicators with a median necessity rating of ≥ 7 without disagreement after 3 rating rounds were accepted. RESULTS: The expert panel comprised 2 general practitioners, 2 clinical pharmacologists, 1 gerontopsychiatrist, 2 psychiatrists, and 3 internists/geriatricians (total N = 10). After 3 assessment rounds, there was consensus for 37 indicators of high-risk and 25 indicators of overprescribing, where critical reviews were felt to be necessary. High-risk prescribing indicators included settings posing risks of drug-drug, drug-disease, and drug-age interactions or the occurrence of adverse drug reactions. Indicators with the highest ratings included those suggesting the possibility of cardiovascular risks (QTc prolongation), delirium, gastrointestinal bleeding, and liver injury in specific patient subgroups with additional risk factors. Overprescribing indicators target patients with long treatment durations for depression, anxiety, and insomnia as well as high doses for pain and insomnia. CONCLUSIONS: Explicit indicators of antidepressant high-risk and overprescribing may be used directly by patients and health care providers, and integrated within clinical decision support tools, in order to improve the overall risk/benefit balance of this commonly prescribed class of prescription drugs.

Reviving Bistable Perception in Patients With Depression by Decreasing the Overestimation of Prior Precision.

Slower perceptual alternations, a notable perceptual effect observed in psychiatric disorders, can be alleviated by antidepressant therapies that affect serotonin levels in the brain. While these phenomena have been well documented, the underlying neurocognitive mechanisms remain to be elucidated. Our study bridges this gap by employing a computational cognitive approach within a Bayesian predictive coding framework to explore these mechanisms in depression. We fitted a prediction error (PE) model to behavioral data from a binocular rivalry task, uncovering that significantly higher initial prior precision and lower PE led to a slower switch rate in patients with depression. Furthermore, serotonin-targeting antidepressant treatments significantly decreased the prior precision and increased PE, both of which were predictive of improvements in the perceptual alternation rate of depression patients. These findings indicated that the substantially slower perception switch rate in patients with depression was caused by the greater reliance on top-down priors and that serotonin treatment's efficacy was in its recalibration of these priors and enhancement of PE. Our study not only elucidates the cognitive underpinnings of depression, but also suggests computational modeling as a potent tool for integrating cognitive science with clinical psychology, advancing our understanding and treatment of cognitive impairments in depression.

Irritable bowel syndrome: low dose antidepressant improves symptoms.

The studyFord AC, Wright-Hughes A, Alderson SL, et al. Amitriptyline at low-dose and titrated for irritable bowel syndrome as second-line treatment in primary care (ATLANTIS): a randomised, double-blind, placebo-controlled, phase 3 trial. Lancet 2023;402:1773-85.To read the full NIHR Alert, go to: https://evidence.nihr.ac.uk/alert/irritable-bowel-syndrome-low-dose-antidepressant-improves-symptoms/.

miRNAs in treatment-resistant depression: a systematic review.

BACKGROUND: Treatment-resistant depression (TRD) is a condition in a subset of depressed patients characterized by resistance to antidepressant medications. The global prevalence of TRD has been steadily increasing, yet significant advancements in its diagnosis and treatment remain elusive despite extensive research efforts. The precise underlying pathogenic mechanisms are still not fully understood. Epigenetic mechanisms play a vital role in a wide range of diseases. In recent years, investigators have increasingly focused on the regulatory roles of miRNAs in the onset and progression of TRD. miRNAs are a class of noncoding RNA molecules that regulate the translation and degradation of their target mRNAs via interaction, making the exploration of their functions in TRD essential for elucidating their pathogenic mechanisms. METHODS AND RESULTS: A systematic search was conducted in four databases, namely PubMed, Web of Science, Cochrane Library, and Embase, focusing on studies related to treatment-resistant depression and miRNAs. The search was performed using terms individually or in combination, such as "treatment-resistant depression," "medication-resistant depression," and "miRNAs." The selected articles were reviewed and collated, covering the time period from the inception of each database to the end of February 2024. We found that miRNAs play a crucial role in the pathophysiology of TRD through three main aspects: 1) involvement in miRNA-mediated inflammatory responses (including miR-155, miR-345-5p, miR-146a, and miR-146a-5p); 2) influence on 5-HT transport processes (including miR-674,miR-708, and miR-133a); and 3) regulation of synaptic plasticity (including has-miR-335-5p,has-miR- 1292-3p, let-7b, and let-7c). Investigating the differential expression and interactions of these miRNAs could contribute to a deeper understanding of the molecular mechanisms underlying TRD. CONCLUSIONS: miRNAs might play a pivotal role in the pathogenesis of TRD. Gaining a deeper understanding of the roles and interrelations of miRNAs in TRD will contribute to elucidating disease pathogenesis and potentially provide avenues for the development of novel diagnostic and therapeutic strategies.

