The association of obesity and coronary artery disease genes with response to SSRIs treatment in major depression.

Selective serotonin reuptake inhibitors (SSRIs) are first-line antidepressants for the treatment of major depressive disorder (MDD). However, treatment response during an initial therapeutic trial is often poor and is difficult to predict. Heterogeneity of response to SSRIs in depressed patients is partly driven by co-occurring somatic disorders such as coronary artery disease (CAD) and obesity. CAD and obesity may also be associated with metabolic side effects of SSRIs. In this study, we assessed the association of CAD and obesity with treatment response to SSRIs in patients with MDD using a polygenic score (PGS) approach. Additionally, we performed cross-trait meta-analyses to pinpoint genetic variants underpinnings the relationship of CAD and obesity with SSRIs treatment response. First, PGSs were calculated at different p value thresholds (PT) for obesity and CAD. Next, binary logistic regression was applied to evaluate the association of the PGSs to SSRIs treatment response in a discovery sample (ISPC, N = 865), and in a replication cohort (STAR*D, N = 1,878). Finally, a cross-trait GWAS meta-analysis was performed by combining summary statistics. We show that the PGSs for CAD and obesity were inversely associated with SSRIs treatment response. At the most significant thresholds, the PGS for CAD and body mass index accounted 1.3%, and 0.8% of the observed variability in treatment response to SSRIs, respectively. In the cross-trait meta-analyses, we identified (1) 14 genetic loci (including NEGR1, CADM2, PMAIP1, PARK2) that are associated with both obesity and SSRIs treatment response; (2) five genetic loci (LINC01412, PHACTR1, CDKN2B, ATXN2, KCNE2) with effects on CAD and SSRIs treatment response. Our findings implicate that the genetic variants of CAD and obesity are linked to SSRIs treatment response in MDD. A better SSRIs treatment response might be achieved through a stratified allocation of treatment for MDD patients with a genetic risk for obesity or CAD.

Validation of the 17-item Hamilton Depression Rating Scale definition of response for adults with major depressive disorder using equipercentile linking to Clinical Global Impression scale ratings: analysis of Pharmacogenomic Research Network Antidepressant Medication Pharmacogenomic Study (PGRN-AMPS) data.

OBJECTIVE: The study aimed to define thresholds of clinically significant change in 17-item Hamilton Depression Rating Scale (HDRS-17) scores using the Clinical Global Impression-Improvement (CGI-I) Scale as a gold standard. METHODS: We conducted a secondary analysis of individual patient data from the Pharmacogenomic Research Network Antidepressant Medication Pharmacogenomic Study, an 8-week, single-arm clinical trial of citalopram or escitalopram treatment of adults with major depression. We used equipercentile linking to identify levels of absolute and percent change in HDRS-17 scores that equated with scores on the CGI-I at 4 and 8 weeks. Additional analyses equated changes in the HDRS-7 and Bech-6 scale scores with CGI-I scores. RESULTS: A CGI-I score of 2 (much improved) corresponded to an absolute decrease (improvement) in HDRS-17 total score of 11 points and a percent decrease of 50-57%, from baseline values. Similar results were observed for percent change in HDRS-7 and Bech-6 scores. Larger absolute (but not percent) decreases in HDRS-17 scores equated with CGI-I scores of 2 in persons with higher baseline depression severity. CONCLUSIONS: Our results support the consensus definition of response based on HDRS-17 scores (>50% decrease from baseline). A similar definition of response may apply to the HDRS-7 and Bech-6. Copyright © 2016 John Wiley & Sons, Ltd.

Treatment outcomes of depression: the pharmacogenomic research network antidepressant medication pharmacogenomic study.

