A controlled family history study of bulimia

Rigor and reproducibility in genetic research on eating disorders

OBJECTIVE

We explored both within-method and between-method rigor and reproducibility in the field of eating disorders genetics.

METHOD

We present critical evaluation and commentary on component methods of genetic research (family studies, twin studies, molecular genetic studies) and discuss both successful and unsuccessful efforts in the field.

RESULTS

Eating disorders genetics has had a number of robust results that converge across component methodologies. Familial aggregation of eating disorders, twin-based heritability estimates of eating disorders, and genome-wide association studies (GWAS) all point toward a substantial role for genetics in eating disorders etiology and support the premise that genes do not act alone. Candidate gene and linkage studies have been less informative historically.

DISCUSSION

The eating disorders field has entered the GWAS era with studies of anorexia nervosa. Continued growth of sample sizes is essential for rigorous discovery of actionable variation. Molecular genetic studies of bulimia nervosa, binge-eating disorder, and other eating disorders are virtually nonexistent and lag seriously behind other major psychiatric disorders. Expanded efforts are necessary to reveal the fundamental biology of eating disorders, inform clinical practice, and deliver new therapeutic targets.

Predictors and long-term health outcomes of eating disorders

Anorexia and bulimia nervosa may have long-term effects on overall and reproductive health. We studied predictors of self-reported eating disorders and associations with later health events. We estimated odds ratios (ORs) for these associations in 47,759 participants from the Sister Study. Two percent (n = 967) of participants reported a history of an eating disorder. Risk factors included being non-Hispanic white, having well-educated parents, recent birth cohort (OR = 2.16, 95% confidence interval [CI]: 2.01–2.32 per decade), and having a sister with an eating disorder (OR = 3.68, CI: 1.92–7.02). As adults, women who had experienced eating disorders were more likely to smoke, to be underweight, to have had depression, to have had a later first birth, to have experienced bleeding or nausea during pregnancy, or to have had a miscarriage or induced abortion. In this descriptive analysis, we identified predictors of and possible long-term health consequences of eating disorders. Eating disorders may have become more common over time. Interventions should focus on prevention and mitigation of long-term adverse health effects.

Bulimia: A Literature Review

This article provides a literature review of bulimia. It examines the condition and its prevalence, features and complications.

Do eating disorders in parents predict eating disorders in children? Evidence from a Swedish cohort

OBJECTIVE

We investigated whether parental eating disorders (ED) predict ED in children, using a large multigeneration register-based sample.

METHOD

We used a subset of the Stockholm Youth Cohort born 1984-1995 and resident in Stockholm County in 2001-2007 (N = 286,232), The exposure was a diagnosed eating disorder in a parent; the outcome was any eating disorder diagnosis in their offspring, given by a specialist clinician, or inferred from an appointment at a specialist eating disorder clinic. A final study sample of 158,697 (55.4%) had data on these variables and confounding factors and contributed a total of 886,241 person years to the analysis.

RESULTS

We found good evidence in support of the hypothesis that ED in either parent are independently associated with ED in their female children (HR 1.97 (95% CI: 1.17-3.33), P = 0.01) and that ED in mothers are independently associated with ED in their female children (HR 2.35 (95% CI: 1.39-3.97) P = 0.001). Numbers were too low to permit separate analysis of ED in parents and their male children.

CONCLUSION

Eating disorders in parents were associated with ED in children. This study adds to our knowledge about the intergenerational transmission of ED, which will help identify high-risk groups and brings about the possibility of targeted prevention.

A nation-wide study of the family aggregation and risk factors in anorexia nervosa over three generations

OBJECTIVE

This nation-wide register-based study investigated how often anorexia nervosa (AN) and co-morbid disorders occur in affected families compared with control families. Furthermore, the study addressed the impact of sex, year of birth, and degree of urbanization in terms of risk factors.

METHOD

A total of N = 2,370 child and adolescent psychiatric subjects born between 1951 and 1996 and registered in the Danish Psychiatric Central Research Register (DPCRR) had any mental disorder before the age of 18 and developed AN at some point during their life-time. In addition, N = 7,035 controls without any psychiatric diagnosis before age 18 and matched for age, sex, and residential region were included. Psychiatric diagnoses were also obtained on the first-degree relatives as a part of the Danish Three Generation Study (3GS). A family load component was obtained by using various mixed regression models.

RESULTS

AN occurred significantly more often in case than in control families. AN Risk factors included having a sibling with AN, affective disorders in family members, and co-morbid affective, anxiety, obsessive-compulsive, personality, or substance use disorders. Furthermore, female sex, and ascending year of birth were significantly associated with having AN. Urbanization was not related to the family load of AN and case-relatives did not develop AN earlier than control relatives.

DISCUSSION

These findings based on a very large and representative dataset provide evidence for the family aggregation and further risk factors in AN.

Eating Disorders: From Twin Studies to Candidate Genes and Beyond

Substantial effort has been put into the exploration of the biological background of eating disorders, through family, twin and molecular genetic studies. Family studies have shown that anorexia (AN) and bulimia nervosa (BN) are strongly familial, and that familial etiologic factors appear to be shared by both disorders. Twin studies often focus on broader phenotypes or subthreshold eating disorders. These studies consistently yielded moderate to substantial heritabilities. In addition, there has been a proliferation of molecular genetic studies that focused on Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV; American Psychiatric Association, 1994) AN and BN. Seven linkage regions have been identified in genome-wide screens. Many genetic association studies have been performed, but no consistent association between a candidate gene and AN or BN has been reported. Larger genetic association studies and collaborations are needed to examine the involvement of several candidate genes and biological pathways in eating disorders. In addition, twin studies should be designed to assist the molecular work by further exploring genetic determinants of endophenotypes, evaluating the magnitude of contribution to liability of measured genotypes as well as environmental risk factors related to eating disorders. In this manner twin and molecular studies can move the field forward in a mutually informative way.

