Bipolar and related disorders in DSM-5 and ICD-10

Clinical Markers of Physical Violence in Patients with Bipolar Disorder in Manic States

Purpose

Identifying patients with bipolar disorder (BD) in manic states (BD-M) who are at a high risk of physical violence is a matter of clinical concern. This retrospective institution-based study aimed to identify simple, rapid, and inexpensive clinical markers of physical violence in patients with BD-M.

Patients and Methods

The anonymized sociodemographic variables (sex, age, years of education, marital status) and clinical ones (weight, height, body mass index, blood pressure, the score of BRMS, number of BD episodes, psychotic symptoms, history of violence, biochemical parameters, and blood routine parameters) of 316 BD-M participants were collected, and the risk of physical violence was identified using the Brøset Violence Checklist (BVC). Difference tests, correlation analyses, and multivariate linear regression analysis were performed to identify clinical markers for the risk of physical violence.

Results

The participants were categorized into groups at low (49, 15.51%), medium (129, 40.82%), and high (138, 43.67%) risk of physical violence. The number of BD episodes, serum uric acid (UA), free thyroxine (FT4) levels, history of violence, and monocyte-to-lymphocyte ratio (MLR) differed significantly between groups (all P<0.05). The number of BD episodes (r=0.152), FT3 (r=0.131) and FT4 (r=0.132) levels, history of violence (r=0.206), and MLR (r=-0.132) were significantly correlated with the risk of physical violence (all P<0.05). The existence of history of violence, number of BD episodes, UA, FT4, and MLR were identified as clinical markers of the risk of physical violence in patients with BD-M (all P<0.05).

Conclusion

These identified markers are readily available at initial presentation and may help in the timely assessment and treatment of patients with BD-M.

The bipolar patients' family experiences of the outcomes of encountering stigma in Tehran: A qualitative study

INTRODUCTION

Nowadays, the most common psychological-social pressure to which bipolar patients' families are exposed is stigma. Therefore, the present study was conducted to delve into the bipolar patients' family experiences of the outcomes of encountering stigma.

METHOD

The study was of qualitative type. Purposive sampling was used to select the participants from the persons suffering from bipolar disorder and their families. Twenty seven of the participants were interviewed. The main data collection instrument was semi-structured interview with open questions. Additionally, the collected data were analyzed via inductive content analysis method. The accuracy and validity of the study rooted in four factors: credibility, transferability, verifiability, and reliability.

RESULTS

Data analysis led to 1,326 primary codes, which were further categorized into five main categories as the main outcomes of encountering stigma (social deprivation, emotional and sentimental excitement, objective and behavioral reflections, family solidarity threat, and separation from society) and 21 sub-categories.

CONCLUSION

Given then irreparable outcomes of stigma for bipolar patients' family, it is necessary to take it into consideration. It is recommended to use media and also hygienic-treatment centers to educate different levels of society as to appropriate treatment with these patients and their families.

Stigma in people living with bipolar disorder and their families: a systematic review

BACKGROUND

Stigma affects different life aspects in people living with bipolar disorder and their families. This study aimed to examining the experience of stigma and evaluating predictors, consequences and strategies to combat stigma in people with bipolar disorder and their families.

METHODS

We conducted a systematic review according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) in 2022. We extensively reviewed six online databases (PubMed, Scopus, Medline, EMBASE, Web of Science and Google Scholar). Articles published in the English language about stigma in people living with bipolar disorders and their families were included.

RESULTS

A total of 42,763 articles were retrieved, of which 40 articles from 14 countries were included in this study (n = 7417 participants). Of the 40 articles, 29 adopted quantitative methods (72.5%), two used mixed-methods (5%), eight used qualitative (20%) methods, and one was a case series (2.5%). The results of the studies were categorized into four themes: 1. Stigma experienced by people living with bipolar disorders and their families, 2. Predictors of stigma in people living with bipolar disorders and their families, 3. Consequences of stigma in people living with bipolar disorders and their families, 4. Effective interventions and strategies to reduce stigma in people living with bipolar disorders and their families.

CONCLUSION

The results of this study might be useful to design psychiatric cognitive interventions to reduce stigma in people living with bipolar disorders and their families and designing community-based interventions to normalize bipolar disorder at the community level.

