Early symptom improvement and other clinical predictors of response to repetitive transcranial magnetic stimulation for depression

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) is a rapidly emerging treatment for depression, but outcome prediction is still a challenge. This study aimed to identify predictors of response to rTMS among baseline clinical factors and early symptomatic improvements.

METHODS

This cohort study comprised 136 patients with a unipolar or bipolar depressive episode referred for clinical intermittent theta-burst stimulation or right-sided 1 Hz rTMS at the Uppsala Brain Stimulation Unit. The co-primary outcomes used for logistic regression were response, defined as ≥50 % reduction of Montgomery and Åsberg Depression Rating Scale Self-assessment (MADRS-S) total score, and 1-2 points on the Clinical Global Impression Improvement (CGI-I) scale. Early improvement was defined as ≥20 % reduction in the MADRS-S total score, or ≥ 1 point reduction in each MADRS-S item, after two weeks of treatment.

RESULTS

The response rates were 21 % for MADRS-S and 45 % for CGI-I. A depressive episode >24 months had lower odds for MADRS-S response compared to ≤12 months. Early improvement of the MADRS-S total score predicted CGI-I response (95 % CI = 1.35-9.47, p = 0.011), Initiative6 predicted MADRS-S response (95 % CI = 1.08-9.05, p = 0.035), and Emotional involvement7 predicted CGI-I response (95 % CI = 1.03-8.66, p = 0.044).

LIMITATIONS

No adjustment for concurrent medication.

CONCLUSIONS

A depressive episode ≤12 months and early improvement in overall depressive symptoms, as well as the individual items, Initiative6 and Emotional involvement7, predicted subsequent rTMS response in a naturalistic sample of depressed patients. This could facilitate the early identification of patients who will benefit from further rTMS sessions.

An exploratory study of the damage markers NfL, GFAP, and t-Tau, in cerebrospinal fluid and other findings from a patient cohort enriched for suspected autoimmune psychiatric disease

There is growing evidence suggesting that immunological mechanisms play a significant role in the development of psychiatric symptoms in certain patient subgroups. However, the relationship between clinical red flags for suspected autoimmune psychiatric disease and signs of central nervous system (CNS) pathology (e.g., routine cerebrospinal fluid (CSF) alterations, CNS damage markers, neurophysiological or neuroimaging findings) has received limited attention. Here, we aimed to describe the prevalence and distribution of potential CNS pathologies in psychiatric patients in relation to clinical red flags for autoimmune psychiatric disease and psychiatric symptoms. CSF routine findings and CNS damage markers; neurofilament light chain protein (NfL), glial fibrillary acidic protein (GFAP) and total Tau (t-Tau), in CSF from 127 patients with psychiatric disease preselected for suspected immunological involvement were related to recently proposed clinical red flags, psychiatric features, and MRI and EEG findings. Twenty-one percent had abnormal routine CSF findings and 27% had elevated levels of CNS damage markers. Six percent had anti-neuronal antibodies in serum and 2% had these antibodies in the CSF. Sixty-six percent of patients examined with MRI (n = 88) had alterations, mostly atrophy or nonspecific white matter lesions. Twenty-seven percent of patients with EEG recordings (n = 70) had abnormal findings. Elevated NfL levels were associated with comorbid autoimmunity and affective dysregulation symptoms. Elevated t-Tau was associated with catatonia and higher ratings of agitation/hyperactivity. Elevated GFAP was associated with acute onset, atypical presentation, infectious prodrome, tics, depressive/anxiety symptom ratings and overall greater psychiatric symptom burden. In conclusion, preselection based on suspected autoimmune psychiatric disease identifies a population with a high prevalence of CSF alterations suggesting CNS pathology. Future studies should examine the value of these markers in predicting treatment responses.

Electroconvulsive Therapy Versus Repetitive Transcranial Magnetic Stimulation in Patients With a Depressive Episode: A Register-Based Study

OBJECTIVES

Electroconvulsive therapy (ECT) and repetitive transcranial magnetic stimulation (rTMS) are both effective in treating depression. Although rTMS induces fewer adverse effects, its effectiveness relative to ECT is not well established. The aim of this study was to investigate the treatment outcomes of ECT and rTMS in patients who have received both interventions.

METHODS

This was a register-based observational crossover study in patients with depression who had undergone ECT and rTMS in Sweden between 2012 and 2021. Primary outcome was reduction in the Montgomery-Åsberg Depression Rating Scale-Self-report (MADRS-S) score. Secondary outcome was response defined as a 50% or greater decrease in the MADRS-S score. Subgroup analyses were performed to identify factors that predicted differential responses between rTMS and ECT. Continuous and categorical variables were analyzed using paired-samples t tests and McNemar tests, respectively.

