Bright light therapy in pregnant women with major depressive disorder: study protocol for a randomized, double-blind, controlled clinical trial

Lights at night mediate depression-like behavioral and molecular phenotypes in a glucocorticoid-dependent manner in male rats

Nocturnal light pollution, an underappreciated mood manipulator, disturbs the circadian rhythms of individuals in modern society. Preclinical and clinical studies have suggested that exposure to lights at night (LANs) results in depression-like phenotypes. However, the mechanism underlying the action of LANs remains unclear. Therefore, this study explored the potential influence of LANs on depression-related brain regions by testing brain-derived neurotrophic factor (BDNF), synaptic transmission, and plasticity in male Sprague-Dawley rats. Depression-related behavioral tests, enzyme-linked immunosorbent assays, and intracellular and extracellular electrophysiological recordings were performed. Resultantly, rats exposed to either white or blue LAN for 5 or 21 days exhibited depression-like behaviors. Both white and blue LANs reduced BDNF expression in the medial prefrontal cortex (mPFC) and ventrolateral periaqueductal gray (vlPAG). Moreover, both lights at night (LANs) elevated the plasma corticosterone levels. Pharmacologically, the activation of glucocorticoid receptors mimics the LAN-mediated effects on depression-like behaviors and reduces BDNF levels, whereas the inhibition of glucocorticoid receptors blocks LAN-mediated behavioral and molecular actions. Electrophysiologically, both LANs attenuated the stimulation-response curve, increased the paired-pulse ratio, and decreased the frequency and amplitude of miniature excitatory postsynaptic currents in the vlPAG. In the mPFC, LANs attenuate long-term potentiation and long-term depression. Collectively, these results suggested that white and blue LANs disturbed BDNF expression, synaptic transmission, and plasticity in the vlPAG and mPFC in a glucocorticoid-dependent manner. The results of the present study provide a theoretical basis for understanding the effects of nocturnal light exposure on depression-like phenotypes.

Striking the Balance: Bipolar Disorder in the Perinatal Period

The authors reviewed the literature, published between 2018 and 2023, on treating bipolar disorder in the perinatal period in order to summarize current treatment perspectives. Mood episodes occur during pregnancy and there are high rates of both initial onset and recurrence in the postpartum period. Bipolar disorder itself is associated with higher risks of adverse pregnancy outcomes, including gestational hypertension, hemorrhage, cesarean delivery, and small for gestational age infants. A general principle of perinatal treatment includes maintaining psychiatric stability of the pregnant person while reducing medication exposure risk to the fetus. A variety of factors can compromise psychiatric stability, including rapid discontinuation of stabilizing medications, decreased efficacy due to physiologic changes of pregnancy, and exacerbation of underlying psychiatric illness. Psychosocial interventions include optimizing sleep, increasing support, and reducing stress. The American College of Obstetricians and Gynecologists recommends against discontinuing or withholding medications solely due to pregnancy or lactation status. Individualized treatment involves a discussion of the risks of undertreated bipolar disorder weighed against the risks of individual medication choice based on available evidence regarding congenital malformations, adverse neonatal and obstetrical events, and neurodevelopmental outcomes. Valproate is not a first-line treatment due to higher risks. Data are lacking on safety for many newer medications. The authors review current safety data regarding lithium, lamotrigine, and antipsychotics, which are the most commonly used treatments for managing bipolar disorder in the perinatal period. Due to physiologic changes during pregnancy, frequent therapeutic drug monitoring and dose adjustments are required.