Contemporary thinking about the role of genes and environment in eating disorders

Objective – To review recent literature documenting how family, twin and molecular genetic studies of eating disorders have revolutionized our conceptualizations of anorexia and bulimia nervosa. Methods – We summarized extant litera-ture on genetic epidemiology of eating disorders. Results – Results of extant studies highlight the underlying biological vulnera- bilities associated with these conditions. Genetic research has also opened up new avenues and approaches for exploring how the environment exerts its influence on risk. Conclusions – We discuss state-of-the-science findings in the genetics of eating disorders, explore various mechanisms of gene-environment interplay, and discuss implications of this research for science, practice, families and individuals with eating disorders.

Comorbidity and age of onset of eating disorders in gay men, lesbians, and bisexuals

This study examines the prevalence of psychiatric disorders among lesbian, gay, and bisexual (LGB) men with eating disorders. A total of 388 white, black, and Latino LGB men and women were sampled from community venues. Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) diagnoses of anorexia, bulimia, and binge eating disorder were assessed using the World Health Organization's Composite International Diagnostic Interview. Gay and bisexual men with eating disorders were more likely to have an anxiety or substance abuse disorder than gay and bisexual men without eating disorders, whereas lesbian and bisexual women with eating disorders were more likely to have a mood disorder than lesbian and bisexual women without an eating disorder. For individuals diagnosed with an eating and anxiety or major depressive disorder, the onset of the psychiatric disorder was more likely to precede the onset of the eating disorder. Researchers should study potential explanations of the relationship between eating and psychiatric disorders among LGB men and women.

An introduction to eating disorders: clinical presentation, epidemiology, and prognosis

The spectrum of eating disorders varies widely, ranging from mildly abnormal eating habits to life-threatening chronic disease. Given the many different cultural food norms and individual preferences, along with the fact that dieting behavior is extremely common, it can be challenging to differentiate unusual eating behaviors from clinically significant eating disorders. In this article, the authors provide an introduction to eating disorders including anorexia nervosa, bulimia nervosa, and eating disorders not otherwise specified, focusing on the clinical presentation, epidemiology, and prognosis.

The heritability of eating disorders: methods and current findings

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 era.

The relationship of bulimia and anorexia nervosa with bipolar disorder and its temperamental foundations

BACKGROUND

Earlier studies have suggested a relationship between bipolar disorder (BP) and eating disorders (ED), more specifically, bulimia nervosa (BN) and bipolar II disorder (BP-II). In the present report we extend this relationship to broader definitions of bipolarity.

METHODS

Semi-structured interview of 201 patients with DSM-IV criteria for major affective disorders combined with Akiskal and Mallya criteria for Affective temperaments. To diagnose lifetime comorbid eating disorders DSM-IV criteria for eating disorders (Bulimia Nervosa, BN, Anorexia, AN) were used.

RESULTS

33 patients had an eating disorder. When compared to patients without ED the patients with ED had a higher prevalence of bipolar disorders. Using strict DSM-IV criteria, this association was only significant for BN (OR) 4.5 (95% CI 1.1-17.6). When using a broader index of bipolarity including patients having affective temperaments, a significant relation was found for BN (OR) 9.1 (95% CI 1.1-73.6), and for patients with a lifetime history of both BN and AN (OR) 8.6 (95% CI 1.1-70.2).We also found patients with ED to have a significantly higher prevalence of affective temperaments, an earlier onset of major affective disorder and to have more depressive episodes.

LIMITATIONS

Non-blind evaluation of diagnosis for mood, eating disorders and affective temperaments.

CONCLUSION

In line with previous reports we describe an association between bulimia nervosa and bipolar disorder. Furthermore we report a relationship between lifetime bulimia and anorexia and cyclothymic and related affective temperaments.

Environmental and genetic risk factors for eating disorders: What the clinician needs to know

Patients and families often are aware of research on genetic factors influencing eating disorders. Accurate interpretations of research on environmental and genetic risk factors can be empowering to patients and families; however, misinterpretations could prove detrimental. Clinicians who are not versed in genetic research may believe they are ill prepared to discuss the nuances of genetic research with patients and families. In this article the authors discuss what is known about genetic and environmental risk factors with an emphasis on gene-environment interplay to improve clinicians' comfort level in discussing these complex issues with their patients.

A structural approach to the familial coaggregation of disorders

The demonstration that 2 disorders coaggregate in families is often the first step in the exploration of genetic factors common to the 2 disorders. Previous methods of analyzing familial coaggregation have used either (1) a typical measure of association (eg, the odds ratio) between a disorder in an individual and another disorder in family members, or (2) a linear structural equation model (SEM). The association method accommodates case-control sampling of families, but may not assess the causal effect of interest because it is not based on an underlying causal model. The SEM method is based on a causal model, but cannot easily accommodate case-control sampling or direct effects of 1 disorder on the other within individuals. We develop a new method of analyzing coaggregation based on directed acyclic graphs. Because this method is a generalization of structural equation models and uses measures of association that accommodate case-control sampling and direct effects, it combines the strengths of both previous methods. In the absence of direct effects between disorders, our approach provides a valid estimate of the causal coaggregation effect. In the presence of direct effects, our approach provides an upper-bound estimate and (assuming additive linear effects of latent familial and nonfamilial factors) a lower-bound estimate of the causal coaggregation effect. For illustration, we applied our method to a family study of binge eating disorder and bipolar disorder.