RESULTS

In total, 138 patients across 19 hospitals were included. The MADRS-S score after ECT and rTMS was reduced by 15.0 and 5.6 ( P = 0.0001) points, respectively. Response rates to ECT and rTMS were 38% and 15% ( P = 0.0001), respectively. Electroconvulsive therapy was superior across all subgroups classified according to age and severity of depression.

CONCLUSIONS

Our results suggest that ECT is more effective than rTMS in treating depression among patients who have received both interventions. Age and baseline depression severity did not predict who would similarly benefit from rTMS and ECT.

The Swedish version of the Motivation and Pleasure Scale self-report (MAP-SR): psychometric properties in patients with schizophrenia or depression

PURPOSE

Negative symptoms are commonly regarded as a symptom dimension belonging to schizophrenia spectrum disorders but are also present in depression. The recently developed Clinical Assessment Interview for Negative Symptoms (CAINS) has shown to be reliable and valid. A corresponding self-report questionnaire has also been developed, named the Motivation and Pleasure Scale - Self Report (MAP-SR). The purpose was to evaluate the psychometric properties of the Swedish version of the MAP-SR in patients with either schizophrenia or depression.

MATERIALS AND METHODS

The MAP-SR was translated to Swedish. Participants were 33 patients with schizophrenia spectrum disorders and 52 patients with a depressive disorder and they completed the MAP-SR, the CAINS and other measures assessing adjacent psychopathology, functioning and cognition.

RESULTS

The internal consistency for the MAP-SR was adequate in both groups (schizophrenia spectrum α = .93, depressive disorder α = .82). Furthermore, the MAP-SR had a large correlation to the motivation and pleasure subscale of the CAINS in patients with schizophrenia disorders (r = -0.75, p < .001), however among patients with depression this correlation was medium-to-large (r = -0.48, p < 0.001).

CONCLUSIONS

Findings suggest that the Swedish version of the MAP-SR shows promise as a useful measure of motivation and pleasure, especially in patients with schizophrenia spectrum disorders. Furthermore, results also suggest that the MAP-SR does not assess negative symptoms specifically, but that there is an overlap between depressive and negative symptoms.

GABAA Receptor Availability in Relation to Cortical Excitability in Depressed and Healthy: A Positron Emission Tomography and Transcranial Magnetic Stimulation Study

INTRODUCTION

Gamma-aminobutyric acid (GABA) deficiency is suggested in depressive disorders, along with alterations in cortical excitability. However, whether these excitability changes are related to GABAA receptor availability is largely unknown. Our aim was to assess the correlation between these measures in depressed patients and healthy controls.

METHODS

Twenty-eight patients with a major depressive episode, measured before and after participating in a clinical trial with repetitive transcranial magnetic stimulation (TMS), and 15 controls underwent [11C]flumazenil positron emission tomography to assess GABAA receptor availability and paired pulse TMS (ppTMS) to evaluate cortical excitability. Both whole-brain voxel-wise GABAA receptor availability and mean values from left hand motor cortex and left paracentral lobule were correlated to the ppTMS outcomes: short-interval intracortical inhibition reflecting GABAA receptor activity, long-interval intracortical inhibition representing GABAB receptor activity, intracortical facilitation reflecting glutamate N-methyl-D-aspartate-receptor activity, as well as the resting motor threshold (rMT), considered a global measure of corticospinal excitability.

RESULTS

No significant differences in baseline GABAA receptor availability or cortical excitability were found between patients and controls. Additionally, no correlations were observed between baseline measurements of GABAA receptor availability and TMS outcomes. Changes in GABAA receptor availability in the hand motor cortex, between pre- and post-assessments, were inversely related to pre-post changes in hand rMT.

CONCLUSION

We found that a change in GABAA receptor availability was inversely related to a change in rMT, suggesting a link between GABA deficiency and increased rMT previously observed in depressive episodes. The results highlight the complex mechanisms governing cortical excitability measures and offer new insight into their properties during the depressive state.

Psychometric properties of the Clinical Assessment Interview for Negative Symptoms (CAINS) in patients with depression and its relationship to affective symptoms

BACKGROUND

There is a conceptual overlap between negative and depressive symptoms, requiring further exploration to advance the understanding of negative symptoms. The aim of this study was to examine psychometric properties of the Clinical Assessment Interview for Negative Symptoms (CAINS) in patients with depression, and to explore the relationship between the negative and affective symptoms domains.

METHODS

Fifty-one patients with a depressive episode were included and interviewed with the CAINS and the Brief Psychiatric Rating Scale-Expanded (BPRS-E). Self-reported depressive symptoms were collected with the Montgomery-Asberg Depression Rating Scale (MADRS-S). Inter-rater agreement, internal consistency and validity measures were examined, as were correlations between negative and affective symptoms.