Blue light at night produces stress-evoked heightened aggression by enhancing brain-derived neurotrophic factor in the basolateral amygdala

Light is an underappreciated mood manipulator. People are often exposed to electronic equipment, which results in nocturnal blue light exposure in modern society. Light pollution drastically shortens the night phase of the circadian rhythm. Preclinical and clinical studies have reported that nocturnal light exposure can influence mood, such as depressive-like phenotypes. However, the effects of blue light at night (BLAN) on other moods and how it alters mood remain unclear. Here, we explored the impact of BLAN on stress-provoked aggression in male Sprague‒Dawley rats, focusing on its influence on basolateral amygdala (BLA) activity. Resident-intruder tests, extracellular electrophysiological recordings, and enzyme-linked immunosorbent assays were performed. The results indicated that BLAN produces stress-induced heightened aggressive and anxiety-like phenotypes. Moreover, BLAN not only potentiates long-term potentiation and long-term depression in the BLA but also results in stress-induced elevation of brain-derived neurotrophic factor (BDNF), mature BDNF, and phosphorylation of tyrosine receptor kinase B expression in the BLA. Intra-BLA microinfusion of BDNF RNAi, BDNF neutralizing antibody, K252a, and rapamycin blocked stress-induced heightened aggressive behavior in BLAN rats. In addition, intra-BLA application of BDNF and 7,8-DHF caused stress-induced heightened aggressive behavior in naïve rats. Collectively, these results suggest that BLAN results in stress-evoked heightened aggressive phenotypes, which may work by enhancing BLA BDNF signaling and synaptic plasticity. This study reveals that nocturnal blue light exposure may have an impact on stress-provoked aggression. Moreover, this study provides novel insights into the BLA BDNF-dependent mechanism underlying the impact of the BLAN on mood.

Functional connectivity of brain networks with three monochromatic wavelengths: a pilot study using resting-state functional magnetic resonance imaging

Exposure to certain monochromatic wavelengths can affect non-visual brain regions. Growing research indicates that exposure to light can have a positive impact on health-related problems such as spring asthenia, circadian rhythm disruption, and even bipolar disorders and Alzheimer’s. However, the extent and location of changes in brain areas caused by exposure to monochromatic light remain largely unknown. This pilot study (N = 7) using resting-state functional magnetic resonance shows light-dependent functional connectivity patterns on brain networks. We demonstrated that 1 min of blue, green, or red light exposure modifies the functional connectivity (FC) of a broad range of visual and non-visual brain regions. Largely, we observed: (i) a global decrease in FC in all the networks but the salience network after blue light exposure, (ii) a global increase in FC after green light exposure, particularly noticeable in the left hemisphere, and (iii) a decrease in FC on attentional networks coupled with a FC increase in the default mode network after red light exposure. Each one of the FC patterns appears to be best arranged to perform better on tasks associated with specific cognitive domains. Results can be relevant for future research on the impact of light stimulation on brain function and in a variety of health disciplines.

Association between changes in the retina with major depressive disorder and sleep quality

BACKGROUND

Major depressive disorder (MDD) is linked to degenerative and inflammatory processes in the brain. The retina, as well as the brain, originates from the ectoderm. The changes in the retina that occur in concert with MDD and sleep quality are not very clear. This study aimed to detect changes in the retinal nerve fibre layer (RNFL) and macular thickness in Chinese patients in correlation with MDD and sleep quality.

METHODS

Thirty-six MDD patients and 187 age- and sex-matched healthy controls were enrolled in this study. All subjects were scanned by spectral-domain optical coherence tomography (OCT) and completed the Stroop Colour-Word Test (SCWT), Pittsburgh Sleep Quality Index, and Patient Health Questionnaire-9.

RESULTS

The RNFL and macular thickness were significantly thinner and disc-area enlargement of the right eye and cup-volume enlargement of both eyes were present in MDD patients. Linear regression analysis revealed that the RNFL and macular thickness in patients with MDD were correlated with sleep quality and the severity of depression. SCWT scores were higher following expansion of the cup volume of the right eye (all p < 0.01) and in correlation with larger disc areas.

CONCLUSIONS

Serious degrees of depression and insomnia in MDD patients may reflect obvious atrophy of the inner and outer rings of the right macula and enlargement of the optic disc in both eyes. These retinal structural changes might influence the visual cognition of patients with MDD.

