Major depressive disorder (MDD) is a common mood disorder, with a heritability of around 34%. Molecular genetic studies made significant progress and identified genetic markers associated with the risk of MDD; however, progress is slowed down by substantial heterogeneity as MDD is assessed differently across international cohorts. Here, we used a standardized online approach to measure MDD in multiple cohorts in the Netherlands and evaluated whether this approach can be used in epidemiological and genetic association studies of depression.

Within the Biobank Netherlands Internet Collaboration (BIONIC) project, we collected MDD data in eight cohorts involving 31 936 participants, using the online Lifetime Depression Assessment Self-report (LIDAS), and estimated the prevalence of current and lifetime MDD in 22 623 unrelated individuals. In a large Netherlands Twin Register (NTR) twin-family dataset (n ≈ 18 000), we estimated the heritability of MDD, and the prediction of MDD in a subset (n = 4782) through Polygenic Risk Score (PRS).

Estimates of current and lifetime MDD prevalence were 6.7% and 18.1%, respectively, in line with population estimates based on validated psychiatric interviews. In the NTR heritability estimates were 0.34/0.30 (s.e. = 0.02/0.02) for current/lifetime MDD, respectively, showing that the LIDAS gives similar heritability rates for MDD as reported in the literature. The PRS predicted risk of MDD (OR 1.23, 95% CI 1.15–1.32, R2 = 1.47%).

By assessing MDD status in the Netherlands using the LIDAS instrument, we were able to confirm previously reported MDD prevalence and heritability estimates, which suggests that this instrument can be used in epidemiological and genetic association studies of depression.

The neurodevelopmental and trauma theories are two widely cited models of psychosis. A third – the developmental risk factor model (DRFM) – recognises the combined role of neurodevelopmental risks and trauma. Our objective was to test these theories using preterm populations as a natural experiment, given the high prevalence of neurodevelopmental deficits and exposure to trauma.

Two population-based preterm birth cohorts, the Bavarian Longitudinal Study (BLS; N = 399) and EPICure Study (N = 184), were included with term-born controls. Peer victimisation in childhood was assessed by parent and child report and psychotic experiences (PE) were assessed in early adulthood. Different models of psychosis were tested using regression and mediation analyses.

There was support for the trauma and DRFM in the BLS. Peer victimisation increased the risk of PE for preterm and term-born participants equally [odds ratio = 4.87, 95% confidence interval (CI) 1.96–12.08]. There was an indirect effect where preterm children were more likely to be victimised, which subsequently increased risk of PE [β = 1.12 (s.e. = 0.61), 95% CI 0.11–2.48]. The results were replicated in EPICure.

Exposure to trauma which is experienced more often by neurodevelopmental risk children rather than neurodevelopmental risk per se increases the risk of PE. The findings are consistent with the trauma model and DRFM. Interventions focused on reducing trauma may reduce the development of PE.

Anorexia nervosa (AN) and bulimia nervosa (BN) are complex psychiatric conditions, in which both psychological and metabolic factors have been implicated. Critically, the experience of stress can precipitate loss-of-control eating in both conditions, suggesting an interplay between mental state and metabolic signaling. However, associations between psychological states, symptoms and metabolic processes in AN and BN have not been examined.

Eighty-five women (n = 22 AN binge/purge subtype, n = 33 BN, n = 30 controls) underwent remote salivary cortisol sampling and a 2-day, inpatient study session to examine the effect of stress on cortisol, gut hormones [acyl-ghrelin, peptide tyrosine tyrosine (PYY) and glucagon-like peptide-1] and food consumption. Participants were randomized to either an acute stress induction or control task on each day, and plasma hormones were serially measured before a naturalistic, ad libitum meal.

Cortisol-awakening response was augmented in AN but not in BN relative to controls, with body mass index explaining the most variance in post-awakening cortisol (36%). Acute stress increased acyl-ghrelin and PYY in AN compared to controls; however, stress did not alter gut hormone profiles in BN. Instead, a group-by-stress interaction showed nominally reduced cortisol reactivity in BN, but not in AN, compared to controls. Ad libitum consumption was lower in both patient groups and unaffected by stress.

Findings extend previous reports of metabolic dysfunction in binge-eating disorders, identifying unique associations across disorders and under stress. Moreover, we observed disrupted homeostatic signaling in AN following psychological stress, which may explain, in part, the maintenance of dysregulated eating in this serious illness.

