Psychiatry - Research Publications

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http://hdl.handle.net/11343/232

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The Study of Ketamine for Youth Depression (SKY-D): study protocol for a randomised controlled trial of low-dose ketamine for young people with major depressive disorder

Schwartz, OS ; Amminger, P ; Baune, BT ; Bedi, G ; Berk, M ; Cotton, SM ; Daglas-Georgiou, R ; Glozier, N ; Harrison, B ; Hermens, DF ; Jennings, E ; Lagopoulos, J ; Loo, C ; Mallawaarachchi, S ; Martin, D ; Phelan, B ; Read, N ; Rodgers, A ; Schmaal, L ; Somogyi, AA ; Thurston, L ; Weller, A ; Davey, CG (BMC, 2023-10-24)

BACKGROUND: Existing treatments for young people with severe depression have limited effectiveness. The aim of the Study of Ketamine for Youth Depression (SKY-D) trial is to determine whether a 4-week course of low-dose subcutaneous ketamine is an effective adjunct to treatment-as-usual in young people with major depressive disorder (MDD). METHODS: SKY-D is a double-masked, randomised controlled trial funded by the Australian Government's National Health and Medical Research Council (NHMRC). Participants aged between 16 and 25 years (inclusive) with moderate-to-severe MDD will be randomised to receive either low-dose ketamine (intervention) or midazolam (active control) via subcutaneous injection once per week for 4 weeks. The primary outcome is change in depressive symptoms on the Montgomery-Åsberg Depression Rating Scale (MADRS) after 4 weeks of treatment. Further follow-up assessment will occur at 8 and 26 weeks from treatment commencement to determine whether treatment effects are sustained and to investigate safety outcomes. DISCUSSION: Results from this trial will be important in determining whether low-dose subcutaneous ketamine is an effective treatment for young people with moderate-to-severe MDD. This will be the largest randomised trial to investigate the effects of ketamine to treat depression in young people. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry ID: ACTRN12619000683134. Registered on May 7, 2019. https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=377513 .
Predictors of suicidal ideation severity among treatment-seeking young people with major depressive disorder: The role of state and trait anxiety

Moller, C ; Badcock, PB ; Hetrick, SE ; Rice, S ; Berk, M ; Witt, K ; Chanen, AM ; Dean, OM ; Gao, C ; Cotton, SM ; Davey, CG (SAGE PUBLICATIONS LTD, 2023-08)

OBJECTIVE: Depression and suicidal ideation are closely intertwined. Yet, among young people with depression, the specific factors that contribute to changes in suicidal ideation over time are uncertain. Factors other than depressive symptom severity, such as comorbid psychopathology and personality traits, might be important contributors. Our aim was to identify contributors to fluctuations in suicidal ideation severity over a 12-week period in young people with major depressive disorder receiving cognitive behavioural therapy. METHODS: Data were drawn from two 12-week randomised, placebo-controlled treatment trials. Participants (N = 283) were 15-25 years old, with moderate to severe major depressive disorder. The primary outcome measure was the Suicidal Ideation Questionnaire, administered at baseline and weeks 4, 8 and 12. A series of linear mixed models was conducted to examine the relationship between Suicidal Ideation Questionnaire score and demographic characteristics, comorbid psychopathology, personality traits and alcohol use. RESULTS: Depression and anxiety symptom severity, and trait anxiety, independently predicted higher suicidal ideation, after adjusting for the effects of time, demographics, affective instability, non-suicidal self-injury and alcohol use. CONCLUSIONS: Both state and trait anxiety are important longitudinal correlates of suicidal ideation in depressed young people receiving cognitive behavioural therapy, independent of depression severity. Reducing acute psychological distress, through reducing depression and anxiety symptom severity, is important, but interventions aimed at treating trait anxiety could also potentially be an effective intervention approach for suicidal ideation in young people with depression.
Regional, circuit and network heterogeneity of brain abnormalities in psychiatric disorders