Comparative Efficacy of Multiple Therapies for the Treatment of Patients With Subthreshold Depression: A Systematic Review and Network Meta-Analysis

Background: Subthreshold depression (SD) is considered to be the precursor stage of major depression, which is correlated with functional impairment and increased suicide rate. Although there are multiple therapies for the treatment of SD, the comparison and efficacy of various methods has yet to be evaluated. This study aimed to evaluate the efficacy of different therapies by performing a Bayesian network meta-analysis.

Methods: We searched eight databases on April 3, 2021. Center for Epidemiologic Studies Depression Scale (CES-D), Beck Depression Inventory scale (BDI), the Patient Health Questionnaire-9 (PHQ-9), and the Kessler Screening Scale for Psychological Distress (K-6) were used as efficacy outcomes. This Bayesian network meta-analysis used a fixed-effects model.

Findings: Twenty-one randomized controlled trials involving 5,048 participants were included in this study. The results suggested that electroacupuncture (MD −12.00, 95% CrI −15.00, −10.00), conventional acupuncture plus wheat-grain moxibustion (MD −9.70, 95% CrI −14.00, −5.30), and the Chinese traditional peripateticism pill plus group counseling (MD −9.00, 95% CrI −11.00, −6.70) had better efficacy than the control group (CG) in improving CES-D. For BDI outcome, bright light therapy (MD −9.70, 95% CrI −13.00, −6.00), behavioral activation program (MD −5.70, 95% CrI −6.10, −5.40), and dim light therapy (MD −6.30, 95% CrI −10.00, −2.20) were better than the CG. Tai chi (MD −3.00, 95% CrI −4.00, −2.00) was better than CG for PHQ-9 outcomes. Telephone-based cognitive behavioral treatment (MD −2.50 95% CrI −2.70, −2.30) was better than the CG for K-6 scores.

Conclusion: Our results suggest that electroacupuncture or bright light therapy appear to be the better choices in the treatment of SD. This study provide new insights into clinical treatment selection and may aid the development of guidelines for the management of SD.

Antidepressant treatment for postnatal depression

BACKGROUND

Depression is one of the most common morbidities of the postnatal period. It has been associated with adverse outcomes for women, children, the wider family and society as a whole. Treatment is with psychosocial interventions or antidepressant medication, or both. The aim of this review is to evaluate the effectiveness of different antidepressants and to compare their effectiveness with placebo, treatment as usual or other forms of treatment. This is an update of a review last published in 2014.

OBJECTIVES

To assess the effectiveness and safety of antidepressant drugs in comparison with any other treatment (psychological, psychosocial, or pharmacological), placebo, or treatment as usual for postnatal depression.

SEARCH METHODS

We searched Cochrane Common Mental Disorders's Specialized Register, CENTRAL, MEDLINE, Embase and PsycINFO in May 2020. We also searched international trials registries and contacted experts in the field.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of women with depression during the first 12 months postpartum that compared antidepressant treatment (alone or in combination with another treatment) with any other treatment, placebo or treatment as usual.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data from the study reports. We requested missing information from study authors wherever possible. We sought data to allow an intention-to-treat analysis. Where we identified sufficient comparable studies we pooled data and conducted random-effects meta-analyses.

