Laura Thornton
University of North Carolina at Chapel Hill, Psychiatry, Faculty Member
Research Interests:
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... 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...
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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... 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.
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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... 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...
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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... 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...
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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... 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%...
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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... 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...
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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... 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...
Research Interests: Education, Adolescent Development, Adolescent Health, Adolescent, Sweden, and 12 moreHumans, Child, Female, Male, Risk factors, Disease Progression, Risk Factors, Psychiatric Status Rating Scales, Attention deficit disorder with hyperactivity, Feeding and Eating Disorders, Psychology and Cognitive Sciences, and Medical and Health Sciences
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... 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 ...
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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... 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...
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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... 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...
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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... 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 ...
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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... 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.
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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.... 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.
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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... 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...
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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... 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.
Research Interests: Genetics, Depression, Comparative Study, Humans, Coping, and 15 moreFemale, American, Depressive Disorder, Etiology, Major Depression, Longitudinal Studies, Adult, Odds ratio, Psychological Models, Discrete Time Systems, Proportional Hazards Models, Life Change Events, LIFE EVENT, Discrete time, and Medical and Health Sciences
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... 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.
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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... 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...
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China is undergoing dramatic Westernization, hence may be able to provide unique insights into the role of sociocultural factors in disease. The purpose of this exploratory study was two-fold: to describe the prevalence of... more
China is undergoing dramatic Westernization, hence may be able to provide unique insights into the role of sociocultural factors in disease. The purpose of this exploratory study was two-fold: to describe the prevalence of screening-detected eating disorders and disordered eating in China at the first occasion of assessment in the large-scale China Health and Nutrition Survey (CHNS) and to explore the associations between dietary practices and disordered eating. Regarding the first objective, participants are provincially representative and in subsequent waves will be followed longitudinally. CHNS participants were recruited using multistage, cluster random sampling, beginning in 1989. In this study, participants comprised 259 female adolescents (12-17 years) and 979 women (18-35 years) who participated in the CHNS 2009 survey, which is the first CHNS survey to assess disordered eating. Dietary practice-disordered eating associations were investigated with logistic regression adjusting for age, body mass index, and urbanization. Of the participants, 6.3% (95% CI: 4.8, 8.2) of adults and 7.8% (95% CI: 5.0, 12.0) of adolescents had a screening-detected eating disorder. Dietary practices had non-significant associations with disordered eating at the general population level, except for protein consumption among women. There was evidence that skipping meals and a high-fat diet may confer risk. Screening-detected eating disorders in China are lower in prevalence than in developed countries. Dietary practices had fairly limited associations with disordered eating at the general population level; protein consumption, skipping meals, and a high-fat diet are candidate dietary practice exposures for disordered eating. Copyright © 2014 John Wiley & Sons, Ltd and Eating Disorders Association.
Research Interests: Eating Disorders, Diet, China, Adolescent, Humans, and 15 moreChild, Female, Body Composition, Nutritional Status, Body Mass Index, Feeding Behavior, Clinical Sciences, Prevalence, Longitudinal Studies, Adult, Health surveys, Asian Continental Ancestry Group, Logistic Models, cultural characteristics, and mass Screening
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This study compares personality variables of men with eating disorders to women with eating disorders. Data were obtained from an international study of the genetics of eating disorders. Forty-two male participants were age-band matched... more
This study compares personality variables of men with eating disorders to women with eating disorders. Data were obtained from an international study of the genetics of eating disorders. Forty-two male participants were age-band matched at 1:2 ratio to females from the same study. Personality features were compared between males and females controlling for diagnostic subgroup. Males with eating disorders appear to be slightly less at risk for perfectionism, harm avoidance, reward dependence, and cooperativeness than females. Few differences were found when diagnostic subgroup was considered. Observed differences in personality variables may help explain the difference in incidence and prevalence of eating disorders in men and women.