BACKGROUND: The effectiveness of selective serotonin reuptake inhibitors (SSRIs) in patients with major depressive disorder (MDD) is controversial. AIMS: The clinical outcomes of subjects with nonpsychotic MDD were reported and compared with the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study outcomes to provide guidance on the effectiveness of SSRIs. METHODS: Subjects were treated with citalopram/escitalopram for up to 8 weeks. Depression was measured using the Quick Inventory of Depressive Symptomatology-Clinician Rated (QIDS-C16) and the 17-item Hamilton Depression Rating Scale. RESULTS: The group of subjects with at least 1 follow-up visit had a remission (QIDS-C16 ≤ 5) rate of 45.8% as well as a response (50% reduction in QIDS-C16) rate of 64.8%, and 79.9% achieved an improvement of 5 points or higher in QIDS-C16 score. The Pharmacogenomic Research Network Antidepressant Medication Pharmacogenomic Study subjects were more likely to achieve a response than STAR*D study subjects. After adjustment for demographic factors, the response rates were not significantly different. When reporting the adverse effect burden, 60.5% of the subjects reported no impairment, 31.7% reported a minimal-to-mild impairment, and 7.8% reported a moderate-to-severe burden at the 4-week visit. CONCLUSIONS: Patients contemplating initiating an SSRI to treat their MDD can anticipate a high probability of symptom improvement (79.9%) with a low probability that their symptoms will become worse. Patients with lower baseline severity have a higher probability of achieving remission. The Pharmacogenomic Research Network Antidepressant Medication Pharmacogenomic Study replicates many findings of the first phase of the STAR*D study after controlling for the differences between the studies.

Association of GATA4 sequence variation with alcohol dependence.

To further explore reports of association of alcohol dependence and response to acamprosate treatment with the GATA4 rs13273672 single nucleotide polymorphism (SNP), we genotyped this and 10 other GATA4 SNPs in 816 alcohol-dependent cases and 1248 controls. We tested for association of alcohol dependence with the 11 SNPs individually and performed a global test for association using a principle components analysis. Our analyses demonstrate significant association between GATA4 and alcohol dependence at the gene level (P = 0.009) but no association with rs13273672. Further studies are needed to identify potential causal GATA4 variation(s) and the functional mechanism(s) contributing to this association.

Therapeutic Content of Mobile Phone Applications for Substance Use Disorders: An Umbrella Review.

Mobile phone applications (MPAs) for substance use disorder (SUD) treatment are increasingly used by patients. Although pilot studies have shown promising results, multiple previous systematic reviews noted insufficient evidence for MPA use in SUD treatment-many of the previously published reviews evaluated different trials. Subsequently, we aimed to conduct an umbrella review of previously published reviews investigating the efficacy of MPAs for SUD treatment, excluding nicotine/tobacco because umbrella reviews have been done in this population and the nicotine/tobacco MPA approach often differs from SUD-focused MPAs. No previous reviews have included a statistical meta-analysis of clinical trials to quantify an estimated overall effect. Seven reviews met inclusion criteria, and 17 unique studies with available data were taken from those reviews for the meta-analysis. Overall, reviews reported a lack of evidence for recommending MPAs for SUD treatment. However, MPA-delivered recovery support services, cognitive behavioral therapy, and contingency management were identified across multiple reviews as having promising evidence for SUD treatment. Hedges g effect size for an MPA reduction in substance use-related outcomes relative to the control arm was insignificant (0.137; 95% CI, -0.056 to 0.330; P=.16). In subgroup analysis, contingency management (1.29; 95% CI, 1.088-1.482; τ 2=0; k=2) and cognitive behavioral therapy (0.02; 95% CI, 0.001-0.030; τ 2=0; k=2) were significant. Although contingency management's effect was large, both trials were small (samples of 40 and 30). This review includes an adapted framework for the American Psychiatric Association's MPA guidelines that clinicians can implement to review MPAs critically with patients.

Utility of integrated pharmacogenomic testing to support the treatment of major depressive disorder in a psychiatric outpatient setting.