Attention deficit hyperactivity disorder (ADHD) is highly heritable and is associated with lower educational attainment. ADHD is linked to family adversity, including hostile parenting. Questions remain regarding the role of genetic and environmental factors underlying processes through which ADHD symptoms develop and influence academic attainment.

This study employed a parent-offspring adoption design (N = 345) to examine the interplay between genetic susceptibility to child attention problems (birth mother ADHD symptoms) and adoptive parent (mother and father) hostility on child lower academic outcomes, via child ADHD symptoms. Questionnaires assessed birth mother ADHD symptoms, adoptive parent (mother and father) hostility to child, early child impulsivity/activation, and child ADHD symptoms. The Woodcock–Johnson test was used to examine child reading and math aptitude.

Building on a previous study (Harold et al., 2013, Journal of Child Psychology and Psychiatry, 54(10), 1038–1046), heritable influences were found: birth mother ADHD symptoms predicted child impulsivity/activation. In turn, child impulsivity/activation (4.5 years) evoked maternal and paternal hostility, which was associated with children's ADHD continuity (6 years). Both maternal and paternal hostility (4.5 years) contributed to impairments in math but not reading (7 years), via impacts on ADHD symptoms (6 years).

Findings highlight the importance of early child behavior dysregulation evoking parent hostility in both mothers and fathers, with maternal and paternal hostility contributing to the continuation of ADHD symptoms and lower levels of later math ability. Early interventions may be important for the promotion of child math skills in those with ADHD symptoms, especially where children have high levels of early behavior dysregulation.

Depression is a prevalent and impairing condition. Behavioral activation (BA) is a parsimonious, cost-effective, and easily disseminated psychological intervention for depression. The current meta-analysis expands on the existing literature supporting the efficacy of BA for depression by examining the effects of BA on additional relevant outcomes for patients with depression, namely the reduction in anxiety symptoms and increase in activation.

Randomized controlled trials of BA for depression compared to active and inactive control were identified via a systematic review. Effect sizes using Hedges's g were calculated for each outcome compared to both active and inactive control using random effects models. Subgroup analyses were used to examine the inclusion of a discussion of values as a moderator of depression symptom outcome in BA.

Twenty-eight studies were included. Meta-analyses of symptom change between groups from baseline-to-post intervention indicated that BA outperformed inactive control conditions for improvements in depression (g = 0.83), anxiety (g = 0.37), and activation (g = 0.64). The difference between BA and active control conditions was not significant for improvements in depression (g = 0.15), anxiety (g = 0.03), and activation (g = 0.04). There was no evidence for a discussion of values augmenting BA efficacy. Study quality was generally low, and there was evidence of publication bias.

In addition to improving depression, BA shows efficacy for reducing symptoms of anxiety and increasing activation. BA may not offer better outcomes relative to other active interventions. There is room for improvement in the quality of research in this area.

Experience of emotion is closely linked to valuation. Mood can be viewed as a bias to experience positive or negative emotions and abnormally biased subjective reward valuation and cognitions are core characteristics of major depression.

Thirty-four unmedicated subjects with major depressive disorder and controls estimated the probability that fractal stimuli were associated with reward, based on passive observations, so they could subsequently choose the higher of either their estimated fractal value or an explicitly presented reward probability. Using model-based functional magnetic resonance imaging, we estimated each subject's internal value estimation, with psychophysiological interaction analysis used to examine event-related connectivity, testing hypotheses of abnormal reward valuation and cingulate connectivity in depression.

Reward value encoding in the hippocampus and rostral anterior cingulate was abnormal in depression. In addition, abnormal decision-making in depression was associated with increased anterior mid-cingulate activity and a signal in this region encoded the difference between the values of the two options. This localised decision-making and its impairment to the anterior mid-cingulate cortex (aMCC) consistent with theories of cognitive control. Notably, subjects with depression had significantly decreased event-related connectivity between the aMCC and rostral cingulate regions during decision-making, implying impaired communication between the neural substrates of expected value estimation and decision-making in depression.

Our findings support the theory that abnormal neural reward valuation plays a central role in major depressive disorder (MDD). To the extent that emotion reflects valuation, abnormal valuation could explain abnormal emotional experience in MDD, reflect a core pathophysiological process and be a target of treatment.

