Laura Thornton | University of North Carolina at Chapel Hill (original) (raw)

Papers by Laura Thornton

Contemporary Clinical Trials Communications

Contemporary clinical trials, 2018

Genetic factors contribute to anorexia nervosa (AN); and the first genome-wide significant locus ... more Genetic factors contribute to anorexia nervosa (AN); and the first genome-wide significant locus has been identified. We describe methods and procedures for the Anorexia Nervosa Genetics Initiative (ANGI), an international collaboration designed to rapidly recruit 13,000 individuals with AN and ancestrally matched controls. We present sample characteristics and the utility of an online eating disorder diagnostic questionnaire suitable for large-scale genetic and population research. ANGI recruited from the United States (US), Australia/New Zealand (ANZ), Sweden (SE), and Denmark (DK). Recruitment was via national registers (SE, DK); treatment centers (US, ANZ, SE, DK); and social and traditional media (US, ANZ, SE). All cases had a lifetime AN diagnosis based on DSM-IV or ICD-10 criteria (excluding amenorrhea). Recruited controls had no lifetime history of disordered eating behaviors. To assess the positive and negative predictive validity of the online eating disorder questionnaire...

European eating disorders review : the journal of the Eating Disorders Association, Jan 22, 2018

Anorexia nervosa (AN) and obsessive-compulsive disorder (OCD) are highly comorbid. However, the f... more Anorexia nervosa (AN) and obsessive-compulsive disorder (OCD) are highly comorbid. However, the factors that account for this comorbidity are poorly understood. We examined the core dimensions of AN and OCD and psychological and personality factors shared by both disorders. In path analyses (N = 732 women with either current AN or recovered from AN), we examined which factors were uniquely and independently associated with the core dimensions of AN and OCD. We also examined recovery from AN as a moderator. When individuals with AN reported greater concern over mistakes, they endorsed more severity in both AN and OCD core dimensions. These unique associations existed above and beyond all other transdiagnostic personality and psychological factors and regardless of AN recovery status. Concern over mistakes partially accounts for severity in the core dimensions of both AN and OCD. Concern over mistakes may represent an important target in the aetiology of AN and OCD.

Molecular psychiatry, Jan 7, 2018

Anorexia nervosa (AN) and obsessive-compulsive disorder (OCD) are often comorbid and likely to sh... more Anorexia nervosa (AN) and obsessive-compulsive disorder (OCD) are often comorbid and likely to share genetic risk factors. Hence, we examine their shared genetic background using a cross-disorder GWAS meta-analysis of 3495 AN cases, 2688 OCD cases, and 18,013 controls. We confirmed a high genetic correlation between AN and OCD (r = 0.49 ± 0.13, p = 9.07 × 10) and a sizable SNP heritability (SNP h = 0.21 ± 0.02) for the cross-disorder phenotype. Although no individual loci reached genome-wide significance, the cross-disorder phenotype showed strong positive genetic correlations with other psychiatric phenotypes (e.g., r = 0.36 with bipolar disorder and 0.34 with neuroticism) and negative genetic correlations with metabolic phenotypes (e.g., r = -0.25 with body mass index and -0.20 with triglycerides). Follow-up analyses revealed that although AN and OCD overlap heavily in their shared risk with other psychiatric phenotypes, the relationship with metabolic and anthropometric traits is...

The International journal of eating disorders, 2017

Previous studies evaluating the association between early childhood adversities and eating disord... more Previous studies evaluating the association between early childhood adversities and eating disorders have yielded conflicting results. The aim of this study is to examine the association between a range of adversities and risk of anorexia nervosa (AN), bulimia nervosa (BN), and eating disorder not otherwise specified (EDNOS) in 495,244 women. In this nationwide, register-based cohort study, nine types of early childhood adversity (family disruption, residential instability, placement in out-of-home care, familial death, parental somatic illness, parental psychiatric illness, parental disability, severe parental criminality, and parental substance use disorder) were defined and exposure during the first 6 years of life was determined. Hazard ratios for eating disorders were calculated using Cox regression. Few adversities were significantly associated with AN, and for each, the presence of the adversity was associated with lower risk for AN. BN, and EDNOS were positively associated w...