Schmidt M, Poustka F. Psychiatrische Erkrankungen bei Verwandten von Patienten mit Anorexia nervosa und Bulimia nervosa

Zusammenfassung: Fragestellung: Im deutschen Raum gibt es kaum Familienuntersuchungen von Patienten mit Anorexia und Bulimia nervosa. Methodik: In einer Multizenter Studie wurde das Auftreten psychiatrischer Erkrankungen bei Familienangehörigen 1., 2. und 3. Grades von 65 anorektischen (n = 746) und 21 bulimischen Patienten (n = 265) mit denen von 37 gesunden Kontrollen (n = 480) sowie 11 depressiven Patienten (n = 157) verglichen. Messinstrumente waren u.a. das Diagnostische Interview für Genetische Studien bzw. das Familien Interview für Genetische Studien. Ergebnisse: Die Prävalenz von Anorexia nervosa (signifikant) sowie von depressiven Störungen (Trend) war bei Verwandten 1. und 2. Grades von Patienten mit Essstörungen gegenüber der gesunden Gruppe erhöht. Die meisten Ergebnisse waren eher bei den Familien bulimischer Patienten ausgeprägt. Die Prävalenzraten für psychiatrische Erkrankungen waren insgesamt prozentual niedriger als in vergleichbaren US amerikanischen Stichproben. Schlussfolgerung: Die Ergebnisse könnten für eine familiäre Vulnerabilität bzw. genetisches Risiko von Patienten mit Anorexia und Bulimia nervosa sprechen. Der Zusammenhang des niedrigen Alters der Indexpatienten auf die geringeren Prävalenzraten wird diskutiert.

Parental psychopathology as a predictor of long-term outcome in bulimia nervosa patients

This paper sought to examine parental variables as predictors of long-term outcome in women with bulimia nervosa (BN). Participants were 94 treatment-seeking women with BN who were assessed at baseline, treatment end, and at follow-up (M=10.13 years). Participants reported rates of psychopathology and obesity in their mothers and fathers at baseline. The most frequently reported parental psychopathology was substance abuse in fathers. Chi-square analyses indicated that substance abuse in fathers was associated with poor treatment-end outcome in BN participants. Depression in mothers was associated with poor outcome at long-term follow-up, and obesity in mothers was associated with better outcome at long-term follow-up. A logistic regression analysis found that lifetime mood disorder in participants and severe depression in mothers were independent predictors of bulimic symptoms at long-term follow-up. The association between maternal severe depression and long-term outcome in BN suggests that specific parental variables may indicate longer course of BN.

Neurobiology of addiction. An integrative review

Evidence that psychoactive substance use disorders, bulimia nervosa, pathological gambling, and sexual addiction share an underlying biopsychological process is summarized. Definitions are offered for addiction and addictive process, the latter being the proposed designation for the underlying biopsychological process that addictive disorders are hypothesized to share. The addictive process is introduced as an interaction of impairments in three functional systems: motivation-reward, affect regulation, and behavioral inhibition. An integrative review of the literature that addresses the neurobiology of addiction is then presented, organized according to the three functional systems that constitute the addictive process. The review is directed toward identifying candidate neurochemical substrates for the impairments in motivation-reward, affect regulation, and behavioral inhibition that could contribute to an addictive process.

Comorbidity studies of eating disorders and mood disorders. Critical review of the literature

OBJECTIVE

We conducted a critical literature review of studies assessing the prevalence of mood disorders (MD) in subjects with eating disorders (ED; anorexia nervosa and bulimia nervosa). In the first part of this article, we discuss methodological issues relevant to comorbidity studies between ED and MD. In the second part, we summarize the findings of these studies in light of the methodological considerations raised.

METHOD

A manual computerised search (Medline) was performed for all published studies on comorbidity between ED and MD. In order to have sufficiently homogeneous diagnostic criteria for both categories of disorders, this search was limited to articles published between 1985 and 2006.

RESULTS

Too few studies include control groups, few studies compared diagnostic subgroups of ED subjects, and results are scarce or conflicting.

DISCUSSION

The results are discussed in the light of the methodological problems observed. The implications when reviewing the results of published studies and planning future research are set out.

Comorbidity of eating disorders with bipolar disorder and treatment implications

OBJECTIVES

To review the scientific evidence examining the comorbidity among eating disorders and bipolar disorder (BD).

METHODS

We reviewed all published English-language studies addressing the comorbidity of anorexia nervosa, bulimia, bulimia nervosa, and binge eating disorder in patients with BD and studies of comorbidity of BD in patients with eating disorders. In addition, we discuss the pharmacologic treatment implications from reviewed studies of agents used in BD and eating disorders.

RESULTS

Community and clinical population studies of the lifetime prevalence rates of eating disorders in patients with BD, and of BD in patients with eating disorders, particularly when subthreshold and spectrum manifestations of these disorders are included, indicate high rates of comorbidity among these illnesses.

CONCLUSIONS

Pharmacologic treatment approaches to patients with BD and a co-occurring eating disorder require examination of the possible adverse effects of the treatment of each syndrome on the other and attempts to manage both syndromes with agents that might be beneficial to both.

Genetics in eating disorders: extending the boundaries of research

OBJECTIVE: To review the recent literature relevant to genetic research in eating disorders and to discuss unique issues which are crucial for the development of a genetic research project in eating disorders in Brazil. METHOD: A computer literature review was conducted in the Medline database between 1984 and may 2005 with the search terms "eating disorders", "anorexia nervosa", "bulimia nervosa", "binge eating disorder", "family", "twin" and "molecular genetic" studies. RESULTS: Current research findings suggest a substantial influence of genetic factors on the liability to anorexia nervosa and bulimia nervosa. Genetic research with admixed populations should take into consideration sample size, density of genotyping and population stratification. Through admixture mapping it is possible to study the genetic structure of admixed human populations to localize genes that underlie ethnic variation in diseases or traits of interest. CONCLUSIONS: The development of a major collaborative genetics initiative of eating disorders in Brazil and South America would represent a realistic possibility of studying the genetics of eating disorders in the context of inter ethnic groups, and also integrate a new perspective on the biological etiology of eating disorders.

