It is not clear to what extent associations between schizophrenia, cannabis use and cigarette use are due to a shared genetic etiology. We, therefore, examined whether schizophrenia genetic risk associates with longitudinal patterns of cigarette and cannabis use in adolescence and mediating pathways for any association to inform potential reduction strategies.

Associations between schizophrenia polygenic scores and longitudinal latent classes of cigarette and cannabis use from ages 14 to 19 years were investigated in up to 3925 individuals in the Avon Longitudinal Study of Parents and Children. Mediation models were estimated to assess the potential mediating effects of a range of cognitive, emotional, and behavioral phenotypes.

The schizophrenia polygenic score, based on single nucleotide polymorphisms meeting a training-set p threshold of 0.05, was associated with late-onset cannabis use (OR = 1.23; 95% CI = 1.08,1.41), but not with cigarette or early-onset cannabis use classes. This association was not mediated through lower IQ, victimization, emotional difficulties, antisocial behavior, impulsivity, or poorer social relationships during childhood. Sensitivity analyses adjusting for genetic liability to cannabis or cigarette use, using polygenic scores excluding the CHRNA5-A3-B4 gene cluster, or basing scores on a 0.5 training-set p threshold, provided results consistent with our main analyses.

Our study provides evidence that genetic risk for schizophrenia is associated with patterns of cannabis use during adolescence. Investigation of pathways other than the cognitive, emotional, and behavioral phenotypes examined here is required to identify modifiable targets to reduce the public health burden of cannabis use in the population.

Antidepressants are amongst the most commonly prescribed classes of drugs and their use continues to grow. Adverse outcomes are part of the landscape in prescribing medications and therefore management of safety issues need to be an integral part of practice.

We have developed consensus guidelines for safety monitoring with antidepressant treatments.

To present an overview of screening and safety considerations for pharmacotherapy of clinical depressive disorders and make recommendations for safety monitoring.

Data were sourced by a literature search using Medline and a manual search of scientific journals to identify relevant articles. Draft guidelines were prepared and serially revised in an iterative manner until all co-authors gave final approval of content.

A guidelines document was produced after approval by all 19 co-authors. The final document gives guidance on; the decision to treat, baseline screening prior to commencement of treatment, and ongoing monitoring during antidepressant treatment. The guidelines state or reference screening protocols that may detect medical causes of depression as well as screening and monitoring protocols to investigate specific adverse effects associated with antidepressant treatments that may be reduced or identified earlier by baseline screening and agent-specific monitoring after commencing treatment.

The implementation of safety monitoring guidelines for treatment of clinical depression may significantly improve outcome, by improving a patient's overall physical health status.

Smoking prevalence is higher amongst individuals with schizophrenia and depression compared with the general population. Mendelian randomisation (MR) can examine whether this association is causal using genetic variants identified in genome-wide association studies (GWAS).

We conducted two-sample MR to explore the bi-directional effects of smoking on schizophrenia and depression. For smoking behaviour, we used (1) smoking initiation GWAS from the GSCAN consortium and (2) we conducted our own GWAS of lifetime smoking behaviour (which captures smoking duration, heaviness and cessation) in a sample of 462690 individuals from the UK Biobank. We validated this instrument using positive control outcomes (e.g. lung cancer). For schizophrenia and depression we used GWAS from the PGC consortium.

There was strong evidence to suggest smoking is a risk factor for both schizophrenia (odds ratio (OR) 2.27, 95% confidence interval (CI) 1.67–3.08, p < 0.001) and depression (OR 1.99, 95% CI 1.71–2.32, p < 0.001). Results were consistent across both lifetime smoking and smoking initiation. We found some evidence that genetic liability to depression increases smoking (β = 0.091, 95% CI 0.027–0.155, p = 0.005) but evidence was mixed for schizophrenia (β = 0.022, 95% CI 0.005–0.038, p = 0.009) with very weak evidence for an effect on smoking initiation.