The effectiveness of psychoeducation in improving attitudes towards psychological disorders and internalized stigma in the family members of bipolar patients: A quasi‐experimental study

Family members of bipolar patients experience stigma following being labeled by others, which can disrupt their routine lives and result in social isolation. This study aims to evaluate the effectiveness of psychoeducation in improving the attitudes of bipolar patients' family members towards psychological disorders and internalized stigma. The present study is a quasi-experimental study with a pre- and post-test follow-up design, in which 74 individuals were selected by convenience sampling among families who had a member with a bipolar disorder who was referred to the largest psychiatric hospital in Iran in 2021. The participants were randomly divided into the experimental and control groups (n = 37 per group). The members of the experimental group then underwent eight 90-min sessions of psychoeducation. The control group also received psychoeducation at the end of the study. The results of analysis of covariance showed that psychoeducation reduced internalized stigma in the family members of bipolar patients and increased their positive attitudes towards psychological disorders compared with the control group (p < .01). On this basis, psychoeducation can be useful to reduce the internalized stigma of family members of bipolar patients and to increase their positive attitudes towards psychological disorders.

Clinical and cortical similarities identified between bipolar disorder I and schizophrenia: A multivariate approach

BACKGROUND

Structural neuroimaging studies have identified similarities in the brains of individuals diagnosed with schizophrenia (SZ) and bipolar I disorder (BP), with overlap in regions of gray matter (GM) deficits between the two disorders. Recent studies have also shown that the symptom phenotypes associated with SZ and BP may allow for a more precise categorization than the current diagnostic criteria. In this study, we sought to identify GM alterations that were unique to each disorder and whether those alterations were also related to unique symptom profiles.

MATERIALS AND METHODS

We analyzed the GM patterns and clinical symptom presentations using independent component analysis (ICA), hierarchical clustering, and n-way biclustering in a large (N ∼ 3,000), merged dataset of neuroimaging data from healthy volunteers (HV), and individuals with either SZ or BP.

RESULTS

Component A showed a SZ and BP < HV GM pattern in the bilateral insula and cingulate gyrus. Component B showed a SZ and BP < HV GM pattern in the cerebellum and vermis. There were no significant differences between diagnostic groups in these components. Component C showed a SZ < HV and BP GM pattern bilaterally in the temporal poles. Hierarchical clustering of the PANSS scores and the ICA components did not yield new subgroups. N-way biclustering identified three unique subgroups of individuals within the sample that mapped onto different combinations of ICA components and symptom profiles categorized by the PANSS but no distinct diagnostic group differences.

CONCLUSION

These multivariate results show that diagnostic boundaries are not clearly related to structural differences or distinct symptom profiles. Our findings add support that (1) BP tend to have less severe symptom profiles when compared to SZ on the PANSS without a clear distinction, and (2) all the gray matter alterations follow the pattern of SZ < BP < HV without a clear distinction between SZ and BP.

Plasma oxysterols in drug-free patients with schizophrenia

Evidence from clinical, genetic, and medical studies has shown the neuronal developmental disorder aspect of schizophrenia (SZ). Whereas oxysterols are vital factors in neurodevelopment, it is still unknown whether they are involved in the pathophysiology of SZ. The current study aims to explore the profile of oxysterols in plasma, ratio to total cholesterol (Tchol) and the association with clinical factors in patients with SZ. Forty men diagnosed with SZ and forty healthy controls matched for age and sex were included in the study. The ratios of cholestane-3β,5α,6β-triol, 27-hydroxycholesterol (27-OHC) and Cholestanol to Tchol increased in the schizophrenic group compared to controls. However, levels of 24S-hydroxycholesterol (24-OHC) were not significantly different between patients and controls. For the SZ patients, the plasma 24-OHC levels were positively correlated with the positive and negative syndrome total scores (PANSS) but negatively correlated with the Montreal Cognitive Assessment scores (MOCA). Moreover, the ratio Cholestanol to Tchol was negatively correlated with MOCA scores and positively correlated with PANSS general. The binary logistic regression analysis revealed that the ratio Cholestane-3β,5α,6β-triol/TChol could be considered as an independent risk factor for SZ. On the other hand, the receiver's operating characteristics analysis corresponding to potential biomarkers on SZ showed Areas Under the Curve (AUCs) of 82.1%; 69.7% and 77.6% for the ratio of Cholestane-3β,5α,6β-triol/TChol, 27-OHC/TChol and Cholestanol/TChol respectively. The relevance of Cholestane-3β,5α,6β-triol, 27-OHC and Cholestanol assays as biomarkers of this disease deserves further investigation.