[Comorbidity between eating disorders and mood disorders: review]

OBJECTIVE

Comorbidity between eating disorders (ED) and mood disorders is a major issue when evaluating and treating patients with anorexia nervosa (AN) or bulimia nervosa (BN). In the literature, estimated comorbidity rates of mood disorders in subjects with ED differ widely across studies. Obviously, it is difficult to compare results from various sources because of differences in methods of assessment of depressive symptoms and in diagnostic criteria for both ED and mood disorders. Furthermore, few studies have included control groups, and, since mood disorders are among the most frequent psychiatric disorders in women--with an average estimated lifetime prevalence of 23.9 % (Kessleret al., 1994)--, it is not clear, yet, whether mood disorders are more common among women with an ED (AN or BN) than among women from the community. The only review articles we found on the relationships between ED and mood disorders survey different types of arguments in favour of a link between both categories of disorders, including symptoms, personal and family comorbidity, overlap in biological findings, and treatment results, but do not review in detail available comorbidity data. The aim of this paper is to conduct a critical literature review on studies assessing the prevalence of mood disorders in subjects with an ED (AN or BN). In the first part, we will discuss methodological issues relevant to comorbidity studies between ED and mood disorders, and select the most reliable studies. In the second part, taking into account these methodological considerations raised, we summarize the findings of these studies.

METHOD

We performed a manual and computerized search (Medline) for all published studies on comorbidity between ED and AD, limiting our search to the 1985-2002 period, in order to get sufficiently homogeneous diagnostic criteria for both categories of disorders.

RESULTS

Too few studies include control groups and few studies have compared diagnostic subgroups of ED subjects, with scarce or conflicting results.

DISCUSSION

We reviewed numerous studies here and conclude simply that there are many arguments in favor of elevated rates of MD in ED subjects, but there is no convincing evidence yet. Many questions are left unanswered or have conflicting responses. Our review highlights the need for further studies, which should address several requisites: comorbidity studies should be designed with this as a specific goal, rather than as a secondary aim within other types of studies (such as treatment studies, follow-up studies, etc.). Kendler et al. (1991) state that individuals with two disorders are more likely to present for treatment than individuals with one, therefore, comorbidity rates (which are not in agreement with a special etiologic relationship between BN and depression) may be exaggerated in clinical population results. New studies should include control subjects, matched (at least) for sex and age with ED subjects. Studies should evaluate prevalence of all types of MD in order to yield comparable estimates of MD in general. Comorbidity studies should be conducted on both current and recovered patients, compared to subjects from the community. It is still necessary to demonstrate specificity of findings, i.e. that early onset MD are of specific etiological importance to ED and do not simply increase the risk of later psychopathology in general. Studies should be conducted on larger samples, and all diagnostic subgroups should be considered (restrictive and bulimic anorexics, bulimics with and without history of AN, with or without purging). Multivariate comparisons should be performed, taking into account subject age, sex (if men are included), in- and outpatient status, course of illness, and other possibly relevant variables. Thus, more reliable estimates of the frequency of MD in subjects with ED could provide us with valuable etiologic, therapeutic and prognostic information.

Eating disorders and personality: A methodological and empirical review

Methodological approaches utilized to evaluate models of the relationship between personality and eating disorders, as well as empirical support for each model, are reviewed. Limited prospective research suggests that negative emotionality, perfectionism, drive for thinness, poor interoceptive awareness, ineffectiveness, and obsessive-compulsive personality traits are likely predisposing factors. Limited family study research suggests that obsessive-compulsive personality disorder (OCPD) and anorexia nervosa share a common familial liability. Potential pathoplastic personality factors include Cluster B personality disorders and OCPD, which predict a poorer course and/or outcome, and histrionic personality traits and self-directedness, which predict a more favorable course and/or outcome. Future research should focus upon sophisticated prospective and family study research in order to best evaluate competing models of the eating disorder-personality relationship.

Childhood body-focused behaviors and social behaviors as risk factors of eating disorders

BACKGROUND

The risk factors for adolescent eating disorders are poorly understood. It is generally agreed, however, that interactions with one's body and interactions with others are two important features in the development of anorexia and bulimia nervosa. Therefore, we assessed a variety of childhood body-focused behaviors and childhood social behaviors in eating-disordered patients as compared to non-eating-disordered subjects.

METHOD

We compared 50 female inpatients with eating disorders (anorexia or bulimia nervosa), 50 female inpatients with polysubstance dependence, and 50 nonpatient female control subjects with no history of eating or substance abuse disorders (all defined by DSM-IV criteria), using a semi-structured interview of our own design. We asked questions about (1) childhood body-focused behaviors (e.g. thumb-sucking) and body-focused family experiences (e.g. bodily caresses), and (2) childhood social behaviors (e.g. numbers of close friends) and family social styles (e.g. authoritarian upbringing).

RESULTS

Many body-focused measures, such as feeding problems, auto-aggressive behavior, lack of maternal caresses, and family taboos regarding nudity and sexuality, characterized eating-disordered patients as opposed to both comparison groups, as did several social behaviors, such as adjustment problems at school and lack of close friends. However, nail-biting, insecure parental bonding, and childhood physical and sexual abuse were equally elevated in both psychiatric groups.

CONCLUSION

It appears that eating-disordered patients, as compared to substance-dependent patients and healthy controls, show a distinct pattern of body-focused and social behaviors during childhood, characterized by self-harm, a rigid and 'body-denying' family climate, and lack of intimacy.

Anorexia nervosa: definition, epidemiology, and cycle of risk

Anorexia nervosa is a debilitating psychiatric disorder with profound biological, psychological, and social consequences. After an initial evaluation of the most widely used diagnostic criteria for anorexia nervosa, this paper reviews genetic and environmental risk factors for the development of anorexia with special emphasis on gene environment interplay and the impact of adverse perinatal events.

Comorbidity of bipolar and eating disorders: distinct or related disorders with shared dysregulations?

BACKGROUND

The co-occurrence of bipolar and eating disorders, though of major clinical and public health importance, remains relatively unexamined.

METHODS

In reviewing the literature on this comorbidity, we compared bulimia, anorexia nervosa, bulimia nervosa, binge eating disorders and bipolar disorders on phenomenology, course, family history, biology, and treatment response.

