The biological face of melancholia: Are there any reliable biomarkers for this depression subtype?

Depression Severity, Slow- versus Fast-Wave Neural Activity, and Symptoms of Melancholia

Melancholia is a major and severe subtype of depression, with only limited data regarding its association with neurological phenomena. To extend the current understanding of how particular aspects of melancholia are correlated with brain activity, electroencephalographic data were collected from 100 adults (44 males and 56 females, all aged 18 y or more) and investigated for the association between symptoms of melancholia and the ratios of alpha/beta activity and theta/beta activity at parietal-occipital EEG sites PO1 and PO2. The results indicate differences in these associations according to the depressive status of participants and the particular symptom of melancholia. Depressed participants exhibited meaningfully direct correlations between alpha/beta and theta/beta activity and the feeling that "Others would be better off if I was dead" at PO1, whereas non-depressed participants had significant inverse correlations between theta/beta activity and "Feeling useless and not needed" and "I find it hard to make decisions" at PO1. The results are discussed in terms of the relative levels of fast-wave (beta) versus slow-wave (alpha, theta) activity exhibited by depressed and non-depressed participants in the parietal-occipital region and the cognitive activities that are relevant to that region.

Differentiating melancholic and non-melancholic depression via biological markers: A review

OBJECTIVES

Melancholia is a severe form of depression that is typified by greater genetic and biological influence, distinct symptomatology, and preferential response to physical treatment. This paper sought to broadly overview potential biomarkers of melancholia to benefit differential diagnosis, clinical responses and treatment outcomes. Given nuances in distinguishing melancholia as its own condition from other depressive disorder, we emphasised studies directly comparing melancholic to non-melancholic depression.

METHODS

A comprehensive literature search was conducted. Key studies were identified and summarised qualitatively.

RESULTS

105 studies in total were identified. These studies covered a wide variety of biomarkers, and largely fell into three domains: endocrinological (especially cortisol levels, particularly in response to the dexamethasone suppression test), neurological, and immunological (particularly inflammatory markers). Less extensive evidence also exists for metabolic, genetic, and cardiovascular markers.

CONCLUSIONS

Definitive conclusions were predominantly limited due to substantial heterogeneity in how included studies defined melancholia. Furthermore, this heterogeneity could be responsible for the between- and within-group variability observed in the candidate biomarkers that were examined. Therefore, clarifying these definitional parameters may help identify underlying patterns in biomarker expression to improve diagnostic and therapeutic precision for the depressive disorders.

Melancholic features and typical neurovegetative symptoms of major depressive disorder show specific polygenic patterns

BACKGROUND

Major depressive disorder (MDD) is a highly prevalent psychiatric condition characterised by a heterogeneous clinical presentation and an estimated twin-based heritability of ~40-50 %. Different clinical MDD subtypes might partly reflect distinctive underlying genetics. This study aims to investigate if polygenic risk scores (PRSs) for different psychiatric disorders, personality traits, and substance use-related traits may be associated with different clinical subtypes of MDD (i.e., MDD with melancholic or psychotic features), higher symptom severity, or different clusters of depressive symptoms (i.e., sadness symptoms, typical neurovegetative symptoms, detachment symptoms, and negative thoughts).

METHODS

The target sample included 1149 patients with MDD, recruited by the European Group for the Study of Resistant Depression. PRSs for 25 psychiatric disorders and traits were computed based on the most recent publicly available summary statistics of the largest genome-wide association studies. PRSs were then used as predictors in regression models, adjusting for age, sex, population stratification, and recruitment sites.

RESULTS

Patients with MDD having higher PRS for MDD and loneliness were more likely to exhibit melancholic features of MDD (p = 0.0009 and p = 0.005, respectively). Moreover, patients with higher PRS for alcohol intake and post-traumatic stress disorder were more likely to experience greater typical neurovegetative symptoms (p = 0.0012 and p = 0.0045, respectively).

LIMITATIONS

The proportion of phenotypic variance explained by the PRSs was limited.

