Efficacy of functional magnetic resonance imaging-guided personalized repetitive transcranial magnetic stimulation (fMRI-rTMS) in depressive patients with emotional blunting: study protocol for a randomized controlled trial

BACKGROUND

Emotional blunting is a symptom that has always been present in depressed patients. Repetitive transcranial magnetic stimulation (rTMS) is a safe and effective supplementary therapy for treating depression. However, the effectiveness and brain imaging processes of functional magnetic resonance imaging-guided personalized rTMS (fMRI-rTMS) in the treatment of depression with emotional blunting have not been observed in randomized controlled trials.

METHODS

This study is a randomized, controlled, double-blind, and single-center clinical trial in which 80 eligible depressed patients with emotional blunting will be randomly assigned to two groups: a functional magnetic resonance imaging-guided personalized rTMS (fMRI-rTMS) group and a control group. Individuals in the fMRI-rTMS group (n = 40) will receive high-frequency rTMS (10 Hz, 120% MT). The main target of stimulation will be the area most relevant to the functional connectivity of the right medial prefrontal cortex (mPFC) and amygdala. The control group (n = 40) will receive sham stimulation, with a coil flipped to 90 degrees relative to the vertical scalp. All patients will receive 15 consecutive days of treatment, with each session lasting half an hour per day, followed by 8 weeks of follow-up. The primary outcome is the comparison of Oxford Depression Questionnaire (ODQ) scores between these two groups at different time points. The secondary outcomes include evaluating other clinical scales and assessing the differences in brain imaging changes between the two groups before and after treatment.

DISCUSSION

This trial aims to examine the effects of functional magnetic resonance imaging-guided personalized rTMS (fMRI-rTMS) intervention on depressed patients experiencing emotional blunting and to elucidate the potential mechanism behind it. The results will provide new evidence for using fMRI-rTMS in treating depression with emotional blunting in the future.

TRIAL REGISTRATION

ClinicalTrials.gov INCT05555940. Registered on 13 September 2022 at http://clinicaltrials.gov .

Does partial blockade of dopamine D2 receptors with Amisulpride cause anhedonia? An experimental study in healthy volunteers

BACKGROUND

Anhedonia is a frequent cause of functional im^pairment in psychosis. Although it is plausible that medication-induced D2 receptor blockade could diminish hedonic responding, there is little experimental research testing this hypothesis in humans.

METHODS

To inspect possible effects of partial D2 blockade on hedonic experiences, we administered 300 mg of Amisulpride or placebo to 85 participants in a randomized, double-blind, placebo-controlled trial. Participants were then subjected to an emotional evocation task utilizing standardized pictorial pleasant, neutral, and unpleasant stimuli.

RESULTS

We observed lower positivity ratings in the Amisulpride group compared to placebo across all stimulus categories (p = .026, f = 0.25) and no group differences in negativity or arousal ratings. The Amisulpride group also showed lower electrodermal responses across all stimulus categories compared to placebo (p = .017, f = 0.27). The electrodermal response was especially diminished for pleasant stimuli.

CONCLUSION

We interpret our findings as evidence that D2 blockade via Amisulpride can reduce at-the-moment hedonic responsivity in healthy volunteers. If these results can be confirmed in drug-naïve clinical samples, this would indicate that antipsychotic medication contributes to clinical anhedonia, probably via antagonistic effects at the dopamine D2 receptor.

Reliability and validity of the Chinese version of the Oxford Depression Questionnaire (ODQ-Chinese)

BACKGROUNDS

Emotional blunting is regularly reported in depressed patients on antidepressant treatment. It is uncertain whether this phenomenon represents residual symptoms of depression or side-effects of antidepressant treatment. At present, there is no adequate instrument to measure this phenomenon in China. This study aimed to test the reliability and validity of the Chinese version of The Oxford Depression Questionnaire (ODQ-Chinese).

