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Our understanding of ice algal responses to the recent changes in Arctic sea ice is impeded by limited field observations. In the present study, environmental characteristics of the landfast sea-ice zone as well as primary production and macromolecular composition of ice algae and phytoplankton were studied in the Kitikmeot Sea near Cambridge Bay in spring 2017. Averaged total chlorophyll-a (Chl-a) concentration was within the lower range reported previously for the same region, while daily carbon uptake rates of bottom-ice algae were significantly lower in this study than previously reported for the Arctic. Based on various indicators, the region's low nutrient concentrations appear to limit carbon uptake rates and associated accumulation of bottom-ice algal biomass. Furthermore, the lipids-dominant biochemical composition of bottom-ice algae suggests strong nutrient limitation relative to the distinctly different carbohydrates-dominant composition of phytoplankton. Together, the results confirm strong nitrate limitation of the local marine system.
The aim of this study was to examine whether the presence of risk alleles of the norepinephrine transporter gene (SLC6A2) polymorphisms is associated with differences in regional cerebral blood flow (rCBF) measured by 99mTc-HMPAO single photon emission computerized tomography in a Korean sample of ADHD.
The present study included 24 children with ADHD (9.5±2.4 years), consisting of 20 boys and 4 girls, aged 6-16 years. We investigated the G1287A and -3081(A/T) polymorphisms of the SLC6A2. The rCBF was compared between the ADHD subjects with and without risk alleles at the G1287A polymorphism and at the -3081(A/T) polymorphism. Image analyses were performed with voxelwise t-statistics using SPM2.
1) The ADHD subjects with the A allele (risk allele) at the G1287A polymorphism showed reduced perfusion in the left middle frontal gyrus, left inferior parietal lobule, precuneus, right superior frontal gyrus, and right superior parietal lobule as compared with ADHD subjects without the A allele (p< 0.001).
2) The ADHD subjects with the A allele at the G1287A polymorphism showed increased perfusion in the right middle frontal gyrus, right middle temporal gyrus, right superior temporal gyrus, right fusiform gyrus, right precentral gyrus, and right anterior lobe of cerebellum as compared with ADHD subjects without the A allele (p< 0.001).
3) No significant perfusion differences were found between ADHD subjects with and without the T allele (risk allele) at the -3081(A/T) polymorphism.
Our findings suggest that the SLC6A2 G1287A polymorphism might exert differential effects on rCBF in children with ADHD.
There are two major forms of long-term depression (LTD) of synaptic transmission in the central nervous system, which require activation of either N-methyl-D-aspartate receptors (NMDARs) or metabotropic glutamate receptors (mGluRs). In synapses in the perirhinal cortex we have directly compared the Ca2+ signalling mechanisms involved in NMDAR-LTD and mGluR-LTD. Whilst both forms of LTD involve Ca2+ release from intracellular stores the Ca2+ sensors involved are different; NMDAR-LTD involves calmodulin, whilst mGluR-LTD involves the neuronal Ca2+ sensor (NCS) protein NCS-1. In addition, there is a specific requirement for IP3 and PKC as well as protein interacting with C-kinase (PICK-1) in mGluR-LTD. NCS-1 binds directly to PICK1, via its BAR domain, in a Ca2+-dependent manner. Furthermore, the NCS-1-PICK1 association is stimulated by activation of mGluRs, but not NMDARs, and introduction of a PICK1 BAR domain fusion protein specifically blocks mGluR-LTD. Thus, NCS-1 is a component of a novel mechanism involved in mGluR-LTD.
There have been many changes in the treatment of bipolar disorder.
It is necessary to develop guidelines that can more aptly respond to cultural issues and specifics in different countries.
The Korean Medication Algorithm for Bipolar Disorder (KMAP-BP) was firstly published in 2002, with updates in 2006 and 2010. This third update reviewed the experts' consensus of opinion on the pharmacological treatments of bipolar disorder.
The newly revised questionnaire composed of 55 key questions about clinical situations including 223 sub-items was sent to the experts.
Combination of mood stabilizer (MS) and atypical antipsychotic (AAP) was the first-line treatment option in acute mania. For the management of severe psychotic bipolar depression, combination of MS and AAP, combination of AAP and LTG, combination of MS, AAP and AD or LTG, combination of AAP and AD, and combination of AAP, AD and LTG was the first-line treatments. Combination of MS and AAP was the treatment of choice for management of mixed features. Combination of MS and AAP, MS or AAP monotherapy was the first-line options for management of maintenance phase after manic episode. For maintenance treatment after bipolar I depression, combination of MS and AAP, combination of MS and LTG, combination of AAP and LTG, MS or LTG monotherapy, and combination of MS, AAP and LTG were the first-line options.
