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Estimated heritability of educational attainment (EA) varies widely, from 23% to 80%, with growing evidence suggesting the degree to which genetic variation contributes to individual differences in EA is highly dependent upon situational factors. We aimed to decompose EA into influences attributable to genetic propensity and to environmental context and their interplay, while considering influences of rearing household economic status (HES) and sex. We use the Project Talent Twin and Sibling Study, drawn from the population-representative cohort of high school students assessed in 1960 and followed through 2014, to ages 68−72. Data from 3552 twins and siblings from 1741 families were analyzed using multilevel regression and multiple group structural equation models. Individuals from less-advantaged backgrounds had lower EA and less variation. Genetic variance accounted for 51% of the total variance, but within women and men, 40% and 58% of the total variance respectively. Men had stable genetic variance on EA across all HES strata, whereas high HES women showed the same level of genetic influence as men, and lower HES women had constrained genetic influence on EA. Unexpectedly, middle HES women showed the largest constraints in genetic influence on EA. Shared family environment appears to make an outsized contribution to greater variability for women in this middle stratum and whether they pursue more EA. Implications are that without considering early life opportunity, genetic studies on education may mischaracterize sex differences because education reflects different degrees of genetic and environmental influences for women and men.

IntroductionWe evaluated the prevalence of dementia and mild cognitive impairment (MCI) in indigenous Tsimane and Moseten, who lead a subsistence lifestyle.MethodsParticipants from population-based samples ≥60 years of age (n=623) were assessed using adapted versions of the Modified Mini-Mental State Examination, informant interview, longitudinal cognitive testing and brain computed tomography (CT) scans.ResultsTsimane exhibited five cases of dementia (among n=435; crude prevalence=1.2%, 95% confidence interval [CI]: 0.4, 2.7); Moseten exhibited one case (among n=169; crude prevalence=0.6%, 95% CI: 0.0, 3.2), all age≥80 years. Age-standardized MCI prevalence was 7.7% (95% CI: 5.2, 10.3) in Tsimane and 9.8% (95% CI: 4.9, 14.6) in Moseten. Cognitive impairment was associated with visuospatial impairments, parkinsonian symptoms, and vascular calcification in the basal ganglia.DiscussionThe prevalence of dementia in this cohort is among the lowest in the world. Widespread intracranial medial arterial calcifications suggest a previously unrecognized, non-Alzheimer's disease (AD) dementia phenotype.

The National Academy of Sciences-National Research Council (NAS-NRC) Twin Registry is one of the oldest, national population-based twin registries in the USA. It comprises 15,924 White male twin pairs born in the years 1917–1927 (N = 31.848), both of whom served in the armed forces, chiefly during World War II. This article updates activities in this registry since the most recent report in Twin Research and Human Genetics (Page, 2006). Records-based data include information from enlistment charts and Veterans Administration data linkages. There have been three major epidemiologic questionnaires and an education and earnings survey. Separate data collection efforts with the NAS-NRC registry include the National Heart, Lung, and Blood Institute (NHLBI) subsample, the Duke Twins Study of Memory in Aging and a clinically based study of Parkinson’s disease. Progress has been made on consolidating the various data holdings of the NAS-NRC Twin Registry. Data that had been available through the National Academy of Sciences are now freely available through National Archive of Computerized Data on Aging (NACDA).

The Project Talent Twin and Sibling (PTTS) study includes 4481 multiples and their 522 nontwin siblings from 2233 families. The sample was drawn from Project Talent, a U.S. national longitudinal study of 377,000 individuals born 1942–1946, first assessed in 1960 and representative of U.S. students in secondary school (Grades 9–12). In addition to the twins and triplets, the 1960 dataset includes 84,000 siblings from 40,000 other families. This design is both genetically informative and unique in facilitating separation of the ‘common’ environment into three sources of variation: shared by all siblings within a family, specific to twin-pairs, and associated with school/community-level factors. We term this the GIFTS model for genetics, individual, family, twin, and school sources of variance. In our article published in a previous Twin Research and Human Genetics special issue, we described data collections conducted with the full Project Talent sample during 1960–1974, methods for the recent linking of siblings within families, identification of twins, and the design of a 54-year follow-up of the PTTS sample, when participants were 68–72 years old. In the current article, we summarize participation and data available from this 2014 collection, describe our method for assigning zygosity using survey responses and yearbook photographs, illustrate the GIFTS model applied to 1960 vocabulary scores from more than 80,000 adolescent twins, siblings and schoolmates and summarize the next wave of PTTS data collection being conducted as part of the larger Project Talent Aging Study.

