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INTRODUCTION: Establishing valid diagnostic strategies is a precondition for successful therapeutic intervention in Alzheimer's disease (AD). METHODS: One hundred forty‐four healthy 75‐year‐old participants from the Vienna‐Transdanube‐Aging longitudinal cohort study were tested for neuroaxonal damage by single molecular array (Simoa) plasma neurofilament light chain (NfL) levels at baseline, 30, 60, and 90 months, and onset of AD dementia. Individual risk for sporadic AD was estimated by continuous shrinkage polygenic risk score (PRS‐CS, genome‐wide association study). RESULTS: Nineteen participants developed AD after a median of 60 months (interquartile range 30). In participants with AD, baseline NfL plasma levels correlated with PRS‐CS (r = 0.75, p < 0.001; difference to controls: Fisher's r‐to‐z: z = 3.89, p < 0.001). PRS‐CS combined with baseline plasma NfL predicted onset of AD (p < 0.01). DISCUSSION: Our data suggest that polygenic risk for AD and plasma NfL closely interact years before onset of clinical symptoms. Peripheral NfL may serve as a diagnostic measure supporting early therapeutic intervention and secondary prevention in AD. [ABSTRACT FROM AUTHOR]

This study investigated the recently reported association between alcohol dependence and accelerated ageing and the potential effects of abstinence and relapse on DNA methylation status using Levine's epigenetic clock to estimate DNA methylation age in two independent cohorts. The first sample comprised 88 (15 female) detoxified patients with alcohol use disorder (AUD) and 32 (5 female) healthy control (CON) subjects (NCT02615977), and the second included 69 (10 female) AUD patients that were followed up for 12 months with respect to relapse (n = 38, 4 female) and abstinence (n = 31, 6 female) (NCT01679145). To account for the different aspects of ageing captured by various clocks, we performed additional analyses of the first-generation Horvath clock and next-generation Zhang clock. To account for the genetic liability of AUD and its potential influence on DNA methylation, we calculated a polygenic risk score for alcohol dependence. We found that ageing was accelerated by 3.64 years in AUD patients compared with the CON group according to Levine's DNAm PhenoAge. Furthermore, in a second longitudinal sample, we found that abstaining AUD patients displayed a decrease in DNAm PhenoAge by 3.1 years, but we found an over proportional increase by 2.7 years in those who relapsed. Polygenic risk did not affect epigenetic ageing within our sample. These results confirm the age acceleration associated with AUD and provide the first evidence for a recovery of this effect upon abstinence from alcohol. [ABSTRACT FROM AUTHOR]

Background: While drinking alcohol, one must choose between the immediate rewarding effects and the delayed reward of a healthier lifestyle. Individuals differ in their devaluation of a delayed reward based on the time required to receive it, i.e., delay discounting (DD). Previous studies have shown that adolescents discount more steeply than adults and that steeper DD is associated with heavier alcohol use in both groups. Methods: In a large‐scale longitudinal study, we investigated whether higher rates of DD are an antecedent or a consequence of alcohol use during adolescent development. As part of the IMAGEN project, 2220 adolescents completed the Monetary Choice Questionnaire as a DD measure, the Alcohol Use Disorders Identification Test, and the Timeline Follow Back interview at ages 14, 16, 18, and 22. Bivariate latent growth curve models were applied to investigate the relationship between DD and drinking. To explore the consequences of drinking, we computed the cumulative alcohol consumption and correlated it with the development of discounting. A subsample of 221 participants completed an intertemporal choice task (iTeCh) during functional magnetic resonance imaging at ages 14, 16, and 18. Repeated‐measures ANOVA was used to differentiate between high‐risk and low‐risk drinkers on the development of neural processing during intertemporal choices. Results: Overall, high rates of DD at age 14 predicted a greater increase in drinking over 8 years. In contrast, on average, moderate alcohol use did not affect DD from ages 14 to 22. Of note, we found indicators for less brain activity in top‐down control areas during intertemporal choices in the participants who drank more. Conclusions: Steep DD was shown to be a predictor rather than a consequence of alcohol use in low‐level drinking adolescents. Important considerations for future longitudinal studies are the sampling strategies to be used and the reliability of the assessments. [ABSTRACT FROM AUTHOR]