OBJECTIVE: The objective was to evaluate the potential benefit of an integrated, five-gene pharmacogenomic test and interpretive report (GeneSight) for the management of psychotropic medications used to treat major depression in an outpatient psychiatric practice. METHODS: The open-label study was divided into two groups. In the first (unguided) group (n = 113), pharmacogenomic information was not shared until all participants completed the study. In the second (guided) group (n = 114), the pharmacogenomic report was provided to physicians for clinical use. Three depression ratings, the 17-item Hamilton Rating Scale for Depression (HAMD-17), the Quick Inventory of Depressive Symptomatology - Clinician Rated (QIDS-C16), and the Patient Health Questionnaire (PHQ-9), were collected at baseline, and at 2, 4, and 8 weeks. RESULTS: The guided group experienced greater percent improvement in depression scores from baseline on all three depression instruments (HAMD-17, P < 0.0001; QIDS-C16, P < 0.0001; PHQ-9, P < 0.0001) compared with the unguided group. Eight-week response rates were higher in the guided group than in the unguided group on all three measurements (HAMD-17, P = 0.03; QIDS-C16, P = 0.005; PHQ-9, P = 0.01). Eight-week QIDS-C16 remission rates were higher in the guided group (P = 0.03). Participants in the unguided group who at baseline were prescribed a medication that was most discordant with their genotype experienced the least improvement compared with other unguided participants (HAMD-17, P = 0.007). Participants in the guided group and on a baseline medication most discordant with their genotype showed the greatest improvement compared with the unguided cohort participants (HAMD-17, P = 0.01). CONCLUSION: These findings replicate previous studies and demonstrate significantly improved depression outcomes with use of GeneSight, an integrated, multigenetic pharmacogenomic testing platform.

Association of the PDYN gene with alcohol dependence and the propensity to drink in negative emotional states.

Synthetic κ-opioid receptor (KOR) agonists induce dysphoric and pro-depressive effects and variations in the KOR (OPRK1) and prodynorphin (PDYN) genes have been shown to be associated with alcohol dependence. We genotyped 23 single nucleotide polymorphisms (SNPs) in the PDYN and OPRK1 genes in 816 alcohol-dependent subjects and investigated their association with: (1) negative craving measured by a subscale of the Inventory of Drug Taking Situations; (2) a self-reported history of depression; (3) the intensity of depressive symptoms measured by the Beck Depression Inventory-II. In addition, 13 of the 23 PDYN and OPRK1 SNPs, which were previously genotyped in a set of 1248 controls, were used to evaluate association with alcohol dependence. SNP and haplotype tests of association were performed. Analysis of a haplotype spanning the PDYN gene (rs6045784, rs910080, rs2235751, rs2281285) revealed significant association with alcohol dependence (p = 0.00079) and with negative craving (p = 0.0499). A candidate haplotype containing the PDYN rs2281285-rs1997794 SNPs that was previously associated with alcohol dependence was also associated with negative craving (p = 0.024) and alcohol dependence (p = 0.0008) in this study. A trend for association between depression severity and PDYN variation was detected. No associations of OPRK1 gene variation with alcohol dependence or other studied phenotypes were found. These findings support the hypothesis that sequence variation in the PDYN gene contributes to both alcohol dependence and the induction of negative craving in alcohol-dependent subjects.

A retrospective study of gender differences in depressive symptoms and risk of relapse in patients with alcohol dependence.

BACKGROUND AND OBJECTIVES: The aim of this study was to investigate potential gender differences in situations associated with heavy alcohol drinking. METHODS: Data from 395 alcohol dependent patients participating in the Mayo Clinic Intensive Addiction Program were evaluated. Each participant completed the inventory of drug taking situations (IDTS), Penn alcohol craving scale (PACS), patient health questionnaire (PHQ-9), and/or Beck depression inventory (BDI). Gender differences in IDTS scores representing three domains (negative, positive, and temptation) of situations associated with heavy alcohol use were examined. RESULTS: Women with alcohol dependence report a higher frequency of heavy drinking in unpleasant emotional (IDTS negative scores mean ± SD women vs. men: 52.3 ± 22.1 vs. 43.8 ± 21.8; p = .0006), and as a result of temptation (IDTS temptation scores mean ± SD women vs. men: 40.4 ± 23.0 vs. 35.3 ± 20.8; p = .035). Upon admission, women also scored significantly higher on depressive symptoms as measured by the BDI (23.4 ± 11.4 vs. 18.2 ± 9.8, p < .001). After controlling for depressive symptom severity as a covariate, the IDTS gender differences were no longer significant. CONCLUSION AND SCIENTIFIC SIGNIFICANCE: Our results suggest that unpleasant or temptation based emotional situations are a vulnerability risk factor for heavy drinking particularly in females. This risk appears to be at least partially driven by depressive symptom burden. Future research is needed to further investigate this finding.