MAIN RESULTS

We identified 11 RCTs (1016 women), the majority of which were from English-speaking, high-income countries; two were from middle-income countries. Women were recruited from a mix of community-based, primary care, maternity and outpatient settings. Most studies used selective serotonin reuptake inhibitors (SSRIs), with treatment duration ranging from 4 to 12 weeks. Meta-analysis showed that there may be a benefit of SSRIs over placebo in response (55% versus 43%; pooled risk ratio (RR) 1.27, 95% confidence interval (CI) 0.97 to 1.66); remission (42% versus 27%; RR 1.54, 95% CI 0.99 to 2.41); and reduced depressive symptoms (standardised mean difference (SMD) -0.30, 95% CI -0.55 to -0.05; 4 studies, 251 women), at 5 to 12 weeks' follow-up. We were unable to conduct meta-analysis for adverse events due to variation in the reporting of this between studies. There was no evidence of a difference between acceptability of SSRI and placebo (27% versus 27%; RR 1.10, 95% CI 0.74 to 1.64; 4 studies; 233 women). The certainty of all the evidence for SSRIs was low or very low due to the small number of included studies and a number of potential sources of bias, including high rates of attrition. There was insufficient evidence to assess the efficacy of SSRIs compared with other classes of antidepressants and of antidepressants compared with other pharmacological interventions, complementary medicines, psychological and psychosocial interventions or treatment as usual. A substantial proportion of women experienced adverse effects but there was no evidence of differences in the number of adverse effects between treatment groups in any of the studies. Data on effects on children, including breastfed infants, parenting, and the wider family were limited, although no adverse effects were noted.

AUTHORS' CONCLUSIONS

There remains limited evidence regarding the effectiveness and safety of antidepressants in the management of postnatal depression, particularly for those with more severe depression. We found low-certainty evidence that SSRI antidepressants may be more effective in treating postnatal depression than placebo as measured by response and remission rates. However, the low certainty of the evidence suggests that further research is very likely to have an important impact on our effect estimate. There is a continued imperative to better understand whether, and for whom, antidepressants or other treatments are more effective for postnatal depression, and whether some antidepressants are more effective or better tolerated than others. In clinical practice, the findings of this review need to be contextualised by the extensive broader literature on antidepressants in the general population and perinatal clinical guidance, to inform an individualised risk-benefit clinical decision. Future RCTs should focus on larger samples, longer follow-up, comparisons with alternative treatment modalities and inclusion of child and parenting outcomes.

Chronobiology and Chronotherapy in Depression: Current Knowledge and Chronotherapeutic Promises

Background:

Depression is a heavily prevalent mental disorder. Symptoms of depression extend beyond mood, cognition, and behavior to include a spectrum of somatic manifestations in all organic systems. Changes in sleep and neuroendocrine rhythms are especially prominent, and disruptions of circadian rhythms have been closely related to the neurobiology of depression. With the advent of increased research in chronobiology, various pathophysiologic mechanisms have been proposed, including anomalies of sleep architecture, the effects of clock gene polymorphisms in monoamine metabolism, and the deleterious impact of social zeitgebers. The identification of these chronodisruptions has propelled the emergence of several chronotherapeutic strategies, both pharmacological and non-pharmacological, with varying degrees of clinical evidence.

Methods:

The fundamental objective of this review is to integrate current knowledge about the role of chronobiology and depression and to summarize the interventions developed to resynchronize biorhythms both within an individual and with geophysical time.

Results:

We have found that among the non-pharmacological alternatives, triple chronotherapywhich encompasses bright light therapy, sleep deprivation therapy, and consecutive sleep phase advance therapy-has garnered the most considerable scientific interest. On the other hand, agomelatine appears to be the most promising pharmacological option, given its unique melatonergic pharmacodynamics.

Conclusions:

Research in chronotherapy as a treatment for depression is currently booming. Novel interventions could play a significant role in adopting new options for the treatment of depression, with Tripe Cronotherapy standing out as the most promising treatment.

Effects of bright light therapy for depression during pregnancy: a randomised, double-blind controlled trial

OBJECTIVES

Approximately 11%-13% of pregnant women suffer from depression. Bright light therapy (BLT) is a promising treatment, combining direct availability, sufficient efficacy, low costs and high safety for both mother and child. Here, we examined the effects of BLT on depression during pregnancy.

DESIGN

Randomised, double-blind controlled trial.

SETTING

Primary and secondary care in The Netherlands, from November 2016 to March 2019.

PARTICIPANTS

67 pregnant women (12-32 weeks gestational age) with a DSM-5 diagnosis of depressive disorder (Diagnostic and Statistical Manual of Mental Disorders).