Medication Management of Neuropsychiatric Symptoms in Neurological Conditions: A Dimensional Transdiagnostic Approach

Neuropsychiatric symptoms are prevalent in neurologic practice, but their complexity makes them challenging to manage. Many cognitive, affective, behavioral, and perceptual symptoms span multiple neurologic diagnoses-and there is prominent variability in neuropsychiatric symptom burden for a given condition. There is also a relative lack of robust controlled clinical trial evidence and expert consensus recommendations for a range of neuropsychiatric symptom presentations. Thus, the categorical approach (e.g., a discrete diagnosis equals a specific set of medication interventions) used in many other medical conditions can sometimes have limited utility in commonly encountered neuropsychiatric clinical scenarios. In this review, we explore medication management for a range of neuropsychiatric symptoms using a dimensional transdiagnostic approach applied to the neurological patient. This approach allows the clinician to think beyond the boundaries of a discrete diagnosis and treat specific symptom domains (e.g., apathy, impulsivity). Pharmacologic considerations, including mechanisms of action and their application to various neurotransmitter systems and brain networks, are discussed, as well as general recommendations to optimize medication adherence and rapport with the patient. The dimensional, transdiagnostic approach to pharmacological management of patients with neurological conditions will help the clinician treat neuropsychiatric symptoms safely, effectively, and confidently.

Comparisons of disease cluster patterns, prevalence and health factors in the USA, Canada, England and Ireland

Background

Identification of those who are most at risk of developing specific patterns of disease across different populations is required for directing public health policy. Here, we contrast prevalence and patterns of cross-national disease incidence, co-occurrence and related risk factors across population samples from the U.S., Canada, England and Ireland.

Methods

Participants (n = 62,111) were drawn from the US Health and Retirement Study (n = 10,858); the Canadian Longitudinal Study on Ageing (n = 36,647); the English Longitudinal Study of Ageing (n = 7938) and The Irish Longitudinal Study on Ageing (n = 6668). Self-reported lifetime prevalence of 10 medical conditions, predominant clusters of multimorbidity and their specific risk factors were compared across countries using latent class analysis.

Results

The U.S. had significantly higher prevalence of multimorbid disease patterns and nearly all diseases when compared to the three other countries, even after adjusting for age, sex, BMI, income, employment status, education, alcohol consumption and smoking history. For the U.S. the most at-risk group were younger on average compared to Canada, England and Ireland. Socioeconomic gradients for specific disease combinations were more pronounced for the U.S., Canada and England than they were for Ireland. The rates of obesity trends over the last 50 years align with the prevalence of eight of the 10 diseases examined. While patterns of disease clusters and the risk factors related to each of the disease clusters were similar, the probabilities of the diseases within each cluster differed across countries.

Conclusions

This information can be used to better understand the complex nature of multimorbidity and identify appropriate prevention and management strategies for treating multimorbidity across countries.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-11706-8.

Estimation of Years Lived with Disability Using a Prevalence-Based Approach: Application to Major Psychiatric Disease in Korea

To help develop policies concerning the prevention of psychiatric disease in Korea, we reviewed the literature on this topic in different countries and used a prevalence-based approach to estimate the years lived with disability (YLDs) in Korean patients with major psychiatric diseases. We calculated YLDs by extracting data on the number of patients with mild, moderate, and severe cases of schizophrenia, bipolar disorder, and major depressive disorder, as classified by International Statistical Classification of Disease (ICD) codes. YLDs were highest for patients with major depressive disorder (1190.6; 73.9%), schizophrenia (303.3; 18.8%) and bipolar disorder (117.9; 7.3%). Men had higher YLDs for schizophrenia, 2502 (20-24 years); bipolar disorder, 477 (40-44 years); and major depressive disorder, 2034 (75-79 years). Women had higher YLDs for schizophrenia, 484 (45-49 years); bipolar disorder, 214 (≥80 years); and major depressive disorder, 3541 (75-79 years). The prevalence-based approach and severity distribution is useful for estimating long-term psychiatric disease burden and YLDs. However, YLD-estimation studies must compensate for the shortcomings of the ICD-10 by referencing the Diagnostic and Statistical Manual of Mental Disorders 5th edition, as well as updating the disability weight score according to disease severity.