Alcohol craving as a predictor of relapse.

BACKGROUND AND OBJECTIVES: Alcoholism treatment interventions, both psychosocial and pharmacologic, aim to reduce cravings to drink. Yet, the role of craving in treatment outcomes remains unclear. This study evaluated craving intensity measured with the Penn Alcohol Craving Scale (PACS) at admission and discharge from residential treatment as a predictive factor of relapse after treatment. METHODS: The study cohort included 314 alcohol-dependent subjects. Associations between relapse after discharge, PACS score, and clinical variables were investigated using time-to-event analyses. The primary analysis, based on the intent-to-treat principle, presumed relapse in those declining follow-up or not responding to contact attempts. Secondary analysis utilized data from 226 subjects successfully contacted after discharge with a median follow-up time of 365 days. RESULTS: The intent-to-treat analysis demonstrated that relapse was associated with higher level of craving at admission (p= .002) and discharge (p < .001). The analysis of data from patients successfully contacted after discharge led to similar results. A multivariable analysis indicated that relapse rates increased as PACS scores increased, and a higher discharge PACS score was significantly associated with relapse (p= .006) even after adjusting for covariates. CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE: This study demonstrates that higher PACS scores at the time of admission and discharge are associated with relapse following residential addiction treatment. These data support the role of craving in relapse and the utility of craving measurement as a clinical guide in assessing relapse risk.

Trazodone and alcohol relapse: a retrospective study following residential treatment.

Trazodone is one of the most commonly prescribed hypnotic medications in patients with sleep disturbances in alcohol recovery. A recent study concluded that treating insomnia with trazodone in patients with alcohol dependence might impede improvements in alcohol consumption and lead to increased drinking when trazodone is stopped. We set out to investigate the relationship between trazodone use during alcoholism treatment and relapse rates in patients who were discharged from a residential alcohol treatment program. We retrospectively reviewed records of patients with a diagnosis of alcohol dependence in a residential addiction treatment center from 2005 to 2008 and analyzed the association of trazodone use at discharge and alcohol relapse at 6 months. We also assessed the association between trazodone use and relapse at 6 months adjusting for sex, drug dependence, nonsubstance use Axis I psychiatric diagnoses, patient self-report of difficulties with sleep, and anti-dipsotropic medication use at discharge and evaluated pair-wise interactions of trazodone use with the adjustment variables. Of 283 patients eligible for inclusion, 85 (30%) were taking trazodone at discharge. Older age, self-reported sleep problems, and having a nonsubstance use Axis I psychiatric diagnosis were associated with trazodone use. After discharge, 170 (60%) subjects responded to follow-up efforts. Neither intent to treat nor responder only analysis revealed any association between trazodone use and relapse. Our retrospective study of a complex patient population discharged from a residential treatment setting did not find an association between trazodone use at discharge and relapse rates at 6 months.

Utilization of residential alcoholism treatment in bipolar disorder.

Despite the high prevalence rate of comorbid alcohol dependence and bipolar disorder, little is known about how many bipolar patients are actively engaged in addiction treatment or the alcohol consumption characteristics of this group. This retrospective study reviewed the medical records from patients with alcohol dependence admitted to residential treatment at our institution (n = 588). The analyses focused on alcoholism severity measures and discharge clinical diagnoses. Patients with alcoholism + bipolar disorder compromised only 5% of the total study group. The number of drinking years was lower for patients with alcoholism + bipolar disorder (23.1 ± 17.7) than for those with alcoholism + depression (26.8 ± 13.9) or alcoholism alone (28.1 ± 13.2). A trend of higher mean lifetime maximum daily drinks was observed for patients with alcoholism + bipolar disorder; this was because of the significantly higher maximum drinks for women with bipolar disorder (21.0 ± 11.5) than for women in other diagnostic groups. Despite high rates of comorbidity in community-based studies, this retrospective study suggests that patients with bipolar disorder are not highly represented in residential alcoholism addiction treatment. Future studies are encouraged to better understand utilization rates of addiction treatment among patients with bipolar disorder and to identify clinical correlates that predispose bipolar women to high-dose drinking.