These findings suggest that the association between smoking, schizophrenia and depression is due, at least in part, to a causal effect of smoking, providing further evidence for the detrimental consequences of smoking on mental health.

Pathological worry is a hallmark feature of generalised anxiety disorder (GAD), associated with dysfunctional emotional processing. The ventromedial prefrontal cortex (vmPFC) is involved in the regulation of such processes, but the link between vmPFC emotional responses and pathological v. adaptive worry has not yet been examined.

To study the association between worry and vmPFC activity evoked by the processing of learned safety and threat signals.

In total, 27 unmedicated patients with GAD and 56 healthy controls (HC) underwent a differential fear conditioning paradigm during functional magnetic resonance imaging.

Compared to HC, the GAD group demonstrated reduced vmPFC activation to safety signals and no safety–threat processing differentiation. This response was positively correlated with worry severity in GAD, whereas the same variables showed a negative and weak correlation in HC.

Poor vmPFC safety–threat differentiation might characterise GAD, and its distinctive association with GAD worries suggests a neural-based qualitative difference between healthy and pathological worries.

None.

Negative mood states are composed of symptoms of depression and anxiety, and by a third factor related to stress, tension and irritability. We sought to clarify the nature of the relationships between the factors by studying twin pairs.

A total of 503 monozygotic twin pairs completed the Depression Anxiety Stress Scales (DASS), an instrument that assesses symptoms of depression, anxiety and stress–tension. We applied a recently developed twin regression methodology – Inference about Causation from Examination of FAmiliaL CONfounding (ICE FALCON) – to test for evidence consistent with the existence of ‘causal’ influences between the DASS factors.

There was evidence consistent with the stress–tension factor having a causal influence on both the depression (p < 0.0001) and anxiety factors (p = 0.001), and for the depression factor having a causal influence on the anxiety factor (p < 0.001).

Our findings suggest a critical role for stress–tension in the structure of negative mood states, and that interventions that target it may be particularly effective in reducing depression and anxiety symptoms.

Current guidelines recommend that patients with CHD receive age-appropriate counselling on reproduction, pregnancy, and risk of heredity. Our aim was to examine patient knowledge of reproductive health and explore the association between patient knowledge of CHD transmission risk and earlier physician counselling in adults with CHD.

We performed a cross-sectional survey of patients with CHD aged 18 years and older in a paediatric hospital.

Of the 100 patients who completed the questionnaire, most did not report counselling on heredity (66%) or contraception (71%). Of the 54 women, 25 (46%) identified their contraceptive options correctly; 42 (78%) women were classified as being at significantly increased risk for an adverse outcome during pregnancy, and of these 20 (48%) identified this risk correctly. Of all patients surveyed, 72% did not know that having CHD placed them at increased risk for having a child with CHD. On multivariate analysis, factors associated with correct knowledge about risk of recurrence were correct identification of CHD diagnosis (p=0.04) and patient-reported counselling (p=0.001).

Knowledge about heredity, pregnancy risk, and contraceptive options is inadequate among adults with CHD followed-up in a paediatric subspecialty clinic. The majority of patients did not report a history of counselling about reproductive health. There is a strong correlation between history of counselling by the patient’s cardiologist and correct knowledge about recurrence risk, suggesting that effective reproductive counselling can positively impact this knowledge gap.

Obesity is a growing problem in India, the dietary determinants of which have been studied using an ‘individual food/nutrient’ approach. Examining dietary patterns may provide more coherent findings, but few studies in developing countries have adopted this approach. The present study aimed to identify dietary patterns in an Indian population and assess their relationship with anthropometric risk factors.

FFQ data from the cross-sectional sib-pair Indian Migration Study (IMS; n 7067) were used to identify dietary patterns using principal component analysis. Mixed-effects logistic regression was used to examine associations with obesity and central obesity.

The IMS was conducted at four factory locations across India: Lucknow, Nagpur, Hyderabad and Bangalore.