Eating disorders and substance use disorders frequently co-occur. Twin studies reveal shared genetic variance between liabilities to eating disorders and substance use, with the strongest associations between symptoms of bulimia nervosa and problem alcohol use (genetic correlation [rg ], twin-based = 0.23-0.53). We estimated the genetic correlation between eating disorder and substance use and disorder phenotypes using data from genome-wide association studies (GWAS). Four eating disorder phenotypes (anorexia nervosa [AN], AN with binge eating, AN without binge eating, and a bulimia nervosa factor score), and eight substance-use-related phenotypes (drinks per week, alcohol use disorder [AUD], smoking initiation, current smoking, cigarettes per day, nicotine dependence, cannabis initiation, and cannabis use disorder) from eight studies were included. Significant genetic correlations were adjusted for variants associated with major depressive disorder and schizophrenia. Total study sample sizes per phenotype ranged from ~2400 to ~537 000 individuals. We used linkage disequilibrium score regression to calculate single nucleotide polymorphism-based genetic correlations between eating disorder- and substance-use-related phenotypes. Significant positive genetic associations emerged between AUD and AN (rg = 0.18; false discovery rate q = 0.0006), cannabis initiation and AN (rg = 0.23; q < 0.0001), and cannabis initiation and AN with binge eating (rg = 0.27; q = 0.0016). Conversely, significant negative genetic correlations were observed between three nondiagnostic smoking phenotypes (smoking initiation, current smoking, and cigarettes per day) and AN without binge eating (rgs = -0.19 to -0.23; qs < 0.04). The genetic correlation between AUD and AN was no longer significant after co-varying for major depressive disorder loci. The patterns of association between eating disorder- and substance-use-related phenotypes highlights the potentially complex and substance-specific relationships among these behaviors. [ABSTRACT FROM AUTHOR]

Previous studies demonstrated higher discount rates for delayed rewards in smokers than non-smokers. We performed this study to determine whether those differences in intertemporal choice are due to pharmacological effects of nicotine and to track related brain regions. Thirty-three non-smokers and 27 nicotine-dependent smokers underwent functional magnetic resonance imaging while performing an intertemporal choice task consisting of 40 sets of monetary reward options that varied by delay to delivery. Smokers were investigated in a state of nicotine satiation. Non-smokers were investigated twice, receiving nicotine (2 mg) and placebo gums in a double-blinded, randomized cross-over design. Smokers displayed steeper temporal discounting than non-smokers. Those behavioural differences were reflected in the brain response during the decision between two alternative money/time pairs: smokers showed less activation in parietal and occipital areas (e.g. precuneus) than non-smokers under placebo. A single dose of nicotine in non-smokers led to a similar effect on brain activation but did not impact behaviour. Processing of the reward magnitude of money/time pairs differed between smokers and non-smokers: smokers showed decreased reactivity of the ventral striatum. Moreover, there was an acute nicotine effect in non-smokers on processing of the reward magnitude: nicotine increased the correlation of blood oxygen level-dependent response and mean amount in the left hippocampus, amygdala and anterior insula. We conclude that cross-sectional differences between smokers and non-smokers are only, in part, due to the acute pharmacological effects of nicotine. Longitudinal studies are needed to investigate pre-drug group characteristics as well as consequences of smoking on discounting behaviour and its neural correlates. [ABSTRACT FROM AUTHOR]