Despite the limitations of expert consensus guideline, KMAP-BP 2014 may reflect the current patterns of clinical practice and recent researches.
The aim of this study was to monitor changes of prescription trends for bipolar disorder in inpatient settings in one university hospital.
A retrospective chart review was performed and data of 188 cases (2009–2012) and 118 cases (1998–2001) with a diagnosis of bipolar disorder were collected. Data on demographic variables, duration of hospitalization, kinds of psychotropic medications and the patterns of prescription over each four-year period were analyzed.
The proportion of patients with manic episode was decreased, whereas those of mixed and depressive episodes were increased. The use of lithium was decreased with the increased use of valproate. Increased use of lamotrigine in depressive episode was prominent. The use of combination treatment with mood stabilizers and antipsychotics was almost same level in both periods. The use of typical antipsychotics was significantly decreased and that of atypical antipsychotics was increased. Especially, the use of quetiapine showed great increase. In bipolar depression, the use of antidepressant was increased.
Data showed that quetiapine monotherapy had favorable effect on acute manic symptoms and well tolerated. Also this result suggests that quetiapine monotherapy may improve the self-perceived quality of sleep without any daytime impairment following sleep in acute manic patients.
Life events and accompanying psychological and behavioral reactions frequently have an impact upon people's daily lives and are believed to predispose them to disease. Psychological stressors impact many physiological and pathological disease outcomes, including mental illness. Positive social interactions have in turn been shown to exert powerful beneficial effects on health outcomes and longevity.
The Objective of this study was to analyze the relationships of Psychological Distress, Social Support, and Mental Fitness among patients of mental health services.
This article aims to discuss the evidence supporting the mediating effect of social support between psychological stress and mental health.
This study was performed on patients who visited the mental health services in Daejeon from October to December 2011. In total, 395 patients were evaluated with Mental Fitness Scale, Kessler Psychological Distress Scale(KPDS), and Multidimensional Scale of Perceived Social Support(MSPSS).
Correlations among variables of psychological distress and social support on subordinate variable of mental fitness of patients were significant. The result of the regression analysis, psychological distress and social support have a positively significant influence on mental fitness of patients. social support showed mediating effects between psychological distress and mental fitness.
These results suggest that health care providers ought to seek social support for patients, in order to provide positive mental fitness of patients.
Despite the advance in pharmacotherapy for posttraumatic stress disorder (PTSD), poor treatment adherence to pharmacotherapy for PTSD is a critical issue.
We intended to evaluate the predictors of premature discontinuation of psychiatric outpatient treatment after discharge for noncombat-related PTSD.
This study aimed to examine the sociodemographic and disease-related variables associated with the premature discontinuation of psychiatric outpatient treatment after discharge among patients with non-combat-related posttraumatic stress disorder.
We retrospectively reviewed the medical records of patients who were discharged with a diagnosis of posttraumatic stress disorder.
Fifty-five percent of subjects prematurely discontinued outpatient treatment within 6 months of discharge. Comparing sociodemographic variables between the 6-month non-follow-up group and 6-month follow-up group, there were no variables that differed between the two groups. However, comparing disease-related variables, the 6-month follow-up group showed a longer hospitalization duration and higher Global Assessment of Function score at discharge. The logistic regression analysis showed that a shorter duration of hospitalization predicted premature discontinuation of outpatient treatment within 6 months of discharge.
The duration of psychiatric hospitalization for posttraumatic stress disorder appeared to influence the premature discontinuation of outpatient treatment after discharge.
This study examined the prescribing patterns for medications to treat bipolar disorder in outpatient-based psychiatric practice focusing on atypical antipsychotics.
Retrospective chart review of patients admitted to a university hospital with a primary diagnosis of bipolar disorder in a period from January 2008 to December 2012 was conducted. We reviewed Diagnostic and Statistical Manual of Mental Disorders, fourth edition diagnosis and detailed clinical information at index episode. Psychotropic medications were grouped into six categories; atypical antipsychotics, typical antipsychotics, lithium, anticonvulsants, antidepressants, and minor tranquilizers. Severity, rapid cycling type, psychiatric comorbidity and disease duration were computed focusing on atypical antipsychotics.