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Eating disorders and alcohol use disorders (AUDs) commonly co-occur, although the patterns of comorbidity differ by eating disorder subtype. Our aim was to explore the nature of the co-morbid relation between AUDs and eating disorders in... more
Eating disorders and alcohol use disorders (AUDs) commonly co-occur, although the patterns of comorbidity differ by eating disorder subtype. Our aim was to explore the nature of the co-morbid relation between AUDs and eating disorders in a large and phenotypically well-characterized group of individuals. We compared diagnostic and personality profiles of 97 women with lifetime anorexia nervosa only, 282 women with lifetime bulimia nervosa only, and 293 women with a lifetime history of both anorexia nervosa and bulimia nervosa or anorexia nervosa with binge eating (ANBN) (DSM-IV criteria). All individuals were participants in a multicenter study of the genetics of anorexia nervosa and bulimia nervosa. We explored pattern of onset, Axis I and II comorbidity, and personality characteristics of individuals with and without AUDs by eating disorder subtype. Personality characteristics were assessed with the Multidimensional Perfectionism Scale, the Temperament and Character Inventory, and the Barratt Impulsivity Scale. Alcohol use disorders were significantly more prevalent in women with ANBN and bulimia nervosa than in women with anorexia nervosa (p =.0001). The majority of individuals reported primary onset of the eating disorder, with only one third reporting the onset of the AUD first. After eating disorder subtype was controlled for, AUDs were associated with the presence of major depressive disorder, a range of anxiety disorders, and cluster B personality disorder symptoms. In addition, individuals with AUDs presented with personality profiles marked by impulsivity and perfectionism. Individuals with eating disorders and AUDs exhibit phenotypic profiles characterized by both anxious, perfectionistic traits and impulsive, dramatic dispositions. These traits mirror the pattern of control and dyscontrol seen in individuals with this comorbid profile and suggest that anxiety modulation may be related to alcohol use in this group.
Research Interests: Eating Disorders, Personality Assessment, Comorbidity, Anorexia Nervosa, Humans, and 15 morePersonality Assessment Inventory, North Carolina, Female, Clinical, Mental Disorders, Phenotype, Prevalence, Eating Disorder, Bulimia, Logistic Models, Age of Onset, Psychiatric Status Rating Scales, Personality Inventory, Alcohol use disorder, and Medical and Health Sciences
To further refine our understanding of impulsivity, obsessions, and compulsions in anorexia nervosa (AN) by isolating which behaviours--binge eating, purging, or both--are associated with these features. We conducted regression analyses... more
To further refine our understanding of impulsivity, obsessions, and compulsions in anorexia nervosa (AN) by isolating which behaviours--binge eating, purging, or both--are associated with these features. We conducted regression analyses with binge eating, purging, and the interaction of binge eating with purging as individual predictors of scores for impulsivity, obsessions, and compulsions in two samples of women with AN (n = 1373). Purging, but not binge eating, was associated with higher scores on impulsivity, obsessions, and compulsions. Purging was also associated with worst eating rituals and with worst eating preoccupations. Our results suggest that purging, compared with binge eating, may be a stronger correlate of impulsivity, obsessions, and compulsions in AN.
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Objective: While family and twin studies suggest that retrospectively reported premenstrual symptoms are heritable, these studies have not accounted for the unreliability of such measures. In addition, we know little about the... more
Objective: While family and twin studies suggest that retrospectively reported premenstrual symptoms are heritable, these studies have not accounted for the unreliability of such measures. In addition, we know little about the relationship of the familial risk factors for premenstrual symptoms and major depression. Method: Lifetime major depression and premenstrual-related tiredness, sadness, and irritability were assessed twice over 6 years in 1,312 menstruating female twins ascertained from a population-based twin register. A twin ...