What predicts response to sertraline for people with depression in primary care? a secondary data analysis of moderators in the PANDA trial.

PURPOSE: Antidepressants are a first-line treatment for depression, yet many patients do not respond. There is a need to understand which patients have greater treatment response but there is little research on patient characteristics that moderate the effectiveness of antidepressants. This study examined potential moderators of response to antidepressant treatment. METHODS: The PANDA trial investigated the clinical effectiveness of sertraline (n = 326) compared with placebo (n = 329) in primary care patients with depressive symptoms. We investigated 11 potential moderators of treatment effect (age, employment, suicidal ideation, marital status, financial difficulty, education, social support, family history of depression, life events, health and past antidepressant use). Using multiple linear regression, we investigated the appropriate interaction term for each of these potential moderators with treatment as allocated. RESULTS: Family history of depression was the only variable with weak evidence of effect modification (p-value for interaction = 0.048), such that those with no family history of depression may have greater benefit from antidepressant treatment. We found no evidence of effect modification (p-value for interactions≥0.29) by any of the other ten variables. CONCLUSION: Evidence for treatment moderators was extremely limited, supporting an approach of continuing discuss antidepressant treatment with all patients presenting with moderate to severe depressive symptoms.

Positive Effect of 6-Gingerol on Functional Plasticity of Microglia in a rat Model of LPS-induced Depression.

Neuroinflammation has emerged as a crucial factor in the development of depression. Despite the well-known anti-inflammatory properties of 6-gingerol, its potential impact on depression remains poorly understood. This study aimed to investigate the antidepressant effects of 6-gingerol by suppressing microglial activation. In vivo experiments were conducted to evaluate the effect of 6-gingerol on lipopolysaccharide (LPS)-induced behavioral changes and neuroinflammation in rat models. In vitro studies were performed to examine the neuroprotective properties of 6-gingerol against LPS-induced microglial activation. Furthermore, a co-culture system of microglia and neurons was established to assess the influence of 6-gingerol on the expression of synaptic-related proteins, namely synaptophysin (SYP) and postsynaptic density protein 95 (PSD95), which are influenced by microglial activation. In the in vivo experiments, administration of 6-gingerol effectively alleviated LPS-induced depressive behavior in rats. Moreover, it markedly suppressed the activation of rat prefrontal cortex (PFC) microglia induced by LPS and the activation of the NF-κB/NLRP3 inflammatory pathway, while also reducing the levels of inflammatory cytokines IL-1ß and IL-18. In the in vitro experiments, 6-gingerol mitigated nuclear translocation of NF-κB p65, NLRP3 activation, and maturation of IL-1ß and IL-18, all of which were induced by LPS. Furthermore, in the co-culture system of microglia and neurons, 6-gingerol effectively restored the decreased expression of SYP and PSD95. The findings of this study demonstrate the neuroprotective effects of 6-gingerol in the context of LPS-induced depression-like behavior. These effects are attributed to the inhibition of microglial hyperactivation through the suppression of the NF-κB/NLRP3 inflammatory pathway.

Jnk1 and downstream signalling hubs regulate anxiety-like behaviours in a zebrafish larvae phenotypic screen.