RESULTS

The intraclass correlation for the CAINS motivation and pleasure subscale (CAINS-MAP) was 0.98 (95% CI 0.96-0.99) and that for the expressional subscale (CAINS-EXP) was 0.81 (95% CI 0.67-0.89). Cronbach's alpha was 0.71 (95% CI 0.57-0.82) for the CAINS-MAP and 0.86 (95% CI 0.79-0.92) for the CAINS-EXP. The correlation with the negative symptoms subscale of the BPRS-E was 0.35 (p = 0.011, blinded/different raters) or 0.55 (p < 0.001, not blinded/same rater). The CAINS-MAP correlated with the affective symptoms subscale of the BPRS-E (r = 0.39, p = 0.005) and the MADRS-S total score (r = 0.50, p < 0.001), but not with anxiety symptoms.

CONCLUSIONS

Negative symptoms in depression can be assessed with the CAINS with good inter-rater agreement and acceptable internal consistency and validity. There are associations between negative and depressive symptoms that call for further exploration.

The association between exposure to clozapine, olanzapine, and quetiapine and the outcomes perimyocarditis and heart failure: A population-based cohort study

The risk of cardiac adverse events following clozapine use is debated and is unknown for the chemically related and widely used antipsychotics olanzapine and quetiapine. National Swedish registers were used to identify all patients 16-75 years old with antipsychotic dispensations between 2005 and 2018. The short-term outcome was a diagnosis of perimyocarditis (pericarditis and/or myocarditis) within two months of first dispensation, and the long-term outcome was heart failure (including cardiomyopathy) within three years. Cox regressions with time varying exposure were used to estimate hazard rates (HR) and their 95% confidence intervals (CI). A total of 201,045 individuals were included in the cohort. The risk of developing perimyocarditis during clozapine treatment tripled compared to no antipsychotic treatment (HR 3.4, CI 1.6-7.3), although the absolute rate remained comparably low. The long-term risk of heart failure during clozapine treatment was also elevated (HR 1.3, CI 1.1-1.7). Treatment with either or both olanzapine or quetiapine was not associated with an increased relative risk of perimyocarditis, or heart failure compared to no antipsychotic treatment. Clozapine use is therefore associated with a substantially elevated short-term risk of perimyocarditis and an increased risk of heart failure within three years.

Outcome of transcranial magnetic intermittent theta-burst stimulation in the treatment of depression - A Swedish register-based study

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) is an established treatment of depression. The more recently introduced intermittent Theta-burst stimulation (iTBS) has shown significant superiority over sham-stimulation and equal effect sizes to a 10 Hz protocol in one clinical trial. The aim of the current study was to investigate the effectiveness and tolerability of iTBS in a naturalistic, clinical setting. Further, we explored demographical and clinical predictors of response.

METHODS

Data was collected from seventeen rTMS-sites in Sweden between January 2018 and May 2021, through the Swedish National Quality register for repetitive Transcranial Magnetic Stimulation (Q-rTMS). We included 542 iTBS-treated patients with unipolar or bipolar depression. Outcome was assessed with Clinical Global Impression Severity and Improvement scores in an intention to treat analysis.

RESULTS

The response rate was 42.1 % and 16.1 % reached remission. The response rate was significantly larger in the oldest age group compared to the youngest (odds ratio 3.46, 95 % confidence interval 1.65-7.22). Less severe level of depression (Montgomery-Åsberg depression rating scale self-assessment < 36) at baseline predicted response and remission. Only <1 % were much or very much worse after treatment. Drop-out rate was 10.9 %. No serious adverse events were reported.

LIMITATIONS

Retrospective analysis of register data. No comparison group.

CONCLUSIONS

In a clinical setting, iTBS was shown to be safe and tolerable and the response rate was similar to that reported from clinical trials. Older age-group and less severe illness predicted response.

No effects on heart rate variability in depression after treatment with dorsomedial prefrontal intermittent theta burst stimulation

Background: The purpose of this study was to investigate whether treatment of a depressive episode with intermittent theta burst stimulation (iTBS) over the dorsomedial prefrontal cortex (DMPFC) had any effects on heart rate variability (HRV). We also investigated if changes in HRV covaried with symptom change after iTBS and if HRV could predict symptom change. Methods: We included 49 patients with a current depressive episode. All were randomized to receive a double-blind treatment course with active or sham iTBS over the DMPFC. HRV data were obtained from 1 h of night data before and after the iTBS. The standard deviation of the RR interval (SDNN) was chosen as primary outcome measure. Depressive, negative, and anxiety symptoms as well as self-rated health were assessed by clinicians or by self-report. Results: The group×time linear mixed model revealed no effect of iTBS on SDNN (estimate = −1.8, 95% confidence interval [CI]: −19.9 to 16.2). There were neither correlations between HRV and depressive, negative, or anxiety symptom change after iTBS nor with self-assessed health. No predictive value of HRV was found. Conclusions: Treatment for depression with dorsomedial iTBS had neither negative nor positive effects on the cardiac autonomic nervous system.

Response to electroconvulsive therapy in treatment-resistant depression: nationwide observational follow-up study

BACKGROUND

Previous studies have not investigated response rates after electroconvulsive therapy (ECT) in patients with non-psychotic treatment-resistant depression (TRD).