Pediatrics, 2017

Identifying factors associated with risk for eating disorders is important for clarifying etiolog... more Identifying factors associated with risk for eating disorders is important for clarifying etiology and for enhancing early detection of eating disorders in primary care. We hypothesized that autoimmune and autoinflammatory diseases would be associated with eating disorders in children and adolescents and that family history of these illnesses would be associated with eating disorders in probands. In this large, nationwide, population-based cohort study of all children and adolescents born in Denmark between 1989 and 2006 and managed until 2012, Danish medical registers captured all inpatient and outpatient diagnoses of eating disorders and autoimmune and autoinflammatory diseases. The study population included 930 977 individuals (48.7% girls). Cox proportional hazards regression models and logistic regression were applied to evaluate associations. We found significantly higher hazards of eating disorders for children and adolescents with autoimmune or autoinflammatory diseases: 36%...

The International journal of eating disorders, 2017

We examined epidemiological associations between anorexia nervosa (AN) and bulimia nervosa (BN) a... more We examined epidemiological associations between anorexia nervosa (AN) and bulimia nervosa (BN) and risks of committing theft and other crimes in a nationwide female population. Females born in Sweden during 1979-1998 (N = 957,106) were followed from age 15 for up to 20 years using information on clinically diagnosed AN and BN (exposures), convictions of theft and other crimes (outcomes), psychiatric comorbidities, and familial relatedness from Swedish national registers. We estimated hazard ratios (HRs) of criminality in exposed versus unexposed females using Cox proportional hazards regressions and explored how comorbidities and unmeasured familial factors explained the associations. The cumulative incidence of convictions of theft (primarily petty theft) and other crimes was higher in exposed females (AN: 11.60% theft, 7.39% other convictions; BN: 17.97% theft, 13.17% other convictions) than in unexposed females (∼5% theft, ∼6% other convictions). The significantly increased risk...

The Journal of adolescent health : official publication of the Society for Adolescent Medicine, 2017

Disordered eating is more prevalent among adolescents with attention deficit/hyperactivity disord... more Disordered eating is more prevalent among adolescents with attention deficit/hyperactivity disorder. Both inattention and hyperactivity/impulsivity symptoms show strong associations with disordered eating, but few investigations of these associations have been longitudinal. Thus, we examined the effect of childhood to adolescent inattention and hyperactivity/impulsivity symptom trajectories on late adolescent disordered eating. We used growth mixture modeling to identify distinct inattention and hyperactivity/impulsivity symptom trajectories (called "classes") across three time points (ages 8-9, 13-14, and 16-17 years) in the Swedish Twin study of CHild and Adolescent Development. The resulting classes were used to predict Eating Disorder Inventory-2 Bulimia, Drive for Thinness, and Body Dissatisfaction subscales at age 16-17 years, with adjustment for sex and body mass index at age 16-17 years. The combined inattention and hyperactivity/impulsivity symptom trajectory clas...

Twin research and human genetics : the official journal of the International Society for Twin Studies, Jan 24, 2017

Genetic and environmental factors contribute to the etiology of anorexia nervosa (AN). The co-twi... more Genetic and environmental factors contribute to the etiology of anorexia nervosa (AN). The co-twin control design is one of the most powerful methods available to evaluate environmental factors that could contribute to differences between monozygotic (MZ) twins who are discordant for AN. Using available data from a unique and rare sample of 22 Swedish female MZ pairs discordant for AN, we compared personality, life events, comorbidity, and health factors. Twins with AN had significantly higher perfectionism scores than unaffected co-twins and reported younger ages at first diet than unaffected co-twins who had dieted. Consistent with previous literature, more twins with AN reported gastrointestinal problems than unaffected co-twins. Although not significant due to low statistical power, more unaffected co-twins reported experiencing emotional neglect than twins with AN. Early dieting may be a harbinger of the development of AN or an early symptom. Higher perfectionism may represent ...

The American journal of psychiatry, Sep 12, 2017

The authors conducted a genome-wide association study of anorexia nervosa and calculated genetic ... more The authors conducted a genome-wide association study of anorexia nervosa and calculated genetic correlations with a series of psychiatric, educational, and metabolic phenotypes. Following uniform quality control and imputation procedures using the 1000 Genomes Project (phase 3) in 12 case-control cohorts comprising 3,495 anorexia nervosa cases and 10,982 controls, the authors performed standard association analysis followed by a meta-analysis across cohorts. Linkage disequilibrium score regression was used to calculate genome-wide common variant heritability (single-nucleotide polymorphism [SNP]-based heritability [h(2)SNP]), partitioned heritability, and genetic correlations (rg) between anorexia nervosa and 159 other phenotypes. Results were obtained for 10,641,224 SNPs and insertion-deletion variants with minor allele frequencies >1% and imputation quality scores >0.6. The h(2)SNP of anorexia nervosa was 0.20 (SE=0.02), suggesting that a substantial fraction of the twin-ba...