CONCLUSIONS

This study suggests that melancholic features and typical neurovegetative symptoms of MDD may show distinctive underlying genetics. Our findings provide a new contribution to the understanding of the genetic heterogeneity of MDD.

FMRI study of implicit emotional face processing in patients with MDD with melancholic subtype

Introduction

The accurate perception of facial expressions plays a vital role in daily life, allowing us to select appropriate responses in social situations. Understanding the neuronal basis of altered emotional face processing in patients with major depressive disorder (MDD) may lead to the appropriate choice of individual interventions to help patients maintain social functioning during depressive episodes. Inconsistencies in neuroimaging studies of emotional face processing are caused by heterogeneity in neurovegetative symptoms of depressive subtypes. The aim of this study was to investigate brain activation differences during implicit perception of faces with negative and positive emotions between healthy participants and patients with melancholic subtype of MDD. The neurobiological correlates of sex differences of MDD patients were also examined.

Methods

Thirty patients diagnosed with MDD and 21 healthy volunteers were studied using fMRI while performing an emotional face perception task.

Results

Comparing general face activation irrespective of emotional content, the intensity of BOLD signal was significantly decreased in the left thalamus, right supramarginal gyrus, right and left superior frontal gyrus, right middle frontal gyrus, and left fusiform gyrus in patients with melancholic depression compared to healthy participants. We observed only limited mood-congruence in response to faces of differing emotional valence. Brain activation in the middle temporal gyrus was significantly increased in response to fearful faces in comparison to happy faces in MDD patients. Elevated activation was observed in the right cingulate for happy and fearful faces, in precuneus for happy faces, and left posterior cingulate cortex for all faces in depressed women compared to men. The Inventory for Depressive Symptomatology (IDS) score was inversely correlated with activation in the left subgenual gyrus/left rectal gyrus for sad, neutral, and fearful faces in women in the MDD group. Patients with melancholic features performed similarly to controls during implicit emotional processing but showed reduced activation.

Discussion and conclusion

This finding suggests that melancholic patients compensate for reduced brain activation when interpreting emotional content in order to perform similarly to controls. Overall, frontal hypoactivation in response to implicit emotional stimuli appeared to be the most robust feature of melancholic depression.

Prevalence of major depressive disorder in 51,658 otherwise healthy adult Danes: Sex differences in symptomatology and prediction of future anti-depressive medication

Major Depressive Disorder (MDD) is a heterogeneous disease, which displays sex differences in symptomatology. This study aimed to assess point prevalence of MDD in undiagnosed, healthy adults as well as sex differences in symptomatology and clarify if specific symptoms increased the later need for anti-depressive medication. The study included 51,658 blood donors. Depressive symptoms were assessed according to ICD-10 using the Major Depression Inventory. Demographics, previous MDD, anti-depressive medication were collected from questionnaires and population registers. Descriptive, Logistic and Cox regression analyses were conducted. In total, 1.15% participants met the criteria for MDD. Women were significantly more likely to experience "increased appetite" and less likely to experience "a feeling of life not worth living", compared to men. MDD significantly associated with an increased hazard of later receiving a prescription for anti-depressive medication. The risk increased proportionally with increasing MDD severity. The two symptoms, "feeling that life is not worth living" and "trouble sleeping" were the strongest individual predictive symptoms of future anti-depressive medication in women and men, respectively. The results confirm findings in MDD patient groups. The diagnostic and prognostic value should be investigated further to address their potential as part of the clinical assessment.

Gender differences in clinical and biochemical parameters of patients consecutively hospitalized for unipolar depression