METHODS

The study sample comprised of 312 patients with major depressive disorder. All participants were assessed with the ODQ-Chinese, the Beck Depression Inventory-13 (BDI-13), the UKU side effects rating scale (UKU-SERS), and the 'gold standard' question related to the participant's experience of emotional side-effects. 20 % of the participants completed the ODQ-Chinese and BDI-13 within 1 or 2 weeks after the initial assessment.

RESULTS

The Cronbach α statistic was 0.91 for the ODQ-Chinese. It had good split-half reliability. The scale showed excellent test-retest reliability and demonstrated significant correlation with the BDI-13. The sensitivity and specificity for detecting emotional side-effects according to patients' responses to the "gold standard" question were 69 % and 67 % for a cutoff point ≥ 13 of Antidepressant as the cause (AC) domain, AUCs was 0.74 (95 % CI: 0.68-0.79).

CONCLUSION

In conclusion, the results of this study indicate that the Chinese version of the ODQ has good validity and reliability. It is an effective self-report measure of emotional blunting symptoms of depression.

Part IV: differences between patient and physician perceptions

BACKGROUND

Emotional blunting is common in patients with depression. An online survey was undertaken to assess the experience of emotional blunting, and its impact on functioning and quality of life, in the acute and remission phases of depression from the perspective of patients and healthcare providers (HCPs). This paper presents data on the level of concordance between patient and HCP perspectives.

METHODS

This was a cross-sectional, observational study. Patient respondents were adults with a diagnosis of depression, who were currently using a prescribed antidepressant, and who reported emotional blunting during the past 6 weeks. HCPs completed the survey for the last two eligible patients they had seen, one in each phase of depression. Assessments included the Oxford Depression Questionnaire (ODQ) 'antidepressant as cause' domain and the Functioning Assessment Short Test (FAST).

RESULTS

Mean ODQ 'antidepressant as cause' domain scores were significantly higher in the patient-reported cohort (n = 752) than in the HCP-assessed cohort (n = 766) in both the acute (18.0 vs 12.5, respectively; p < 0.01) and remission phases (17.6 vs 12.6; p < 0.01). Overall, 45% of patients believed that their antidepressant medication was negatively affecting their emotions and 39% were considering stopping or had stopped their antidepressant because of perceived emotion-related side effects. In the HCP-assessed cohort, the antidepressant was considered responsible for emotional blunting in 30% of patients and only 18% of patients were believed to be considering stopping their medication due to emotional blunting. Patients reported a greater impact of emotional blunting on activities of daily living than HCPs. Mean FAST score was significantly higher in each phase of depression in the patient-reported cohort than in the HCP-assessed cohort (acute phase, 47.0 vs 39.1; remission phase, 33.5 vs 19.4; both p < 0.01).

CONCLUSIONS

Compared with previous studies, our results suggest that HCPs may underestimate the prevalence of emotional blunting in patients with depression. HCPs also appear to underestimate the severity and impact of emotional blunting on patient functioning and treatment adherence compared with patients' own perspectives. Differences between patient and HCP perspectives were most pronounced during the acute phase of the disease.

Part III: relationship with psychological trauma

BACKGROUND

This international online survey investigated the experience and impact of emotional blunting in the acute and remission phases of depression from the perspective of patients and healthcare providers (HCPs). This paper presents data on the history and severity of psychological trauma and its potential impact on emotional blunting in major depressive disorder (MDD); differences between patient and HCP perceptions are explored.

METHODS

Patient respondents (n = 752) were adults with a diagnosis of depression who were currently taking antidepressant therapy and reported emotional blunting during the past 6 weeks. HCPs provided details on two eligible patients: one in the acute phase of depression and one in remission from depression (n = 766). Trauma was assessed using questions based on the Childhood Trauma Questionnaire; emotional blunting was assessed using the Oxford Depression Questionnaire (ODQ). Multivariate regression analyses were applied to examine the relationship between trauma and ODQ score.