Telling the patient's story: using theatre training to improve case presentation skills.

A medical student's ability to present a case history is a critical skill that is difficult to teach. Case histories presented without theatrical engagement may fail to catch the attention of their intended recipients. More engaging presentations incorporate 'stage presence', eye contact, vocal inflection, interesting detail and succinct, well organised performances. They convey stories effectively without wasting time. To address the didactic challenge for instructing future doctors in how to 'act', the Mayo Medical School and The Mayo Clinic Center for Humanities in Medicine partnered with the Guthrie Theater to pilot the programme 'Telling the Patient's Story'. Guthrie teaching artists taught storytelling skills to medical students through improvisation, writing, movement and acting exercises. Mayo Clinic doctors participated and provided students with feedback on presentations and stories from their own experiences in patient care. The course's primary objective was to build students' confidence and expertise in storytelling. These skills were then applied to presenting cases and communicating with patients in a fresher, more engaging way. This paper outlines the instructional activities as aligned with course objectives. Progress was tracked by comparing pre-course and post-course surveys from the seven participating students. All agreed that the theatrical techniques were effective teaching methods. Moreover, this project can serve as an innovative model for how arts and humanities professionals can be incorporated for teaching and professional development initiatives at all levels of medical education.

Factors Having an Impact on Relapse and Survival in Transplant Recipients With Alcohol-Induced Liver Disease.

OBJECTIVE: To assess the impact of standardized pretransplant alcohol abstinence and treatment guidelines on liver transplant outcomes. METHODS: This study assessed the posttransplant relapse and survival associated with a pretransplant guideline mandating alcohol abstinence, addiction treatment, and Alcoholics Anonymous (AA) attendance. This retrospective cohort study included liver recipients with alcohol-induced liver disease transplanted between January 1, 2000, and December 31, 2012, at a Midwest transplant center. Cox regression models tested for associations between pretransplant treatment, demographic and clinical characteristics, and outcome measures. RESULTS: Of 236 liver recipients (188 [79.7%] male; 210 [89%] white; mean follow-up, 88.6±55.0 months), 212 (90.2%) completed pretransplant treatment and 135 (57.2%) attended AA weekly. At 5 years, 16.3% and 8.2% had relapsed to any alcohol use and to high-dose drinking, respectively. Smoking during the 6 months before transplant was associated with any relapse (P=.0002) and high-dose relapse (P<.0001), and smoking at transplant was associated with death (P=.001). High-dose relapse was associated with death (hazard ratio, 3.5; P<.0001). CONCLUSION: A transplant center with a guideline requiring abstinence, treatment, and AA participation experienced lower posttransplant relapse rates from those previously reported in comparable large US transplant programs. Smoking cessation may further improve posttransplant outcomes.

Substance Use Disorders and Telehealth in the COVID-19 Pandemic Era: A New Outlook.

During the current coronavirus disease 2019 epidemic, many outpatient chemical dependency treatment programs and clinics are decreasing their number of in-person patient contacts. This has widened an already large gap between patients with substance use disorders (SUDs) who need treatment and those who have actually received treatment. For a disorder where group therapy has been the mainstay treatment option for decades, social distancing, shelter in place, and treatment discontinuation have created an urgent need for alternative approaches to addiction treatment. In an attempt to continue some care for patients in need, many medical institutions have transitioned to a virtual environment to promote safe social distancing. Although there is ample evidence to support telemedical interventions, these can be difficult to implement, especially in the SUD population. This article reviews current literature for the use of telehealth interventions in the treatment of SUDs and offers recommendations on safe and effective implementation strategies based on the current literature.

Cannabis abuse and dependence in kidney transplant candidates.