AIMS

To assess and compare the response rate of ECT for patients with TRD and non-TRD, in a large and clinically representative patient sample.

METHOD

Patients aged ≥18 years, who were treated for a unipolar, non-psychotic depressive episode with at least one ECT session as part of a first-time, index ECT series between 1 January 2011 and 31 December 2017 were included from the Swedish National Quality Register for ECT. Patients who had initiated a third consecutive trial of antidepressants or add-on medications before start of ECT were classified as having TRD. Patients not meeting criteria for TRD were classified as non-TRD. The main outcome was response to ECT according to the Clinical Global Impressions - Improvement Scale (CGI-I), scored as 1 or 2 ('very much' or 'much improved' after ECT, respectively). Logistic regression was used to compare outcome measures between TRD and non-TRD, adjusting for potential confounders.

RESULTS

A total of 4244 patients were included. Of these, 1121 patients had TRD and 3123 patients had non-TRD. The CGI-I response rate was 65.9% in the TRD group compared with 75.9% in the non-TRD group (adjusted odds ratio 0.64, 95% CI 0.54-0.75). Older age and more severe depression were predictors of response in patients with TRD.

CONCLUSIONS

A clear majority of patients with TRD, as well as patients with non-TRD, responded to ECT, although the response rate was somewhat lower for TRD.

Intercorrelation of physiological seizure parameters and hormonal changes in electroconvulsive therapy

OBJECTIVE

Physiological parameters that predict electroconvulsive therapy (ECT) effectiveness may reflect propagation of the induced epileptic seizure. As an indication of seizure propagation to the diencephalon, we here examined the correlation between prolactin increase after ECT and clinical seizure evaluation parameters, focusing on peak heart rate. As a proxy for peripheral endocrine stress response, we examined the correlation to postictal cortisol increase.

METHODS

Participants were consecutively recruited from clinical ECT patients (n = 131, age 18-85 years). The first ECT session in a series was examined. For each participant, blood serum concentrations of prolactin and cortisol were measured immediately before and within 30 min after the seizure. Physiological parameters were extracted from clinical records: peak heart rate (HR) during seizure, electroencephalography (EEG) seizure duration, and motor seizure duration. Correlations were calculated using non-parametric tests.

RESULTS

Serum prolactin increased after ECT and correlated with peak HR, EEG seizure duration, and motor seizure duration. Peak HR during seizure also correlated positively with both EEG seizure duration and motor seizure duration. Correlations were unaffected by age, sex, baseline prolactin levels, antipsychotics, or beta-blocking agents. Serum cortisol increased after ECT but did not correlate with the seizure evaluation parameters, nor with prolactin concentrations.

CONCLUSIONS

Our findings of a positive correlation between peak HR and prolactin that was independent from the peripheral endocrine stress response might be in line with the idea that tachycardia during ECT seizures reflects seizure propagation to the diencephalon. This supports the practice of monitoring cardiovascular response for ECT seizure evaluation.

Application of positron emission tomography in psychiatry-methodological developments and future directions

Mental disorders represent an increasing source of disability and high costs for societies globally. Molecular imaging techniques such as positron emission tomography (PET) represent powerful tools with the potential to advance knowledge regarding disease mechanisms, allowing the development of new treatment approaches. Thus far, most PET research on pathophysiology in psychiatric disorders has focused on the monoaminergic neurotransmission systems, and although a series of discoveries have been made, the results have not led to any material changes in clinical practice. We outline areas of methodological development that can address some of the important obstacles to fruitful progress. First, we point towards new radioligands and targets that can lead to the identification of processes upstream, or parallel to disturbances in monoaminergic systems. Second, we describe the development of new methods of PET data quantification and PET systems that may facilitate research in psychiatric populations. Third, we review the application of multimodal imaging that can link molecular imaging data to other aspects of brain function, thus deepening our understanding of disease processes. Fourth, we highlight the need to develop imaging study protocols to include longitudinal and interventional paradigms, as well as frameworks to assess dimensional symptoms such that the field can move beyond cross-sectional studies within current diagnostic boundaries. Particular effort should be paid to include also the most severely ill patients. Finally, we discuss the importance of harmonizing data collection and promoting data sharing to reach the desired sample sizes needed to fully capture the phenotype of psychiatric conditions.

Modulation of dorsolateral prefrontal cortex functional connectivity after intermittent theta-burst stimulation in depression: Combining findings from fNIRS and fMRI

BACKGROUND

Resting-state functional magnetic resonance imaging (fMRI) can assess modulation of functional connectivity networks following repetitive transcranial magnetic stimulation (rTMS) in the treatment of depression. Functional near-infrared spectroscopy (fNIRS) is well suited for the concurrent application during rTMS treatment sessions to capture immediate blood oxygenation (oxy-Hb) effects, however limited in spatial resolution.