Navigating the diagnostic challenges of bipolar disorder in youth

ABSTRACT

Bipolar disorder in youth is difficult to diagnose and treat, but early detection is important to mitigate risks and improve patient outcomes. This article evaluates the unique challenges of diagnosing and treating bipolar disorder in children and adolescents. Bipolar disorder is associated with a significant personal and societal health burden and frequently is misdiagnosed and incorrectly treated. More research is needed to understand the pathophysiology of bipolar disorder and which treatment options are best throughout the lifespan.

Plasma oxysterols: Altered level of plasma 24-hydroxycholesterol in patients with bipolar disorder

Cholesterol and its oxygenated metabolites, including oxysterols, are intensively investigated as potential players in the pathophysiology of brain disorders. Altered oxysterol levels have been described in patients with numerous neuropsychiatric disorders. Recent studies have shown that Bipolar disorder (BD) is associated with the disruption of cholesterol metabolism. The present study was aimed at investigating the profile of oxysterols in plasma, their ratio to total cholesterol and their association with clinical parameters in patients with BD. Thirty three men diagnosed with BD and forty healthy controls matched for age and sex were included in the study. Oxysterol levels were measured by isotope-dilution ultra-performance liquid chromatography-tandem mass spectrometry. Significantly higher levels were observed for cholestane-3β,5α,6β-triol, 27-hydroxycholesterol (27-OHC) and Cholestanol in patients with BD. The concentration of 24-hydroxycholesterol (24-OHC) was significantly lower in patients compared to controls. 24-OHC was also negatively correlated to MAS subscale score (r =-0.343; p = 0.049). In patients, 24-OHC was inversely correlated with age (r = -0.240; p = 0.045). Multivariate analysis found that BD acute decompensation was independently related to the rise in plasma 24-OHC (p = 0.002; OR = 0.966, 95 % CI [0.945 - 0.987]). However, the 24-OHC assay relevance as a biomarker of this disease deserves further investigation in other studies.

A machine learning algorithm to differentiate bipolar disorder from major depressive disorder using an online mental health questionnaire and blood biomarker data

The vast personal and economic burden of mood disorders is largely caused by their under- and misdiagnosis, which is associated with ineffective treatment and worsening of outcomes. Here, we aimed to develop a diagnostic algorithm, based on an online questionnaire and blood biomarker data, to reduce the misdiagnosis of bipolar disorder (BD) as major depressive disorder (MDD). Individuals with depressive symptoms (Patient Health Questionnaire-9 score ≥5) aged 18-45 years were recruited online. After completing a purpose-built online mental health questionnaire, eligible participants provided dried blood spot samples for biomarker analysis and underwent the World Health Organization World Mental Health Composite International Diagnostic Interview via telephone, to establish their mental health diagnosis. Extreme Gradient Boosting and nested cross-validation were used to train and validate diagnostic models differentiating BD from MDD in participants who self-reported a current MDD diagnosis. Mean test area under the receiver operating characteristic curve (AUROC) for separating participants with BD diagnosed as MDD (N = 126) from those with correct MDD diagnosis (N = 187) was 0.92 (95% CI: 0.86-0.97). Core predictors included elevated mood, grandiosity, talkativeness, recklessness and risky behaviour. Additional validation in participants with no previous mood disorder diagnosis showed AUROCs of 0.89 (0.86-0.91) and 0.90 (0.87-0.91) for separating newly diagnosed BD (N = 98) from MDD (N = 112) and subclinical low mood (N = 120), respectively. Validation in participants with a previous diagnosis of BD (N = 45) demonstrated sensitivity of 0.86 (0.57-0.96). The diagnostic algorithm accurately identified patients with BD in various clinical scenarios, and could help expedite accurate clinical diagnosis and treatment of BD.