RESULTS

Epidemiological studies show an association between subthreshold bipolar disorder and eating disorders in adolescents, and between hypomania and eating disorders, especially binge eating behavior, in adults. Of the clinical studies, most show that patients with bipolar disorder have elevated rates of eating disorders, and vice versa. Finally, the phenomenology, course, comorbidity, family history, and pharmacologic treatment response of these disorders show considerable overlap on all of these parameters. In particular, on phenomenologic grounds--eating dysregulation, mood dysregulation, impulsivity and compulsivity, craving for activity and/or exercise--we find many parallels between bipolar and eating disorders. Overall, the similarities between these disorders were more apparent when examined in their spectrum rather than full-blown expressions.

LIMITATIONS

Despite an extensive literature on each of these disorders, studies examining their overlap across all these parameters are relatively sparse and insufficiently systematic.

CONCLUSIONS

Nonetheless, the reviewed literature leaves little doubt that bipolar and eating disorders--particularly bulimia nervosa and bipolar II disorder--are related. Although several antidepressants and mood stabilizers have shown promise for eating disorders, their clinical use when these disorders co-exist with bipolarity is still very much of an art. We trust that this review will stimulate more rigorous research in their shared putative underlying psychobiologic mechanisms which, in turn, could lead to more rational targeted treatments.

Residual neuropsychological effects of illicit 3,4-methylenedioxymethamphetamine (MDMA) in individuals with minimal exposure to other drugs

BACKGROUND

A substantial literature suggests that users of illicit 3,4-methylenedioxymethamphetamine (MDMA or "ecstasy") display residual cognitive deficits. Most MDMA users, however, use other illicit drugs as well, so it is difficult to be certain that these deficits are due to MDMA, as opposed to other drug use or additional confounding factors.

METHODS

We administered a battery of neuropsychological tests to 23 young MDMA users who reported minimal exposure to any other drugs, including alcohol, and to 16 comparison individuals equally involved with the rave subculture, but reporting no MDMA use. We compared the groups by regression analyses adjusting for numerous potentially confounding variables. To test for a possible dose-response effect, we also performed a median split of 12 moderate MDMA users (22-50 lifetime uses) and 11 heavy users (60-450 uses), and compared these subgroups with non-users.

RESULTS

MDMA users as a whole performed worse than non-users on most test measures, but these comparisons rarely reached statistical significance. This picture changed markedly in the subgroup analysis: although moderate users displayed virtually no differences from non-users on any measures, the heavy users displayed significant deficits on many measures, particularly those associated with mental processing speed and impulsivity. These differences did not appear explainable by differences in family-of-origin variables, verbal IQ, levels of depression, or time since last MDMA use.

CONCLUSIONS

The presence of residual cognitive deficits, even among unusually "pure" frequent users of illicit MDMA, analyzed with adjustment for confounding variables, augments the evidence that MDMA itself, rather than some associated factor, is responsible for the deficits observed.

Genetics in eating disorders: state of the science

Eating disorders have been viewed as psychiatric illnesses that are strongly influenced by societal pressures towards thinness and attractiveness. Although the environmental context of these disorders must not be neglected, recent research in the area of genetic epidemiology suggests a substantial influence of genetic factors on liability to eating disorders. This review presents a synthesis of current knowledge about genetic factors implicated in the etiology of eating disorders.

Disordered eating and substance use in an epidemiological sample: II. Associations within families

This study investigated familial associations of disordered eating (DE) with substance use and substance use disorders (SU/SUDs) in a community-based sample of 620 adolescent girls, their 310 mothers, and 299 fathers. Female participants completed structured interviews of lifetime anorexia nervosa, bulimia nervosa, binge eating disorder, and SU/SUD; daughters also completed a self-report measure of current DE attitudes and behaviors. Fathers completed interviews assessing lifetime SUD. Evaluation of independent and combined associations of mothers' bulimic eating disturbance (ED) and parents' SUDs with daughters' DE/EDs and SU/SUDs revealed links between mothers' ED and daughters' DE but no relationship between EDs and SU/SUDs across generations. These results suggest that these problems are not cross-transmitted within families and suggest that the addiction model of eating disorders may be simplistic.

Regression methods for assessing familial aggregation of disease

This paper reviews methods for assessing familial aggregation of disease based on simple logistic regression models. Studies are based on a case-control sampling design, where the disease status of the first degree relatives of both cases and controls are obtained. Both 'proband predictive' and 'family predictive' models are discussed, and an example is given using a case-control sample from a lung cancer study in non-smokers. The methods are extended to characterize co-aggregation of two disorders, that is, presence of one disorder in the proband increases the risk of a second disorder in the relative. An example involving eating disorders and depression is given.

Early-onset cannabis use and cognitive deficits: what is the nature of the association?

BACKGROUND

Individuals who initiate cannabis use at an early age, when the brain is still developing, might be more vulnerable to lasting neuropsychological deficits than individuals who begin use later in life.

METHODS

We analyzed neuropsychological test results from 122 long-term heavy cannabis users and 87 comparison subjects with minimal cannabis exposure, all of whom had undergone a 28-day period of abstinence from cannabis, monitored by daily or every-other-day observed urine samples. We compared early-onset cannabis users with late-onset users and with controls, using linear regression controlling for age, sex, ethnicity, and attributes of family of origin.

RESULTS

The 69 early-onset users (who began smoking before age 17) differed significantly from both the 53 late-onset users (who began smoking at age 17 or later) and from the 87 controls on several measures, most notably verbal IQ (VIQ). Few differences were found between late-onset users and controls on the test battery. However, when we adjusted for VIQ, virtually all differences between early-onset users and controls on test measures ceased to be significant.

CONCLUSIONS

Early-onset cannabis users exhibit poorer cognitive performance than late-onset users or control subjects, especially in VIQ, but the cause of this difference cannot be determined from our data. The difference may reflect (1). innate differences between groups in cognitive ability, antedating first cannabis use; (2). an actual neurotoxic effect of cannabis on the developing brain; or (3). poorer learning of conventional cognitive skills by young cannabis users who have eschewed academics and diverged from the mainstream culture.

