Is depression one thing or many?

Cortisol and the Dexamethasone Suppression Test as a Biomarker for Melancholic Depression: A Narrative Review

The dexamethasone suppression test (DST) assesses the functionality of the HPA axis and can be regarded as the first potential biomarker in psychiatry. In 1981, a group of researchers at the University of Michigan published a groundbreaking paper regarding its use for diagnosing melancholic depression, reporting a diagnostic sensitivity of 67% and a specificity of 95%. While this study generated much enthusiasm and high expectations in the field of biological psychiatry, subsequent studies produced equivocal results, leading to the test being rejected by the American Psychiatric Association. The scientific reasons leading to the rise and fall of the DST are assessed in this review, suggestions are provided as to how the original test can be improved, and its potential applications in clinical psychiatry are discussed. An improved, standardized, and validated version of the DST would be a biologically meaningful and useful biomarker in psychiatry, providing a tool for clinicians caring for depressed patients in the areas of diagnosis, treatment, and prognosis, and predicting the risk of suicide. Additionally, such a test could be a crucial part in the generation of biologically homogenous patient cohorts, necessary for the successful development of new psychotropic medications.

Association between dietary patterns and depression: an umbrella review of meta-analyses of observational studies and intervention trials

CONTEXT

Depression is the most common causes of disease burden worldwide (GBD 2017 Disease and Injury Incidence and Prevalence Collaborators. Global, regional, and national incidence, prevalence, and years lived with disability for 354 diseases and injuries for 195 countries and territories, 1990-2017: a systematic analysis for the Global Burden of Disease Study 2017. Lancet. 2018;392:1789-1858).

OBJECTIVE

An umbrella review has been performed to assess the strength and validity of the available observational and trial evidence for the association between a variety of dietary patterns and depression.

DATA SOURCES

MEDLINE/PubMed, Scopus, Web of Science, EMBASE, PsycINFO, and Cochrane Database were searched.

DATA EXTRACTION

The Joanna Briggs Institute Umbrella Review Methodology was used.

DATA ANALYSIS

The review included 19 articles, covering a relatively wide range of dietary patterns: healthy dietary patterns (n = 8), Mediterranean diet (MedDiet) (n = 6), Dietary Inflammatory Index (DII) (n = 5), Western diet (n = 4), Dietary Approaches to Stop Hypertension (DASH) (n = 2), vegetarian diets (n = 4), and other dietary interventions (n = 2). The methodological quality of the included meta-analyses was generally low or critically low. The strength of the evidence was generally weak, although convincing or suggestive evidence was found for an inverse relationship between MedDiet/DII and depression. Higher adherence to the MedDiet and lower DII score were significantly associated with lower risk of depression.

CONCLUSION

Considering the generally high heterogeneity and low quality of the available evidence, further studies adopting more coherent and uniform methodologies are needed.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42020223376.

Screening for depression in primary care with Patient Health Questionnaire-9 (PHQ-9): A systematic review

BACKGROUND

Depression is a leading cause of disability. International guidelines recommend screening for depression and the Patient Health Questionnaire 9 (PHQ-9) has been identified as the most reliable screening tool. We reviewed the evidence for using it within the primary care setting.

METHODS

We retrieved studies from MEDLINE, Embase, PsycINFO, CINAHL and the Cochrane Library that carried out primary care-based depression screening using PHQ-9 in populations older than 12, from 1995 to 2018.

RESULTS

Forty-two studies were included in the systematic review. Most of the studies were cross-sectional (N=40, 95%), conducted in high-income countries (N=27, 71%) and recruited adult populations (N=38, 90%). The accuracy of the PHQ-9 was evaluated in 31 (74%) studies with a two-stage screening system, with structured interview most often carried out by primary care and mental health professionals. Most of the studies employed a cut-off score of 10 (N=24, 57%, total range 5 - 15). The overall sensitivity of PHQ-9 ranged from 0.37 to 0.98, specificity from 0.42 to 0.99, positive predictive value from 0.09 to 0.92, and negative predictive value from 0.8 to 1.

LIMITATIONS

Lack of longitudinal studies, small sample size, and the heterogeneity of primary-care settings limited the generalizability of our results.

CONCLUSIONS

PHQ-9 has been widely validated and is recommended in a two-stage screening process. Longitudinal studies are necessary to provide evidence of long-term screening effectiveness.

Red and Processed Meat Consumption and Risk of Depression: A Systematic Review and Meta-Analysis

Depression is one of the leading causes of disability worldwide, with more than 264 million people affected. On average, depression first appears during the late teens to mid-20s as result of a complex interaction of social, psychological and biological factors. The aim of this systematic review with meta-analysis is to assess the association between red and processed meat intake and depression (both incident and prevalent). This systematic review was conducted according to the methods recommended by the Cochrane Collaboration and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Relevant papers published through March 2020 were identified by searching the electronic databases MEDLINE, Embase and Scopus. All analyses were conducted using ProMeta3 software. A critical appraisal was conducted. Finally, 17 studies met the inclusion criteria. The overall effect size (ES) of depression for red and processed meat intake was 1.08 [(95% CI = 1.04; 1.12), p-value < 0.001], based on 241,738 participants. The results from our meta-analysis showed a significant association between red and processed meat intake and risk of depression. The presented synthesis will be useful for health professionals and policy makers to better consider the effect of diet on mental health status.

