Citations 89

Elevated Glutamate Levels in the Left Dorsolateral Prefrontal Cortex Are Associated with Higher Cravings for Alcohol

Alcoholism: Clinical and Experimental Research | July 20, 2016 | Volume: 40 | Issue: 8 | Pages: 1609-1616

10.1111/acer.13131 | PMID 27439218

BackgroundQuantifying craving longitudinally during the course of withdrawal, early abstinence, and relapse is essential for optimal management of alcohol use disorder (AUD). In an effort to identify biological correlates of craving, we used proton magnetic resonance spectroscopy (1H‐MRS) to investigate the correlation between craving and glutamate levels in the left dorsolateral prefrontal cortex (LDLPFC) of patients with AUD.MethodsParticipants underwent 1H‐MRS of the LDLPFC with 2‐dimensional J‐resolved (2DJ) averaged PRESS. MRS data were processed with LCModel and cerebrospinal fluid (CSF)‐corrected to generate metabolite concentrations. The Penn Alcohol Craving Scale (PACS) and the 30‐day time line follow‐back (TLFB 30) were used to quantify craving for alcohol and drinking patterns, respectively.ResultsThere was a statistically significant positive correlation between CSF‐corrected glutamate ([Glu]) levels and PACS scores (n = 14; p = 0.005). When PACS scores were dichotomized (< or ≥median = 16), [Glu] levels were significantly higher in the high‐ versus low‐craving group (p = 0.007). In addition, there was a significant negative correlation between CSF‐corrected N‐acetyl aspartic acid ([NAA]) levels and mean number of drinks per drinking day in the past month (n = 13; TLFB 30; p = 0.012). When mean TLFB 30 was dichotomized (< or ≥median = 7.86), [NAA] levels were significantly lower in subjects that consumed more alcoholic beverages. There was no significant correlation between [Glu] and [NAA] levels with other measures of drinking behavior and or depression symptom severity.ConclusionsWhile limited by small sample size, these data suggest that glutamate levels in LDLPFC are associated with alcohol craving intensity in patients with AUD. Further study with larger sample size is needed to replicate this finding and evaluate the merits of glutamate spectroscopy as a biological correlate of alcohol craving intensity and a guide to treatment interventions.
Gender‐specific effects of comorbid depression and anxiety on the propensity to drink in negative emotional states

Addiction | March 24, 2016 | Volume: 111 | Issue: 8 | Pages: 1366-1375

10.1111/add.13386 | PMID 27009547

Abstract Background and Aims Depression and anxiety are often comorbid with alcoholism and contribute to craving and relapse. We aimed to estimate the prevalence of life‐time diagnoses of major depressive disorder (MDD), substance‐induced depression (SID), anxiety disorder (AnxD) and substance‐induced anxiety (SIA), the effects of these comorbidities on the propensity to drink in negative emotional states (negative craving), and test whether these effects differ by sex. Design Secondary analyses of baseline data collected in a single‐arm study of pharmacogenetic predictors of acamprosate response. Setting Academic medical center and affiliated community‐based treatment programs in the American upper mid‐west. Participants A total of 287 males and 156 females aged 18–80 years, meeting DSM‐IV criteria for alcohol dependence. Measurements The primary outcome measure was ‘propensity to drink in negative emotional situations’ (determined by the Inventory of Drug Taking Situations) and the key predictors/covariates were sex and psychiatric comorbidities, including MDD, SID, AnxD and SIA (determined by Psychiatric Research Interview of Substance and Mood Disorders). Findings The prevalence of the MDD, SID and AnxD was higher in females compared with males (33.1 versus 18.4%, 44.8 versus 26.4% and 42.2 versus 27.4%, respectively; P < 0.01, each), while SIA was rare (3.3%) and did not differ by sex. Increased propensity to drink in negative emotional situations was associated with comorbid MDD (β = 6.6, P = 0.013) and AnxD (β = 4.8, P = 0.042) as well as a SID × sex interaction effect ( P = 0.003), indicating that the association of SID with propensity to drink in negative emotional situations differs by sex and is stronger in males (β = 7.9, P = 0.009) compared with females (β = −6.6, P = 0.091). Conclusions There appears to be a higher prevalence of comorbid depression and anxiety disorders as well as propensity to drink in negative emotional situations in female compared with male alcoholics. Substance‐induced depression appears to have a sex‐specific effect on the increased risk for drinking in negative emotional situations in males.
Validation of the 17‐item Hamilton Depression Rating Scale definition of response for adults with major depressive disorder using equipercentile linking to Clinical Global Impressi