OBJECTIVE: Cannabis is the most commonly used non-alcohol intoxicant in the general population. There are no consistent guidelines on the implications of cannabis abuse and dependence (CAD) in kidney transplant candidates. The aims of this study were to characterize kidney transplant candidates with comorbid CAD and examine the implications of CAD on transplant candidacy. METHOD: This was a retrospective cohort study of kidney transplant candidates meeting diagnostic criteria for CAD at a tertiary center from 2012 to 2016. Candidates were reviewed for psychiatric and substance use disorders (SUDs), family history, and medical variables. The cohort was divided by severity of CAD and transplant listing status for comparisons. Statistical analysis included Kruskal-Wallis tests for continuous variables and Fisher's Exact Test for categorical variables. RESULTS: Sixty-one of 2067 (3%) kidney transplant candidates met criteria for CAD, and 13/61 (21%) underwent transplantation. Of 61, 58% smoked cannabis daily, 47% had alcohol dependence history, 31% had other illicit drug dependencies, 38% were smokers, 60% had a SUD family history, and 42% and 27% had depressive and anxiety disorders, respectively. Severity of CAD was inversely associated with transplant listing; those with cannabis abuse were more often listed than those with dependence (67% vs 33%, p = .02) by study end. Three case presentations illustrate cannabis-related issues. CONCLUSION: In this cohort, kidney transplant candidates with comorbid CAD have high prevalence of other substance use disorders, psychiatric comorbidities, and strong family histories of addictions that resemble other SUD populations. These findings have implications for pre-transplant screening and treatment and post-transplant monitoring.

Sex-specific association of depressive disorder and transient emotional states with alcohol consumption in male and female alcoholics.

BACKGROUND: We assessed the impact of comorbid depression and anxiety disorders as well as positive and negative emotional states on alcohol consumption in alcohol dependent men and women. METHODS: Per day alcohol consumption during 90 days before enrolment was assessed by the Time Line Follow Back (TLFB) in 287 men and 156 women meeting DSM-IV-TR criteria for alcohol dependence. Propensity to drink in negative/positive emotional states was assessed using the Inventory of Drug Taking Situations (IDTS). Psychiatric comorbidities, including major depressive disorder (MDD), substance-induced depression (SID), anxiety disorders (AnxD), or substance-induced anxiety (SIA) were identified by Psychiatric Research Interview of Substance and Mood Disorders (PRISM). RESULTS: In the combined group, increased number of drinks per day and number of heavy drinking days correlated with increased IDTS scores (all p < 0.0001), while the lifetime history of MDD was associated with fewer drinking days (p = 0.045) but not average number of drinks per day. Male sex was associated with higher alcohol consumption per day (p < 0.0001), but not with the number of drinking days (p > 0.05). Lifetime MDD history was associated with less drinking days (p = 0.0084) and less heavy drinking days (p = 0.021) in alcohol dependent men, while current MDD was associated with higher alcohol use per day in alcohol dependent women (p = 0.044). CONCLUSIONS: Our findings suggest that emotional states and lifetime MDD history have sex-specific impact on alcohol use in alcohol dependent men and women. The mechanisms underlying these findings and their relevance to treatment outcomes need to be examined in future studies.

Pharmacokinetic-Pharmacodynamic interaction associated with venlafaxine-XR remission in patients with major depressive disorder with history of citalopram / escitalopram treatment failure.

BACKGROUND: The purpose of this study was to identify specific pharmacokinetic (PK) and pharmacodynamics (PD) factors that affect the likelihood of treatment remission with a serotonin norepinephrine reuptake inhibitor (SNRI) in depressed patients whose initial selective serotonin reuptake inhibitor (SSRI) failed. METHODS: Multiple logistic regression modeling of PK and PD variation hypothesized to contribute to SNRI (i.e. duloxetine or venlafaxine) treatment remission in prior SSRI (i.e. citalopram or escitalopram) failure was conducted on 139 subjects from the Pharmacogenomics Research Network (PGRN) and Sequenced Treatment Alternatives to Relieve Depression (STAR*D) studies. Depressive symptoms were assessed with the Quick Inventory of Depressive Symptomatology Clinician-rated (QIDS-C16). RESULTS: Venlafaxine-XR remission was associated with a significant interaction between CYP2D6 ultra-rapid metabolizer (URM) phenotype and SLC6A4 5-HTTLPR L/L genotype. A similar significant interaction effect was observed between CYP2D6 URM and SLC6A2 G1287A GA genotype. Stratifying by transporter genotypes, venlafaxine-XR remission was associated with CYP2D6 URM in patients with SLC6A4 L/L (p = 0.001) and SLC6A2 G1287A GA genotypes. LIMITATIONS: The primary limitation of this post hoc study was small sample size. CONCLUSION: Our results suggest that CYP2D6 ultra-rapid metabolizer status contributes to venlafaxine-XR treatment remission in MDD patients; in particular, there is a PK-PD interaction with treatment remission associated with CYP2D6 URM phenotype and SLC6A4 5-HTTLPR L/L or SLC6A2 G1287A G/A genotype, respectively. These preliminary data are encouraging and support larger pharmacogenomics studies differentiating treatment response to mechanistically different antidepressants in addition to further PK-PD interactive analyses.