The participants were rural-to-urban migrant and urban non-migrant factory workers, their rural and urban resident siblings, and their co-resident spouses.

Three dietary patterns were identified: ‘cereals–savoury foods’ (cooked grains, rice/rice-based dishes, snacks, condiments, soups, nuts), ‘fruit–veg–sweets–snacks’ (Western cereals, vegetables, fruit, fruit juices, cooked milk products, snacks, sugars, sweets) and ‘animal-food’ (red meat, poultry, fish/seafood, eggs). In adjusted analysis, positive graded associations were found between the ‘animal-food’ pattern and both anthropometric risk factors. Moderate intake of the ‘cereals–savoury foods’ pattern was associated with reduced odds of obesity and central obesity.

Distinct dietary patterns were identified in a large Indian sample, which were different from those identified in previous literature. A clear ‘plant food-based/animal food-based pattern’ dichotomy emerged, with the latter being associated with higher odds of anthropometric risk factors. Longitudinal studies are needed to further clarify this relationship in India.

The amygdala and subgenual anterior cingulate cortex (sACC) are key brain regions for the generation of negative affect. In this longitudinal fMRI study of adolescents we investigated how amygdala–sACC connectivity was correlated with negative affectivity (NA) both cross-sectionally and longitudinally, and examined its relationship to the onset of first-episode depression.

Fifty-six adolescents who were part of a larger longitudinal study of adolescent development were included. They had no history of mental illness at the time of their baseline scan (mean age 16.5 years) and had a follow-up scan 2 years later (mean age 18.8 years). We used resting-state functional-connectivity MRI to investigate whether cross-sectional and change measures of amygdala–sACC connectivity were (i) correlated with NA and its change over time, and (ii) related to the onset of first-episode depression.

The magnitude of amygdala connectivity with sACC showed significant positive correlation with NA at both time-points. Further analysis confirmed that change in amygdala–sACC connectivity between assessments was correlated with change in NA. Eight participants developed a first episode of depression between the baseline and follow-up assessments: they showed increased amygdala–sACC connectivity at follow-up.

Amygdala–sACC connectivity is associated with NA in adolescence, with change in connectivity between these regions showing positive correlation with change in NA. Our observation that the onset of depression was associated with an increase in connectivity between the regions provides support for the neurobiological ‘scar’ hypothesis of depression.

Cigarette smoking is strongly associated with mental illness but the causal direction of the association is uncertain. We investigated the causal relationship between smoking and symptoms of anxiety and depression in the Norwegian HUNT study using the rs1051730 single nucleotide polymorphism (SNP) variant located in the nicotine acetylcholine receptor gene cluster on chromosome 15 as an instrumental variable for smoking phenotypes. Among smokers, this SNP is robustly associated with smoking quantity and nicotine dependence.

In total, 53 601 participants were genotyped for the rs1051730 SNP and provided information on smoking habits and symptoms of anxiety and depression using the Hospital Anxiety and Depression Scale (HADS).

Self-reported smoking was positively associated with the prevalence of both anxiety and depression, and the measured polymorphism was positively associated with being a current smoker and the number of cigarettes smoked in current smokers. In the sample as a whole, risk of anxiety increased with each affected T allele [odds ratio (OR) 1.06, 95% confidence interval (CI) 1.02–1.09, p = 0.002] but there was no association with depression (p = 0.31). However, we found no clear association of the polymorphism with either anxiety (OR 1.03, 95% CI 0.97–1.09, p = 0.34) or depression (OR 1.02, 95% CI 0.95–1.09, p = 0.62) among smokers.

As there was no association of the smoking-related rs1051730 SNP with anxiety and depression among smokers, the results suggest that smoking is not a cause of anxiety and depression.

Depression has been associated with functional alterations in several areas of the cingulate cortex. In this study we have taken a systematic approach to examining how alterations in functional connectivity vary across the functionally diverse subregions of the rostral cingulate cortex.

