Maintenance treatment and psychobiologic correlates of endogenous subtypes

Objective polysomnography-based sleep features and major depressive disorder subtypes in the general population

Insomnia and its opposite hypersomnia are part of the diagnostic criteria for major depressive disorder (MDD). However, no study has investigated whether the postulated sleep alterations in clinical subtypes of MDD are reflected in polysomnography (PSG)-derived objective sleep measures. The objective of this study was to establish associations between the melancholic, atypical and unspecified subtypes of MDD and objective PSG-based sleep features. This cross-sectional analysis included 1820 community-dwelling individuals who underwent PSG and a semi-structured psychiatric interview to elicit diagnostic criteria for MDD and its subtypes. Adjusted robust linear regression was used to assess associations between MDD subtypes and PSG-derived objective sleep measures. Current melancholic MDD was significantly associated with decreased absolute delta power and sleep efficiency and with increased wake after sleep onset. Remitted unspecified MDD was significantly associated with increased rapid eye movements density. No other significant associations were identified. Our findings reflect that some PSG-based sleep features differed in MDD subtypes compared with no MDD. The largest number of significant differences were observed for current melancholic MDD, whereas only rapid eye movements density could represent a risk factor for MDD as it was the only sleep measure that was also associated with MDD in remitted participants.

Electroencephalographic Parameters Differentiating Melancholic Depression, Non-melancholic Depression, and Healthy Controls. A Systematic Review

Introduction: The objective of this systematic review was to investigate whether electroencephalographic parameters can serve as a tool to distinguish between melancholic depression, non-melancholic depression, and healthy controls in adults. Methods: A systematic review comprising an extensive literature search conducted in PubMed, Embase, Google Scholar, and PsycINFO in August 2020 with monthly updates until November 1st, 2020. In addition, we performed a citation search and scanned reference lists. Clinical trials that performed an EEG-based examination on an adult patient group diagnosed with melancholic unipolar depression and compared with a control group of non-melancholic unipolar depression and/or healthy controls were eligible. Risk of bias was assessed by the Strengthening of Reporting of Observational Studies in Epidemiology (STROBE) checklist. Results: A total of 24 studies, all case-control design, met the inclusion criteria and could be divided into three subgroups: Resting state studies (n = 5), sleep EEG studies (n = 10), and event-related potentials (ERP) studies (n = 9). Within each subgroup, studies were characterized by marked variability on almost all levels, preventing pooling of data, and many studies were subject to weighty methodological problems. However, the main part of the studies identified one or several EEG parameters that differentiated the groups. Conclusions: Multiple EEG modalities showed an ability to distinguish melancholic patients from non-melancholic patients and/or healthy controls. The considerable heterogeneity across studies and the frequent methodological difficulties at the individual study level were the main limitations to this work. Also, the underlying premise of shifting diagnostic paradigms may have resulted in an inhomogeneous patient population. Systematic Review Registration: Registered in the PROSPERO registry on August 8th, 2020, registration number CRD42020197472.

Randomized comparison of selective serotonin reuptake inhibitor (escitalopram) monotherapy and antidepressant combination pharmacotherapy for major depressive disorder with melancholic features: a CO-MED report

BACKGROUND

The clinical effects of antidepressant combinations vs. monotherapy as initial treatment for major depression with melancholic features (MDD-MF) are unknown.

METHODS

Outpatients with chronic or recurrent major depression (MDD) were randomized to initial treatment with escitalopram+placebo (the MONO condition), bupropion-sustained release+escitalopram, or venlafaxine-extended release+mirtazapine (the COMB conditions) in the Combining Medications to Enhance Depression Outcomes (CO-MED) trial. Secondary data analyses were conducted to compare demographic and clinical characteristics, and contrast clinical responses according to drug treatment, in patients with MDD-MF (n=124) and non-melancholic MDD (n=481).

RESULTS

While numerically lower, remission rates in MDD-MF did not differ significantly from those with non-melancholic MDD either at 12 (33.1% vs. 41.0%, aOR 1.16, p=0.58) or 28 (39.5% vs. 46.8%, aOR=1.02, p=0.93) weeks of treatment. Remission rates did not differ significantly between combination and monotherapy groups in either MDD-MF or non-melancholic MDD patients at either time point. Similar conclusions were reached for response rates, premature study discontinuation, and self-rated depression symptom severity.