RESULTS

A history of any childhood or recent traumatic event was reported by 97% of patients in the self-assessed cohort and for 83% of those in the HCP-assessed cohort (difference, p < 0.01). Patients were more likely than HCPs to feel that this trauma had contributed to their/the patient's depression (58% vs 43%, respectively; p < 0.01) and that the depression was more severe because of trauma (70% vs 61%, respectively; p < 0.01). Emotional blunting was significantly worse in patients who reported severe trauma than in those who had not experienced severe trauma (mean total ODQ score, 90.1 vs 83.9, respectively; p < 0.01). In multivariate regression analyses, experiencing both severe childhood and recent trauma had a statistically significant impact on ODQ total score (p = 0.001).

CONCLUSIONS

A high proportion of patients with depression and emotional blunting self-reported exposure to childhood and/or recent traumatic events, and emotional blunting was more severe in patients who reported having experienced severe trauma. However, history of psychological trauma in patients with MDD appeared to be under-recognized by HCPs. Improved recognition of patients who have experienced psychological trauma and are experiencing emotional blunting may permit more targeted therapeutic interventions, potentially resulting in improved treatment outcomes.

Part II: relationship with functioning, well-being, and quality of life

BACKGROUND

Emotional blunting is a common symptom in people with depression and an important factor preventing full functional recovery. This international survey investigated the experience of emotional blunting in the acute and remission phases of depression from the perspective of patients and healthcare providers. This paper presents data on the impact of emotional blunting on overall functioning and health-related quality of life from the patient perspective.

METHODS

Respondents were adults diagnosed with depression by a physician, currently prescribed an antidepressant, and reporting emotional blunting during the past 6 weeks. Assessments included the Oxford Depression Questionnaire (ODQ), the Functioning Assessment Short Test (FAST), and the World Health Organization-Five Well-being Index (WHO-5). Pearson correlation and multivariate regression analyses were applied to examine the relationship between ODQ and FAST scores.

RESULTS

Data are available for 752 patients (62% female; mean age, 45 years). Mean ODQ total score was 94.8 in patients in the acute phase of depression (n = 300) and 85.7 in those in remission (n = 452; possible maximum, 130). Mean FAST total scores were 47.0 and 33.5, respectively (possible maximum, 72). Patients in the acute phase of depression had significantly greater impairment in functioning across all FAST domains than those in the remission phase (all differences, p < 0.01). Mean WHO-5 scores were 6.4 and 9.8 in the acute and remission phases, respectively (lower scores indicate poorer well-being). Overall, 65% of patients in the acute phase and 36% of those in remission reported that emotional blunting had a significant impact on their quality of life. Pearson correlation analysis showed a moderate positive correlation between ODQ and FAST total scores (r = 0.52) and a weak negative correlation between ODQ total score and WHO-5 score (r = - 0.26; both p < 0.01). In multivariate regression analysis, ODQ total score (in combination with other covariates) was the strongest significant predictor of poor patient functioning.

CONCLUSIONS

Emotional blunting has a substantial negative impact on patients' daily functioning, well-being, and quality of life in both the acute and remission phases of depression. These findings highlight the importance of recognizing and treating emotional blunting in patients with major depressive disorder in order to achieve full functional recovery.

Part I: clinical characteristics

BACKGROUND

Emotional blunting-inability to feel positive or negative emotions, detachment, or reduced emotional responsiveness-is common in people with depression. However, there is a paucity of studies comprehensively investigating this symptom and its functional impact. This study investigated the experience of emotional blunting, and its impact on overall functioning and quality of life, in the acute and remission phases of depression from the perspective of patients and healthcare providers. This paper presents data on the clinical presentation of emotional blunting in depression from the patient perspective.

METHODS

Cross-sectional, observational study conducted in Brazil, Canada, and Spain between April 15 and May 18, 2021. Data were collected via a self-completed online survey. Respondents were adults with depression (acute or remission phase), who were currently using a prescribed antidepressant, and who reported emotional blunting during the past 6 weeks. Emotional blunting was assessed using the Oxford Depression Questionnaire (ODQ; total score range 26-130, higher scores indicate greater emotional blunting).