The Australian and New Zealand journal of psychiatry, 2017

Anorexia nervosa is a severe psychiatric disorder with high mortality rates. While its aetiology ... more Anorexia nervosa is a severe psychiatric disorder with high mortality rates. While its aetiology is poorly understood, there is evidence of a significant genetic component. The Anorexia Nervosa Genetics Initiative is an international collaboration which aims to understand the genetic basis of the disorder. This paper describes the recruitment and characteristics of the Australasian Anorexia Nervosa Genetics Initiative sample, the largest sample of individuals with anorexia nervosa ever assembled across Australia and New Zealand. Participants completed an online questionnaire based on the Structured Clinical Interview Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) eating disorders section. Participants who met specified case criteria for lifetime anorexia nervosa were requested to provide a DNA sample for genetic analysis. Overall, the study recruited 3414 Australians and 543 New Zealanders meeting the lifetime anorexia nervosa case criteria by using a variet...

European eating disorders review : the journal of the Eating Disorders Association, May 9, 2017

Eating disorders and related symptoms occur during midlife; however, little is known about their ... more Eating disorders and related symptoms occur during midlife; however, little is known about their aetiology. It has been hypothesised that perimenopause represents a window of vulnerability for the development or exacerbation of eating disorder symptomatology because, like puberty, perimenopause is a period of reproductive hormone change. We compared symptoms of bulimia nervosa (bulimic symptomatology) assessed via mean scores on a self-report questionnaire in premenopausal and perimenopausal women. We also examined the association between hormone concentrations (reproductive/appetite) and bulimic symptomatology. No mean differences in bulimic symptomatology were observed between premenopause and perimenopause. However, there was a significant positive association between leptin and binge eating. Although no significant associations between reproductive hormones and bulimic symptomatology were observed, additional research is needed to provide definitive information. It is essential ...

The Primary Care Companion For CNS Disorders, 2016

Individuals with binge-eating disorder (BED) experience psychiatric and somatic comorbidities and... more Individuals with binge-eating disorder (BED) experience psychiatric and somatic comorbidities and obesity, but the nature and magnitude of prescription medication utilization is unclear. We investigated utilization using Swedish registry data and a case-control design. Cases were identified from Riksät and Stepwise longitudinal registers and were individuals diagnosed with BED per DSM-IV-TR criteria between July 1, 2006, and December 31, 2009, at eating disorder clinics (n = 238, 96% female, mean age = 22.8 years). For each case, 10 controls were matched on sex and year, month, and county of birth (n = 2,380). An index date was derived for each control, which was the date of diagnosis of BED in the corresponding case. The association between BED and prescription medication utilization was investigated before and within 12 months after diagnosis. Before diagnosis, cases were significantly more likely than matched controls to have been prescribed nervous system (odds ratio = 6.4; 95% confidence limit = 4.7, 8.6), tumors and immune disorders (3.5; 1.3, 9.3), cardiovascular (2.2; 1.4, 3.5), digestion and metabolism (2.1; 1.5, 2.9), infectious diseases (1.9; 1.4, 2.6), skin (1.8; 1.3, 2.5), and respiratory system (1.3; 1.0, 1.8) medications. Cases also had higher odds of prescription use than controls across most categories within 12 months after diagnosis. Several associations were significant after accounting for lifetime psychiatric comorbidity and obesity. Individuals with BED had increased utilization of psychiatric and nonpsychiatric medications compared with matched controls. Findings confirm that the illness burden of BED extends to high medication utilization and underscore the importance of thorough medication reviews when treating individuals with BED.

The Faseb Journal, Apr 1, 2010

Eating Behaviors, 2016

Binge and loss of control (LOC) eating are significant concerns among many adolescents and are as... more Binge and loss of control (LOC) eating are significant concerns among many adolescents and are associated with poor physical, social, and psychological functioning. Black girls appear to be particularly vulnerable to binge and LOC eating. Yet, empirically validated, culturally sensitive treatments for these disordered eating behaviors are not well established. This investigation examined satisfaction, feasibility, and preliminary outcomes of a binge eating intervention for ethnically diverse adolescent girls. Participants were 45 girls (age 13-17years; 44.4% white, 42.2% black) randomized into a dialectical behavior therapy (DBT)-based intervention (Linking Individuals Being Emotionally Real, LIBER8) or a weight management group (2BFit). Following each meeting, participants completed satisfaction measures, and therapists assessed intervention feasibility. Participants also completed assessments of eating behavior and related psychological constructs at baseline, immediately following the intervention, and at 3-month follow-up. Descriptive statistics indicated that LIBER8 was feasible, and participants were highly satisfied with this intervention. Significant reductions in eating disorder cognitions, dietary restraint, and eating in response to negative affect were observed for participants in both groups, with no differences between LIBER8 and 2BFit. The acceptability and feasibility of LIBER8 and associated reductions in emotional eating show promise in ameliorating binge eating and provide insight into multiple options for treating this challenging eating concern.

