Lithium has long been believed to reduce the risk of suicide and suicidal behaviour in people with mood disorders. Previous meta-analyses appeared to support this belief, but excluded relevant data due to the difficulty of conducting meta-analysis of rare events. The current study is an updated systematic review and meta-analysis that includes all eligible data, and evaluates suicide, non-fatal suicidal behaviour (including suicidal ideation) and suicide attempts.

We searched PubMed, PsycINFO and Embase and some trial registers. We included all randomised trials comparing lithium and placebo or treatment as usual in mood disorders published after 2000, to ensure suicide was reliably reported. Trial quality was assessed using the Cochrane Risk of Bias tool. Pooled data were analysed using Fisher's Exact test. In addition, meta-analysis was conducted using various methods, prioritizing the Exact method. All trials were included in the analysis of suicide initially, regardless of whether they reported on suicide or not. We conducted a sensitivity analysis with trials that specifically reported on suicides and one that included trials published before 2000. Pre-specified subgroup analyses were performed involving suicide prevention trials, trials excluding people already taking lithium, trials involving people with bipolar disorder exclusively and those involving people with mixed affective diagnoses. Non-fatal suicidal behaviour and suicide attempts were analysed using the same methods, but only trials that reported these outcomes were included. PROSPERO registration: CRD42021265809.

Twelve eligible studies involving 2578 participants were included. The pooled suicide rate was 0.2% for people randomised to lithium and 0.4% with placebo or treatment as usual, which was not a statistically significant difference; odds ratio (OR) = 0.41 (95% confidence interval 0.03–2.49), p = 0.45. Meta-analysis using the Exact method produced an OR of 0.42 (95% confidence interval 0.01–4.5). The result was not substantially different when restricted to 11 trials that explicitly reported suicides and remained statistically non-significant when including 15 trials published before 2000 (mostly in the 1970s). There were no significant differences in any subgroup analysis. There was no difference in rates of all non-fatal suicidal behaviour in seven trials that reported this outcome, or in five trials that reported suicide attempts specifically. Meta-analyses using other methods also revealed no statistically significant differences.

Evidence from randomised trials is inconclusive and does not support the idea that lithium prevents suicide or suicidal behaviour.

Compared to the general population, adoptees are more often referred to specialist psychiatric treatment, exhibit increased risk of suicide and display more symptoms of attention-deficit/hyperactivity-disorder. However, little is known about the impact of being an adoptee on the risk of developing an eating disorder. The aim of the present study was to assess whether international adoptees have a higher risk for eating disorders than native Swedes.

In the present retrospective cohort study, data from the Swedish total population registers on individuals born between 1979 and 2005 were used to assess whether international adoptees residing in Sweden (n = 25 287) have a higher risk for anorexia nervosa (AN) and other eating disorders (OED) than non-adoptees with Swedish-born parents from the general population (n = 2 046 835). The patterns of these results were compared to those for major depressive disorder (MDD), obsessive-compulsive disorder (OCD), and anxiety disorders to determine whether any observed effects were unique to eating disorders or reflected a more general impact on mental health outcomes.

A survival analysis adjusting for relevant demographic covariates revealed an elevated risk of all examined psychiatric disorders in international adoptees: hazard ratios (95% confidence intervals) are 1.21 (1.04–1.41) for AN, 1.60 (1.44–1.79) for OED, 1.90 (1.81–2.00) for MDD, 1.25 (1.09–1.44) for OCD, and 1.69 (1.60–1.78) for anxiety disorders.

Elevated risk of eating disorders as well as of MDD, OCD, and anxiety disorders was found in international adoptees. A parallel pattern between AN and OCD was observed, which both display less elevated rates than the other diagnoses. A considerable number of biological, environmental, and societal factors have been suggested to explain the observed differences in mental health between adoptees and non-adoptees, but they remain primarily theoretical.

Major depressive disorders are highly prevalent in the world population, contribute substantially to the global disease burden and cause high health care expenditures. Information on the economic impact of depression, as provided by cost-of-illness (COI) studies, can support policymakers in the decision-making regarding resource allocation. Although the literature on COI studies of depression has already been reviewed, there is no quantitative estimation of depression excess costs across studies yet. Our aims were to systematically review COI studies of depression with comparison group worldwide and to assess the excess costs of depression in adolescents, adults, elderly, and depression as a comorbidity of a primary somatic disease quantitatively in a meta-analysis.

We followed the PRISMA reporting guidelines. PubMed, PsycINFO, NHS EED, and EconLit were searched without limitations until 27/04/2018. English or German full-text peer-reviewed articles that compared mean costs of depressed and non-depressed study participants from a bottom-up approach were included. We only included studies reporting costs for major depressive disorders. Data were pooled using a random-effects model and heterogeneity was assessed with I2 statistic. The primary outcome was ratio of means (RoM) of costs of depressed v. non-depressed study participants, interpretable as the percentage change in mean costs between the groups.