In this paper, we summarize the design and measures in Project Talent, describe the Twin and Sibling sample, and present results for cognitive abilities. In most twin and family designs, the ‘shared environment’ includes factors specific to a family as well as between-family differences in macro-level variables such as socioeconomic status, community and geographical region. The school-based sampling design used in Project Talent provides a unique opportunity to partition the shared environment into variation shared by siblings, specific to twins, and associated with school- and community-level factors. We present results from our twin-sib-classmate model applied to cognitive abilities, including memory, abstract reasoning, spatial visualization, math and verbal abilities, and show how these abilities differ in the importance and sources of shared environment. These results address longstanding questions of the role of genetic, early life experiences, individual difference factors, and life course conditions in shaping later-life cognitive and physical well-being.

Objective This study was undertaken to clarify how genetic liability and stressful life events interact in the etiology of major depression. Method Information about stressful life events and onset of major depressive episodes in the past year was collected in a population-based sample of female-female twin pairs including 2,164 individuals, 53,215 person-months of observation, and 492 onsets of depression. Results Nine "personal" and three aggregate "network" stressful events significantly predicted onset of major depression in the month of occurrence, four of which predicted onset with an odds ratio of > 10 and were termed "severe": death of a close relative, assault, serious marital problems, and divorce/breakup. Genetic liability also had a significant impact on risk of onset of depression. For severe stressful events, as well as for 10 of the 12 individual stressful events, the best-fitting model for the joint effect of stressful events and genetic liability on onset of major depression suggested genetic control of sensitivity to the depression-inducing effects of stressful life events. In individuals at lowest genetic risk (monozygotic twin, co-twin unaffected), the probability of onset of major depression per month was predicted to be 0.5% and 6.2%, respectively, for those unexposed and exposed to a severe event. In those at highest genetic risk (monozygotic twin, co-twin affected), these probabilities were 1.1% and 14.6%, respectively. Linear regression analysis indicated significant Genotype by Environment interaction in the prediction of onset of major depression. Conclusions Genetic factors influence the risk of onset of major depression in part by altering the sensitivity of individuals to the depression-inducing effect of stressful life events.

Background. Clinical judgments about the likelihood of suicide attempt would be aided by an index of risk factors that could be quickly assessed in diverse settings. We sought to develop such a risk index for 12-month suicide attempts among suicide ideators.Method. The National Comorbidity Survey Replication (NCS-R), a household survey of adults aged 18+, assessed the 12-month occurrence of suicide ideation, plans and attempts in a subsample of 5692 respondents. Retrospectively assessed correlates include history of prior suicidality, sociodemographics, parental psychopathology and 12-month DSM-IV disorders.Results. Twelve-month prevalence estimates of suicide ideation, plans and attempts are 2·6, 0·7 and 0·4% respectively. Although ideators with a plan are more likely to make an attempt (31·9%) than those without a plan (9·6%), 43% of attempts were described as unplanned. History of prior attempts is the strongest correlate of 12-month attempts. Other significant correlates include shorter duration of ideation, presence of a suicide plan, and several sociodemographic and parental psychopathology variables. Twelve-month disorders are not powerful correlates. A four-category summary index of correlates is strongly related to attempts among ideators [area under the receiver operator characteristic curve (AUC)=0·88]. The distribution (conditional probability of attempt) of the risk index is: 19·0% very low (0·0%), 51·1% low (3·5%), 16·2% intermediate (21·3%), and 13·7% high (78·1%). Two-thirds (67·1%) of attempts were made by ideators in the high-risk category.Conclusions. A short, preliminary risk index based on retrospectively reported responses to fully structured questions is strongly correlated with 12-month suicide attempts among ideators, with a high concentration of attempts among high-risk ideators.