Disorders of the brain exhibit considerable epidemiological comorbidity and frequently share symp... more Disorders of the brain exhibit considerable epidemiological comorbidity and frequently share symptoms, provoking debate about the extent of their etiologic overlap. We quantified the genetic sharing of 25 brain disorders based on summary statistics from genome-wide association studies of 215,683 patients and 657,164 controls, and their relationship to 17 phenotypes from 1,191,588 individuals. Psychiatric disorders show substantial sharing of common variant risk, while neurological disorders appear more distinct from one another. We observe limited evidence of sharing between neurological and psychiatric disorders, but do identify robust sharing between disorders and several cognitive measures, as well as disorders and personality types. We also performed extensive simulations to explore how power, diagnostic misclassification and phenotypic heterogeneity affect genetic correlations. These results highlight the importance of common genetic variation as a source of risk for brain diso...

American Journal of Psychiatry, Nov 9, 2014

Although previous evidence has suggested that the etiologic role of stressful life events in majo... more Although previous evidence has suggested that the etiologic role of stressful life events in major depression is reduced in recurrent versus first-onset cases, this question deserves reexamination because of potential methodological limitations of the previous studies. Members of female-female twin pairs from a population-based registry (N=2,395), who were interviewed four times over a period of 9 years, formed a study group that contained 97,515 person-months and 1,380 onsets of major depression. Discrete-time survival, proportional hazards model, and piece-wise regression analyses were used to examine the interaction between life event exposure and number of previous depressive episodes in the prediction of episodes of major depression. For those with zero to nine previous depressive episodes, the depressogenic effect of stressful life events declined substantially with increasing episode number. However, the association between stressful life events and major depression was not substantially influenced by additional episodes. This pattern of results was robust to the addition of indices of event severity, measures of genetic risk, and restriction to independent stressful life events. The same pattern was also seen upon examining within-person changes in number of episodes. The association between previous number of depressive episodes and the pathogenic impact of stressful life events on major depression is likely causal and biphasic. Through approximately nine episodes, the association between stressful life event exposure and risk of major depression progressively declines but is largely unchanged with further episodes. These results are consistent with the kindling hypothesis but suggest a threshold at which the mind/brain is no longer additionally sensitized to the depressive state.

Suicide and Life-Threatening Behavior, 2016

The extent to which genetic and environmental factors influenced anorexia nervosa (AN), major dep... more The extent to which genetic and environmental factors influenced anorexia nervosa (AN), major depressive disorder (MDD), and suicide attempts (SA) were evaluated. Participants were 6,899 women from the Swedish Twin Study of Adults: Genes and Environment. A Cholesky decomposition assessed independent and overlapping genetic and environmental contributions to AN, MDD, and SA. Genetic factors accounted for a substantial amount of liability to all three traits; unique environmental factors accounted for most of the remaining liability. Shared genetic factors may underlie the coexpression of these traits. Results underscore the importance of assessing for signs of suicide among individuals with AN.

The International journal of eating disorders, Jan 29, 2015

We examined the association between the genetic and environmental factors contributing to the lia... more We examined the association between the genetic and environmental factors contributing to the liability to having ever engaged in self-induced vomiting (SIV initiation) and the genetic and environmental factors contributing to regular SIV behaviors (weekly or daily) for weight control. SIV was assessed in 3,942 women from monozygotic twin pairs and 2,790 women from same-sex dizygotic twin pairs, aged 20-47, from the Swedish Twin study of Adults: Genes and Environment. A causal-contingent-common pathway model assessed the extent to which genetic and environmental factors that influence initiation of SIV also influence regular SIV behaviors. In the best-fit model, genetic and individual-specific environmental factors influenced liability to SIV initiation. The genetic factors influencing regular SIV behaviors were the same as the genetic factors influencing SIV initiation. Additional individual-specific environmental factors that were unrelated to SIV initiation influenced regular SIV...