Sleep apnea is one of the most common sleep disorders and it is related to multiple negative health consequences. Previous studies have shown that sleep apnea is influenced by genetic factors. However, studies have not investigated the genetic and environmental influences of symptoms of sleep apnea in young adults. Furthermore, the underpinnings of the relationship between apnea symptoms and internalizing/externalizing problems are unknown. The objectives of this study were to estimate the magnitude of: (1) genetic and environmental influences on self-reported apnea symptoms; (2) the relationship between self-reported apnea symptoms and internalizing/externalizing traits; (3) genetic and environmental influences on the associations between self-reported apnea symptoms, internalizing behaviors and externalizing behaviors.

In a twin/sibling study, univariate and multivariate models were fitted to estimate both individual variance and sources of covariance between symptoms of sleep apnea and internalizing/externalizing behaviors.

Our results show that genetic influences account for 40% of the variance in sleep apnea symptoms. Moreover, there are modest associations between depression, anxiety and externalizing behaviors with apnea symptoms (ranging from r = 0.22–0.29). However, the origins of these associations differ. For example, whereas most of the covariation between symptoms of depression and sleep apnea can be explained by genes (95%), there was a larger role for the environment (53%) in the association between symptoms of anxiety and sleep apnea.

Genetic factors explain a significant proportion of variance in symptoms of apnea and most of the covariance with depression.

First episode psychosis (FEP) patients who use cannabis experience more frequent psychotic and euphoric intoxication experiences compared to controls. It is not clear whether this is consequent to patients being more vulnerable to the effects of cannabis use or to their heavier pattern of use. We aimed to determine whether extent of use predicted psychotic-like and euphoric intoxication experiences in patients and controls and whether this differs between groups.

We analysed data on patients who had ever used cannabis (n = 655) and controls who had ever used cannabis (n = 654) across 15 sites from six countries in the EU-GEI study (2010–2015). We used multiple regression to model predictors of cannabis-induced experiences and to determine if there was an interaction between caseness and extent of use.

Caseness, frequency of cannabis use and money spent on cannabis predicted psychotic-like and euphoric experiences (p ⩽ 0.001). For psychotic-like experiences (PEs) there was a significant interaction for caseness × frequency of use (p < 0.001) and caseness × money spent on cannabis (p = 0.001) such that FEP patients had increased experiences at increased levels of use compared to controls. There was no significant interaction for euphoric experiences (p > 0.5).

FEP patients are particularly sensitive to increased psychotic-like, but not euphoric experiences, at higher levels of cannabis use compared to controls. This suggests a specific psychotomimetic response in FEP patients related to heavy cannabis use. Clinicians should enquire regarding cannabis related PEs and advise that lower levels of cannabis use are associated with less frequent PEs.

Postpartum psychosis (PP) is a severe postpartum disorder. While working memory and emotional processing-related brain function are consistently impaired in psychoses unrelated to the puerperium, no studies have investigated them in PP.

Twenty-four women at risk of developing PP (11 developed an episode – PE; 13 remained well – NPE) and 20 healthy postpartum women completed two functional magnetic resonance imaging tasks within a year of delivery: working memory (n-back) and emotional face recognition (fearful faces). We compared women at-risk of PP to controls, as well as NPE, PE, and controls to test for potential effects of a PP episode occurrence.

Women at-risk of PP and PE showed hyperactivation of lateral visual areas, precuneus, and posterior cingulate during the n-back task. The at-risk group as a whole, as well as the PE and NPE groups, showed hyperconnectivity of the right dorsolateral prefrontal cortex (DLPFC) with various parieto-occipito-temporo-cerebellar regions compared to controls during several n-back conditions. Increases in connectivity between the right DLPFC and ipsilateral middle temporal gyrus were observed in the PE group compared to NPE during 2-back. During the fearful faces task, at-risk women as a group showed hyperactivation of fronto-cingulo-subcortical regions, and hypoconnectivity between the left amygdala and ipsilateral occipito-parietal regions compared to controls. No significant performance differences were observed.

These results present preliminary evidence of a differential nature of functional brain abnormalities in PP compared to the typically observed reduced connectivity with the DLPFC in psychoses unrelated to puerperium, such as bipolar disorder.