Although the 1990s saw enormous change in the mental health care system in the United States, little is known about changes in the prevalence or rate of treatment of mental disorders.We examined trends in the prevalence and rate of treatment of mental disorders among people 18 to 54 years of age during roughly the past decade. Data from the National Comorbidity Survey (NCS) were obtained in 5388 face-to-face household interviews conducted between 1990 and 1992, and data from the NCS Replication were obtained in 4319 interviews conducted between 2001 and 2003. Anxiety disorders, mood disorders, and substance-abuse disorders that were present during the 12 months before the interview were diagnosed with the use of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV). Treatment for emotional disorders was categorized according to the sector of mental health services: psychiatry services, other mental health services, general medical services, human services, and complementary-alternative medical services.The prevalence of mental disorders did not change during the decade (29.4 percent between 1990 and 1992 and 30.5 percent between 2001 and 2003, P=0.52), but the rate of treatment increased. Among patients with a disorder, 20.3 percent received treatment between 1990 and 1992 and 32.9 percent received treatment between 2001 and 2003 (P0.001). Overall, 12.2 percent of the population 18 to 54 years of age received treatment for emotional disorders between 1990 and 1992 and 20.1 percent between 2001 and 2003 (P0.001). Only about half those who received treatment had disorders that met diagnostic criteria for a mental disorder. Significant increases in the rate of treatment (49.0 percent between 1990 and 1992 and 49.9 percent between 2001 and 2003) were limited to the sectors of general medical services (2.59 times as high in 2001 to 2003 as in 1990 to 1992), psychiatry services (2.17 times as high), and other mental health services (1.59 times as high) and were independent of the severity of the disorder and of the sociodemographic characteristics of the respondents.Despite an increase in the rate of treatment, most patients with a mental disorder did not receive treatment. Continued efforts are needed to obtain data on the effectiveness of treatment in order to increase the use of effective treatments.

The National Comorbidity Survey Replication (NCS‐R) is a survey of the prevalence and correlates of mental disorders in the US that was carried out between February 2001 and April 2003. Interviews were administered face‐to‐face in the homes of respondents, who were selected from a nationally representative multi‐stage clustered area probability sample of households. A total of 9,282 interviews were completed in the main survey and an additional 554 short non‐response interviews were completed with initial non‐respondents. This paper describes the main features of the NCS‐R design and field procedures, including information on fieldwork organization and procedures, sample design, weighting and considerations in the use of design‐based versus model‐based estimation. Empirical information is presented on non‐response bias, design effect, and the trade‐off between bias and efficiency in minimizing total mean‐squared error of estimates by trimming weights. Copyright © 2004 Whurr Publishers Ltd.

An overview is presented of the rationale, design, and analysis plan for the WMH‐CIDI clinical calibration studies. As no clinical gold standard assessment is available for the DSM‐IV disorders assessed in the WMH‐CIDI, we adopted the goal of calibration rather than validation; that is, we asked whether WMH‐CIDI diagnoses are ‘consistent’ with diagnoses based on a state‐of‐the‐art clinical research diagnostic interview (SCID; Structured Clinical Interview for DSM‐IV) rather than whether they are ‘correct’. Consistency is evaluated both at the aggregate level (consistency of WMH‐CIDI and SCID prevalence estimates) and at the individual level (consistency of WMH‐CIDI and SCID diagnostic classifications). Although conventional statistics (sensitivity, specificity, Cohen's κ) are used to describe diagnostic consistency, an argument is made for considering the area under the receiver operator curve (AUC) to be a more useful general‐purpose measure of consistency. In addition, more detailed analyses are used to evaluate consistency on a substantive level. These analyses begin by estimating prediction equations in a clinical calibration subsample, with WMH‐CIDI symptom‐level data used to predict SCID diagnoses, and using the coefficients from these equations to assign predicted probabilities of SCID diagnoses to each respondent in the remainder of the sample. Substantive analyses then investigate whether estimates of prevalence and associations when based on WMH‐CIDI diagnoses are consistent with those based on predicted SCID diagnoses. Multiple imputation is used to adjust estimated standard errors for the imprecision introduced by SCID diagnoses being imputed under a model rather than measured directly. A brief illustration of this approach is presented in comparing the precision of SCID and predicted SCID estimates of prevalence and correlates under varying sample designs. Copyright © 2004 Whurr Publishers Ltd.