In 344 patients who were prescribed major psychotropic medications, atypical antipsychotics were prescribed in 70.9% of subjects, anticonvulsants in 73.3%, lithium in 36.9%, antidepressants in 41.9%, and typical antipsychotics in 0.9% of subjects. About 12.5% of subjects were treated with the monotherapy. Atypical antipsychotics prescription was favored in subjects with manic and mixed episodes or severe episode. Prescribing trend is independent of rapid cycling type. Prescription of antidepressants were more frequent in subjects who were recently diagnosed as bipolar disorder or prescribed new medications or existed psychiatric comorbidity.
The development of bipolar disorder's psychopharmacology has been reflected in the prescription pattern of psychotropic medications in Korea. This study suggests that atypical antipsychotics have played major role in treatment of bipolar disorder.
We evaluated the difference in sleep skills between patients with and without need of hypnotics after sleep CBT.
Total 131 insomnia patients' sleep disturbances were assessed by visual analogue scales. Patients received 9 sessions of sleep CBT and were prescribed hypnotics for prn during 3 months. Sleep CBT was focused on the sleep hygiene and sleep stimulus-control guidelines. Sleep hygiene guidelines were Limit the time spent in bed (SH1), Get regular exercise (SH2), Avoid light at night (SH3), Avoid heavy meals or drinking (SH4), Quiet, dark, and comfortable bedroom (SH5), Avoid caffeine, alcohol, and nicotine (SH6), Relaxing bedtime routine (SH7),Llight bedtime snack (SH8), Remove the bedroom clock (SH9). Sleep stimulus-control guidelines were Go to bed only when sleepy (SSC1), Use the bed for sleeping or sex (SSC2), Get out of bed when unable to sleep (SSC3), Get up at the same time (SSC4), Avoid napping (SSC5). Each sleep skill state was evaluated by Likert scale, and they were compared between before and after CBT. Patients were divided into two groups: still need of hypnotics and no need of hypnotics after 3 months.
Forty-six (35.1%) patients replied they needed not hypnotics any more, but 85 (64.9%) patients replied they still needed hypnotics after CBT. Sleep VAS (25.26±8.52 vs. 32.64±8.95, p<0.001), SH2 (3.67±0.92 vs. 2.76±1.06, p=0.030), SH7 (4.08±0.55 vs. 2.76±0.76, p<0.001) were different in two groups.
Among several CBT skills, regular moderate exercise in daytime and a relaxing bedtime routine seem to be key components.
Although a number of studies have examined the relationship between depression and obesity, it is still insufficient to establish the specific pattern of relationship between depression and body mass index (BMI) categories. Thus, this study was aimed to investigate the relationship between depression and BMI categories.
A cross-sectional study was conducted for a cohort of 159,390 Korean based on Kangbuk Samsung Health Study (KSHS). Study participants were classified into 5 groups by Asian-specific cut-off of BMI (18.5, 23, 25 and 30 kg/m2). The presence of depression was determined by Center for Epidemiologic Studies-Depression scales (CES-D) = 16 and = 25. The adjusted odd ratios (ORs) for depression were evaluated by multiple logistic regression analysis, in which independent variable was 5 categories of BMI and dependent variable was depression. Subgroup analysis was conducted by gender and age.
When normal group was set as a reference, the adjusted ORs for depression formed U-shaped pattern of relationship with BMI categories [underweight: 1.31 (1.14–1.50), overweight: 0.94 (0.85–1.04), obese group: 1.01 (0.91–1.12), severe obese group: 1.28 (1.05–1.54)]. This pattern of relationship was more prominent in female and young age group than male and elderly subgroup. BMI level with the lowest likelihood of depression was 18.5 kg/m2 to 25 kg/m2 in women and 23 kg/m2 to 25 kg/m2 in men.
There was a U-shaped relationship between depression and BMI categories. This finding suggests that both underweight and severe obesity are associated with the increased risk for depression.
The objective of this family-based whole exome sequencing (WES) is to examine genetic variants of autism spectrum disorder (ASD) in Korean population.