RESULTS

In all, 752 patients completed the survey (62% female; mean age, 45 years). Overall, 44% of patients rated their emotional blunting as extremely severe (acute phase [n = 300], 72%; remission phase [n = 452], 25%; difference, p < 0.01). In all, 56% of patients considered their emotional blunting to be caused by their depression (acute phase, 62%; remission phase, 52%). Mean ODQ total score was 94.8 for patients in the acute phase of depression and 85.7 for those in remission (difference, p < 0.01). Mean score for the ODQ 'antidepressant as cause' domain (maximum possible score, 30) was 18.0 in patients in the acute phase and 17.6 in those in remission. Overall, 45% of patients believed that their antidepressant medication was blunting their emotions and 39% were considering stopping or had already stopped their antidepressant because of perceived emotion-related side effects.

CONCLUSIONS

Almost three-quarters of patients in the acute phase of depression and one-quarter of those in remission reported severe emotional blunting. Approximately 56% of patients considered their emotional blunting to be caused by their depression, while 45% believed that their antidepressant medication was negatively affecting their emotions. Just over one-third of patients were considering stopping or had stopped their antidepressant as a result.

Validation of the Oxford Depression Questionnaire: Sensitivity to change, minimal clinically important difference, and response threshold for the assessment of emotional blunting

BACKGROUND

The Oxford Depression Questionnaire (ODQ) is a patient-reported scale for assessing emotional blunting in patients with major depressive disorder (MDD). This analysis was undertaken to further validate the scale in patients experiencing emotional blunting while receiving antidepressant treatment.

METHODS

Patients with MDD who experienced inadequate depressive-symptom resolution and emotional blunting on selective serotonin reuptake inhibitor or serotonin-noradrenaline reuptake inhibitor monotherapy (adequate dose for ≥6 weeks) were switched to vortioxetine 10-20 mg/day. ODQ total scores were assessed excluding and including the "antidepressant-as-cause" domain (ODQ-20 and ODQ-26, respectively). Anchor- and distribution-based methods were used to determine the minimal clinically important difference in ODQ scores in terms of change from baseline to week 8 of antidepressant treatment.

RESULTS

After 8 weeks of vortioxetine treatment, the mean change in ODQ-20 and ODQ-26 scores from baseline was -24.8 and -30.1 points, respectively. Greater mean changes from baseline in ODQ-20 and ODQ-26 scores were seen in patients reporting no emotional blunting vs those still experiencing emotional blunting after 8 weeks of vortioxetine treatment (ODQ-20: -27.0 vs -22.6 points; ODQ-26: -32.8 vs -27.5 points, respectively). In patients considered clinically minimally improved (Clinical Global Impression-Improvement score, 3) after 8 weeks of vortioxetine treatment, respective mean (standard deviation) change in ODQ-20 and ODQ-26 score from baseline was -15.5 (18.1) and -20.0 (20.5) points.

LIMITATIONS

Short study duration.

CONCLUSIONS

These results provide further validation of the clinical utility of the ODQ for assessing emotional blunting in patients with MDD. The suggested minimal clinically important difference for change in ODQ-20 and ODQ-26 scores is 16 and 20 points, respectively, after 8 weeks of antidepressant treatment.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03835715.

Exploratory study of association between blood immune markers and cognitive symptom severity in major depressive disorder: Stratification by body mass index status

BACKGROUND

A subset of patients with Major Depressive Disorder (MDD) have shown differences relative to healthy controls in blood inflammatory and immune markers. Meanwhile, MDD and comorbid obesity appear to present with distinct biological and symptom characteristics, categorised as "atypical" or "immunometabolic" depression, although the relevant underlying biological mechanisms are still uncertain. Therefore, this exploratory study aimed to better characterise the relationship between peripheral blood immune markers and symptoms of MDD, as well as the extent to which body mass index (BMI) may alter this relationship.

METHODS

Linear regression analyses were performed between selected baseline characteristics including clinical scales and blood inflammatory markers in participants with MDD (n = 119) enrolled in the PREDDICT randomised controlled trial (RCT), using age, sex and BMI as covariates, and then stratified by BMI status. Specifically, the Montgomery-Åsberg Depression Rating Scale (MADRS) for symptom severity, Clinical Global Impression scale (CGI) for functional impairment, Oxford Depression Questionnaire (ODQ) for emotional blunting, and THINC integrated tool (THINC-it) for cognitive function were considered as clinical measures.