OBJECTIVE

To understand the network effects behind such a prefrontal fNIRS response during rTMS, and to test whether the fNIRS signal may be predictive of treatment response, we linked data from fNIRS and fMRI within a clinical intervention study.

METHODS

42 patients with ongoing depression were recruited and randomized to receive active or sham intermittent theta-burst stimulation (iTBS) over the dorsomedial prefrontal cortex (dmPFC) twice daily for ten days at target intensity. Oxy-Hb was recorded with fNIRS during the first, fifth, and final day of iTBS, with the probe holders located laterally to the TMS coil over regions corresponding to the left and right dorsolateral prefrontal cortex (dlPFC). Resting-state fMRI scanning was performed before and after the whole iTBS treatment course. Functional connectivity analyses were then performed using dlPFC seeds from parcels of a brain atlas showing most overlap with the fNIRS probe locations during treatment.

RESULTS

After active iTBS, left dlPFC-connectivity to the right insula/operculum was reduced compared to sham. The left insula showed a connectivity reduction to the left dlPFC that correlated with an improvement in symptoms. In addition, the posterior parietal cortex showed a connectivity reduction to the left dlPFC that correlated with the fNIRS signal following active iTBS. Finally, the fNIRS oxy-Hb signal from the left dlPFC-seed during the first treatment day was predictive of dlPFC-connectivity change to precentral and temporal cortex regions.

CONCLUSION

By linking findings from these two different methods, this study suggests that changes within both the salience network and the central executive network affect the fNIRS response to iTBS.

A blinded validation of the Swedish version of the Clinical Assessment Interview for Negative Symptoms (CAINS)

PURPOSE

The Clinical Assessment Interview for Negative Symptoms (CAINS) was developed in order to advance the assessment of negative symptoms. The aim of this study was to validate the Swedish version of the CAINS.

MATERIALS AND METHODS

Thirty-four out-patients with a schizophrenia spectrum disorder were recruited. All patients were videotaped while interviewed with the CAINS and the Brief Psychiatric Rating Scale (BPRS). Another rater watched the video recordings in the reverse order, enabling a blinded design. The patients also filled in self-reported measures of depression, quality of life, and social and vocational functioning. We calculated inter-rater agreement and internal consistency for the CAINS. We also calculated validity measures by correlating the subscales Motivation and Pleasure (CAINS-MAP) and Expression (CAINS-EXP) to subscales of the BPRS.

RESULTS

The blinded inter-rater agreement for the CAINS total score was high (ICC = 0.92) but slightly lower for the expression subscale (ICC = 0.76). Cronbach's alpha was 0.84 for the total score. Convergent validity with the negative symptoms subscale of BPRS was different for the blinded and the unblinded data, with a CAINS-MAP correlation of 0.10 (p = 0.580) and a CAINS-EXP correlation of 0.48 (p = 0.004) in the blinded data. The unblinded data had a CAINS-MAP correlation of 0.38 (p = 0.026) and a CAINS-EXP correlation of 0.87 (p < 0.001). Self-rated measures of anhedonia correlated to CAINS-MAP with a coefficient of 0.68 (p < 0.001), while the CAINS-EXP only had a correlation of 0.16 (p = 0.366) to these measures.

CONCLUSION

The Swedish version of the CAINS displays adequate psychometric properties in line with earlier validation studies.

Suppressing visual hallucinations in an adolescent by occipital transcranial magnetic stimulation: A single-case experimental research design

Visual hallucinations after central or peripheral impairment, commonly called Charles Bonnet syndrome, are often highly distressing and with few available treatment options. Here we report a case where an adolescent developed severely distressing visual hallucinations after hypoxic damage to the occipital cortex following a suicide attempt. The patient received active and sham occipital continuous theta-burst stimulation (cTBS) in a single-case experimental research design and a subsequent open phase, to evaluate cTBS as a Charles Bonnet treatment. The visual hallucinations seemed to decrease more during active than sham cTBS in the blind phase, and in the following week of repeated five daily treatments they almost disappeared. A normalization of increased activity in the lateral visual network after cTBS was observed on a functional magnetic resonance imaging resting-state analysis compared with 42 healthy controls. Visual evoked potentials stayed largely unchanged both in the sham-controlled blind phase and the subsequent open phase. During the two weeks after the open phase with repeated cTBS sessions, the visual hallucinations gradually reappeared and almost returned to the baseline level. Our findings suggest that active cTBS over the primary visual cortex can reduce visual hallucinations through modulation of downstream visual regions, though the effect is temporally limited.

Habitual caffeine consumption moderates the antidepressant effect of dorsomedial intermittent theta-burst transcranial magnetic stimulation

BACKGROUND

Potentiating current antidepressant treatment is much needed. Based on animal studies, caffeine may augment the effects of currently available antidepressants.

OBJECTIVE

Here, we tested whether habitual caffeine consumption moderates the antidepressant effects of repetitive transcranial magnetic stimulation (rTMS) using intermittent theta-burst stimulation (iTBS).