INTERVENTIONS

Participants were randomly allocated to treatment with either BLT (9000 lux, 5000 K) or dim red light therapy (DRLT, 100 lux, 2700 K), which is considered placebo. For 6 weeks, both groups were treated daily at home for 30 min on awakening. Follow-up took place weekly during the intervention, after 6 weeks of therapy, 3 and 10 weeks after treatment and 2 months postpartum.

PRIMARY AND SECONDARY OUTCOME MEASURES

Depressive symptoms were measured primarily with the Structured Interview Guide for the Hamilton Depression Scale-Seasonal Affective Disorder. Secondary measures were the Hamilton Rating Scale for Depression and the Edinburgh Postnatal Depression Scale. Changes in rating scale scores of these questionnaires over time were analysed using generalised linear mixed models.

RESULTS

Median depression scores decreased by 40.6%-53.1% in the BLT group and by 50.9%-66.7% in the DRLT group. We found no statistically significant difference in symptom change scores between BLT and DRLT. Sensitivity and post-hoc analyses did not change our findings.

CONCLUSIONS

Depressive symptoms of pregnant women with depression improved in both treatment arms. More research is necessary to determine whether these responses represent true treatment effects, non-specific treatment responses, placebo effects or a combination hereof.

TRIAL REGISTRATION NUMBER

NTR5476.

A circadian rhythm-gated subcortical pathway for nighttime-light-induced depressive-like behaviors in mice

Besides generating vision, light modulates various physiological functions, including mood. While light therapy applied in the daytime is known to have anti-depressive properties, excessive light exposure at night has been reportedly associated with depressive symptoms. The neural mechanisms underlying this day-night difference in the effects of light are unknown. Using a light-at-night (LAN) paradigm in mice, we showed that LAN induced depressive-like behaviors without disturbing the circadian rhythm. This effect was mediated by a neural pathway from retinal melanopsin-expressing ganglion cells to the dorsal perihabenular nucleus (dpHb) to the nucleus accumbens (NAc). Importantly, the dpHb was gated by the circadian rhythm, being more excitable at night than during the day. This indicates that the ipRGC→dpHb→NAc pathway preferentially conducts light signals at night, thereby mediating LAN-induced depressive-like behaviors. These findings may be relevant when considering the mental health effects of the prevalent nighttime illumination in the industrial world.

A common clinical conundrum: Antidepressant treatment of depression in pregnant women

Depression during pregnancy is associated with adverse maternal, pregnancy, and infant outcomes. Treatment during pregnancy requires a balanced discussion of the risks of both drug exposure and untreated depression. An updated review of the epidemiology, outcomes, and management of maternal depression is presented. Adverse outcomes are associated with both maternal depression and antidepressants. Research gaps include data on the longitudinal developmental trajectory of offspring exposed to antidepressants compared to depression, with assessment of in utero symptom exposure and environmental exposures. Additionally, neonatal syndrome associated with antidepressant use during pregnancy has no consensus definition or mechanistic explanation. With sophisticated large-scale epidemiologic studies, there has been progress in distinguishing the impact of depression processes from medication used for treatment. Optimal treatment of perinatal depression includes close symptom monitoring and medication adjustments to maintain symptom remission. This evolving field requires frequent consultation with reproductive data sources included in this article.

Understanding Quantitative Circadian Regulations Are Crucial Towards Advancing Chronotherapy

Circadian rhythms have a deep impact on most aspects of physiology. In most organisms, especially mammals, the biological rhythms are maintained by the indigenous circadian clockwork around geophysical time (~24-h). These rhythms originate inside cells. Several core components are interconnected through transcriptional/translational feedback loops to generate molecular oscillations. They are tightly controlled over time. Also, they exert temporal controls over many fundamental physiological activities. This helps in coordinating the body’s internal time with the external environments. The mammalian circadian clockwork is composed of a hierarchy of oscillators, which play roles at molecular, cellular, and higher levels. The master oscillation has been found to be developed at the hypothalamic suprachiasmatic nucleus in the brain. It acts as the core pacemaker and drives the transmission of the oscillation signals. These signals are distributed across different peripheral tissues through humoral and neural connections. The synchronization among the master oscillator and tissue-specific oscillators offer overall temporal stability to mammals. Recent technological advancements help us to study the circadian rhythms at dynamic scale and systems level. Here, we outline the current understanding of circadian clockwork in terms of molecular mechanisms and interdisciplinary concepts. We have also focused on the importance of the integrative approach to decode several crucial intricacies. This review indicates the emergence of such a comprehensive approach. It will essentially accelerate the circadian research with more innovative strategies, such as developing evidence-based chronotherapeutics to restore de-synchronized circadian rhythms.