Contemporary Clinical Trials Communications

Contemporary clinical trials, 2018

Genetic factors contribute to anorexia nervosa (AN); and the first genome-wide significant locus ... more Genetic factors contribute to anorexia nervosa (AN); and the first genome-wide significant locus has been identified. We describe methods and procedures for the Anorexia Nervosa Genetics Initiative (ANGI), an international collaboration designed to rapidly recruit 13,000 individuals with AN and ancestrally matched controls. We present sample characteristics and the utility of an online eating disorder diagnostic questionnaire suitable for large-scale genetic and population research. ANGI recruited from the United States (US), Australia/New Zealand (ANZ), Sweden (SE), and Denmark (DK). Recruitment was via national registers (SE, DK); treatment centers (US, ANZ, SE, DK); and social and traditional media (US, ANZ, SE). All cases had a lifetime AN diagnosis based on DSM-IV or ICD-10 criteria (excluding amenorrhea). Recruited controls had no lifetime history of disordered eating behaviors. To assess the positive and negative predictive validity of the online eating disorder questionnaire...

European eating disorders review : the journal of the Eating Disorders Association, Jan 22, 2018

Anorexia nervosa (AN) and obsessive-compulsive disorder (OCD) are highly comorbid. However, the f... more Anorexia nervosa (AN) and obsessive-compulsive disorder (OCD) are highly comorbid. However, the factors that account for this comorbidity are poorly understood. We examined the core dimensions of AN and OCD and psychological and personality factors shared by both disorders. In path analyses (N = 732 women with either current AN or recovered from AN), we examined which factors were uniquely and independently associated with the core dimensions of AN and OCD. We also examined recovery from AN as a moderator. When individuals with AN reported greater concern over mistakes, they endorsed more severity in both AN and OCD core dimensions. These unique associations existed above and beyond all other transdiagnostic personality and psychological factors and regardless of AN recovery status. Concern over mistakes partially accounts for severity in the core dimensions of both AN and OCD. Concern over mistakes may represent an important target in the aetiology of AN and OCD.

Molecular psychiatry, Jan 7, 2018

Anorexia nervosa (AN) and obsessive-compulsive disorder (OCD) are often comorbid and likely to sh... more Anorexia nervosa (AN) and obsessive-compulsive disorder (OCD) are often comorbid and likely to share genetic risk factors. Hence, we examine their shared genetic background using a cross-disorder GWAS meta-analysis of 3495 AN cases, 2688 OCD cases, and 18,013 controls. We confirmed a high genetic correlation between AN and OCD (r = 0.49 ± 0.13, p = 9.07 × 10) and a sizable SNP heritability (SNP h = 0.21 ± 0.02) for the cross-disorder phenotype. Although no individual loci reached genome-wide significance, the cross-disorder phenotype showed strong positive genetic correlations with other psychiatric phenotypes (e.g., r = 0.36 with bipolar disorder and 0.34 with neuroticism) and negative genetic correlations with metabolic phenotypes (e.g., r = -0.25 with body mass index and -0.20 with triglycerides). Follow-up analyses revealed that although AN and OCD overlap heavily in their shared risk with other psychiatric phenotypes, the relationship with metabolic and anthropometric traits is...

The International journal of eating disorders, 2017

Previous studies evaluating the association between early childhood adversities and eating disord... more Previous studies evaluating the association between early childhood adversities and eating disorders have yielded conflicting results. The aim of this study is to examine the association between a range of adversities and risk of anorexia nervosa (AN), bulimia nervosa (BN), and eating disorder not otherwise specified (EDNOS) in 495,244 women. In this nationwide, register-based cohort study, nine types of early childhood adversity (family disruption, residential instability, placement in out-of-home care, familial death, parental somatic illness, parental psychiatric illness, parental disability, severe parental criminality, and parental substance use disorder) were defined and exposure during the first 6 years of life was determined. Hazard ratios for eating disorders were calculated using Cox regression. Few adversities were significantly associated with AN, and for each, the presence of the adversity was associated with lower risk for AN. BN, and EDNOS were positively associated w...