RESULTS

There was a significant association between basophil count and THINC-it Codebreaker mean response time (associated with complex attention, perceptual motor, executive function, and learning and memory abilities) in overweight individuals and with THINC-it Trails total response time (associated with executive function ability) in moderately obese individuals, when controlling for age, sex, and years of education. No correlation was found between any tested blood markers and MADRS, CGI or ODQ clinical measures, regardless of BMI.

DISCUSSION

Although the present study is exploratory, the results suggest that targeting of the immune system and of metabolic parameters might confer benefits, specifically in patients with high BMI and experiencing cognitive impairment associated with MDD.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN12617000527369p. Registered on 11 April 2017.

Emotional blunting with antidepressant treatments: A survey among depressed patients

BACKGROUND

Emotional blunting is regularly reported in depressed patients on antidepressant treatment but its actual frequency is poorly understood. We have previously used qualitative methods to develop an appropriate scale, the Oxford Questionnaire on the Emotional Side-Effects of Antidepressants (OQESA).

METHODS RESULTS

Six hundred and sixty nine depressed patients on treatment and 150 recovered (formerly depressed) controls (aged ≥18 years) participated in this internet-based survey. The rate of emotional blunting in treated depressed patients was 46%, slightly more frequent in men than women (52% versus 44%) and in those with higher Hospital Anxiety and Depression (HAD) scale scores. There was no difference according to antidepressant agent, though it appeared less frequent with bupropion. Depressed patients with emotional blunting had much higher total blunting scores on OQESA than controls (42.83 ± 14.73 versus 25.73 ± 15.00, p < 0.0001) and there was a correlation between total blunting score and HAD-Depression score (r = 0.521). Thus, those with HAD-D score >7 (n = 170) had a higher total questionnaire score, 49.23±12.03, than those with HAD-D score ≤7 (n = 140), 35.07 ± 13.98, and the difference between the two groups was highly significant. However, patients with HAD-D score ≤7 (n = 140) had a higher total score (35.07 ± 13.98) than the recovered controls (n = 150) (25.73 ± 15.00), and the difference between the two groups was significant. Among the patients with emotional blunting, 37% had a negative perception of their condition and 38% positive. Men reported a more negative perception than women (p=0.008), and patients with a negative perception were more likely to have higher HAD scores. Higher levels of emotional blunting are associated with a more negative perception of it by the patient (r = -0.423).

LIMITATIONS

Include self-evaluation and the modest size of the sample for detection of differences between antidepressants.

CONCLUSIONS

Emotional blunting is reported by nearly half of depressed patients on antidepressants. It appears to be common to all monoaminergic antidepressants. The OQESA scores are highly correlated with HAD depression score; emotional blunting cannot be described simply as a side-effect of antidepressants, but also as a symptom of depression. A higher degree of emotional blunting is associated with a poorer quality of remission. The OQESA scale allows the detection of this phenomenon.

Dimorphic changes of some features of loving relationships during long-term use of antidepressants in depressed outpatients

The present study aimed at investigating the possible changes of some features of loving relationships during long-term treatment of depression with both selective serotonin reuptake inhibitors (SSRIs) and tricyclics (TCAs), by means of a specifically designed test, the so-called "Sex, Attachment, Love" (SALT) questionnaire. The sample was composed by 192 outpatients (123 women and 69 men, mean age±SD: 41.2±10.2 years), suffering from mild or moderate depression, according to DSM-IV-TR criteria, that were selected if they were treated with one antidepressant only for at least six months and were involved in a loving relationship. The results showed that SSRIs had a significant impact on the feelings of love and attachment towards the partner especially in men, while women taking TCAs complained of more sexual side effects than men. These data were supported also by the detection of a significant interaction between drug and sex on the "Love" and "Sex" domains. The present findings, while demonstrating a dimorphic effect of antidepressants on some component of loving relationships, need to be deepened in future studies.