An increase in reported psychological distress, particularly among adolescent girls, is observed across a range of countries. Whether a similar trend exists among students in higher education remains unknown. The aim of the current study was to describe trends in self-reported psychological distress among Norwegian college and university students from 2010 to 2018.

We employed data from the Students' Health and Wellbeing Study (SHoT), a nationwide survey for higher education in Norway including full-time students aged 18–34. Numbers of participants (participation rates) were n = 6065 (23%) in 2010, n = 13 663 (29%) in 2014 and n = 49 321 (31%) in 2018. Psychological distress was measured using the Hopkins Symptom Checklist-25 (HSCL-25).

Overall, a statistically significant increase in self-reported psychological distress was observed over time across gender and age-groups. HSCL-25 scores were markedly higher for women than for men at all time-points. Effect-size of the mean change was also stronger for women (time-by-gender interaction: χ2 = 70.02, df = 2, p < 0.001): in women, mean HSCL-25 score increased from 1.62 in 2010 to 1.82 in 2018, yielding a mean change effect-size of 0.40. The corresponding change in men was from 1.42 in 2010 to 1.53 in 2018, giving an effect-size of 0.26.

Both the level and increase in self-reported psychological distress among Norwegian students in higher education are potentially worrying. Several mechanisms may contribute to the observed trend, including changes in response style and actual increase in distress. The relative low response rates in SHoT warrant caution when interpreting and generalising the findings.

Cross-national studies have found, unexpectedly, that mental disorder prevalence is higher in high-income relative to low-income countries, but few rigorous studies have been conducted in very low-income countries. This study assessed mental disorders in Nepal, employing unique methodological features designed to maximize disorder detection and reporting.

In 2016–2018, 10714 respondents aged 15–59 were interviewed as part of an ongoing panel study, with a response rate of 93%. The World Mental Health version of the Composite International Diagnostic Interview (WMH-CIDI 3.0) measured lifetime and 12-month prevalence of selected anxiety, mood, alcohol use, and impulse control disorders. Lifetime recall was enhanced using a life history calendar.

Lifetime prevalence ranged from 0.3% (95% CI 0.2–0.4) for bipolar disorder to 15.1% (95% CI 14.4–15.7) for major depressive disorder. The 12-month prevalences were low, ranging from 0.2% for panic disorder (95% CI 0.1–0.3) and bipolar disorder (95% CI 0.1–0.2) to 2.7% for depression (95% CI 2.4–3.0). Lifetime disorders were higher among those with less education and in the low-caste ethnic group. Gender differences were pronounced.

Although cultural effects on reporting cannot be ruled out, these low 12-month prevalences are consistent with reduced prevalence of mental disorders in other low-income countries. Identification of sociocultural factors that mediate the lower prevalence of mental disorders in low-income, non-Westernized settings may have implications for understanding disorder etiology and for clinical or policy interventions aimed at facilitating resilience.

Psychological resilience – positive psychological adaptation in the context of adversity – is defined and measured in multiple ways across disciplines. However, little is known about whether definitions capture the same underlying construct and/or share similar correlates. This study examined the congruence of different resilience measures and associations with sociodemographic factors and body mass index (BMI), a key health indicator.

In a cross-sectional sample of 1429 African American adults exposed to child maltreatment, we derived four resilience measures: a self-report scale assessing resiliency (perceived trait resilience); a binary variable defining resilience as low depression and posttraumatic stress (absence of distress); a binary variable defining resilience as low distress and high positive affect (absence of distress plus positive functioning); and a continuous variable reflecting individuals' deviation from distress levels predicted by maltreatment severity (relative resilience). Associations between resilience measures, sociodemographic factors, and BMI were assessed using correlations and regressions.

Resilience measures were weakly-to-moderately correlated (0.27–0.69), though similarly patterned across sociodemographic factors. Women showed higher relative resilience, but lower perceived trait resilience than men. Only measures incorporating positive affect or resiliency perceptions were associated with BMI: individuals classified as resilient by absence of distress plus positive functioning had lower BMI than non-resilient (β = −2.10, p = 0.026), as did those with higher perceived trait resilience (β = −0.63, p = 0.046).

Relatively low congruence between resilience measures suggests studies will yield divergent findings about predictors, prevalence, and consequences of resilience. Efforts to clearly define resilience are needed to better understand resilience and inform intervention and prevention efforts.