Objectives Family and genetic studies indicate overlapping liability for major depressive disorder and bipolar disorder. The purpose of the present study was to determine whether this shared genetic liability influences clinical presentation. Methods A polygenic risk score for bipolar disorder, derived from a large genome-wide association meta-analysis, was generated for each subject of European-American ancestry (n = 1,274) in the Sequential Treatment Alternatives to Relieve Depression study (STAR*D) outpatient major depressive disorder cohort. A hypothesis-driven approach was used to test for association between bipolar disorder risk score and features of depression associated with bipolar disorder in the literature. Follow-up analyses were performed in two additional cohorts. Results A generalized linear mixed model including seven features hypothesized to be associated with bipolar spectrum illness was significantly associated with bipolar polygenic risk score [ F = 2.07, degrees of freedom (df) = 7, p = 0.04]. Features included early onset, suicide attempt, recurrent depression, atypical depression, subclinical mania, subclinical psychosis, and severity. Post-hoc univariate analyses demonstrated that the major contributors to this omnibus association were onset of illness at age ≤ 18 years [odds ratio (OR) = 1.2, p = 0.003], history of suicide attempt (OR = 1.21, p = 0.03), and presence of at least one manic symptom (OR = 1.16, p = 0.02). The maximal variance in these traits explained by polygenic score ranged from 0.8% to 1.1%. However, analyses in two replication cohorts testing a five-feature model did not support this association. Conclusions Bipolar genetic loading appeared to be associated with bipolar-like presentation in major depressive disorder in the primary analysis. However, the results were at most inconclusive because of lack of replication. Replication efforts were challenged by different ascertainment and assessment strategies in the different cohorts. The methodological approach described here may prove useful in applying genetic data to clarify psychiatric nosology in future studies. [ABSTRACT FROM AUTHOR]

Objective To identify genetic determinants of granulomatosis with polyangiitis (Wegener's) (GPA). Methods We carried out a genome-wide association study (GWAS) of 492 GPA cases and 1,506 healthy controls (white subjects of European descent), followed by replication analysis of the most strongly associated signals in an independent cohort of 528 GPA cases and 1,228 controls. Results Genome-wide significant associations were identified in 32 single-nucleotide polymorphic (SNP) markers across the HLA region, the majority of which were located in the HLA-DPB1 and HLA-DPA1 genes encoding the class II major histocompatibility complex (MHC) DPβ chain 1 and DPα chain 1 proteins, respectively. Peak association signals in these 2 genes, emanating from SNPs rs9277554 (for DPβ chain 1) and rs9277341 (DPα chain 1) were strongly replicated in an independent cohort (in the combined analysis of the initial cohort and the replication cohort, P = 1.92 × 10−50 and 2.18 × 10−39, respectively). Imputation of classic HLA alleles and conditional analyses revealed that the SNP association signal was fully accounted for by the classic HLA-DPB1*04 allele. An independent single SNP, rs26595, near SEMA6A (the gene for semaphorin 6A) on chromosome 5, was also associated with GPA, reaching genome-wide significance in a combined analysis of the GWAS and replication cohorts ( P = 2.09 × 10−8). Conclusion We identified the SEMA6A and HLA-DP loci as significant contributors to risk for GPA, with the HLA-DPB1*04 allele almost completely accounting for the MHC association. These two associations confirm the critical role of immunogenetic factors in the development of GPA. [ABSTRACT FROM AUTHOR]

Substance use disorders (SUDs) are seen as a continuum ranging from goal-directed and hedonic drug use to loss of control over drug intake with aversive consequences for mental and physical health and social functioning. The main goals of our interdisciplinary German collaborative research centre on Losing and Regaining Control over Drug Intake (ReCoDe) are (i) to study triggers (drug cues, stressors, drug priming) and modifying factors (age, gender, physical activity, cognitive functions, childhood adversity, social factors, such as loneliness and social contact/interaction) that longitudinally modulate the trajectories of losing and regaining control over drug consumption under real-life conditions. (ii) To study underlying behavioural, cognitive and neurobiological mechanisms of disease trajectories and drug-related behaviours and (iii) to provide non-invasive mechanism-based interventions. These goals are achieved by: (A) using innovative mHealth (mobile health) tools to longitudinally monitor the effects of triggers and modifying factors on drug consumption patterns in real life in a cohort of 900 patients with alcohol use disorder. This approach will be complemented by animal models of addiction with 24/7 automated behavioural monitoring across an entire disease trajectory; i.e. from a naïve state to a drug-taking state to an addiction or resilience-like state. (B) The identification and, if applicable, computational modelling of key molecular, neurobiological and psychological mechanisms (e.g., reduced cognitive flexibility) mediating the effects of such triggers and modifying factors on disease trajectories. (C) Developing and testing non-invasive interventions (e.g., Just-In-Time-Adaptive-Interventions (JITAIs), various non-invasive brain stimulations (NIBS), individualized physical activity) that specifically target the underlying mechanisms for regaining control over drug intake. Here, we will report on the most important results of the first funding period and outline our future research strategy., (© 2024 The Author(s). Addiction Biology published by John Wiley & Sons Ltd on behalf of Society for the Study of Addiction.)