Human Psychopharmacology: Clinical and Experimental | March 21, 2016 | Volume: 31 | Issue: 3 | Pages: 185-192

10.1002/hup.2526 | PMID 26999588

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.
Accumulating evidence for a role of TCF7L2 variants in bipolar disorder with elevated body mass index

Bipolar Disorders | March 2, 2016 | Volume: 18 | Issue: 2 | Pages: 124-135

10.1111/bdi.12368 | PMID 26934194

ObjectivesBipolar disorder (BD) is a complex disease associated with various hereditary traits, including a higher body mass index (BMI). In a prior genome‐wide association study, we found that BMI modified the association of rs12772424 – a common variant in the gene encoding transcription factor 7‐like 2 (TCF7L2) – with risk for BD. TCF7L2 is a transcription factor in the canonical Wnt pathway, involved in multiple disorders, including diabetes, cancer and psychiatric conditions. Here, using an independent sample, we evaluated 26 TCF7L2 single nucleotide polymorphisms (SNPs) to explore further the association of BD with the TCF7L2–BMI interaction.MethodsUsing a sample of 662 BD cases and 616 controls, we conducted SNP‐level and gene‐level tests to assess the evidence for an association between BD and the interaction of BMI and genetic variation in TCF7L2. We also explored the potential mechanism behind the detected associations using human brain expression quantitative trait loci (eQTL) analysis.ResultsThe analysis provided independent evidence of an rs12772424–BMI interaction (p = 0.011). Furthermore, while overall there was no evidence for SNP marginal effects on BD, the TCF7L2–BMI interaction was significant at the gene level (p = 0.042), with seven of the 26 SNPs showing SNP–BMI interaction effects with p < 0.05. The strongest evidence of interaction was observed for rs7895307 (p = 0.006). TCF7L2 expression showed a significant enrichment of association with the expression of other genes in the Wnt canonical pathway.ConclusionsThe current study provides further evidence suggesting that TCF7L2 involvement in BD risk may be regulated by BMI. Detailed, prospective assessment of BMI, comorbidity, and other possible contributing factors is necessary to explain fully the mechanisms underlying this association.
Modeling X Chromosome Data Using Random Forests: Conquering Sex Bias

Genetic Epidemiology | December 8, 2015 | Volume: 40 | Issue: 2 | Pages: 123-132

10.1002/gepi.21946 | PMID 26639183

Pharmacogenomics of estrogens on changes in carotid artery intima-medial thickness and coronary arterial calcification: Kronos Early Estrogen Prevention Study