The probands with ASD and their biological parents were recruited in this study. We ascertained diagnosis based on DSM-5™ criteria, using Autism Diagnostic Observation Schedule and Autism Diagnostic Interview–Revised. We selected probands with typical phenotypes of ASD both in social interaction/communication and repetitive behaviour/limited interest domains, with intellectual disability (IQ < 70), for attaining homogeneity of the phenotypes. First, we performed WES minimum 50× for 13 probands and high-coverage pooled sequencing for their parents. We performed additional WES for 38 trio families, at least 100× depth. De novo mutations were confirmed by Sanger sequencing. All the sequence reads were mapped onto the human reference genome (hg19 without Y chromosome). Bioinformatics analyses were performed by BWA-MEM, Picard, GATK, and snpEff for variant annotation. We selected de novo mutation candidates from probands, which are neither detected in two pooled samples nor both parents.
Fifty-one subjects with ASD (5 females, 40∼175 months, mean IQ 42) and their families were included in this study. We discovered 109 de novo variants from 46 families. Twenty-nine variants are expected to be amino acid changing, potentially causing deleterious effects. We assume CELSR3, MYH1, ATXN1, IDUA, NFKB1, and C4A/C4B may have adverse effect on central nerve system.
We observed novel de novo variants which are assumed to contribute to development of ASD with typical phenotypes and low intelligence in WES study.
Disclosure of interest
This work has been supported by Healthcare Technology R&D project (No: A120029) by Ministry of Health and Welfare, Republic of Korea.
While previous studies have described career outcomes of physician-scientist trainees after graduation, trainee perceptions of research-intensive career pathways remain unclear. This study sought to identify the perceived interests, factors, and challenges associated with academic and research careers among predoctoral MD trainees, MD trainees with research-intense (>50%) career intentions (MD-RI), and MD-PhD trainees.
A 70-question survey was administered to 16,418 trainees at 32 academic medical centers from September 2012 to December 2014. MD vs. MD-RI (>50% research intentions) vs. MD-PhD trainee responses were compared by chi-square tests. Multivariate logistic regression analyses were performed to identify variables associated with academic and research career intentions.
There were 4433 respondents (27% response rate), including 2625 MD (64%), 653 MD-RI (15%), and 856 MD-PhD (21%) trainees. MD-PhDs were most interested in pursuing academia (85.8%), followed by MD-RIs (57.3%) and MDs (31.2%). Translational research was the primary career intention for MD-PhD trainees (42.9%). Clinical duties were the primary career intention for MD-RIs (51.9%) and MDs (84.2%). While 39.8% of MD-PhD respondents identified opportunities for research as the most important career selection factor, only 12.9% of MD-RI and 0.5% of MD respondents shared this perspective. Interest in basic research, translational research, clinical research, education, and the ability to identify a mentor were each independently associated with academic career intentions by multivariate regression.
Predoctoral MD, MD-RI, and MD-PhD trainees are unique cohorts with different perceptions and interests toward academic and research careers. Understanding these differences may help to guide efforts to mentor the next generation of physician-scientists.
Cognitive impairment associated with lifetime major depressive disorder (MDD) is well-supported by meta-analytic studies, but population-based estimates remain scarce. Previous UK Biobank studies have only shown limited evidence of cognitive differences related to probable MDD. Using updated cognitive and clinical assessments in UK Biobank, this study investigated population-level differences in cognitive functioning associated with lifetime MDD.
Associations between lifetime MDD and cognition (performance on six tasks and general cognitive functioning [g-factor]) were investigated in UK Biobank (N-range 7,457–14,836, age 45–81 years, 52% female), adjusting for demographics, education, and lifestyle. Lifetime MDD classifications were based on the Composite International Diagnostic Interview. Within the lifetime MDD group, we additionally investigated relationships between cognition and (a) recurrence, (b) current symptoms, (c) severity of psychosocial impairment (while symptomatic), and (d) concurrent psychotropic medication use.
Lifetime MDD was robustly associated with a lower g-factor (β = −0.10, PFDR = 4.7 × 10−5), with impairments in attention, processing speed, and executive functioning (β ≥ 0.06). Clinical characteristics revealed differential profiles of cognitive impairment among case individuals; those who reported severe psychosocial impairment and use of psychotropic medication performed worse on cognitive tests. Severe psychosocial impairment and reasoning showed the strongest association (β = −0.18, PFDR = 7.5 × 10−5).
Findings describe small but robust associations between lifetime MDD and lower cognitive performance within a population-based sample. Overall effects were of modest effect size, suggesting limited clinical relevance. However, deficits within specific cognitive domains were more pronounced in relation to clinical characteristics, particularly severe psychosocial impairment.