Segal, A ; Parkes, L ; Aquino, K ; Kia, SM ; Wolfers, T ; Franke, B ; Hoogman, M ; Beckmann, CF ; Westlye, LT ; Andreassen, OA ; Zalesky, A ; Harrison, BJ ; Davey, CG ; Soriano-Mas, C ; Cardoner, N ; Tiego, J ; Yucel, M ; Braganza, L ; Suo, C ; Berk, M ; Cotton, S ; Bellgrove, MA ; Marquand, AF ; Fornito, A (Nature Research, 2023-09)

The substantial individual heterogeneity that characterizes people with mental illness is often ignored by classical case-control research, which relies on group mean comparisons. Here we present a comprehensive, multiscale characterization of the heterogeneity of gray matter volume (GMV) differences in 1,294 cases diagnosed with one of six conditions (attention-deficit/hyperactivity disorder, autism spectrum disorder, bipolar disorder, depression, obsessive-compulsive disorder and schizophrenia) and 1,465 matched controls. Normative models indicated that person-specific deviations from population expectations for regional GMV were highly heterogeneous, affecting the same area in <7% of people with the same diagnosis. However, these deviations were embedded within common functional circuits and networks in up to 56% of cases. The salience-ventral attention system was implicated transdiagnostically, with other systems selectively involved in depression, bipolar disorder, schizophrenia and attention-deficit/hyperactivity disorder. Phenotypic differences between cases assigned the same diagnosis may thus arise from the heterogeneous localization of specific regional deviations, whereas phenotypic similarities may be attributable to the dysfunction of common functional circuits and networks.
A brain model of altered self-appraisal in social anxiety disorder.

Jamieson, AJ ; Harrison, BJ ; Delahoy, R ; Schmaal, L ; Felmingham, KL ; Phillips, L ; Davey, CG (Springer Science and Business Media LLC, 2023-11-11)

The brain's default mode network has a central role in the processing of information concerning oneself. Dysfunction in this self-referential processing represents a key component of multiple mental health conditions, particularly social anxiety disorder (SAD). This case-control study aimed to clarify alterations to network dynamics present during self-appraisal in SAD participants. A total of 38 adolescents and young adults with SAD and 72 healthy control participants underwent a self-referential processing fMRI task. The task involved two primary conditions of interest: direct self-appraisal (thinking about oneself) and reflected self-appraisal (thinking about how others might think about oneself). Dynamic causal modeling and parametric empirical Bayes were then used to explore differences in the effective connectivity of the default mode network between groups. We observed connectivity differences between SAD and healthy control participants in the reflected self-appraisal but not the direct self-appraisal condition. Specifically, SAD participants exhibited greater excitatory connectivity from the posterior cingulate cortex (PCC) to medial prefrontal cortex (MPFC) and greater inhibitory connectivity from the inferior parietal lobule (IPL) to MPFC. In contrast, SAD participants exhibited reduced intrinsic connectivity in the absence of task modulation. This was illustrated by reduced excitatory connectivity from the PCC to MPFC and reduced inhibitory connectivity from the IPL to MPFC. As such, participants with SAD showed changes to afferent connections to the MPFC which occurred during both reflected self-appraisal as well as intrinsically. The presence of connectivity differences in reflected and not direct self-appraisal is consistent with the characteristic fear of negative social evaluation that is experienced by people with SAD.
Functional connectivity signatures of major depressive disorder: machine learning analysis of two multicenter neuroimaging studies

Gallo, S ; El-Gazzar, A ; Zhutovsky, P ; Thomas, RM ; Javaheripour, N ; Li, M ; Bartova, L ; Bathula, D ; Dannlowski, U ; Davey, C ; Frodl, T ; Gotlib, I ; Grimm, S ; Grotegerd, D ; Hahn, T ; Hamilton, PJ ; Harrison, BJ ; Jansen, A ; Kircher, T ; Meyer, B ; Nenadic, I ; Olbrich, S ; Paul, E ; Pezawas, L ; Sacchet, MD ; Saemann, P ; Wagner, G ; Walter, H ; Walter, M ; van Wingen, G (SPRINGERNATURE, 2023-07)