METHODS

Forty patients with current depressive episodes were randomized to active iTBS (n = 19) or sham treatment (n = 21; shielded side of the coil and weak transcutaneous electrical stimulation) delivered two times per day for 10-15 weekdays. Neuronavigated stimulation was applied to the dorsomedial prefrontal cortex. Symptom improvement was measured using change in self-reported Montgomery-Åsberg Depression Rating Scale (MADRS) scores. Pretreatment habitual caffeine consumption was quantified using self-reports of number of cups of coffee and energy drinks consumed the 2 days before the treatment starts.

RESULTS

Habitual caffeine consumption was associated with symptom improvement following active iTBS (r = 0.51, 95% confidence interval (CI): 0.08-0.78, p = 0.025) but not following sham treatment (r = -0.02, 95% CI: -0.45 to 0.42, p = 0.938). A multiple regression analysis corroborated the findings by showing a significant caffeine consumption × treatment group interaction (β = 0.62, p = 0.043), but no main effects of treatment group (β = 0.22, p = 0.140) or caffeine consumption (β = -0.01, p = 0.948). No group differences in pretreatment symptom scores or caffeine consumption were detected (p values > 0.86).

CONCLUSION

Habitual caffeine consumption moderated the antidepressant effect of dorsomedial iTBS, consistent with caffeine improving antidepressant pharmacological treatments in animals. Caffeine is an antagonist of adenosine receptors and may enhance antidepressant effects through downstream dopaminergic targets.

Inhibitory and excitatory neurotransmitter systems in depressed and healthy: A positron emission tomography and magnetic resonance spectroscopy study

The Gamma-aminobutyric acid (GABA) and glutamate (Glu) neurotransmitter systems are implicated in depression. While previous studies found reduced GABA levels, and a tendency towards reduced Glu, using proton (¹H) magnetic resonance spectroscopy (¹H-MRS), little is known about GABA_A receptor availability in depression. Here, the aim was to characterize GABA and Glu-levels in dorsal anterior cingulate cortex (dACC), whole-brain GABA_A availability, and their relationship in patients with depression compared to healthy controls. Forty-two patients and 45 controls underwent ¹H-MRS using a MEGA-PRESS sequence to quantify dACC GABA+ and Glu (contrasted against creatine [Cr]). Immediately preceding the ¹H-MRS, a subsample of 28 patients and 15 controls underwent positron emission tomography (PET) with [¹¹C]Flumazenil to assess whole-brain GABA_A receptor availability. There were no differences in dACC GABA+/Cr or Glu/Cr ratios between patients and controls. The same was true for whole-brain GABA_A receptor availability. However, there was a significant negative relationship between GABA+/Cr ratio and receptor availability in ACC, in a whole-brain voxel-wise analysis across patients and controls, controlling for group or depressive symptoms. This relatively large study did not support the GABA-deficit hypothesis in depression, but shed light on GABA-system functioning, suggesting a balance between neurotransmitter concentration and receptor availability in dACC.

Response rate and subjective memory after electroconvulsive therapy in depressive disorders with psychiatric comorbidity

BACKGROUND

Response rates after and tolerability of electroconvulsive therapy (ECT) in depressive disorders with psychiatric comorbidity are uncertain.

METHODS

Data on patients with a depressive episode and a first course of ECT were collected from the Swedish National Quality Register for ECT. Logistic regression analyses, adjusted for gender, age, and depressive episode severity, were used to compare patients with and without comorbidity. The clinical response assessment Clinical Global Impression - Improvement Scale was used in 4413 patients and the memory item from the Comprehensive Psychiatric Rating Scale was used for subjective memory impairment rating after ECT in 3497 patients.

RESULTS

In patients with depressive disorder and comorbid personality disorder or anxiety disorder, 62.7% and 73.5%, respectively, responded after ECT compared with 84.9% in patients without comorbidity [adjusted odds ratio (aOR) 0.43, 95% confidence interval (CI) 0.34-0.55, and aOR 0.61, 95% CI 0.51-0.73, respectively]. The proportion of responding patients with comorbid alcohol use disorder was 77.1%, which was not significantly different from that in patients without comorbidity (aOR 0.75, 95% CI 0.57-1.01). The impact of comorbidity decreased with higher age and depressive episode severity. Subjective ratings of memory impairment did not differ between patients with and without comorbidity.

LIMITATIONS

Observational non-validated clinical data.

CONCLUSIONS

The response rate after ECT in depression may be lower with concurrent personality disorder and anxiety disorder; however, the majority still respond to ECT. This implies that psychiatric comorbidity should not exclude patients from ECT.

Dorsomedial prefrontal theta burst stimulation to treat anhedonia, avolition, and blunted affect in schizophrenia or depression - a randomized controlled trial

BACKGROUND

Intermittent theta burst stimulation (iTBS) over the dorsomedial prefrontal cortex (DMPFC) has shown promise in open-label trials of depression.