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Research Interests: Genetics, Psychology, Aging, Behavior Genetics, Mice, and 8 moreFemale, Animals, Male, Ultrasonics, Arousal, Genotype, Neurosciences, and Maternal Effect
Comorbidity among eating disorders, traumatic events, and posttraumatic stress disorder (PTSD) has been reported in several studies. The main objectives of this study were to describe the nature of traumatic events experienced and to... more
Comorbidity among eating disorders, traumatic events, and posttraumatic stress disorder (PTSD) has been reported in several studies. The main objectives of this study were to describe the nature of traumatic events experienced and to explore the relationship between PTSD and anorexia nervosa (AN) in a sample of women. Eight hundred twenty-four participants from the National Institutes of Health-funded Genetics of Anorexia Nervosa Collaborative Study were assessed for eating disorders, PTSD, and personality characteristics. From a final sample of 753 women with AN, 13.7% (n = 103) met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria for PTSD. The sample mean age was 29.5 (standard deviation = 11.1) years. In pairwise comparisons across AN subtypes, the odds of having a PTSD diagnosis were significantly lower in individuals with restricting AN than individuals with purging AN without binge eating (odds ratio = 0.49, 95% confidence interval = 0.30-0.80). Most participants with PTSD reported the first traumatic event before the onset of AN (64.1%, n = 66). The most common traumatic events reported by those with a PTSD diagnosis were sexually related traumas during childhood (40.8%) and during adulthood (35.0%). AN and PTSD do co-occur, and traumatic events tend to occur before the onset of AN. Clinically, these results underscore the importance of assessing trauma history and PTSD in individuals with AN and raise the question of whether specific modifications or augmentations to standard treatment for AN should be considered in a subgroup to address PTSD-related psychopathology.
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Suicide attempts are common in individuals with eating disorders. More precise understanding of the mechanisms underlying their concomitant occurrence is needed. To examine the association between eating disorders and suicide attempts and... more
Suicide attempts are common in individuals with eating disorders. More precise understanding of the mechanisms underlying their concomitant occurrence is needed. To examine the association between eating disorders and suicide attempts and whether familial risk factors contribute to the association. A Swedish birth cohort including individuals born in Sweden between January 1, 1979, and December 31, 2001, was followed up from age 6 years to December 31, 2009 (N = 2 268 786). Information was acquired from Swedish national registers. All individuals were linked to their biological full siblings, maternal half siblings, paternal half siblings, full cousins, and half cousins. Data analysis was conducted from October 5, 2014, to April 28, 2015. Eating disorders were captured by 3 variables (any eating disorder, anorexia nervosa, and bulimia nervosa) identified by any lifetime diagnoses recorded in the registers. Suicide attempts were defined as any suicide attempts, including death by sui...
To investigate the sex- and age-specific incidence of healthcare-register-recorded anorexia nervosa (AN) and other eating disorders (OED) in a complete birth cohort, and assess whether incidence varies by diagnostic period and (sub-)... more
To investigate the sex- and age-specific incidence of healthcare-register-recorded anorexia nervosa (AN) and other eating disorders (OED) in a complete birth cohort, and assess whether incidence varies by diagnostic period and (sub-) birth cohort. We used the actuarial method and Poisson models to examine the incidence of AN and OED from 1987 to 2009 (when individuals were 8-30 years old) for a cohort of 2.3 million individuals (48.7% female) born from 1979 to 2001 in Sweden, identified using Swedish registers. For both sexes, incidences of AN and OED increased considerably for diagnostic periods after 2000, but differed little by birth cohort. In 2009, AN incidence in the peak age category was 205.9 cases/100,000 persons (95% CI: 178.2, 233.5) for females (14-15 years), versus 12.8 cases/100,000 (95% CI: 5.6, 20.1) for males (12-13 years). OED incidence in the peak age category was 372.1 cases/100,000 (95% CI: 336.4, 407.9) for females (16-17 years), versus 22.2 cases/100,000 (95% CI: 13.3, 31.1) for males (14-15 years). Our finding of an increase in healthcare-register-recorded eating disorders for diagnostic periods after 2000 likely reflects improved detection and expanded register coverage in Sweden. The peak of eating disorder incidence in adolescence, which began unexpectedly early for AN in males, suggests the importance of vigilance for signs of AN in young boys and early primary prevention efforts. Waiting until later could miss critical windows for intervention that could prevent disorders from taking root. © 2015 Wiley Periodicals, Inc. (Int J Eat Disord 2015; 48:1070-1081).