The promise of machine learning has fueled the hope for developing diagnostic tools for psychiatry. Initial studies showed high accuracy for the identification of major depressive disorder (MDD) with resting-state connectivity, but progress has been hampered by the absence of large datasets. Here we used regular machine learning and advanced deep learning algorithms to differentiate patients with MDD from healthy controls and identify neurophysiological signatures of depression in two of the largest resting-state datasets for MDD. We obtained resting-state functional magnetic resonance imaging data from the REST-meta-MDD (N = 2338) and PsyMRI (N = 1039) consortia. Classification of functional connectivity matrices was done using support vector machines (SVM) and graph convolutional neural networks (GCN), and performance was evaluated using 5-fold cross-validation. Features were visualized using GCN-Explainer, an ablation study and univariate t-testing. The results showed a mean classification accuracy of 61% for MDD versus controls. Mean accuracy for classifying (non-)medicated subgroups was 62%. Sex classification accuracy was substantially better across datasets (73-81%). Visualization of the results showed that classifications were driven by stronger thalamic connections in both datasets, while nearly all other connections were weaker with small univariate effect sizes. These results suggest that whole brain resting-state connectivity is a reliable though poor biomarker for MDD, presumably due to disease heterogeneity as further supported by the higher accuracy for sex classification using the same methods. Deep learning revealed thalamic hyperconnectivity as a prominent neurophysiological signature of depression in both multicenter studies, which may guide the development of biomarkers in future studies.
Frontoamygdalar Effective Connectivity in Youth Depression and Treatment Response

Kung, P-H ; Davey, CG ; Harrison, BJ ; Jamieson, AJ ; Felmingham, KL ; Steward, T (ELSEVIER SCIENCE INC, 2023-12-15)

BACKGROUND: Emotion regulation deficits are characteristic of youth depression and are underpinned by altered frontoamygdalar function. However, the causal dynamics of frontoamygdalar pathways in depression and how these dynamics relate to treatment prognosis remain unexplored. This study aimed to assess frontoamygdalar effective connectivity during cognitive reappraisal in youths with depression and to test whether pathway dynamics are predictive of individual response to combined cognitive behavioral therapy plus treatment with fluoxetine or placebo. METHODS: One hundred seven young people with moderate to severe depression and 94 healthy control participants completed a functional magnetic resonance imaging cognitive reappraisal task. After the task, 87 participants with depression were randomized and received 12 weeks of cognitive behavioral therapy plus either fluoxetine or placebo. Dynamic causal modeling was used to map frontoamygdalar effective connectivity during reappraisal and to assess the predictive capacity of baseline frontoamygdalar effective connectivity on depression diagnosis and posttreatment depression remission. RESULTS: Young people with depression showed weaker inhibitory modulation of ventrolateral prefrontal cortex to amygdala connectivity during reappraisal (0.29 Hz, posterior probability = 1.00). Leave-one-out cross-validation demonstrated that this effect was sufficiently large to predict individual diagnostic status (r = 0.20, p = .003). Posttreatment depression remission was associated with weaker excitatory ventromedial prefrontal cortex to amygdala connectivity (-0.56 Hz, posterior probability = 1.00) during reappraisal at baseline, though this effect did not predict individual remission status (r = -0.02, p = .561). CONCLUSIONS: Frontoamygdalar effective connectivity shows promise in identifying youth depression diagnosis, and circuits responsible for negative affect regulation are implicated in responsiveness to first-line depression treatments.
Effectiveness of atypical antipsychotics for unipolar and bipolar depression in adolescents and young adults: A systematic review and meta-analysis

Garcia-Rodriguez, L ; Burton, DJ ; Leonards, CA ; Davey, CG (ELSEVIER, 2023-10-15)