Treatment of Peripartum Bipolar Disorder

Bipolar disorder affects women throughout their childbearing years. During the perinatal period, women with bipolar disorder are vulnerable to depressive episode recurrences and have an increased risk for postpartum psychosis. Perinatal screening is critical to identify women at risk. Although medications are the mainstay of treatment, the choice of pharmacotherapy must be made by the patient based on a risk-benefit discussion with her physician. For optimal dosing in pregnancy, therapeutic drug monitoring may be required to maintain effective drug concentrations. Residual symptoms of bipolar depression are treatable with bright light therapy as an alternative to medication augmentation.

Is cognitive behavioral therapy a better choice for women with postnatal depression? A systematic review and meta-analysis

The present study evaluated the combined effectiveness of cognitive behavioral therapy (CBT) for postnatal depression. A systematic search was conducted across databases including PubMed, Embase, and the Cochrane library to identify the randomized controlled trials (RCTs) that assessing CBT versus control for postnatal depression until March 2017. Data was extracted by two reviewers, independently. The Review Manager 5.3 and Stata 11.0 were used to calculate the synthesized effect of CBT on depression, and anxiety. A total of 20 RCTs involving 3623 participants were included. The results of meta-analysis showed that CBT was associated with a better Edinburgh Postnatal Depression Scale (EPDS) than control in short-term (mean difference = -2.86, 95% CI: -4.41--1.31; P<0.05) and long-term (mean difference = -1.68, 95% CI: -1.81-1.56; P<0.05). CBT also improved short-term (mean difference = -6.30, 95% CI: -11.32--1.28; P<0.05) and long-term (mean difference = -4.31, 95% CI: -6.92--1.70; P<0.05) Beck Depression Inventory (BDI). Subgroup analysis based on intervention types showed that in-home and telephone-based therapy exhibited significant reductions in EPDS scores (P<0.05 for all). CBT significantly improved the short-term [odds ratio (OR) = 6.57, 95% CI: 1.84-23.48; P<0.05] and long-term (OR = 2.00, 95% CI: 1.61-2.48; P<0.05) depressive symptomatology as compared to control. CBT also reduced the score of Depression Anxiety Stress Scales (DASS), though without significance. In conclusion, CBT effectively improved the symptoms and progression of postnatal depression.

Seasonality of depressive symptoms during pregnancy

Various risk factors have been identified for antepartum depression. This study evaluated seasonal influences on antepartum depressive symptoms. Data of 2,438 pregnant women on current depressive symptoms was obtained from a large-scale cross-sectional study in The Netherlands. Most women were screened during the first trimester. Depressive symptoms were assessed using the Edinburgh Postnatal Depression Scale (EPDS) and dichotomized using ≥ 9 as cut-off score. The seasonal relationship between antepartum depressive symptoms and the month of assessment was estimated by fitting a sinusoidal curve to the data. A total of 323 women (13.2%) scored above cut-off. In the full sample, we found no significant evidence for seasonal influences on depressive symptoms after adjusting for confounders. Additionally, we found that the seasonal influence was obscured by the modification of the effect by current treatment status. In women untreated for psychiatric complaints, we found a minimum of depressive symptomatology in September and a maximum in March. In women treated for psychiatric complaints we found a minimum of depressive symptomatology in December and a maximum in June. Thus, the effects of seasonality are apparent, but opposite in treated and untreated women. However, health professionals should be aware of depressive symptoms the whole year through.