Major Depressive Disorder (MDD) is a medical illness twice as common in women than in men lifetime. Purpose of this study is to identify gender differences in clinical and biochemical parameters in subjects affected by MDD to implement individualized treatment strategies. We recruited 234 patients (112 males and 122 females) consecutively hospitalized for MDD in Milan (Italy). Data were obtained through a screening of the clinical charts and blood analyses. Univariate analyses, binary logistic regressions and a final logistic regression model were performed. The final logistic regression model showed that female patients (compared to males) had lower plasmatic levels of hemoglobin (p = 0.020) and uric acid (p = 0.002), higher levels of cholesterol (p < 0.001), had been treated with a lower number of antidepressants (p = 0.011), presented lower red blood cells (p < 0.001) and showed more frequently comorbidity with hypothyroidism (p = 0.036). Univariate analyses identified also that women had an earlier age at onset (p = 0.043), were less likely to have comorbidity with diabetes (p = 0.002) and were less frequently treated with a psychiatric polytherapy (p < 0.001). Finally, female patients had achieved more frequently remission in the last depressive episode (p = 0.001) and were more likely to have family history for psychiatric disorders (p < 0.001) than males. Female patients globally have a better response to treatments, but they seem to be more vulnerable to specific metabolic abnormalities as showed by more frequent hypercholesterolemia and lower plasma levels of uric acid. These results have to be confirmed by further studies.

A Preliminary Randomized Controlled Trial of Different Treatment Regimens for Melancholic Depression

BACKGROUND

Fluoxetine, bupropion, cognitive behavioral therapy (CBT), and physical therapies (modified electroconvulsive treatment or repetitive transcranial magnetic stimulation) can be used to manage melancholic depression.

OBJECTIVE

To compare the efficacy and safety of various treatments in patients with melancholic depression.

METHODS

This was a preliminary multicenter randomized controlled trial that included patients with depression in their first or recurrent acute episode between September 2016 and June 2019, and randomized to fluoxetine, fluoxetine+CBT, fluoxetine+bupropion, and fluoxetine+bupropion+brain stimulation. The primary endpoint was the decrease in the 17-item Hamilton Depression Rating Scale (17-HDRS). The secondary endpoint included the scores from the Quick Inventory of Depressive Symptomatology (QIDS-SR), QOL-6, and safety. Adverse events (AEs) were monitored. The follow-ups were performed at the end of the 0th, 2nd, 4th, 6th, 8th, and 12th weeks of treatment.

RESULTS

Finally, 113 patients were included in the analyses: fluoxetine (n=37), fluoxetine+CBT (n=27), fluoxetine+bupropion (n=34), and fluoxetine+bupropion+brain stimulation (n=15). The 17-HDRS and QIDS-SR scores decreased in all four groups (all P<0.05). There were no differences in the 17-HDRS scores among the four groups at the end of treatment (P=0.779), except for fluoxetine alone showing a better response regarding self-consciousness than fluoxetine+bupropion. The QOL-6 scores increased in all four groups. The occurrence of AEs among the four groups showed no significant difference (P=0.053).

CONCLUSION

This preliminary trial suggests that all four interventions (fluoxetine, fluoxetine+CBT, fluoxetine+bupropion, and fluoxetine+bupropion+brain stimulation) achieved similar response and remission rates in patients with melancholic depression, but that fluoxetine had a better effect on self-consciousness than fluoxetine+bupropion. The safety profile was manageable.

Peripheral Markers of Depression

Major Depressive Disorder (MDD) is a leading cause of disability worldwide, creating a high medical and socioeconomic burden. There is a growing interest in the biological underpinnings of depression, which are reflected by altered levels of biological markers. Among others, enhanced inflammation has been reported in MDD, as reflected by increased concentrations of inflammatory markers-C-reactive protein, interleukin-6, tumor necrosis factor-α and soluble interleukin-2 receptor. Oxidative and nitrosative stress also plays a role in the pathophysiology of MDD. Notably, increased levels of lipid peroxidation markers are characteristic of MDD. Dysregulation of the stress axis, along with increased cortisol levels, have also been reported in MDD. Alterations in growth factors, with a significant decrease in brain-derived neurotrophic factor and an increase in fibroblast growth factor-2 and insulin-like growth factor-1 concentrations have also been found in MDD. Finally, kynurenine metabolites, increased glutamate and decreased total cholesterol also hold promise as reliable biomarkers for MDD. Research in the field of MDD biomarkers is hindered by insufficient understanding of MDD etiopathogenesis, substantial heterogeneity of the disorder, common co-morbidities and low specificity of biomarkers. The construction of biomarker panels and their evaluation with use of new technologies may have the potential to overcome the above mentioned obstacles.