BACKGROUND: Antipsychotic medications are increasingly used for difficult-to-treat depression in young people. However, the evidence-base for this is unclear. Our aim was to assess the evidence for the efficacy of atypical antipsychotics in treating unipolar and bipolar depression in adolescents and young adults. METHOD: We conducted a comprehensive systematic review and meta-analysis of randomized-control-trial studies (RCTs) of antipsychotic medications for 10- to 25-year-olds with unipolar and bipolar depression. The primary outcome of interest was change in depressive symptoms from baseline to trial endpoint. RESULTS: No studies were identified that evaluated the use of antipsychotics in the treatment of unipolar depression. However, we identified four studies, of quetiapine, lurasidone and olanzapine/fluoxetine combination, comprising a total of 866 randomized patients, that evaluated treatment of bipolar depression. All studies used the Children's Depression Rating Scale-Revised (CDRS-R). Our meta-analysis revealed the weighted mean difference (WMD) was -4.58 (95 % CI, -6.59 to -2.57) between antipsychotic and placebo-treated groups. Response and remission rates were also significantly in favor of antipsychotic treatment. LIMITATIONS: There were few studies, several did not address risk-of-bias domains and there was a lack of non-industry sponsored studies. CONCLUSION: There is an absence of evidence for the use of antipsychotic medications in treatment of youth unipolar depression, and no recommendations can be made. There is some evidence for the efficacy of antipsychotics, specifically lurasidone and olanzapine/fluoxetine combination, in the treatment of young people with bipolar depression. However, this evidence is limited and more studies investigating the use of these medications in young people are needed.
Cannabidiol for Treatment-Resistant Anxiety Disorders in Young People: An Open-Label Trial

Berger, M ; Li, E ; Rice, S ; Davey, CG ; Ratheesh, A ; Adams, S ; Jackson, H ; Hetrick, S ; Parker, A ; Spelman, T ; Kevin, R ; McGregor, IS ; McGorry, P ; Amminger, GP (PHYSICIANS POSTGRADUATE PRESS, 2022-08-03)

Background: Treatment resistance is a significant problem among young people experiencing moderate-to-severe anxiety, affecting nearly half of all patients. This study investigated the safety and efficacy of cannabidiol (CBD), a non-intoxicating component of Cannabis sativa, for anxiety disorders in young people who previously failed to respond to standard treatment. Methods: In this open-label trial, 31 young people aged 12-25 years with a DSM-5 anxiety disorder and no clinical improvement despite treatment with cognitive-behavioral therapy and/or antidepressant medication were enrolled between May 16, 2018, and June 28, 2019. All participants received add-on CBD for 12 weeks on a fixed-flexible schedule titrated up to 800 mg/d. The primary outcome was improvement in anxiety severity, measured with the Overall Anxiety Severity and Impairment Scale (OASIS), at week 12. Secondary outcomes included comorbid depressive symptoms, Clinical Global Impressions scale (CGI) score, and social and occupational functioning. Results: Mean (SD) OASIS scores decreased from 10.8 (3.8) at baseline to 6.3 (4.5) at week 12, corresponding to a -42.6% reduction (P < .0001). Depressive symptoms (P < .0001), CGI-Severity scale scores (P = .0008), and functioning (P = .04) improved significantly. Adverse events were reported in 25 (80.6%) of 31 participants and included fatigue, low mood, and hot flushes or cold chills. There were no serious and/or unexpected adverse events. Conclusions: These findings suggest that CBD can reduce anxiety severity and has an adequate safety profile in young people with treatment-resistant anxiety disorders. Randomized controlled trials are needed to confirm the efficacy and longer-term safety of this compound. Trial Registration: New Zealand Clinical Trials Registry (ANZCTR) identifier: ACTRN12617000825358.
Cortico-Striatal Activity Characterizes Human Safety Learning via Pavlovian Conditioned Inhibition