Heat shock proteins (HSPs) consist of highly preserved stress proteins that are expressed in response to stress. Two studies were carried out to investigate whether HSP genes in hair follicles from beef calves can be suggested as indicators of heat stress (HS). In study 1, hair follicles were harvested from three male Hanwoo calves (aged 172.2 ± 7.20 days) on six dates over the period of 10 April to 9 August 2017. These days provided varying temperature–humidity indices (THIs). In study 2, 16 Hanwoo male calves (aged 169.6 ± 4.60 days, with a BW of 136.9 ± 6.23 kg) were maintained (4 calves per experiment) in environmentally controlled chambers. A completely randomized design with a 2 × 4 factorial arrangement involving two periods (thermoneutral: TN; HS) and four THI treatment groups (threshold: THI = 68 to 70; mild: THI = 74 to 76; moderate THI = 81 to 83; severe: THI = 88 to 90). The calves in the different group were subjected to ambient temperature (22°C) for 7 days (TN) and subsequently to the temperature and humidity corresponding to the target THI level for 21 days (HS). Every three days (at 1400 h) during both the TN and HS periods, the heart rate (HR) and rectal temperature (RT) of each individual were measured, and hair follicles were subsequently collected from the tails of each individual. In study 1, the high variation (P < 0.0001) in THI indicated that the external environment influenced the HS to different extents. The expression levels of the HSP70 and HSP90 genes at the high-THI level were higher (P = 0.0120, P = 0.0002) than those at the low-THI level. In study 2, no differences in the THI (P = 0.2638), HR (P = 0.2181) or RT (P = 0.3846) were found among the groups during the TN period, whereas differences in these indices (P < 0.0001, P < 0.0001 and P < 0.0001, respectively) were observed during the HS period. The expression levels of the HSP70 (P = 0.0010, moderate; P = 0.0065, severe) and HSP90 (P = 0.0040, severe) genes were increased after rapid exposure to heat-stress conditions (moderate and severe levels). We conclude that HSP gene expression in hair follicles provides precise and accurate data for evaluating HS and can be considered a novel indicator of HS in Hanwoo calves maintained in both external and climatic chambers.
Studies suggest that alcohol consumption and alcohol use disorders have distinct genetic backgrounds.
We examined whether polygenic risk scores (PRS) for consumption and problem subscales of the Alcohol Use Disorders Identification Test (AUDIT-C, AUDIT-P) in the UK Biobank (UKB; N = 121 630) correlate with alcohol outcomes in four independent samples: an ascertained cohort, the Collaborative Study on the Genetics of Alcoholism (COGA; N = 6850), and population-based cohorts: Avon Longitudinal Study of Parents and Children (ALSPAC; N = 5911), Generation Scotland (GS; N = 17 461), and an independent subset of UKB (N = 245 947). Regression models and survival analyses tested whether the PRS were associated with the alcohol-related outcomes.
In COGA, AUDIT-P PRS was associated with alcohol dependence, AUD symptom count, maximum drinks (R2 = 0.47–0.68%, p = 2.0 × 10−8–1.0 × 10−10), and increased likelihood of onset of alcohol dependence (hazard ratio = 1.15, p = 4.7 × 10−8); AUDIT-C PRS was not an independent predictor of any phenotype. In ALSPAC, the AUDIT-C PRS was associated with alcohol dependence (R2 = 0.96%, p = 4.8 × 10−6). In GS, AUDIT-C PRS was a better predictor of weekly alcohol use (R2 = 0.27%, p = 5.5 × 10−11), while AUDIT-P PRS was more associated with problem drinking (R2 = 0.40%, p = 9.0 × 10−7). Lastly, AUDIT-P PRS was associated with ICD-based alcohol-related disorders in the UKB subset (R2 = 0.18%, p < 2.0 × 10−16).
AUDIT-P PRS was associated with a range of alcohol-related phenotypes across population-based and ascertained cohorts, while AUDIT-C PRS showed less utility in the ascertained cohort. We show that AUDIT-P is genetically correlated with both use and misuse and demonstrate the influence of ascertainment schemes on PRS analyses.