Etiologia dos transtornos alimentares: aspectos biológicos, psicológicos e sócio-culturais

Os transtornos alimentares possuem uma etiologia multifatorial, composta de predisposições genéticas, socioculturais e vulnerabilidades biológicas e psicológicas. Entre os fatores predisponentes, destacam-se a história de transtorno alimentar e (ou) transtorno do humor na família, os padrões de interação presentes no ambiente familiar, o contexto sociocultural, caracterizado pela extrema valorização do corpo magro, disfunções no metabolismo das monoaminas centrais e traços de personalidade. A dieta é o comportamento precursor que geralmente antecede a instalação de um transtorno alimentar. Contudo, a presença isolada da dieta não é suficiente para desencadear o transtorno alimentar, tornando-se necessária uma interação entre os fatores de risco e outros eventos precipitantes. Por último, o curso transitório ou crônico de um transtorno alimentar está relacionado à persistência de distorções cognitivas, à ocorrência de eventos vitais significativos e a alterações secundárias ao estado de desnutrição.

Cognitive measures in long-term cannabis users

The cognitive effects of long-term cannabis use are insufficiently understood. Most studies concur that cognitive deficits persist at least several days after stopping heavy cannabis use. But studies differ on whether such deficits persist long term or whether they are correlated with increasing duration of lifetime cannabis use. The authors administered neuropsychological tests to 77 current heavy cannabis users who had smoked cannabis at least 5000 times in their lives, and to 87 control subjects who had smoked no more than 50 times in their lives. The heavy smokers showed deficits on memory of word lists on Days 0, 1, and 7 of a supervised abstinence period. By Day 28, however, few significant differences were found between users and controls on the test measures, and there were few significant associations between total lifetime cannabis consumption and test performance. Although these findings may be affected by residual confounding, as in all retrospective studies, they suggest that cannabis-associated cognitive deficits are reversible and related to recent cannabis exposure rather than irreversible and related to cumulative lifetime use.

Characteristics of bulimic patients whose parents do or do not abuse alcohol

OBJECTIVES

This study attempts to understand the effects of a parental history of alcohol abuse on the psychopathology and symptoms of bulimia nervosa (BN).

METHOD

The study involved 121 female BN patients consecutively admitted to the Eating Disorders Unit of the University Hospital of Bellvitge. The sample was divided post hoc into two subgroups on the basis of the presence (PAA, n=25) or not of parental abuse of alcohol (NPAA, n=96). All of the patients fulfilled the DSM-IV criteria for BN.

EVALUATION

The assessment measures were the Eating Attitudes Test (EAT-40), the Eating Disorders Inventory (EDI), the Bulimic Investigatory Test Edinburgh (BITE), the Body Shape Questionnaire (BSQ) and Beck Depression Inventory (BDI), as well as clinical and psychopathological variables.

RESULTS AND CONCLUSIONS

Only 7.4% of the patients reported current alcohol abuse and this correlated positively with the presence of other impulsive behaviours (p<0.001). Furthermore, PAA was observed in 20.7% of cases. When the PAA and NPAA subgroups were compared, no significant differences were found in the symptomatological or psychopathological variables, but the PAA group showed more frequent parental obesity (p<0.001) and its members lived less frequently with their parents (p<0.001). The results of this study suggest that there is little correlation between parental abuse of alcohol and the severity of BN.

Eating disorders and childbearing: concealment and consequences

The reported incidence of eating disorders has increased markedly during the past 30 years. Numerous studies have linked a spectrum of eating disorders to serious medical complications resulting in hospitalization and death. The prevalence of such disorders occurs primarily in women of adolescent and childbearing age. This article reviews the published literature alerting the practitioner to the indicators of a condition that is seldom disclosed bythe client or detected by the caregiver. Predisposing factors, behavioral theories, and reproductive outcomes are discussed to provide clear evidence of the link between eating disorders and poor pregnancy outcome. Recommendations are offered for early recognition ofa repeatedly concealed disease and for management of eating disorders during the childbearing cycle.

Eating disorders in adolescents and young adults

Adolescence and young adulthood mark the convergence of substantial biologic and social change. Individuals differ in their innate capacity to tolerate change. Research suggests that some of the personality characteristics that are fundamental to individuals with eating disorders may render them particularly vulnerable to the impact of a changing body and changing social demands. The fact that eating disorders emerge primarily during adolescence and often run a protracted course can deprive the afflicted individual of the core social, emotional, and biologic developmental processes that normally occur during this time of life.

Evidence for a susceptibility gene for anorexia nervosa on chromosome 1

Eating disorders, such as anorexia nervosa (AN), have a significant genetic component. In the current study, a genomewide linkage analysis of 192 families with at least one affected relative pair with AN and related eating disorders, including bulimia nervosa, was performed, resulting in only modest evidence for linkage, with the highest nonparametric linkage (NPL) score, 1.80, at marker D4S2367 on chromosome 4. Since the reduction of sample heterogeneity would increase power to detect linkage, we performed linkage analysis in a subset (n=37) of families in which at least two affected relatives had diagnoses of restricting AN, a clinically defined subtype of AN characterized by severe limitation of food intake without the presence of binge-eating or purging behavior. When we limited the linkage analysis to this clinically more homogeneous subgroup, the highest multipoint NPL score observed was 3.03, at marker D1S3721 on chromosome 1p. The genotyping of additional markers in this region led to a peak multipoint NPL score of 3.45, thereby providing suggestive evidence for the presence of an AN-susceptibility locus on chromosome 1p.

Multivariate logistic regression for familial aggregation of two disorders. II. Analysis of studies of eating and mood disorders

Family studies have suggested that eating disorders and mood disorders may coaggregate within families. Previous studies, however, have been limited by use of univariate modeling techniques and failure to account for the correlation of observations within families. To provide a more efficient analysis and to illustrate multivariate logistic regression models for familial aggregation of two disorders, the authors analyzed pooled data from two previously published family studies (conducted in Massachusetts in 1984-1986 and 1986-1987) by using multivariate proband predictive and family predictive models. Both models demonstrated a significant familial aggregation of mood disorders and familial coaggregation of eating and mood disorders. The magnitude of the coaggregation between eating and mood disorders was similar to that of the aggregation of mood disorders. Similar results were obtained with alternative models, including a traditional univariate proband predictive model. In comparison with the univariate model, the multivariate models provided greater flexibility, improved precision, and wider generality for interpreting aggregation effects.