It is imperative to understand the specific and shared etiologies of major depression and cardio-metabolic disease, as both traits are frequently comorbid and each represents a major burden to society. This study examined whether there is a genetic association between major depression and cardio-metabolic traits and if this association is stratified by age at onset for major depression. Polygenic risk scores analysis and linkage disequilibrium score regression was performed to examine whether differences in shared genetic etiology exist between depression case control status (N cases = 40,940, N controls = 67,532), earlier (N = 15,844), and later onset depression (N = 15,800) with body mass index, coronary artery disease, stroke, and type 2 diabetes in 11 data sets from the Psychiatric Genomics Consortium, Generation Scotland, and UK Biobank. All cardio-metabolic polygenic risk scores were associated with depression status. Significant genetic correlations were found between depression and body mass index, coronary artery disease, and type 2 diabetes. Higher polygenic risk for body mass index, coronary artery disease, and type 2 diabetes was associated with both early and later onset depression, while higher polygenic risk for stroke was associated with later onset depression only. Significant genetic correlations were found between body mass index and later onset depression, and between coronary artery disease and both early and late onset depression. The phenotypic associations between major depression and cardio-metabolic traits may partly reflect their overlapping genetic etiology irrespective of the age depression first presents., (© 2020 The Authors. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics published by Wiley Periodicals LLC.)

Background: Intracranial aneurysms (IAs), abdominal aortic aneurysms (AAAs), and thoracic aortic aneurysms (TAAs) all have a familial predisposition. Given that aneurysm types are known to co-occur, we hypothesized that there may be shared genetic risk factors for IAs, AAAs, and TAAs., Methods and Results: We performed a mega-analysis of 1000 Genomes Project-imputed genome-wide association study (GWAS) data of 4 previously published aneurysm cohorts: 2 IA cohorts (in total 1516 cases, 4305 controls), 1 AAA cohort (818 cases, 3004 controls), and 1 TAA cohort (760 cases, 2212 controls), and observed associations of 4 known IA, AAA, and/or TAA risk loci (9p21, 18q11, 15q21, and 2q33) with consistent effect directions in all 4 cohorts. We calculated polygenic scores based on IA-, AAA-, and TAA-associated SNPs and tested these scores for association to case-control status in the other aneurysm cohorts; this revealed no shared polygenic effects. Similarly, linkage disequilibrium-score regression analyses did not show significant correlations between any pair of aneurysm subtypes. Last, we evaluated the evidence for 14 previously published aneurysm risk single-nucleotide polymorphisms through collaboration in extended aneurysm cohorts, with a total of 6548 cases and 16 843 controls (IA) and 4391 cases and 37 904 controls (AAA), and found nominally significant associations for IA risk locus 18q11 near RBBP8 to AAA (odds ratio [OR]=1.11; P=4.1×10(-5)) and for TAA risk locus 15q21 near FBN1 to AAA (OR=1.07; P=1.1×10(-3))., Conclusions: Although there was no evidence for polygenic overlap between IAs, AAAs, and TAAs, we found nominally significant effects of two established risk loci for IAs and TAAs in AAAs. These two loci will require further replication., (© 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)