LIMITATIONS

This is a secondary analysis of data from the CO-MED trial, which was not designed to address differential treatment response in melancholic and non-melancholic MDD.

CONCLUSIONS

We found no evidence of differential remission or response rates to antidepressant combination or monotherapy between melancholic/non-melancholic MDD patients, or according to antidepressant treatment group, after 12 and 28 weeks. Melancholic features may not be a valid predictor of more favorable response to antidepressant combination therapy as initial treatment.

Insomnia in patients with depression: some pathophysiological and treatment considerations

The almost ubiquitous sleep disturbances in patients with depression commonly, but not always, subside with the remission of depression. Evidence linking insomnia with the risk of relapses in recurrent depression, as well as suicide, makes optimization of the treatment of insomnia associated with depression a priority. However, most antidepressant agents do not adequately address the sleep complaints in depression: their effects on sleep range from sizeable improvement to equally significant worsening. One approach to the management of insomnia associated with depression is to choose a sedating antidepressant agent such as trazodone, mirtazapine or agomelatine. A second approach is to start with a non-sedating antidepressant (e.g. the selective serotonin reuptake inhibitors, bupropion, venlafaxine or duloxetine); those with a persistent or treatment-emergent insomnia can be switched to a more sedating antidepressant, or offered a hypnotic or cognitive-behavioural therapy as adjunctive treatment. The review discusses the advantages and disadvantages of all treatment options, pharmacological and otherwise.

Psychosocial impairment and recurrence of major depression

Major depressive disorder is often marked by multiple recurrences. Unfortunately, it is difficult to predict specifically which patients will suffer a recurrence. This study examined whether psychosocial impairment is a risk factor for recurrence. A total of 290 subjects with unipolar major depressive disorder according to Research Diagnostic Criteria (RDC) were prospectively followed for up to 15 years as part of the Collaborative Depression Study (CDS), a multicenter longitudinal observational study of the mood disorders. Follow-up data on course of illness and psychosocial functioning were collected with the Longitudinal Interval Follow-up Evaluation (LIFE). The association of psychosocial impairment with recurrence of major depression was examined with mixed-effects logistic regression. The mean (SD) score for psychosocial functioning during recovery from an episode of major depression was 9.0 (2.7), with a possible range of 4 (no impairment) to 20 (severe impairment). For euthymic subjects who recovered from an episode of major depression, elevated psychosocial impairment was significantly associated with subsequent recurrence of major depression, with an odds ratio of 1.12 (95% confidence interval [CI], 1.06 to 1.19). The odds ratio of 1.12 indicates that for each 1-point increase in the functional impairment score, the risk of recurrence increases by about 12%. In patients who have recovered from an episode of major depression, the presence of psychosocial impairment may help identify who is at increased risk of recurrence.

Depression and sleep disorders: clinical relevance, economic burden and pharmacological treatment

A wide range of studies have been published over the past two decades that involve the intersection of sleep EEG, insomnia, psychiatric illness (especially depressive disorders) and psychopharmacology. Much of value has been discovered, but there have also been false starts and contradictory results. There is in fact strong evidence that insomnia is associated with medical and psychiatric illness and that the sleepiness associated with insomnia is the cause of many accidents. Thus, the direct (visits to doctors, cost of sleeping medication, complications from use of these medications) and indirect (accidents, quality of life) costs of insomnia are enormous and constitute a major public health problem in the industrialized countries. Believing that it is now timely to assess the state of this important research area, a consensus conference was convened on June 26-28, 1998, in Porto Cervo (Italy) to attempt to clarify the important issues and findings on the clinical effect of the different classes of antidepressant drugs on sleep quality in depression. The participants' consensus on some of the main topics is presented with the hope that this discussion and analysis will contribute to productive research in this important field.

The effects of antidepressants on sleep in patients with depression

This paper reviews sleep disturbances in patients with major depressive disorders and the effects of different classes of antidepressants on sleep. It is clear from the studies reviewed that not all antidepressants improve sleep, and, indeed, some worsen sleep disturbances in patients with depression. Whether sleep is improved or further disrupted is of high clinical significance, because persistent sleep problems elevate the risk of relapse, recurrence, or suicide, as well as the need for augmenting medications.