Comorbidity of Coronavirus disease (COVID-19) and the first episode of bipolar disorder and its treatment challenges: A case report

This study attempted to diagnose and examine the treatment challenges of a 25-year-old patient with the first episode of bipolar I disorder (BD-I) who also had Coronavirus disease 2019 (COVID-19) at the same time. This patient was admitted to the general ward of the hospital, along with other COVID-19 patients, and was treated with electroconvulsive therapy (ECT). Our results showed that it is important to pay attention to the comorbidity of psychiatric disorders in patients with COVID-19 to evaluate and treat them completely and avoid drug interactions.

Clinical Picture, Temperament, and Personality of Patients with Mixed States

The construct of mixed states is a robust clinical entity with a high variability of prevalence according to different diagnostic criteria. Despite the changes over the years, current official diagnostic criteria still have poor clinical usefulness. Premorbid characteristics with a potential high clinical importance such as temperament, personality, and emotional reactivity are understudied in patients with mixed states and excluded from the current nosologic systems. The authors provide an overview of current nosography and clinical pictures of mixed states and discuss the role of temperament, personality, and emotional reactivity in mixed states.

Bipolar spectrum disorder: What evidence for pharmacological treatment? A systematic review

BACKGROUND AND OBJECTIVES

Bipolar spectrum disorder (BSD) is an extended concept of bipolar disorder (BD) that includes conditions that do not fulfill the criteria. There is no recommendation today about its treatment. We reviewed relevant literature focusing on pharmacological treatments, looking for high-strength evidence leading to guidelines.

METHODOLOGY

A literature search was conducted using MedLine / PubMed database and Google Scholar up to September 2018. Search words were related to BSD and pharmacological treatment.

RESULTS

The literature search yielded 621 articles. Out of these, 35 articles met our selection criteria. There was limited high quality data. Only one randomized control trial (RCT) and one randomized open label trial were found. Most studies used different definition of BSD.

CONCLUSIONS

There is a considerable lack of data and no evidence supporting efficacy of pharmacological treatment for BSD. There is a need for a consensus on the definition of BSD and more evidence studies to evaluate drug's effectiveness in this condition.

Bipolar Disorder Is Associated With an Increased Risk of Sexually Transmitted Infections: A Nationwide Population-based Cohort Study

BACKGROUND

Previous studies have suggested that sexually transmitted infections (STI) tend to increase in patients with bipolar disorder during a manic or hypomanic episode. However, in the long-term course of this disease, it is unclear whether patients with bipolar disorder have a higher risk of incident STI.

METHODS

Using the National Health Insurance Research Database of Taiwan, 3721 patients with bipolar disorder and 14,884 controls without bipolar disorder matched by gender and age were enrolled between 2000 and 2010 and followed up until the end of 2013. Participants who developed any STI (human immunodeficiency virus [HIV], syphilis, genital warts, gonorrhea, chlamydial infection, and trichomoniasis) during the follow-up period were identified. Cox regression analysis was performed to examine the risk of STI between patients with bipolar disorder and comparative controls.

RESULTS

Patients with bipolar disorder were prone to develop STI (hazard ratio [HR], 1.67, 95% confidence interval [95% CI], 1.27-2.18) especially for HIV (HR, 3.59; 95% CI, 1.16-11.08) and syphilis (HR, 2.26; 95% CI, 1.06-4.85). In addition, this study found that the incidence of STI was higher among women than men (HR, 1.83; 95% CI, 1.41-2.39).

CONCLUSIONS

This study shows that bipolar disorder is associated with an increased risk of developing STI, which has direct implications for the development of targeted prevention interventions or regular sexual health screening in mental health clinics to reduce the disproportionate burden of HIV and other STI in patients with bipolar disorder.