Current treatments for anxiety and depression show limited efficacy in many patients, indicating the need for further research into the underlying mechanisms. JNK1 has been shown to regulate anxiety- and depressive-like behaviours in mice, however the effectors downstream of JNK1 are not known. Here we compare the phosphoproteomes from wild-type and Jnk1-/- mouse brains and identify JNK1-regulated signalling hubs. We next employ a zebrafish (Danio rerio) larvae behavioural assay to identify an antidepressant- and anxiolytic-like (AA) phenotype based on 2759 measured stereotypic responses to clinically proven antidepressant and anxiolytic (AA) drugs. Employing machine learning, we classify an AA phenotype from extracted features measured during and after a startle battery in fish exposed to AA drugs. Using this classifier, we demonstrate that structurally independent JNK inhibitors replicate the AA phenotype with high accuracy, consistent with findings in mice. Furthermore, pharmacological targeting of JNK1-regulated signalling hubs identifies AKT, GSK-3, 14-3-3 ζ/ε and PKCε as downstream hubs that phenocopy clinically proven AA drugs. This study identifies AKT and related signalling molecules as mediators of JNK1-regulated antidepressant- and anxiolytic-like behaviours. Moreover, the assay shows promise for early phase screening of compounds with anti-stress-axis properties and for mode of action analysis.

The safety and efficacy of escitalopram and sertraline in post-stroke depression: a randomized controlled trial.

OBJECTIVES: This study aims to evaluate the safety and efficacy of escitalopram and sertraline in post-stroke depression (PSD) patients, to provide more reliable therapeutics for cardiovascular and psychiatric clinical practice. METHODS: We recruited 60 patients (aged 40-89 years old) with an ICD-10 diagnosis of PSD, who were then randomly assigned to two groups and treated with flexible doses of escitalopram (10 to 20 mg/day, n = 30) or sertraline (50 to 200 mg/day, n = 30) for consecutive 8 weeks, respectively. The 24-item Hamilton Depression Rating Scale (HAMD-24), the 14-item Hamilton Anxiety Rating Scale (HAMA-14), the Treatment Emergent Symptom Scale (TESS), the Montreal Cognitive Assessment Scale (MOCA), and the Activity of Daily Living scale (ADL) were used to assess patients before, during, and after treatment for depression, anxiety, adverse effects, cognitive function, and daily living activities. Repeated measures ANOVA, the Mann-Whitney U test, the chi-square test (χ2), or Fisher's exact test was employed to assess baseline demographics, response rate, adverse effects rate, and changes in other clinical variables. RESULTS: Significant reduction in HAMD-24 and HAMA-14 scores was evaluated at baseline, as well as 1, 3, 4, 6, and 8 weeks of drug intervention (p < 0.01). There was a significant group difference in post-treatment HAMD-24 scores (p < 0.05), but no difference was observed in HAMA-14 scores (p > 0.05). Further analysis showed a significant variance in the HAMD-24 scores between the two groups at the end of the first week (p < 0.01). The incidence of adverse effects in both patient groups was mild, but there was a statistically significant difference between the two groups (p < 0.05). The improvement in cognitive function and the recovery of daily living abilities were comparable between both groups (p > 0.05). CONCLUSION: Escitalopram and sertraline showed comparable efficacy for anxiety symptoms, cognitive function, and daily living abilities in PSD patients. In addition, escitalopram was more appropriate for alleviating depressive symptoms. To validate the conclusion, trials with a larger sample size are in demand in the future. The registration number is ChiCTR1800017373.

High-definition transcranial direct current stimulation (HD-tDCS) in major depressive disorder with anxious distress-a study protocol for a double-blinded randomized sham-controlled trial.