Eighteen patients with major depressive disorder, aged 15 to 24 years, were matched with 20 healthy control participants. Using resting-state functional connectivity magnetic resonance imaging (fcMRI), we systematically investigated the functional connectivity of four subregions of the rostral cingulate cortex. Voxelwise statistical maps of each subregion's connectivity with other brain areas were compared between the patient and control groups.

The depressed participants showed altered patterns of connectivity with ventral cingulate subregions. They showed increased connectivity between subgenual anterior cingulate cortex (ACC) and dorsomedial frontal cortex, with connectivity strength showing positive correlation with illness severity. Depressed participants also showed increased connectivity between pregenual ACC and left dorsolateral frontal cortex, and decreased connectivity between pregenual ACC and the caudate nucleus bilaterally.

The results reinforce the importance of subgenual ACC for depression, and show a close link between brain regions that support self-related processes and affective visceromotor function. The pregenual ACC also has an important role, with its increased connectivity with dorsolateral frontal cortex suggesting heightened cognitive regulation of affect; and reduced connectivity with the caudate nucleus potentially underlying symptoms such as anhedonia, reduced motivation and psychomotor dysfunction.

Abnormalities in cortico-striatal-pallidal-thalamic (CSPT) circuits have been implicated in major depressive disorder (MDD). However, the robustness of these findings across studies is unclear, as is the extent to which they are influenced by demographic, clinical and pharmacological factors.

With the aim of clarifying these questions, we conducted a meta-analysis to map the volumetric abnormalities that were most robustly identified in CSPT circuits of individuals with MDD. A systematic search identified 41 studies meeting our inclusion criteria.

There were significant volume reductions in prefrontal (especially orbitofrontal) and anterior cingulate cortices, and also in subcortical structures such as the caudate nucleus and putamen, with effect sizes ranging from small to moderate. The subgenual anterior cingulate and orbitofrontal cortices were significantly smaller in antidepressant-free samples compared to medicated patients. Late-life depression (LLD) tended to be associated with smaller volumes in circumscribed frontal and subcortical structures, with the most robust differences being found in thalamic volume.

Individuals with major depression demonstrate volumetric abnormalities of CSPT circuits. However, these observations may be restricted to certain subgroups, highlighting the clinical heterogeneity of the disorder. On the basis of this meta-analysis, CSPT abnormalities were more prominent in those with LLD whereas antidepressant use seemed to normalize certain cortical volumetric abnormalities.

Lower cognitive functioning in early childhood has been proposed as a risk factor for depression in later life but its association with depressive symptoms during adolescence has rarely been investigated. Our study examines the relationship between total intelligence quotient (IQ) score at age 8 years, and depressive symptoms at 11, 13, 14 and 17 years.

Study participants were 5250 children and adolescents from the Avon Longitudinal Study of Parents and their Children (ALSPAC), UK, for whom longitudinal data on depressive symptoms were available. IQ was assessed with the Wechsler Intelligence Scale for Children III, and self-reported depressive symptoms were measured with the Short Mood and Feelings Questionnaire (SMFQ).

Multi-level analysis on continuous SMFQ scores showed that IQ at age 8 years was inversely associated with depressive symptoms at age 11 years, but the association changed direction by age 13 and 14 years (age–IQ interaction, p<0.0001; age squared–IQ interaction, p<0.0001) when a higher IQ score was associated with a higher risk of depressive symptoms. This change in IQ effect was also found in relation to pubertal stage (pubertal stage–IQ interaction, 0.00049<p⩽0.038). At age 17 years, however, sex-specific differences emerged (sex–age squared–IQ interaction, p=0.0075). Whilst the risk effect of higher childhood IQ scores for depressive symptoms declined in females, and some analyses even supported an inverse association by age 17 years, it persisted in males.

Our results suggest that the association between cognitive ability in childhood and depressive symptoms in adolescence varies according to age and/or pubertal stage.