We screened 12 760 articles by title/abstract, assessed 393 articles in full-text and included 48 articles. The included studies encompassed in total 55 898 depressed and 674 414 non-depressed study participants. Meta-analysis showed that depression was associated with higher direct costs in adolescents (RoM = 2.79 [1.69–4.59], p < 0.0001, I2 = 87%), in adults (RoM = 2.58 [2.01–3.31], p < 0.0001, I2 = 99%), in elderly (RoM = 1.73 [1.47–2.03], p < 0.0001, I2 = 73%) and in participants with comorbid depression (RoM = 1.39 [1.24–1.55], p < 0.0001, I2 = 42%). In addition, we conducted meta-analyses for inpatient, outpatient, medication and emergency costs and a cost category including all other direct cost categories. Meta-analysis of indirect costs showed that depression was associated with higher costs in adults (RoM = 2.28 [1.75–2.98], p < 0.0001, I2 = 74%).

This work is the first to provide a meta-analysis in a global systematic review of COI studies for depression. Depression was associated with higher costs in all age groups and as comorbidity. Pooled RoM was highest in adolescence and decreased with age. In the subgroup with depression as a comorbidity of a primary somatic disease, pooled RoM was lower as compared to the age subgroups. More evidence in COI studies for depression in adolescence and for indirect costs would be desirable.

For the past quarter of a century, Frank et al.’s (1991) consensus-based definitions of major depressive disorder (MDD) episode, remission, recovery, relapse and recurrence have been the paramount driving forces for consistency in MDD research as well as in clinical practice. This study aims to review the evidence for the empirical validation of Frank et al.’s proposed concept definitions and to discuss evidence-based modifications.

A literature search of Web of Science and PubMed from 1/1/1991 to 08/30/2017 identified all publications which referenced Frank et al.’s request for definition validation. Publications with data relevant for validation were included and checked for referencing other studies providing such data.

A total of 56 studies involving 39 315 subjects were included, mainly presenting data to validate the severity and duration thresholds for defining remission and recovery. Most studies indicated that the severity threshold for defining remission should decrease. Additionally, specific duration thresholds to separate remission from recovery did not add any predictive value to the notion that increased remission duration alleviates the risk of reoccurrence of depressive symptoms. Only limited data were available to validate the severity and duration criteria for defining a depressive episode.

Remission can best be defined as a less symptomatic state than previously assumed (Hamilton Rating Scale for Depression, 17-item version (HAMD-17) ⩽4 instead of ⩽7), without applying a duration criterion. Duration thresholds to separate remission from recovery are not meaningful. The minimal duration of depressive symptoms to define a depressive episode should be longer than 2 weeks, although further studies are required to recommend an exact duration threshold. These results are relevant for researchers and clinicians aiming to use evidence-based depression outcomes.

The aim of this systematic review of economic evaluations alongside randomised controlled trials (RCTs) was to provide a comprehensive overview of the evidence concerning cost-effectiveness analyses of common treatment options for major depression.

An existing database was used to identify studies reporting cost-effectiveness results from RCTs. This database has been developed by a systematic literature search in the bibliographic databases of PubMed, PsychINFO, Embase and Cochrane library from database inception to December 2014. We evaluated the quality of economic evaluations using a 10-item short version of the Drummond checklist. Results were synthesised narratively. The risk of bias of the included RCTs was assessed, based on the Cochrane risk of bias assessment tool.

Fourteen RCTs were included from the 5580 articles screened on titles and abstracts. The methodological quality of the health economic evaluations was relatively high and the majority of the included RCTs had low risk of bias in most of Cochrane items except blinding of participants and personnel. Cognitive behavioural therapy was examined in seven trials as part of a variety of treatment protocols and seems cost-effective compared with pharmacotherapy in the long-term. However cost-effectiveness results for the combination of psychotherapy with pharmacotherapy are conflicting and should be interpreted with caution due to limited comparability between the examined trials. For several treatments, only a single economic evaluation was reported as part of a clinical trial. This was the case for comparisons between different classes of antidepressants, for several types of psychotherapy (behavioural activation, occupational therapy, interpersonal psychotherapy, short-term psychotherapy, psychodynamic psychotherapy, rational emotive behavioural therapy, solution focused therapy), and for transcranial magnetic stimulation v. electroconvulsive therapy. The limited evidence base for these interventions means generalisations, based on economic evaluation alongside clinical trials, cannot easily be made.

There is some economic evidence underpinning many of the common treatment options for major depression. Wide variability was observed in study outcomes, probably attributable to differences in population, interventions or follow-up periods. For many interventions, only a single economic evaluation alongside clinical trials was identified. Thus, significant economic evidence gaps remain in the area of major depressive disorder.