METHODS

In this randomized, double-blind, sham controlled trial we evaluate iTBS over the DMPFC for anhedonia, avolition, and blunted affect in patients with schizophrenia or depression. Active iTBS was delivered over the DMPFC with 1200 pulses per session, twice daily over ten weekdays at target intensity with an angled figure-of eight coil. Sham condition comprised the magnetically shielded side of the coil and simultaneous transcutaneous electrical nerve stimulation. Primary outcome was change on the Clinical Assessment Interview for Negative Symptoms (CAINS).

RESULTS

Twenty-eight patients were randomized to active iTBS and 28 to sham. Mean (standard deviation) change in CAINS score from baseline to the day after last treatment was -5.3 (8.1) in active iTBS and -2.1 (7.1) in sham. A linear model showed no significant effect of treatment, accounting for baseline scores p=.088. Sub analyses per diagnostic group showed a significant effect in patients with depression, p=.038, but not in the schizophrenia group, p=.850. However, overall depressive symptoms did not change significantly in patients with depression. There were three serious adverse events, all in the sham group.

LIMITATIONS

Possibly too short treatment course and few patients with schizophrenia.

CONCLUSION

In this first transdiagnostic randomized controlled trial of iTBS over DMPFC for anhedonia, avolition, and blunted affect it can be concluded that it was generally tolerable and safe but only more effective than sham in the subgroup of patients with depression.

Risk of Delayed Discharge and Reoperation of Gastric Bypass Patients with Psychiatric Comorbidity-a Nationwide Cohort Study

BACKGROUND

Gastric bypass (GBP) surgery is considered a safe and effective treatment for obesity. However, there is uncertainty regarding the impact of preexisting psychiatric comorbidity on GBP complications. We have investigated whether a psychiatric diagnosis before GBP surgery is associated with delayed discharge (the odds of being in the 90th percentile of length of stay) and rate of reoperation in a nationwide Swedish cohort.

METHODS

Patients undergoing GBP surgery during 2008-2012 were identified and followed up through the National Patient Register and the Prescribed Drug Register. Logistic regression models were fitted to the studied outcomes.

RESULTS

Among the 22,539 patients identified, a prior diagnosis of bipolar disorder, schizophrenia, depression, neurotic disorders, ADHD (attention deficit hyperactivity disorder), substance use disorder, eating disorder, personality disorder, or self-harm since 1997 (n = 9480) was found to be associated with delayed discharge after GBP surgery (odds ratio [OR] = 1.47, confidence interval [CI] 1.34-1.62), especially in patients with psychiatric hospitalization exceeding 1 week in the 2 years preceding GBP surgery (OR = 2.06, CI 1.30-3.28), compared with those not hospitalized within psychiatry. Likewise, patients with a prior psychiatric diagnosis were more likely to be reoperated within 30 days (OR = 1.25, CI 1.11-1.41), with twice the likelihood OR 2.23 (CI 1.26-3.92) for patients with psychiatric hospitalization of up to a week in the 2 years preceding GBP surgery, compared with patients who had not been hospitalized within psychiatry.

CONCLUSIONS

A psychiatric diagnosis before GBP surgery was associated with delayed discharge and increased likelihood of reoperation within 30 days. Patients with a prior psychiatric diagnosis may, therefore, need additional attention and support.

Modulation of the prefrontal blood oxygenation response to intermittent theta-burst stimulation in depression: A sham-controlled study with functional near-infrared spectroscopy

OBJECTIVE

To better understand the neural mechanisms behind the effect of intermittent theta-burst stimulation (iTBS), we investigated how the prefrontal blood oxygenation response measured by changes in oxygenated haemoglobin (oxy-Hb) was modulated during a sham-controlled iTBS treatment course, and whether this was related to depressive symptom change.

METHODS

In this randomised, double-blind study, patients with ongoing treatment-resistant depression received either active (n = 18) or sham (n = 21) iTBS over the dorsomedial prefrontal cortex for ten to fifteen days with two sessions daily. Event-related functional near-infrared spectroscopy (fNIRS) was measured during each iTBS train, and resting-state oxy-Hb was compared before and after each iTBS session at the first, fifth, and last treatment day.

RESULTS

Patients receiving active iTBS had an increase of the event-related oxy-Hb response compared to the sham group on the fifth (bilateral prefrontal cortices p < .001) and last (left prefrontal p = .007, right prefrontal p = .025) treatment day. Resting-state analysis showed suppressed oxy-Hb change in active iTBS compared to sham iTBS on the last treatment day (p = .024). Oxy-Hb change was unrelated to depressive symptom change (p = .474).

CONCLUSIONS

This study describes a modulation of the blood oxygenation response over the prefrontal cortex that was built up during the course of active iTBS treatment in depression.