Physiological Genomics | October 28, 2015 | Volume: 48 | Issue: 1 | Pages: 33-41

10.1152/physiolgenomics.00029.2015 | PMID 26508701

Prior to the initiation of menopausal hormone treatment (MHT), genetic variations in the innate immunity pathway were found to be associated with carotid artery intima-medial thickness (CIMT) and coronary arterial calcification (CAC) in women ( n = 606) enrolled in the Kronos Early Estrogen Prevention Study (KEEPS). Whether MHT might affect these associations is unknown. The association of treatment outcomes with variation in the same 764 candidate genes was evaluated in the same KEEPS participants 4 yr after randomization to either oral conjugated equine estrogens (0.45 mg/day), transdermal 17β-estradiol (50 μg/day), each with progesterone (200 mg/day) for 12 days each month, or placebo pills and patch. Twenty SNPs within the innate immunity pathway most related with CIMT after 4 yr were not among those associated with CIMT prior to MHT. In 403 women who completed the study in their assigned treatment group, single nucleotide polymorphisms (SNPs) within the innate immunity pathway were found to alter the treatment effect on 4 yr change in CIMT (i.e., significant interaction between treatment and genetic variation in the innate immunity pathway; P < 0.001). No SNPs by treatment effects were observed with changes of CAC >5 Agatston units after 4 yr. Results of this study suggest that hormonal status may interact with genetic variants to influence cardiovascular phenotypes, specifically, the pharmacogenomic effects within the innate immunity pathway for CIMT.
Sex differences in the risk of rapid cycling and other indicators of adverse illness course in patients with bipolar I and II disorder

Bipolar Disorders | September 4, 2015 | Volume: 17 | Issue: 6 | Pages: 670-676

10.1111/bdi.12329 | PMID 26529373

ObjectivesTo examine the independent effects of sex on the risk of rapid cycling and other indicators of adverse illness course in patients with bipolar I disorder (BP‐I) or bipolar II disorder (BP‐II).MethodsWe analyzed data from the first 1,225 patients enrolled in the Mayo Clinic Individualized Medicine Biobank for Bipolar Disorder. Demographic and clinical variables were ascertained using standardized questionnaires; height and weight were assessed to determine body mass index (BMI). Rates of rapid cycling, cycle acceleration, and increased severity of mood episodes over time were compared between women and men overall and within subgroups defined by bipolar disorder subtype (BP‐I or BP‐II). Multiple logistic regression analysis was used to assess the independent effect of sex on the risk of these indicators of adverse illness course.ResultsWomen had significantly higher rates of rapid cycling than men. Overall rates of rapid cycling were higher in patients with BP‐II than BP‐I; and sex differences in the rate of rapid cycling were more pronounced in patients with BP‐II than BP‐I, although the power to detect statistically significant differences was reduced due to the lower sample size of subjects with BP‐II. Female sex was a significant predictor of rapid cycling, cycle acceleration, and increased severity of mood episodes over time after adjusting for age, bipolar disorder subtype, BMI, having any comorbid psychiatric disorder, and current antidepressant use.ConclusionsFemale sex was associated with significantly higher risk of rapid cycling, cycle acceleration, and increased severity of mood episodes over time in a sample of 1,225 patients with bipolar disorders.
Association of brain‐derived neurotrophic factor (BDNF) Val66Met polymorphism with early‐onset bipolar disorder

Bipolar Disorders | September 4, 2015 | Volume: 17 | Issue: 6 | Pages: 645-652

10.1111/bdi.12323 | PMID 26528762

ObjectivesBrain‐derived neurotrophic factor (BDNF) Val66Met (rs6265) functional polymorphism has been implicated in early‐onset bipolar disorder. However, results of studies are inconsistent. We aimed to further explore this association.MethodsDNA samples from the Treatment of Early Age Mania (TEAM) and Mayo Clinic Bipolar Disorder Biobank were investigated for association of rs6265 with early‐onset bipolar disorder. Bipolar cases were classified as early onset if the first manic or depressive episode occurred at age ≤19 years (versus adult‐onset cases at age >19 years). After quality control, 69 TEAM early‐onset bipolar disorder cases, 725 Mayo Clinic bipolar disorder cases (including 189 early‐onset cases), and 764 controls were included in the analysis of association, assessed with logistic regression assuming log‐additive allele effects.ResultsComparison of TEAM cases with controls suggested association of early‐onset bipolar disorder with the rs6265 minor allele [odds ratio (OR) = 1.55, p = 0.04]. Although comparison of early‐onset adult bipolar disorder cases from the Mayo Clinic versus controls was not statistically significant, the OR estimate indicated the same direction of effect (OR = 1.21, p = 0.19). When the early‐onset TEAM and Mayo Clinic early‐onset adult groups were combined and compared with the control group, the association of the minor allele rs6265 was statistically significant (OR = 1.30, p = 0.04).ConclusionsThese preliminary analyses of a relatively small sample with early‐onset bipolar disorder are suggestive that functional variation in BDNF is implicated in bipolar disorder risk and may have a more significant role in early‐onset expression of the disorder.
National Survey and Community Advisory Board Development for a Bipolar Disorder Biobank