The trajectories of psychological distress differ between individuals, but these differences can be difficult to understand because the measures contain both consistent and situational features; however, in longitudinal studies these sources of information can be disentangled. In addition to occasion-specific features, interindividual differences can be decomposed into two sources of information: trait and carry-over effects between neighboring occasions that are not related to the trait (i.e. accumulated situational effects).

To disentangle these three sources of variance throughout adulthood, the consistency (trait and accumulated situational effects) and occasion specificity of nine indicators of psychological distress from the Malaise Inventory were examined in two birth cohorts, the 1958 National Child Development Study (NCDS58), and the 1970 British Cohort Study (BCS70).

The scale was administered at ages 23, 33, 42, and 50 in NCDS58 (n = 7147), and at ages 26, 30, 34, and 42 in BCS70 (n = 6859). For each psychological symptom, more variance was consistent than occasion-specific. The majority of the consistency was due to trait variance as opposed to accumulated situational effects, indicating that an individual predisposed to be distressed at the beginning of the study remained more likely to be distressed over the whole period. Symptoms of rage were notably more consistent among males than females in both cohorts (78.1% and 81.3% variance explained by trait in NCDS58 and BCS70, respectively), and among females in the NCDS58 (69%).

Symptoms of psychological distress exhibited high stability throughout adulthood, especially among men, due mostly to interindividual trait differences.

This report tests the association of self-reported symptoms of irritability with overt behavior of anger attacks (uncharacteristic sudden bouts of anger that are disproportionate to situation and associated with autonomic activation).

Participants of the Establishing Moderators and Biosignatures of Antidepressant Response in Clinical Care study who completed Massachusetts General Hospital Anger Attacks questionnaire were included (n = 293). At each visit, the 17-item Hamilton Depression Rating Scale and the 16-item Concise Associated Symptom Tracking scale were used to measure depression, anxiety, and irritability. In those with anger attacks present v. those without anger attacks, separate t tests and mixed model analyses compared afore-mentioned symptoms at baseline and changes with treatment respectively. As anger attacks may occur without aggressive behaviors, analyses were repeated based only on the presence of aggressive behaviors.

At baseline, those with anger attacks (n = 109) v. those without anger attacks (n = 184) had similar levels of depression but higher levels of irritability [effect size (d) = 0.80] and anxiety (d = 0.32). With acute-phase treatment, participants with anger attacks experienced a greater reduction in irritability (p < 0.001) but not in depression (p = 0.813) or anxiety (p = 0.771) as compared to those without anger attacks. Yet, irritability levels at week-8 were higher in those with anger attacks (d = 0.32) than those without anger attacks. Similar results were found in participants with aggressive behaviors.

The presence of anger attacks in outpatients with major depressive disorder may identify a sub-group of patients with persistently elevated irritability.

Early detection and intervention strategies in patients at clinical high-risk (CHR) for syndromal psychosis have the potential to contain the morbidity of schizophrenia and similar conditions. However, research criteria that have relied on severity and number of positive symptoms are limited in their specificity and risk high false-positive rates. Our objective was to examine the degree to which measures of recency of onset or intensification of positive symptoms [a.k.a., new or worsening (NOW) symptoms] contribute to predictive capacity.

We recruited 109 help-seeking individuals whose symptoms met criteria for the Progression Subtype of the Attenuated Positive Symptom Psychosis-Risk Syndrome defined by the Structured Interview for Psychosis-Risk Syndromes and followed every three months for two years or onset of syndromal psychosis.

Forty-one (40.6%) of 101 participants meeting CHR criteria developed a syndromal psychotic disorder [mostly (80.5%) schizophrenia] with half converting within 142 days (interquartile range: 69–410 days). Patients with more NOW symptoms were more likely to convert (converters: 3.63 ± 0.89; non-converters: 2.90 ± 1.27; p = 0.001). Patients with stable attenuated positive symptoms were less likely to convert than those with NOW symptoms. New, but not worsening, symptoms, in isolation, also predicted conversion.

Results suggest that the severity and number of attenuated positive symptoms are less predictive of conversion to syndromal psychosis than the timing of their emergence and intensification. These findings also suggest that the earliest phase of psychotic illness involves a rapid, dynamic process, beginning before the syndromal first episode, with potentially substantial implications for CHR research and understanding the neurobiology of psychosis.