Light exposure via a head-mounted device suppresses melatonin and improves vigilant attention without affecting cortisol and comfort

We aimed at assessing whether a head-mounted light therapy device, enriched in blue wavelengths, suppresses melatonin secretion and improves vigilant attention in the late evening hours. We also assessed whether using such light device is associated with discomfort and physiological stress. Seventeen healthy young participants (eight females) participated in a counterbalanced within-subject design during which they were exposed for 2 hr before habitual sleep time to a blue-enriched light (1500 lx) or to a lower intensity red-light (150 lx) control condition, using a new-generation light emitting diode (LED) head-mounted device. Compared to the red light control condition, blue-enriched light significantly reduced melatonin secretion and reaction times during a psychomotor vigilance task while no significant differences were detected in discomfort and cortisol levels. These results suggest that, compared to a control condition, blue-enriched light, delivered by a new-generation head-mounted device, elicits typical non-visual responses to light without detectable discomfort and physiological stress. They suggest that such devices might constitute an effective alternative to standard light boxes.

Guidelines on treatment of perinatal depression with antidepressants: An international review

OBJECTIVE

Several countries have developed Clinical Practice Guidelines regarding treatment of perinatal depressive symptoms and perinatal use of antidepressant. We aimed to compare guidelines to guide clinicians in best clinical practice.

METHODS

An extensive search in guideline databases, MEDLINE and PsycINFO was performed. When no guidelines were (publicly) available online, we contacted psychiatric-, obstetric-, perinatal- and mood disorder societies of all first world countries and the five largest second world countries. Only Clinical Practice Guidelines adhering to quality criteria of the Appraisal of Guidelines for Research and Evaluation instrument and including a systematic review of evidence were included. Data extraction focussed on recommendations regarding continuation or withdrawal of antidepressants and preferred treatment in newly depressed patients.

RESULTS

Our initial search resulted in 1094 articles. After first screening, 40 full-text articles were screened. Of these, 24 were excluded for not being an official Clinical Practice Guidelines. In total, 16 Clinical Practice Guidelines were included originating from 12 countries. Eight guidelines were perinatal specific and eight were general guidelines.

CONCLUSION

During pregnancy, four guidelines advise to continue antidepressants, while there is a lack of evidence supporting this recommendation. Five guidelines do not specifically advise or discourage continuation. For new episodes, guidelines agree on psychotherapy (especially cognitive behavioural therapy) as initial treatment for mild to moderate depression and antidepressants for severe depression, with a preference for sertraline. Paroxetine is not preferred treatment for new episodes but switching antidepressants for ongoing treatment is discouraged (three guidelines). If mothers use antidepressants, observation of the neonate is generally recommended and breastfeeding encouraged.

Depressive disorders: Processes leading to neurogeneration and potential novel treatments

Mood disorders are wide spread with estimates that one in seven of the population are affected at some time in their life (Kessler et al., 2012). Many of those affected with severe depressive disorders have cognitive deficits which may progress to frank neurodegeneration. There are several peripheral markers shown by patients who have cognitive deficits that could represent causative factors and could potentially serve as guides to the prevention or even treatment of neurodegeneration. Circadian rhythm misalignment, immune dysfunction and oxidative stress are key pathologic processes implicated in neurodegeneration and cognitive dysfunction in depressive disorders. Novel treatments targeting these pathways may therefore potentially improve patient outcomes whereby the primary mechanism of action is outside of the monoaminergic system. Moreover, targeting immune dysfunction, oxidative stress and circadian rhythm misalignment (rather than primarily the monoaminergic system) may hold promise for truly disease modifying treatments that may prevent neurodegeneration rather than simply alleviating symptoms with no curative intent. Further research is required to more comprehensively understand the contributions of these pathways to the pathophysiology of depressive disorders to allow for disease modifying treatments to be discovered.