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A large and well-characterized sample of individuals with anorexia nervosa and bulimia nervosa from the Price Foundation collaborative genetics study was used to determine the frequency of anxiety disorders and to understand how anxiety... more
A large and well-characterized sample of individuals with anorexia nervosa and bulimia nervosa from the Price Foundation collaborative genetics study was used to determine the frequency of anxiety disorders and to understand how anxiety disorders are related to state of eating disorder illness and age at onset. Ninety-seven individuals with anorexia nervosa, 282 with bulimia nervosa, and 293 with anorexia nervosa and bulimia were given the Structured Clinical Interview for DSM-IV Axis I Disorders and standardized measures of anxiety, perfectionism, and obsessionality. Their ratings on these measures were compared with those of a nonclinical group of women in the community. The rates of most anxiety disorders were similar in all three subtypes of eating disorders. About two-thirds of the individuals with eating disorders had one or more lifetime anxiety disorder; the most common were obsessive-compulsive disorder (OCD) (N=277 [41%]) and social phobia (N=134 [20%]). A majority of the participants reported the onset of OCD, social phobia, specific phobia, and generalized anxiety disorder in childhood, before they developed an eating disorder. People with a history of an eating disorder who were not currently ill and never had a lifetime anxiety disorder diagnosis still tended to be anxious, perfectionistic, and harm avoidant. The presence of either an anxiety disorder or an eating disorder tended to exacerbate these symptoms. The prevalence of anxiety disorders in general and OCD in particular was much higher in people with anorexia nervosa and bulimia nervosa than in a nonclinical group of women in the community. Anxiety disorders commonly had their onset in childhood before the onset of an eating disorder, supporting the possibility they are a vulnerability factor for developing anorexia nervosa or bulimia nervosa.
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Obsessive-compulsive disorder (OCD) often co-occurs with anorexia nervosa (AN), a comorbid profile that complicates the clinical management of both conditions. This population-based study aimed to examine patterns of comorbidity,... more
Obsessive-compulsive disorder (OCD) often co-occurs with anorexia nervosa (AN), a comorbid profile that complicates the clinical management of both conditions. This population-based study aimed to examine patterns of comorbidity, longitudinal risks, shared familial risks and shared genetic factors between OCD and AN at the population level. Participants were individuals with a diagnosis of OCD (N=19,814) or AN (N=8,462) in the Swedish National Patient Register between January 1992 and December 2009; their first-, second- and third-degree relatives; and population-matched (1:10 ratio) unaffected comparison individuals and their relatives. Female twins from the population-based Swedish Twin Register (N=8,550) were also included. Females with OCD had a 16-fold increased risk of having a comorbid diagnosis of AN, whereas males with OCD had a 37-fold increased risk. Longitudinal analyses showed that individuals first diagnosed with OCD had an increased risk for a later diagnosis of AN (r...
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CHAPTER FIVE Health, Well-Being, and Social Responsibility in the MIDUS Twin and Sibling Subsamples Ronald C. Kessler, Stephen E. Oilman, Laura M. Thornton, and Kenneth S. Kendler One of the special design features of MIDUS was the... more
CHAPTER FIVE Health, Well-Being, and Social Responsibility in the MIDUS Twin and Sibling Subsamples Ronald C. Kessler, Stephen E. Oilman, Laura M. Thornton, and Kenneth S. Kendler One of the special design features of MIDUS was the augmentation of the general ...
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Anxiety disorders and anorexia nervosa are frequently acknowledged to be highly comorbid conditions, but still, little is known about the clinical and aetiological cohesion of specific anxiety diagnoses and anorexia nervosa. Using the... more
Anxiety disorders and anorexia nervosa are frequently acknowledged to be highly comorbid conditions, but still, little is known about the clinical and aetiological cohesion of specific anxiety diagnoses and anorexia nervosa. Using the comprehensive Danish population registers, we aimed to determine the risk of anorexia nervosa in patients with register-detected severe anxiety disorders. We also explored whether parental psychopathology was associated with offspring's anorexia nervosa. Anxiety disorders increased the risk of subsequent anorexia nervosa, with the highest risk observed in obsessive-compulsive disorder. Especially, male anxiety patients were at an increased risk for anorexia nervosa. Furthermore, an increased risk was observed in offspring of fathers with panic disorder. A diagnosis of an anxiety disorder, specifically obsessive-compulsive disorder, constitutes a risk factor for subsequent diagnosis of anorexia nervosa. These observations support the notion that anxiety disorders and anorexia nervosa share etiological mechanisms and/or that anxiety represents one developmental pathway to anorexia nervosa. Copyright © 2015 John Wiley & Sons, Ltd and Eating Disorders Association.