Pediatrics, 2017

Identifying factors associated with risk for eating disorders is important for clarifying etiolog... more Identifying factors associated with risk for eating disorders is important for clarifying etiology and for enhancing early detection of eating disorders in primary care. We hypothesized that autoimmune and autoinflammatory diseases would be associated with eating disorders in children and adolescents and that family history of these illnesses would be associated with eating disorders in probands. In this large, nationwide, population-based cohort study of all children and adolescents born in Denmark between 1989 and 2006 and managed until 2012, Danish medical registers captured all inpatient and outpatient diagnoses of eating disorders and autoimmune and autoinflammatory diseases. The study population included 930 977 individuals (48.7% girls). Cox proportional hazards regression models and logistic regression were applied to evaluate associations. We found significantly higher hazards of eating disorders for children and adolescents with autoimmune or autoinflammatory diseases: 36%...

The International journal of eating disorders, 2017

We examined epidemiological associations between anorexia nervosa (AN) and bulimia nervosa (BN) a... more We examined epidemiological associations between anorexia nervosa (AN) and bulimia nervosa (BN) and risks of committing theft and other crimes in a nationwide female population. Females born in Sweden during 1979-1998 (N = 957,106) were followed from age 15 for up to 20 years using information on clinically diagnosed AN and BN (exposures), convictions of theft and other crimes (outcomes), psychiatric comorbidities, and familial relatedness from Swedish national registers. We estimated hazard ratios (HRs) of criminality in exposed versus unexposed females using Cox proportional hazards regressions and explored how comorbidities and unmeasured familial factors explained the associations. The cumulative incidence of convictions of theft (primarily petty theft) and other crimes was higher in exposed females (AN: 11.60% theft, 7.39% other convictions; BN: 17.97% theft, 13.17% other convictions) than in unexposed females (∼5% theft, ∼6% other convictions). The significantly increased risk...

The Journal of adolescent health : official publication of the Society for Adolescent Medicine, 2017

Disordered eating is more prevalent among adolescents with attention deficit/hyperactivity disord... more Disordered eating is more prevalent among adolescents with attention deficit/hyperactivity disorder. Both inattention and hyperactivity/impulsivity symptoms show strong associations with disordered eating, but few investigations of these associations have been longitudinal. Thus, we examined the effect of childhood to adolescent inattention and hyperactivity/impulsivity symptom trajectories on late adolescent disordered eating. We used growth mixture modeling to identify distinct inattention and hyperactivity/impulsivity symptom trajectories (called "classes") across three time points (ages 8-9, 13-14, and 16-17 years) in the Swedish Twin study of CHild and Adolescent Development. The resulting classes were used to predict Eating Disorder Inventory-2 Bulimia, Drive for Thinness, and Body Dissatisfaction subscales at age 16-17 years, with adjustment for sex and body mass index at age 16-17 years. The combined inattention and hyperactivity/impulsivity symptom trajectory clas...

Twin research and human genetics : the official journal of the International Society for Twin Studies, Jan 24, 2017

Genetic and environmental factors contribute to the etiology of anorexia nervosa (AN). The co-twi... more Genetic and environmental factors contribute to the etiology of anorexia nervosa (AN). The co-twin control design is one of the most powerful methods available to evaluate environmental factors that could contribute to differences between monozygotic (MZ) twins who are discordant for AN. Using available data from a unique and rare sample of 22 Swedish female MZ pairs discordant for AN, we compared personality, life events, comorbidity, and health factors. Twins with AN had significantly higher perfectionism scores than unaffected co-twins and reported younger ages at first diet than unaffected co-twins who had dieted. Consistent with previous literature, more twins with AN reported gastrointestinal problems than unaffected co-twins. Although not significant due to low statistical power, more unaffected co-twins reported experiencing emotional neglect than twins with AN. Early dieting may be a harbinger of the development of AN or an early symptom. Higher perfectionism may represent ...

The American journal of psychiatry, Sep 12, 2017

The authors conducted a genome-wide association study of anorexia nervosa and calculated genetic ... more The authors conducted a genome-wide association study of anorexia nervosa and calculated genetic correlations with a series of psychiatric, educational, and metabolic phenotypes. Following uniform quality control and imputation procedures using the 1000 Genomes Project (phase 3) in 12 case-control cohorts comprising 3,495 anorexia nervosa cases and 10,982 controls, the authors performed standard association analysis followed by a meta-analysis across cohorts. Linkage disequilibrium score regression was used to calculate genome-wide common variant heritability (single-nucleotide polymorphism [SNP]-based heritability [h(2)SNP]), partitioned heritability, and genetic correlations (rg) between anorexia nervosa and 159 other phenotypes. Results were obtained for 10,641,224 SNPs and insertion-deletion variants with minor allele frequencies >1% and imputation quality scores >0.6. The h(2)SNP of anorexia nervosa was 0.20 (SE=0.02), suggesting that a substantial fraction of the twin-ba...