Bipolar Disorders | August 20, 2015 | Volume: 17 | Issue: 6 | Pages: 598-605

10.1111/bdi.12322 | PMID 26291791

ObjectivesThe aim of the present study was to engage a national advocacy group and local stakeholders for guidance in developing a bipolar disorder biobank through a web‐based survey and a community advisory board.MethodsThe Depression and Bipolar Support Alliance and the Mayo Clinic Bipolar Biobank conducted a national web‐based survey inquiring about interest in participating in a biobank (i.e., giving DNA and clinical information). A community advisory board was convened to guide establishment of the biobank and identify key deliverables from the research project and for the community.ResultsAmong 385 survey respondents, funding source (87%), professional opinion (76%), mental health consumer opinion (79%), and return of research results (91%) were believed to be important for considering study participation. Significantly more patients were willing to participate in a biobank managed by a university or clinic (78.2%) than one managed by government (63.4%) or industry (58.2%; both p < 0.001). The nine‐member community advisory board expressed interest in research to help predict the likelihood of bipolar disorder developing in a child of an affected parent and which medications to avoid. The advisory board endorsed the use of a comprehension questionnaire to evaluate participants' understanding of the study (e.g., longevity of DNA specimens, right to remove samples, accessing medical records) as a means to strengthen the informed consent process.ConclusionsThese national survey and community advisory data support the merit of establishing a biobank to enable studies of disease risk, provided that health records and research results are adequately protected. The goals of earlier diagnosis and individualized treatment of bipolar disorder were endorsed.
Association between history of psychosis and cardiovascular disease in bipolar disorder

Bipolar Disorders | June 11, 2015 | Volume: 17 | Issue: 5 | Pages: 518-527

10.1111/bdi.12302 | PMID 26062406

ObjectivesTo determine whether clinical features of bipolar disorder, such as history of psychosis, and cardiovascular disease (CVD) risk factors contribute to a higher risk of CVD among patients with bipolar disorder.MethodsThis cross‐sectional study included a sample of 988 patients with bipolar I or bipolar II disorder or schizoaffective bipolar type confirmed by the Structured Clinical Interview for DSM‐IV‐TR disorders (SCID). Medical comorbidity burden was quantified utilizing the Cumulative Illness Severity Rating Scale (CIRS). This 13‐item organ‐based scale includes cardiac disease severity quantification. Confirmed by medical record review, patients who scored 1 (current mild or past significant problem) or higher in the cardiac item were compared by logistic regression to patients who scored 0 (no impairment), adjusting for CVD risk factors that were selected using a backwards stepwise approach or were obtained from the literature.ResultsIn a multivariate model, age [odds ratio (OR) = 3.03, 95% confidence interval (CI): 1.66–5.54, p < 0.0001], hypertension (OR = 2.43, 95% CI: 1.69–3.55, p < 0.0001), and history of psychosis (OR = 1.48, 95% CI: 1.03–2.13, p = 0.03) were associated with CVD. When CVD risk factors from the literature were added to the analysis, age (OR = 3.19, 95% CI: 1.67–6.10, p = 0.0005) and hypertension (OR = 2.46, 95% CI: 1.61–3.76, p < 0.01) remained significant, with psychosis being at the trend level (OR = 1.43, 95% CI: 0.96–2.13, p = 0.08).ConclusionsThe phenotype of psychotic bipolar disorder may reflect higher illness severity with associated cardiac comorbidity. Further studies are encouraged to clarify the effect of the disease burden (i.e., depression), lifestyle, and treatment interventions (i.e., atypical antipsychotics) on this risk association.