Multivariate logistic regression for familial aggregation of two disorders. I. Development of models and methods

The question of whether two disorders cluster together, or coaggregate, within families often arises. This paper considers how to analyze familial aggregation of two disorders and presents two multivariate logistic regression methods that model both disorder outcomes simultaneously. The first, a proband predictive model, predicts a relative's outcomes (the presence or absence of each of the two disorders) by using the proband's disorder status. The second, a family predictive model derived from the quadratic exponential model, predicts a family member's outcomes by using all of the remaining family members' disorder statuses. The models are more realistic, flexible, and powerful than univariate models. Methods for estimation and testing account for the correlation of outcomes among family members and can be implemented by using commercial software.

Twin studies of eating disorders: a review

OBJECTIVE

Twin methodology has been used to delineate etiological factors in many medical disorders and behavioral traits including eating disorders. Although twin studies are powerful tools, their methodology can be arcane and their implications easily misinterpreted.

METHOD

The goals of this study are to (a) review the theoretical rationale for twin studies; (b) provide a framework for their interpretation and evaluation; (c) review extant twin studies on eating disorders; and (d) explore the implications for understanding etiological issues in eating disorders.

DISCUSSION

On the basis of this review, it is not possible to draw firm conclusions regarding the precise contribution of genetic and environmental factors to anorexia nervosa. Twin studies confirm that bulimia nervosa is familial and reveal significant contributions of additive genetic effects and of unique environmental factors in liability to bulimia nervosa. The magnitude of the contribution of shared environment is less clear, but in the studies with the greatest statistical power, it appears to be less prominent than additive genetic factors.

Familial aggregation of eating disorders: results from a controlled family study of bulimia nervosa

OBJECTIVE

While familial aggregation of bulimia nervosa (BN) is known to occur, the extent to which aggregation of a broader spectrum of eating disorders (ED) occurs in the families of individuals with BN is less certain.

METHOD

Direct interviews and blind best-estimate diagnostic procedures were used to assess lifetime histories of EDs among first-degree relatives (n = 177) of probands with BN (n = 47) and first-degree relatives (n = 190) of non-ED control probands (n = 44).

RESULTS

Forty-three percent of sisters and 26% of mothers of BN probands had a lifetime ED diagnosis, with eating disorder not otherwise specified (ED-NOS) diagnoses being most common. These rates were significantly higher than among sisters (5%) and mothers (5%) of controls. Few male relatives of either cohort had an ED.

CONCLUSIONS

Diagnostic assessment using contemporary family-epidemiology methodology revealed very strong familial aggregation of a broad spectrum of EDs among female relatives of women with BN.

Specificity of eating disorders diagnoses in families of probands with anorexia nervosa and bulimia nervosa

This study examines the prevalence of anorexia nervosa and bulimia nervosa in relatives of probands, and examines the probandwise specificity of any familial clustering. Data were collected from probands using the family history method. Probands were recruited in a sequential cohort fashion. Information collected from probands was rated semiblindly by two of the authors, and a diagnostic hierarchy applied to arrive at a diagnosis for each of the relatives assessed. Data are reported on 2,125 family members, collected from 93 probands. Diagnostic agreement between raters was high, with serious disagreement present in three of 167 possible cases of an eating disorder. Rates of anorexia nervosa, bulimia nervosa, major depression, and substance abuse declined from first- to third-degree relatives, which is consistent with genetic clustering, and there was evidence of a cohort effect operating for anorexia nervosa and bulimia nervosa. The rates of anorexia nervosa and bulimia nervosa in all family members were 5.1%, and 4.3% respectively. An analysis of maternal and paternal descent showed no evidence for X-linked dominant transmission in these families. Preliminary analysis of the clustering of diagnoses in relatives showed a tendency (chi 2 = 14.47, P = .006) for family members to be affected by the same diagnosis as was the proband. This trend was strongest for anorexia nervosa, but there was overlap when the proband had a lifetime diagnosis of bulimia nervosa, with or without anorexia nervosa. These results are compatible with the existence of genetic factors influencing predisposition to eating disorders, but do not prove such.

Coming alive: the psychotherapeutic treatment of patients with eating disorders

OBJECTIVE

To describe a dynamic psychotherapeutic approach specifically developed for women with eating disorders.

METHOD

The developmental origins and psychological disturbances associated with eating disorders are outlined based on a review of the literature and the authors' observations. Principles from contemporary psychodynamic theories that focus on subjectivity and intersubjectivity are applied to the treatment of women with eating disorders and are illustrated with clinical vignettes. Theoretical models employed include intersubjective and relational theory, self psychology, and feminist psychodynamic theory.

RESULTS

Relative unresponsiveness to a child's subjective experience and to child-initiated cues are thought to contribute to psychological disturbances among women with eating disorders. These disturbances include impairment in the sense of effectiveness, in the capacity to appreciate and tolerate emotions, and in the continuity and cohesiveness of self-experience. Self-imposed starvation, binge-purge episodes, and excessive exercise may act as psychic organizers in women with these vulnerabilities. An active psychotherapeutic approach with sustained interest in the patient's authentic subjective experience promotes the identification, organization, and integration of emotional experience and the consolidation of a more differentiated sense of self.

CONCLUSION

In the psychotherapeutic treatment of women with eating disorders, a therapeutic posture of sustained empathic enquiry contributes to the patient's curiosity about her own subjective world. Feeling understood in a therapeutic relationship and feeling assisted in organizing and understanding one's subjective experience contributes to the gradual unfolding of the psychological sense of self.