Laing, PAF ; Steward, T ; Davey, CG ; Felmingham, KL ; Fullana, MA ; Vervliet, B ; Greaves, MD ; Moffat, B ; Glarin, RK ; Harrison, BJ (SOC NEUROSCIENCE, 2022-06-22)

Safety learning generates associative links between neutral stimuli and the absence of threat, promoting the inhibition of fear and security-seeking behaviors. Precisely how safety learning is mediated at the level of underlying brain systems, particularly in humans, remains unclear. Here, we integrated a novel Pavlovian conditioned inhibition task with ultra-high field (7 Tesla) fMRI to examine the neural basis of safety learning in 49 healthy participants. In our task, participants were conditioned to two safety signals: a conditioned inhibitor that predicted threat omission when paired with a known threat signal (A+/AX-), and a standard safety signal that generally predicted threat omission (BC-). Both safety signals evoked equivalent autonomic and subjective learning responses but diverged strongly in terms of underlying brain activation (PFDR whole-brain corrected). The conditioned inhibitor was characterized by more prominent activation of the dorsal striatum, anterior insular, and dorsolateral PFC compared with the standard safety signal, whereas the latter evoked greater activation of the ventromedial PFC, posterior cingulate, and hippocampus, among other regions. Further analyses of the conditioned inhibitor indicated that its initial learning was characterized by consistent engagement of dorsal striatal, midbrain, thalamic, premotor, and prefrontal subregions. These findings suggest that safety learning via conditioned inhibition involves a distributed cortico-striatal circuitry, separable from broader cortical regions involved with processing standard safety signals (e.g., CS-). This cortico-striatal system could represent a novel neural substrate of safety learning, underlying the initial generation of "stimulus-safety" associations, distinct from wider cortical correlates of safety processing, which facilitate the behavioral outcomes of learning.SIGNIFICANCE STATEMENT Identifying safety is critical for maintaining adaptive levels of anxiety, but the neural mechanisms of human safety learning remain unclear. Using 7 Tesla fMRI, we compared learning-related brain activity for a conditioned inhibitor, which actively predicted threat omission, and a standard safety signal (CS-), which was passively unpaired with threat. The inhibitor engaged an extended circuitry primarily featuring the dorsal striatum, along with thalamic, midbrain, and premotor/PFC regions. The CS- exclusively involved cortical safety-related regions observed in basic safety conditioning, such as the vmPFC. These findings extend current models to include learning-specific mechanisms for encoding stimulus-safety associations, which might be distinguished from expression-related cortical mechanisms. These insights may suggest novel avenues for targeting dysfunctional safety learning in psychopathology.
Assessing Suicidal Ideation in Young People With Depression: Factor Structure of the Suicidal Ideation Questionnaire

Moller, C ; Badcock, PB ; Hetrick, SE ; Rice, S ; Berk, M ; Dean, OM ; Chanen, AM ; Gao, C ; Davey, CG ; Cotton, SM (SAGE PUBLICATIONS INC, 2022-09-06)

Evaluating suicidal ideation in young people seeking mental health treatment is an important component of clinical assessment and treatment planning. To reduce the burden of youth suicide, we need to improve our understanding of suicidal ideation, its underlying constructs, and how ideation translates into suicidal behaviour. Using exploratory factor analysis, we investigated the dimensionality of the Suicidal Ideation Questionnaire (SIQ) among 273 participants aged 15-25 with Major Depressive Disorder. Area under the receiver operating characteristic curve (AUROC) analysis was used to explore associations between latent factors and actual suicidal behaviour. Findings suggested that the SIQ assesses multiple factors underlying suicidal ideation. AUROC analyses demonstrated that latent factors relating to both active and passive suicidal ideation predicted past-month suicidal behaviour and suicide attempt. These findings contribute to an improved understanding of the complexities of suicidal ideation and relationships with suicidal behaviour in young people with depression.

Psychiatry - Research Publications

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