Beta-defensin 1, aryl hydrocarbon receptor and plasma kynurenine in major depressive disorder: metabolomics-informed genomics.

Major depressive disorder (MDD) is a heterogeneous disease. Efforts to identify biomarkers for sub-classifying MDD and antidepressant therapy by genome-wide association studies (GWAS) alone have generally yielded disappointing results. We applied a metabolomics-informed genomic research strategy to study the contribution of genetic variation to MDD pathophysiology by assaying 31 metabolites, including compounds from the tryptophan, tyrosine, and purine pathways, in plasma samples from 290 MDD patients. Associations of metabolite concentrations with depressive symptoms were determined, followed by GWAS for selected metabolites and functional validation studies of the genes identified. Kynurenine (KYN), the baseline plasma metabolite that was most highly associated with depressive symptoms, was negatively correlated with severity of those symptoms. GWAS for baseline plasma KYN concentrations identified SNPs across the beta-defensin 1 (DEFB1) and aryl hydrocarbon receptor (AHR) genes that were cis-expression quantitative trait loci (eQTLs) for DEFB1 and AHR mRNA expression, respectively. Furthermore, the DEFB1 locus was associated with severity of MDD symptoms in a larger cohort of 803 MDD patients. Functional studies demonstrated that DEFB1 could neutralize lipopolysaccharide-stimulated expression of KYN-biosynthesizing enzymes in monocytic cells, resulting in altered KYN concentrations in the culture media. In addition, we demonstrated that AHR was involved in regulating the expression of enzymes in the KYN pathway and altered KYN biosynthesis in cell lines of hepatocyte and astrocyte origin. In conclusion, these studies identified SNPs that were cis-eQTLs for DEFB1 and AHR and, which were associated with variation in plasma KYN concentrations that were related to severity of MDD symptoms.

Mapping depression rating scale phenotypes onto research domain criteria (RDoC) to inform biological research in mood disorders.

BACKGROUND: Substantial research progress can be achieved if available clinical datasets can be mapped to the National Institute of Mental Health Research-Domain-Criteria (RDoC) constructs. This mapping would allow investigators to both explore more narrowly defined clinical phenotypes and the relationship of these phenotypes to biological markers and clinical outcomes approximating RDoC criteria. METHODS: Using expert review and consensus, we defined four major depression phenotypes based on specific RDoC constructs. Having matched these constructs to individual items from the Hamilton Depression Rating Scale and Quick Inventory of Depressive Symptomatology, we identified subjects meeting criteria for each of these phenotypes from two large clinical trials of patients treated for major depression. In a post hoc analysis, we evaluated the overall treatment response based on the phenotypes: Core Depression (CD), Anxiety (ANX), and Neurovegetative Symptoms of Melancholia (NVSM) and Atypical Depression (NVSAD). RESULTS: The phenotypes were prevalent (range 10.5-52.4%, 50% reduction range 51.9-82.9%) and tracked with overall treatment response. Although the CD phenotype was associated with lower rates of remission in both cohorts, this was mainly driven by baseline symptom severity. However, when controlling for baseline severity, patients with the ANX phenotype had a significantly lower rate of remission. LIMITATIONS: The lack of replication between the studies of the phenotypes' treatment prediction value reflects important variability across studies that may limit generalizability. CONCLUSION: Further work evaluating biological markers associated with these phenotypes is needed for further RDoC concept development.