The Australian and New Zealand journal of psychiatry, 2017

Anorexia nervosa is a severe psychiatric disorder with high mortality rates. While its aetiology ... more Anorexia nervosa is a severe psychiatric disorder with high mortality rates. While its aetiology is poorly understood, there is evidence of a significant genetic component. The Anorexia Nervosa Genetics Initiative is an international collaboration which aims to understand the genetic basis of the disorder. This paper describes the recruitment and characteristics of the Australasian Anorexia Nervosa Genetics Initiative sample, the largest sample of individuals with anorexia nervosa ever assembled across Australia and New Zealand. Participants completed an online questionnaire based on the Structured Clinical Interview Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) eating disorders section. Participants who met specified case criteria for lifetime anorexia nervosa were requested to provide a DNA sample for genetic analysis. Overall, the study recruited 3414 Australians and 543 New Zealanders meeting the lifetime anorexia nervosa case criteria by using a variet...

European eating disorders review : the journal of the Eating Disorders Association, May 9, 2017

Eating disorders and related symptoms occur during midlife; however, little is known about their ... more Eating disorders and related symptoms occur during midlife; however, little is known about their aetiology. It has been hypothesised that perimenopause represents a window of vulnerability for the development or exacerbation of eating disorder symptomatology because, like puberty, perimenopause is a period of reproductive hormone change. We compared symptoms of bulimia nervosa (bulimic symptomatology) assessed via mean scores on a self-report questionnaire in premenopausal and perimenopausal women. We also examined the association between hormone concentrations (reproductive/appetite) and bulimic symptomatology. No mean differences in bulimic symptomatology were observed between premenopause and perimenopause. However, there was a significant positive association between leptin and binge eating. Although no significant associations between reproductive hormones and bulimic symptomatology were observed, additional research is needed to provide definitive information. It is essential ...

The Primary Care Companion For CNS Disorders, 2016

Individuals with binge-eating disorder (BED) experience psychiatric and somatic comorbidities and... more Individuals with binge-eating disorder (BED) experience psychiatric and somatic comorbidities and obesity, but the nature and magnitude of prescription medication utilization is unclear. We investigated utilization using Swedish registry data and a case-control design. Cases were identified from Riksät and Stepwise longitudinal registers and were individuals diagnosed with BED per DSM-IV-TR criteria between July 1, 2006, and December 31, 2009, at eating disorder clinics (n = 238, 96% female, mean age = 22.8 years). For each case, 10 controls were matched on sex and year, month, and county of birth (n = 2,380). An index date was derived for each control, which was the date of diagnosis of BED in the corresponding case. The association between BED and prescription medication utilization was investigated before and within 12 months after diagnosis. Before diagnosis, cases were significantly more likely than matched controls to have been prescribed nervous system (odds ratio = 6.4; 95% confidence limit = 4.7, 8.6), tumors and immune disorders (3.5; 1.3, 9.3), cardiovascular (2.2; 1.4, 3.5), digestion and metabolism (2.1; 1.5, 2.9), infectious diseases (1.9; 1.4, 2.6), skin (1.8; 1.3, 2.5), and respiratory system (1.3; 1.0, 1.8) medications. Cases also had higher odds of prescription use than controls across most categories within 12 months after diagnosis. Several associations were significant after accounting for lifetime psychiatric comorbidity and obesity. Individuals with BED had increased utilization of psychiatric and nonpsychiatric medications compared with matched controls. Findings confirm that the illness burden of BED extends to high medication utilization and underscore the importance of thorough medication reviews when treating individuals with BED.

The Faseb Journal, Apr 1, 2010

Eating Behaviors, 2016

Binge and loss of control (LOC) eating are significant concerns among many adolescents and are as... more Binge and loss of control (LOC) eating are significant concerns among many adolescents and are associated with poor physical, social, and psychological functioning. Black girls appear to be particularly vulnerable to binge and LOC eating. Yet, empirically validated, culturally sensitive treatments for these disordered eating behaviors are not well established. This investigation examined satisfaction, feasibility, and preliminary outcomes of a binge eating intervention for ethnically diverse adolescent girls. Participants were 45 girls (age 13-17years; 44.4% white, 42.2% black) randomized into a dialectical behavior therapy (DBT)-based intervention (Linking Individuals Being Emotionally Real, LIBER8) or a weight management group (2BFit). Following each meeting, participants completed satisfaction measures, and therapists assessed intervention feasibility. Participants also completed assessments of eating behavior and related psychological constructs at baseline, immediately following the intervention, and at 3-month follow-up. Descriptive statistics indicated that LIBER8 was feasible, and participants were highly satisfied with this intervention. Significant reductions in eating disorder cognitions, dietary restraint, and eating in response to negative affect were observed for participants in both groups, with no differences between LIBER8 and 2BFit. The acceptability and feasibility of LIBER8 and associated reductions in emotional eating show promise in ameliorating binge eating and provide insight into multiple options for treating this challenging eating concern.