Fatigue mood as an indicator discriminating between anorexia nervosa and bulimia nervosa

In order to clarify the differences in mood states between anorexia and bulimia nervosa, the Profile of Mood States (POMS) with tension-anxiety, depression, anger-hostility, vigour, fatigue and confusion scales was administered to 32 female patients with anorexia nervosa (age range 14 to 32 years, mean age 20 years), 49 female patients with bulimia nervosa (age range 15 to 33 years, mean age 23 years) and 410 'normal' female subjects (age range 14 to 35 years, mean age 23 years). The scores on the depression, fatigue and confusion scales for both anorexia and bulimia nervosa and those on the tension-anxiety and anger-hostility scales for bulimia nervosa were significantly higher than those for the control subjects. The score on the fatigue scale for bulimia nervosa was significantly higher than that for anorexia nervosa. Moreover, the result of the multiple logistic regression analysis including all of the POMS scales indicated that the fatigue scale significantly discriminated between the two disorders. Fatigue mood appears to be a principal indicator for differentiating between the two disorders.

Self-directed hostility and family functioning in normal-weight bulimics and overweight binge eaters

The aim of this study was to examine whether overweight binge eaters demonstrate similar perceptions of family interactions and views of the self as do normal-weight bulimics. We compared 37 obese binge eaters and 37 normal-weight bulimics to 38 normal-weight non-bulimic controls, and 10 overweight nonbulimic controls on the Bulimia Test (BULIT). Profile of Mood States (POMS), Structural Analysis of Social Behavior (SASB) Short Form, which includes measure of hostility of family interactions and self-directed hostility; the Family Interaction Survey (FIS), and a measure of history of physical and sexual abuse and familial psychopathology. Both normal-weight bulimics and overweight binge eaters differed from nonbulimic controls across all measures of symptomatology, family functioning, history of abuse, familial psychopathology, and self-directed hostility. Normal-weight bulimics demonstrated significantly higher BULIT scores and self-directed hostility than did overweight binge eaters. Post hoc analysis showed that among binge eaters and bulimics, self-directed hostility accounted for a significant percentage of the variance of BULIT scores when controlling for the effects of age, BMI, family hostility, and mood. The possible role of self-directed hostility in the maintenance of bulimic symptomatology is discussed.

Bulimia nervosa in two cultures: a comparison of Austrian and American college students

We compared 33 college women meeting DSM-III-R criteria for bulimia nervosa, recruited at Leopold Franzens Universität in Innsbruck, Austria, with 33 bulimic women recruited by identical methods at Northeastern University and Boston University in Boston, Massachusetts. Bulimia nervosa showed striking stereotypy across the two cultures. Austrian and American subjects reported similar demographic features, bulimic symptoms, severity and chronicity of illness, associated personal and familial psychiatric disorders, upbringing and family environment, and frequency of childhood sexual abuse. Only two variables, substance abuse and satisfaction with body image, differed markedly between the two groups. These differences appear to represent ambient differences between American and Austrian culture as a whole, rather than specific features of the bulimic syndrome.

Risk factors for bulimia nervosa: a controlled study of parental psychiatric illness and divorce

Twenty five women with normal-weight bulimia nervosa were compared with 25 age- and weight-matched women without bulimia nervosa on measures of parental psychiatric illness. Case and control probands, as well as their parents, completed the Family History Research Diagnostic Criteria (FH-RDC) interview and a battery of self-report instruments. Case probands and controls were divided into two groups based on evidence for parental psychiatric illness. The assignment of parental psychiatric illness was made by (a) a positive parental history of alcoholism or depression from the FH-RDC; or (b) evidence of parental major depression, alcoholism, or personality disorder from the self-report measures. Parental psychiatric illness occurred significantly more frequently for case probands compared to the control probands (64% vs. 24%, odds ratio = 5.6, 95% Cl = 1.7-19.2). Parental psychiatric illness was also associated with parental divorce (Fisher's exact p = .023) and a trend toward lower ratings of paternal but not maternal relationship by case probands. This study suggests parental psychiatric illness may be a risk factor for bulimia nervosa and may contribute to environmental effects through increased rates of divorce and impaired paternal relationships.

Bulimia comorbidity in the general population and in the clinic

This study compares rates of comorbidity of lifetime psychiatric disorder in a clinical sample of women with bulimia, with general population base rates, and with rates of comorbidity among bulimic women in the general population. Eighty-four per cent of the clinical sample of bulimic women had a lifetime affective disorder, and 44% a lifetime alcohol or drug disorder. These rates of disorder were significantly higher than the base rates in the general population. Bulimic women in the general population also had more affective and substance-use disorders than the general population base rates, but the rates of these disorders were lower than found in the clinical sample. In the general population, quite similar rates of other disorders including generalized anxiety, panic, phobia and obsessive-compulsive disorder, are found among those with bulimia, substance-use disorder and depression. Furthermore, among those with depression and substance-use disorder in the general population, rates of eating disorder are comparable. Rather than suggesting a specific relationship between bulimia and either depression or substance-use disorder, the data from this study suggest that the presence of any disorder is associated with a non-specific increase in the likelihood of other psychiatric disorder.

Characteristics of bulimic women with and without alcohol abuse

We compared the characteristics of hospitalized women with bulimia nervosa alone (N = 19) and with bulimia nervosa plus alcohol abuse (N = 13) using standard measures of depression, eating disorders, general psychiatric symptomatology, and temperament. Bulimic women with alcohol abuse had significantly higher lowest past weight, but did not differ from women with bulimia alone on age, age of onset of bulimia, current weight, and highest past weight. There were no differences in clinical symptoms of bulimia, depression, or general psychiatric symptomatology. On Cloninger's Tridimensional Personality Questionnaire (TPQ), bulimic women with alcohol abuse scored significantly higher on Total Novelty Seeking, on the Novelty Seeking Subscale Disorderliness, and on the Reward Dependence Subscale Attachment. Implications for understanding the relation between bulimia and substance abuse are discussed.