Light Detection and Ranging (LiDAR) is a primary sensor for autonomous vehicles to recognize surroundings. It detects near-infrared (NIR) light pulses, typically at 905nm, which is emitted and reflected by surrounding objects. Here, the fact of the matter is that conventional black or dark-tone cars with extremely low NIR reflection are hard to be detected by LiDAR and endanger the future highway. In this work, we propose to use platelet-shaped effect pigments with visible absorption and NIR reflectivity. Copper(Ⅱ) oxide and Silicon dioxide multilayer are theoretically investigated with different numbers of layers and thicknesses. The optimized structures appear various dark-tone colors with high NIR-reflectivity over 90%.
To ascertain the distribution of Ménière's disease phenotype subgroups in a US-based cohort, based on a recently introduced classification scheme utilising a Spanish and Portuguese cohort.
A retrospective, cross-sectional, single-institutional chart review was conducted. The electronic medical records of Ménière's disease patients were identified using International Classification of Diseases codes at a tertiary referral centre and reviewed to extract subgroup-defining features. Patients with definite Ménière's disease as per American Academy of Otolaryngology–Head and Neck Surgery criteria were categorised into one of five subgroups, for unilateral and bilateral Ménière's disease.
Eighty-one patients with definite Ménière's disease were identified. Seventy-two cases of unilateral Ménière's disease were observed: 52.8 per cent were type 1, 20.8 per cent were type 2, 4.2 per cent were type 3, 18.1 per cent were type 4, and 4.2 per cent were type 5. This cohort differed significantly in distribution to a comparison Mediterranean cohort (p < 0.01). Nine cases of bilateral Ménière's disease were observed.
The distribution of unilateral Ménière's disease subtypes in this US population was different from that observed in a European population.
Guidelines recommend empowering patients and families to remind healthcare workers (HCWs) to perform hand hygiene (HH). The effectiveness of empowerment tools for patients and their families in Southeast Asia is unknown.
We performed a prospective study in a pediatric intensive care unit (PICU) of a Vietnamese pediatric referral hospital. With family and HCW input, we developed a visual tool for families to prompt HCW HH. We used direct observation to collect baseline HH data. We then enrolled families to receive the visual tool and education on its use while continuing prospective collection of HH data. Multivariable logistic regression was used to identify independent predictors of HH in baseline and implementation periods.
In total, 2,014 baseline and 2,498 implementation-period HH opportunities were observed. During the implementation period, 73 families were enrolled. Overall, HCW HH was 46% preimplementation, which increased to 73% in the implementation period (P < .001). The lowest HH adherence in both periods occurred after HCW contact with patient surroundings: 16% at baseline increased to 24% after implementation. In multivariable analyses, the odds of HCW HH during the implementation period were significantly higher than baseline (adjusted odds ratio [aOR], 2.94; 95% confidence interval [CI], 2.54–3.41; P < .001) after adjusting for observation room, HCW type, time of observation (weekday business hours vs evening or weekend), and HH moment.
The introduction of a visual empowerment tool was associated with significant improvement in HH adherence among HCWs in a Vietnamese PICU. Future research should explore acceptability and barriers to use of similar tools in low- and middle-income settings.
Major depressive disorder and neuroticism (Neu) share a large genetic basis. We sought to determine whether this shared basis could be decomposed to identify genetic factors that are specific to depression.
We analysed summary statistics from genome-wide association studies (GWAS) of depression (from the Psychiatric Genomics Consortium, 23andMe and UK Biobank) and compared them with GWAS of Neu (from UK Biobank). First, we used a pairwise GWAS analysis to classify variants as associated with only depression, with only Neu or with both. Second, we estimated partial genetic correlations to test whether the depression's genetic link with other phenotypes was explained by shared overlap with Neu.
We found evidence that most genomic regions (25/37) associated with depression are likely to be shared with Neu. The overlapping common genetic variance of depression and Neu was genetically correlated primarily with psychiatric disorders. We found that the genetic contributions to depression, that were not shared with Neu, were positively correlated with metabolic phenotypes and cardiovascular disease, and negatively correlated with the personality trait conscientiousness. After removing shared genetic overlap with Neu, depression still had a specific association with schizophrenia, bipolar disorder, coronary artery disease and age of first birth. Independent of depression, Neu had specific genetic correlates in ulcerative colitis, pubertal growth, anorexia and education.
Our findings demonstrate that, while genetic risk factors for depression are largely shared with Neu, there are also non-Neu-related features of depression that may be useful for further patient or phenotypic stratification.