Objective: To identify genetic determinants of granulomatosis with polyangiitis (Wegener's) (GPA)., Methods: We carried out a genome-wide association study (GWAS) of 492 GPA cases and 1,506 healthy controls (white subjects of European descent), followed by replication analysis of the most strongly associated signals in an independent cohort of 528 GPA cases and 1,228 controls., Results: Genome-wide significant associations were identified in 32 single-nucleotide polymorphic (SNP) markers across the HLA region, the majority of which were located in the HLA-DPB1 and HLA-DPA1 genes encoding the class II major histocompatibility complex (MHC) DPβ chain 1 and DPα chain 1 proteins, respectively. Peak association signals in these 2 genes, emanating from SNPs rs9277554 (for DPβ chain 1) and rs9277341 (DPα chain 1) were strongly replicated in an independent cohort (in the combined analysis of the initial cohort and the replication cohort, P = 1.92 × 10(-50) and 2.18 × 10(-39) , respectively). Imputation of classic HLA alleles and conditional analyses revealed that the SNP association signal was fully accounted for by the classic HLA-DPB1*04 allele. An independent single SNP, rs26595, near SEMA6A (the gene for semaphorin 6A) on chromosome 5, was also associated with GPA, reaching genome-wide significance in a combined analysis of the GWAS and replication cohorts (P = 2.09 × 10(-8) )., Conclusion: We identified the SEMA6A and HLA-DP loci as significant contributors to risk for GPA, with the HLA-DPB1*04 allele almost completely accounting for the MHC association. These two associations confirm the critical role of immunogenetic factors in the development of GPA., (Copyright © 2013 by the American College of Rheumatology.)

Glutamate decarboxylase (GAD) is the rate limiting enzyme for conversion of glutamic acid to gamma-aminobutyric acid (GABA). The GAD 65 kDa isoform is encoded by the gene GAD2 and is mainly expressed in synaptic terminals. It serves as an apoenzyme, which shows enhanced availability in situations of stress, responding to short-term demands for GABA. We analyzed 18 single nucleotide polymorphisms (SNPs) in the GAD2-gene region for associations with psychiatric diagnosis and behavioral inhibition (BI) derived from the personality traits neuroticism and extraversion as defined by the Eysenck Personality Questionaire (EPQ). A total of 268 patients with anxiety disorder (AD), 541 with unipolar depression (MD), and 541 healthy controls were included. We observe associations for five tag-SNPs with BI in the AD- and control samples as well as two additional case-control associations in the MD-sample. The associated SNPs lie within a 16KB linkage disequilibrium-block, including putative 5' GAD2-promoter-elements as well as the 3' end of the gene MYO3A. Using open access mRNA-expression data, we could show that BI-associated SNPs appear to be associated with differences in MYO3A- but not GAD2 lymphoblastoid-mRNA expression levels. These results support earlier studies that suggest associations of polymorphisms within the GAD2 locus with anxiety and affective disorders. However, data from expression studies imply that these polymorphisms could tag functional effects on the neighboring gene MYO3A, which is also expressed in the brain, including the cingulate cortex and the amygdala., (2009 Wiley-Liss, Inc.)

Dispositional coping styles are important moderators of the stress reaction and are altered in stress-related disorders like cardiovascular diseases and affective disorders. Heritability studies suggest a considerable genetic contribution to the interindividual variability in coping styles. Since the angiotensin-converting enzyme (ACE) gene has been described to be associated with the vulnerability for stress-related disorders and with altered stress hormone regulation, we investigated the ACE gene as potential candidate gene for coping styles. Five hundred forty one mentally healthy subjects and 194 patients suffering from depression participating in the Munich Antidepressant Response Signature (MARS) project were examined. Coping styles were assessed with a self-report questionnaire (German Stress Coping Questionnaire SVF78) measuring the individual coping style pattern in response to stressful situations. We genotyped 15 single nucleotide polymorphisms (SNPs) and the insertion/Deletion (I/D)-polymorphism in the ACE gene region and investigated their associations with coping styles. In healthy subjects, the highest association was observed between rs8066276, an intronic SNP of the ACE gene, and the coping factor Distraction. A further intronic SNP rs4305, not in linkage disequilibrium with rs8066276, showed an association with Devaluation/Defense. All associated copying styles can be categorized as potentially stress reducing factors (positive coping). Both SNPs were also found to be associated with positive coping styles in the patient sample; rs8066276 was associated with Devaluation/Defense, and rs4305 showed associations with Control. These results suggest that the ACE gene is involved in the development of coping strategies., (2008 Wiley-Liss, Inc.)