Who Consult an Adult Psychiatric Emergency Department? Pertinence of Admissions and Opportunities for Telepsychiatry

Background and Objectives: Psychiatric disorders constitute frequent causes of emergency department (ED) admissions and these rates are increasing. However, referring to ED a whole range of conditions that could or should be dealt with elsewhere is imposing itself as a problematic situation. We aimed: (1) to provide a descriptive picture of the socio-demographic and diagnostic characteristics of the visits among adults at the psychiatric ED; (2) to estimate the clinical pertinence of these visits. Materials and Methods: Retrospective analysis of diagnostic/socio-demographic characteristics and clinical trajectories of patients admitted for a psychiatric condition at the adult psychiatric ED of the University Hospital of Geneva (HUG), Switzerland, during a 6-week timespan. Results: In our sample (n = 763 total admissions for psychiatric conditions; n = 702 for inclusion of patients having received a medical evaluation), depression/anxiety, suicidal behavior (SB), psychotic episode, and substance use disorder (SUD), in descending order, were the most common diagnoses for referral. Patients belonged to younger age groups (≤65 years), had a familial status other than married/in couple, and did not present an unfavorable socio-demographic profile. Concerning the pertinence for a psychiatric ED, primary diagnosis of depression/anxiety is the only variable significantly associated with different grade of degree. By the examination of the patients’ trajectory from admission to discharge, the clinical pertinence for a psychiatric ED admission existed for cases assigned to the Echelle Suisse du Tri (EST^®) scale degree 1 (corresponding to most urgent and severe conditions), particularly for diagnoses of depression/anxiety associated with SB, SB as primary or comorbid diagnosis, and psychotic and manic/hypomanic episode. However, diagnoses of depression/anxiety without urgent and severe features (degrees 2, 3, 4) constituted the most frequent mode of presentation. Conclusions: Ambulatory and community-integrated settings could be more appropriate for the majority of patients admitted to adult psychiatric EDs. Moreover, the implementation of telepsychiatry strategies represents a very promising opportunity to offer these patients care continuity, reduce costs and filter the demand for psychiatric ED.

Depression and Objectively Measured Physical Activity: A Systematic Review and Meta-Analysis

Depression is a major contributor to the overall global burden of disease, with high prevalence and relapse rate. Several factors have been considered in order to reduce the depression burden. Among them, physical activity (PA) showed a potential protective role. However, evidence is contrasting probably because of the differences in PA measurement. The aim of this systematic review with meta-analysis is to assess the association between objectively measured PA and incident and prevalent depression. The systematic review was conducted according to methods recommended by the Cochrane Collaboration and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Relevant papers published through 31 August 2019 were identified searching through the electronic databases PubMed/MEDLINE, Excerpta Medica dataBASE (Embase), PsycINFO, Scopus, Web of Science (WoS), and the Cochrane Library. All analyses were conducted using ProMeta3. Finally, 42 studies met inclusion criteria. The overall Effect size (ES) of depression for the highest vs. the lowest level of PA was −1.16 [(95% CI = −1.41; −0.91), p-value < 0.001] based on 37,408 participants. The results of the meta-analysis showed a potential protective effect of PA on prevalent and incident depression.

Do the Trajectories of Bipolar Disorder and Schizophrenia Follow a Universal Staging Model?

OBJECTIVE

The purpose of this study is to address the question of whether a universal staging model of severe psychiatric disorders is a viable direction for future research by examining the extant literature.

METHOD

A narrative review was conducted of the relevant historical, conceptual, and empirical literature pertaining to the clinical trajectory of bipolar disorder and schizophrenia and issues relevant to staging.

RESULTS

There is substantive evidence that classic recurrent bipolar disorder is separable from schizophrenia on the basis of family history, developmental and clinical course, treatment response, and neurobiological findings. However, because of the intrinsic heterogeneity of diagnostic categories that has been amplified by recent changes in psychiatric taxonomy, key distinctions between the groups have become obfuscated. While mapping risk and illness markers to emerging psychopathology is a logical approach and may be of value for some psychiatric disorders and/or their clinical subtypes, robust evidence supporting identifiable stages per se is still lacking. Presently, even rudimentary stages such as prodromes cannot be meaningfully applied across different disorders and no commonalities can be found for the basis of universal staging.

CONCLUSIONS

Advances in the prediction of risk, accurate early illness detection, and tailored intervention will require mapping biomarkers and other risk indicators to reliable clinical phases of illness progression. Given the capricious nature of mood and psychotic disorders, this task is likely to yield success only if conducted in narrowly defined subgroups of individuals at high risk for specific illnesses. This approach is diametrically opposite to that being promulgated by proponents of a universal staging model.