Disorders of the brain exhibit considerable epidemiological comorbidity and frequently share symp... more Disorders of the brain exhibit considerable epidemiological comorbidity and frequently share symptoms, provoking debate about the extent of their etiologic overlap. We quantified the genetic sharing of 25 brain disorders based on summary statistics from genome-wide association studies of 215,683 patients and 657,164 controls, and their relationship to 17 phenotypes from 1,191,588 individuals. Psychiatric disorders show substantial sharing of common variant risk, while neurological disorders appear more distinct from one another. We observe limited evidence of sharing between neurological and psychiatric disorders, but do identify robust sharing between disorders and several cognitive measures, as well as disorders and personality types. We also performed extensive simulations to explore how power, diagnostic misclassification and phenotypic heterogeneity affect genetic correlations. These results highlight the importance of common genetic variation as a source of risk for brain diso...

American Journal of Psychiatry, Nov 9, 2014

Although previous evidence has suggested that the etiologic role of stressful life events in majo... more Although previous evidence has suggested that the etiologic role of stressful life events in major depression is reduced in recurrent versus first-onset cases, this question deserves reexamination because of potential methodological limitations of the previous studies. Members of female-female twin pairs from a population-based registry (N=2,395), who were interviewed four times over a period of 9 years, formed a study group that contained 97,515 person-months and 1,380 onsets of major depression. Discrete-time survival, proportional hazards model, and piece-wise regression analyses were used to examine the interaction between life event exposure and number of previous depressive episodes in the prediction of episodes of major depression. For those with zero to nine previous depressive episodes, the depressogenic effect of stressful life events declined substantially with increasing episode number. However, the association between stressful life events and major depression was not substantially influenced by additional episodes. This pattern of results was robust to the addition of indices of event severity, measures of genetic risk, and restriction to independent stressful life events. The same pattern was also seen upon examining within-person changes in number of episodes. The association between previous number of depressive episodes and the pathogenic impact of stressful life events on major depression is likely causal and biphasic. Through approximately nine episodes, the association between stressful life event exposure and risk of major depression progressively declines but is largely unchanged with further episodes. These results are consistent with the kindling hypothesis but suggest a threshold at which the mind/brain is no longer additionally sensitized to the depressive state.

Suicide and Life-Threatening Behavior, 2016

The extent to which genetic and environmental factors influenced anorexia nervosa (AN), major dep... more The extent to which genetic and environmental factors influenced anorexia nervosa (AN), major depressive disorder (MDD), and suicide attempts (SA) were evaluated. Participants were 6,899 women from the Swedish Twin Study of Adults: Genes and Environment. A Cholesky decomposition assessed independent and overlapping genetic and environmental contributions to AN, MDD, and SA. Genetic factors accounted for a substantial amount of liability to all three traits; unique environmental factors accounted for most of the remaining liability. Shared genetic factors may underlie the coexpression of these traits. Results underscore the importance of assessing for signs of suicide among individuals with AN.

The International journal of eating disorders, Jan 29, 2015

We examined the association between the genetic and environmental factors contributing to the lia... more We examined the association between the genetic and environmental factors contributing to the liability to having ever engaged in self-induced vomiting (SIV initiation) and the genetic and environmental factors contributing to regular SIV behaviors (weekly or daily) for weight control. SIV was assessed in 3,942 women from monozygotic twin pairs and 2,790 women from same-sex dizygotic twin pairs, aged 20-47, from the Swedish Twin study of Adults: Genes and Environment. A causal-contingent-common pathway model assessed the extent to which genetic and environmental factors that influence initiation of SIV also influence regular SIV behaviors. In the best-fit model, genetic and individual-specific environmental factors influenced liability to SIV initiation. The genetic factors influencing regular SIV behaviors were the same as the genetic factors influencing SIV initiation. Additional individual-specific environmental factors that were unrelated to SIV initiation influenced regular SIV...