BACKGROUND: Comorbid anxiety disorders and anxious distress are highly prevalent among individuals with major depressive disorder (MDD). The presence of the DSM-5 anxious distress specifier (ADS) has been associated with worse treatment outcomes and chronic disease course. Few studies have evaluated the therapeutic effects of High-definition transcranial direct current stimulation (HD-tDCS) on depressive and anxiety symptoms among MDD patients with ADS. The current randomized controlled trial aims to assess the efficacy of HD-tDCS as an augmentation therapy with antidepressants compared to sham-control in subjects of MDD with ADS. METHODS: MDD patients with ADS will be recruited and randomly assigned to the active HD-tDCS or sham HD-tDCS group. In both groups, patients will receive the active or sham intervention in addition to their pre-existing antidepressant therapy, for 2 weeks with 5 sessions per week, each lasting 30 min. The primary outcome measures will be the change of depressive symptoms, clinical response, and the remission rate as measured with the 17-item Hamilton Depression Rating Scale (HDRS-17) before and after the intervention and at the 2nd and 6th week after the completed intervention. Secondary outcome measures include anxiety symptoms, cognitive symptoms, disability assessment, and adverse effects. DISCUSSION: The HD-tDCS applied in this trial may have treatment effects on MDD with ADS and have minimal side effects. TRIAL REGISTRATION: The trial protocol is registered with www.chictr.org.cn under protocol registration number ChiCTR2300071726. Registered 23 May 2023.

Antidepressant nonadherence and sexual dysfunction among young adult males: the cross-sectional YAMAN study.

PURPOSE: Selective serotonin reuptake inhibitors are associated with high rates of nonadherence and sexual dysfunction, yet the correlation between these findings in young adult men is poorly characterized. We aimed to evaluate if young adult men are less willing to adhere to antidepressant treatment due to intolerable side effects, such as sexual dysfunction. METHODS: Deidentified, compensated survey that assessed baseline demographics, PHQ-8 and GAD-7 scores, attitudes towards antidepressant medication side effects, and perceptions of antidepressant medications including selective serotonin reuptake inhibitors, bupropion, and mirtazapine. RESULTS: From 665 delivered surveys, 505 respondents completed their survey (response rate: 76%), of which 486 were included for final analysis. After seeing common side effect profiles, our sample's willingness to take sexual function-sparing agents, such as bupropion or mirtazapine, was significantly greater than selective serotonin reuptake inhibitors (p < 0.001), with no significant difference between bupropion and mirtazapine (p = 0.263). The negative influence of erectile dysfunction and anorgasmia scored significantly higher than other common antidepressant side effects like weight gain, nausea, and dry mouth (range: p < 0.001, p = 0.043). With the exception of insomnia, participants indicated that experiencing sexual dysfunction while taking an antidepressant medication would lead to nonadherence at a significantly higher frequency than any other side effect assessed (range: p < 0.001, p = 0.005). CONCLUSION: The risk of experiencing sexual side effects when taking antidepressants could lead young adult men to become nonadherent to these medications. Strategies to augment the effectiveness of antidepressants, such as shared decision-making and the use of sexual function-sparing agents, are critical.

Therapeutic doses of ketamine acutely attenuate the aversive effect of losses during decision-making.

The discovery of rapid-acting antidepressant, ketamine has opened a pathway to a new generation of treatments for depression, and inspired neuroscientific investigation based on a new perspective that non-adaptive changes in the intrinsic excitatory and inhibitory circuitry might underlie the pathophysiology of depression. Nevertheless, it still remains largely unknown how the hypothesized molecular and synaptic levels of changes in the circuitry might mediate behavioral and neuropsychological changes underlying depression, and how ketamine might restore adaptive behavior. Here, we used computational models to analyze behavioral changes induced by therapeutic doses of ketamine, while rhesus macaques were iteratively making decisions based on gains and losses of tokens. When administered intramuscularly or intranasally, ketamine reduced the aversiveness of undesirable outcomes such as losses of tokens without significantly affecting the evaluation of gains, behavioral perseveration, motivation, and other cognitive aspects of learning such as temporal credit assignment and time scales of choice and outcome memory. Ketamine's potentially antidepressant effect was separable from other side effects such as fixation errors, which unlike outcome evaluation, was readily countered with strong motivation to avoid errors. We discuss how the acute effect of ketamine to reduce the initial impact of negative events could potentially mediate longer-term antidepressant effects through mitigating the cumulative effect of those events produced by slowly decaying memory, and how the disruption-resistant affective memory might pose challenges in treating depression. Our study also invites future investigations on ketamine's antidepressant action over diverse mood states and with affective events exerting their impacts at diverse time scales.