Peripheral blood lymphocyte subpopulations in patients with bipolar disorder type II

We investigated the phenotype of peripheral blood lymphocytes of patients with bipolar disorder type II in different phases of the disease in order to check whether there are specific changes in the immune parameters. Lymphocytes subpopulations were analyzed ex vivo with flow cytometry in patients in euthymic, depression or hypomanic phase of the disease and compared with healthy controls. All BD patients were characterized by lower percentage of CD3⁺CD4⁺ and CD3⁺CD8⁺ cells compared with healthy people. But only patients in depression and remission had higher percentage of B cells (CD19⁺ cells) compared with healthy people. The percentage of CD4⁺CD25⁺ and CD8⁺CD25⁺ cells was decreased in patients in hypomanic phase compared with healthy control. Patients in remission were characterized by increased concentrations of IL-6 and IL-10 and decreased level of TNF in blood serum. Significant correlations between immunologic parameters and the results of Hamilton or Young scale have also been found. Our results demonstrate that there are significant differences in lymphocyte subpopulations which depend on the phase of the disease the patient is currently in.

Progress in diagnosis and treatment of bipolar disorder among children and adolescents: an international perspective

Bipolar disorder (BPD) is a potentially lifelong condition characterised by extreme changes in mood that may begin in childhood and cause substantial impairment. Over the past decades, BPD has been the focus of increased attention mainly due to controversies surrounding its prevalence, diagnosis and treatment in children and adolescents. This report addresses these controversies by reviewing the extant evidence base, providing clinicians with a summary of the literature on diagnosis, phenomenology and treatment of paediatric BPD. The debate regarding diagnosing children with BPD based on severe irritability and aggression is mostly resolved. The current data support utilising the diagnostic criteria based on episodic changes of mood polarity. Therefore, longitudinal course of illness should be explored in detail when diagnosing BPD. Given high rates of genetic predisposition for BPD, assessment of youth should focus on obtaining accurate family history of this condition. Additionally, there has been a substantial increase in randomised placebo-controlled clinical trials evaluating pharmacological agents for mood stabilisation in children and adolescents, which we summarise in this review. Despite significant progress being made in the field of paediatric BPD, more research is needed in the areas of phenomenology, pathophysiology, course and treatment of this condition in youth.

Are rating scales for bipolar disorders fit for purpose?

The DSM-5 definition of bipolar disorder elevates increased activity or energy as a cardinal symptom (alongside mood changes) for mania and hypomania ('hypo/mania'). The ICD-10 likewise requires increases in activity and energy (alongside mood) for hypo/mania, as well as decreases for bipolar depression. Using bipolar disorder as an example, we propose that, when diagnostic criteria are revised, instruments used to measure clinical course and treatment response may need revisiting. Here, we highlight that the 'gold-standard' symptom rating scales for hypo/mania and depression were developed in an era when abnormalities of mood were viewed as the cardinal symptom of bipolar disorder. We contend that archetypal measures fail to give proportionate weighting to activity or energy, undermining their utility in monitoring bipolar disorder and treatment response in clinical and research practice.Declarations of interestJ.S. and G.M. are members of mMARCH, (Motor Activity Research Consortium for Health), which is led by Dr Kathleen Merikangas, National Institute for Mental Health. J.S. reports being a visiting professor at Diderot University, the Norwegian University of Science and Technology, Swinburne University of Technology and The University of Sydney; receiving grant funding from the UK Medical Research Council and from the UK Research for Patient Benefit programme; and receiving a personal fee from Janssen-Cilag for a non-promotional talk on sleep problems.

Proliferation and apoptosis of T lymphocytes in patients with bipolar disorder

The aim of the study was to evaluate proliferation capacity and susceptibility to apoptosis of T lymphocytes of patients with bipolar disorder (BD) and to investigate in vitro influence of two standard mood stabilizers: lithium and valproic acid on these parameters using flow cytometry. Our results show that T lymphocytes of BD patients, especially those treated with lithium, have reduced proliferation capacity compared to healthy people. In vitro studies showed that valproic acid reduces the number of cell divisions and percentages of proliferating cells regardless of health status but mainly in very high dose, while lithium has no significant influence on proliferation capacity of patients’ T lymphocytes. Lymphocytes of BD patients are also more prone to apoptosis compared with healthy individuals which is related to high expression of Bax, a pro-apoptotic protein. In vitro lithium protected patients’ lymphocytes from apoptosis proportionally to dose used. Valproic acid protected lymphocytes of patients from apoptosis mainly in therapeutic concentration. Our results show that mood stabilizers used to prevent relapses of the disease have anti-apoptotic effect on T lymphocytes of BD patients but they are not able to improve their proliferation capacity.

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.