Unchanged Cognitive Performance and Concurrent Prefrontal Blood Oxygenation After Accelerated Intermittent Theta-Burst Stimulation in Depression: A Sham-Controlled Study

Aim: Intermittent theta-burst stimulation (iTBS) delivered over the dorsomedial prefrontal cortex (DMPFC) has shown promise as a treatment for anhedonia and amotivation in patients with depression. Here, we investigated whether this protocol modulates cognitive performance and concurrent prefrontal blood oxygenation. We also examined whether depressed patients exhibit cognitive dysfunction and prefrontal hypoactivity at baseline compared to healthy controls. Methods: This sham-controlled study comprises 52 patients randomized to either active or sham accelerated iTBS over the DMPFC (applied twice daily) for 10 consecutive treatment days, and 55 healthy controls. Cognitive performance was assessed at baseline and once again 4 weeks later using a cognitive test battery targeting attention, inhibitory control, and numerical, verbal, and visual working memory. Concurrent prefrontal oxygenated hemoglobin (oxy-Hb) was captured with functional near-infrared spectroscopy. Results: Active iTBS over DMPFC did not affect cognitive performance or concurrent oxy-Hb change compared to sham iTBS in patients with depression. Compared to controls, patients at baseline showed impaired performance in the Trail Making Test, the Rey Auditory Verbal Learning Test, the Animal Naming Test, and the Digit Symbol Substitution Test, however no difference in prefrontal oxy-Hb was observed. Conclusion: Patients with treatment-resistant depression displayed cognitive deficits, however without prefrontal hypoactivity, compared to healthy controls at baseline. iTBS treatment did not alter cognitive performance, nor concurrent prefrontal blood oxygenation, in patients. Taken together, iTBS can likely be considered a cognitively safe treatment option in this sample of patients.

A register-based approach to identifying treatment-resistant depression-Comparison with clinical definitions

BACKGROUND

Several definitions of treatment-resistant depression (TRD) are used for clinical research, but no verified model for use in register data exists. We aimed to compare a novel model created for use in register data-the Karolinska Institutet Model (KIM)-to the clinical definitions regarding the proportion of patients identified with TRD, their characteristics and clinical outcomes.

METHODS

All patients in Sweden initiating antidepressant treatment with a diagnosis of depression in specialized healthcare 2006-2014 were identified and followed in national registers. In KIM, patients who initiated a third sequential, >28-day antidepressant treatment trial were defined as having TRD. Proportion of TRD and patient characteristics were compared with register adaptations of the European Staging Model (ESM), Massachusetts General Hospital Staging Method (MGH-s), and Maudsley Staging Model (MSM). Differences in patient characteristics were assessed with Chi-square tests and one-way ANOVAs. Hazard ratios for psychiatric hospitalization and for death from external causes were estimated by Cox proportional hazard regressions.

RESULTS

Out of 127,108 antidepressant initiators with depression, the highest proportion of TRD was found using the MGH-s (19.0%), followed by MSM (15.3%), KIM (12.9%), and ESM (9.5%). Clinical characteristics were similar across the models. Compared with TRD patients identified by KIM, those identified by ESM had a marginally higher risk for psychiatric hospitalization (adjusted hazard ratio [aHR] 1.03, 95%CI 1.00-1.05), whereas those identified by MGH-s (aHR 0.92; 0.90-0.94) and MSM (aHR 0.95; 0.94-0.97) had a slightly reduced risk. Patients identified by MGH-s showed a reduced mortality compared with KIM (aHR 0.84; 0.72-0.98).

CONCLUSIONS

This study provides insight into the differing characteristics of patients captured by various TRD models when used for register research. Models yielding lower proportions of TRD seemed to identify patients with greater morbidity. The KIM may be useful for register based research in TRD.

Lithium influences whole-organism metabolic rate in Drosophila subobscura

Lithium is widely used to treat bipolar disorder. However, the efficacy and vulnerability as to its side effects are known to differ. Although the specific biochemical mechanism of action is still elusive, lithium may influence mitochondrial function, and consequently, metabolism. Lithium exposure in this study was conducted on a unique set of mito-nuclear introgression lines of Drosophila subobscura to disentangle the independent effects of mitochondrial DNA (mtDNA) against a common nuclear DNA background. The study addressed three issues: (a) whether lithium has a dose-dependent effect on whole-organism metabolic rate, (b) whether mtDNA haplotypes show divergent metabolic efficiency measured by metabolic rate to lithium exposure and (c) whether lithium influences the whole-organism metabolic rate across sexes. The results confirm that lithium influenced the whole-organism metabolic rate, showing a subtle balance between efficacy and adverse effects within a narrow dose range. In addition, lithium exposure was found to influence metabolism differently based on mtDNA haplotypes and sex. This preliminary research may have a range of biological implications for the role of mitochondrial variability in psychiatric disease and treatment by contributing to the understanding and predicting of the lithium treatment response and risk for toxic side effects.