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Family, twin, and adoption studies of anorexia nervosa (AN), bulimia nervosa (BN), binge-eating disorder (BED), and the proposed purging disorder presentation (PD) have consistently demonstrated that genetic factors contribute to the... more
Family, twin, and adoption studies of anorexia nervosa (AN), bulimia nervosa (BN), binge-eating disorder (BED), and the proposed purging disorder presentation (PD) have consistently demonstrated that genetic factors contribute to the variance in liability to eating disorders. In addition, endophenotypes and component phenotypes of eating disorders have been evaluated and provide further insight regarding genetic factors influencing eating disorders and eating disorder diagnostic criteria. Many of these phenotypes have demonstrated substantial heritability. This chapter reviews biometrical genetic methods and current findings from family and twin studies that investigate the role of genes and environment in the etiology of eating disorders. We review the methodology used to estimate heritability, the results of these studies, and discuss the implications of this research for the basic conceptualization of eating disorders and the future value of twin modeling in the molecular genetic...
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Alcoholism is clinically heterogeneous. We have attempted to identify and validate subtypes of broadly defined alcoholism. Latent class analysis (LCA) was applied to data on the number, age at onset and reasons for temperance board... more
Alcoholism is clinically heterogeneous. We have attempted to identify and validate subtypes of broadly defined alcoholism. Latent class analysis (LCA) was applied to data on the number, age at onset and reasons for temperance board registration (TBR) in all male-male twin pairs of known zygosity born in Sweden from 1902-1949. Of the five classes identified, two were relatively common: single-cause registrant-drunk (SCR-D); and early-onset multiple-cause registrant (EO-MCR). In contrast to the SCR-D class, the EO-MCR class was characterized by: (i) earlier age at first TBR; (ii) higher number of TBRs; (iii) TBRs for drunk driving and alcohol-related crimes; (iv) much higher risk for alcohol-related imprisonment and hospitalization; (v) higher levels of neuroticism and novelty-seeking; and (vi) much greater risk for TBR in co-twins. In twin pairs concordant for TBR, concordance for LCA-derived class assignment far exceeded chance expectation, more so in monozygotic than in dizygotic p...
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The authors sought to determine whether the clinical manifestations of schizophrenia and other psychotic disorders are correlated in affected sibling pairs. They examined, in 256 sibling pairs concordant for DSM-III-R schizophrenia and... more
The authors sought to determine whether the clinical manifestations of schizophrenia and other psychotic disorders are correlated in affected sibling pairs. They examined, in 256 sibling pairs concordant for DSM-III-R schizophrenia and 457 sibling pairs concordant for all nonaffective psychoses ascertained in the Irish Study of High-Density Schizophrenia Families, similarity for 1) symptoms, course, and outcome; 2) symptom factors; and 3) syndromes, defined by latent class analysis. Global course and outcome, as well as all major symptoms except hallucinations, were modestly but significantly correlated in sibling pairs concordant for schizophrenia. Three symptom factors-negative symptoms, positive symptoms, and affective symptoms-were all significantly correlated in concordant sib pairs. Latent class analysis suggested five schizophrenic syndromes. Class membership was significantly correlated in concordant sibling pairs. Similar results were found for sibling pairs concordant for ...
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We examined the association among current self-reported sleep problems, lifetime binge eating (BE), and current obesity in women from the Swedish Twin study of Adults: Genes and Environment. Logistic regression analyses were used to... more
We examined the association among current self-reported sleep problems, lifetime binge eating (BE), and current obesity in women from the Swedish Twin study of Adults: Genes and Environment. Logistic regression analyses were used to evaluate these associations in 3,790 women aged 20-47 years. BE was reported by 244 (6.4%) women and was positively associated with not getting enough sleep (p < .015), sleeping poorly (p < .001), problems falling asleep (p < .001), feeling sleepy during work or free time (p < .001), and disturbed sleep (p < .001). These same sleep variables, as well as napping and being a night person, were also significantly associated with obesity. The associations between BE and sleep remained after accounting for obesity. This investigation offers empirical support for an independent association between sleep problems and BE, which is likely due to complex psychological, biological, neuroendocrine, and metabolic factors.