Background The prevalence (lifetime, 12-month, 1-month) of mental disorders, their relationship with sociodemographic features, and the use of services were investigated in the population aged 18 years or older living in the catchment area of a large hospital complex in the city of Sao Paulo, Brazil. Methods A community survey was conducted in two boroughs of Sao Paulo, on 1,464 residents aged 18 years or older. The assessment of psychopathology was made by CIDI 1.1, yielding diagnoses according to ICD-10 for mood disorders, anxiety disorders, non-affective psychosis, substance use disorders, dissociative and somatoform disorders, and cognitive impairment. Results Of the total sample, 45.9 % had at least one lifetime diagnosis of mental disorder, 26.8 % in the year, and 22.2 % in the month prior to interview. The most prevalent disorders (lifetime, 12-month, and 1-month, respectively) were: nicotine dependence (25 %, 11.4 %, 9.3 %), any mood disorder (18.5 %, 7.6 %, 5 %) with depressive episode the most prevalent mood disorder (16.8 %, 7.1 %, 4.5 %), any anxiety disorder (12.5 %, 7.7 %, 6 %), somatoform disorder (6 %, 4.2 %, 3.2 %), and alcohol abuse/dependence (5.5 %, 4.5 %, 4 %). No gender differences were found in overall morbidity. Excluding substance use disorders, women had a higher risk for non-psychotic disorders. The presence of psychiatric diagnosis increased the use of services, with a low proportion of subjects seeking specialty mental care. Conclusion Our results confirm the high prevalence of mental disorders in the community, similar to findings in other countries. A comparison with findings from other studies with similar methodology is made.

General population survey data are used to disaggregate the associations of substance use disorders with suicide attempts in order to evaluate a number of hypotheses about the processes leading to these associations. Data are from the US National Comorbidity Survey (1990-1992). Discrete-time survival analysis is used to study the effects of retrospectively reported temporally prior substance use, abuse, and dependence in predicting first onset of suicidal behavior. Alcohol and drug use predict subsequent suicide attempts after controlling for sociodemographics and comorbid mental disorders. Previous use is not a significant predictor among current nonusers. Abuse and dependence are significant predictors among users for three of the 10 substances considered (alcohol, inhalants, and heroin). The number of substances used is more important than the types of substances used in predicting suicidal behavior. Disaggregation shows that the effects of use are largely on suicidal ideation and nonplanned attempts among ideators. In comparison, the effects of use on suicide plans and planned attempts among ideators are not significant. Clinicians need to be aware that current substance use, even in the absence of abuse or dependence, is a significant risk factor for unplanned suicide attempts among ideators.

Fetal alcohol syndrome is often associated with severe physical and neuropsychiatric maldevelopment. On the other hand, some offspring of women who drank during pregnancy appear to be affected in minimal ways and function relatively well within society. We questioned whether this effect of prenatal alcohol in the adult is generally minimal. To bear on this, we determined whether we could distinguish alcohol-exposed from nonexposed individuals in a population of male veterans, selected because of both their accepted level of function within society (e.g., honorable discharge from the military) and their admission to an alcohol treatment unit (thus, a greater likelihood of parental alcoholism, because of its familial aggregation). Consecutively admitted alcoholics (cases; n = 77) with likely maternal alcohol ingestion during their pregnancy or the first 10 years of life were matched with alcoholics with no maternal alcohol exposure during these periods (controls; n = 161). Each subject completed questionnaires regarding personal birthweight, alcohol, drug, educational and work histories, and family (including parental) alcohol and drug histories. We measured height, weight, and head circumference; checked for facial and hand anomalies; and took a frontal facial photograph, from which measurements of features were made. Data were analyzed by univariate statistics and stepwise logistic regression. No case had bona fide fetal alcohol syndrome. With univariate statistical analyses, the cases differed from the controls in 10 variables, including duration of drinking, width of alae nasae, being hyperactive or having a short attention span, and being small at birth. By stepwise logistic regression, the variables marital status, small size at birth, duration of drinking, and the presence of a smooth philtrum were marginally (the first two) or definitely (the last two) significant predictors of case status. Analysis of only the 37 cases in whom maternal prenatal drinking was the most likely yielded a marginal association for small size at birth (odds ratio = 3.1, p = 0.08) and a significant association for the presence of a smooth philtrum (odds ratio = 11.9, p = 0.005). Predictability was poor in all regression models. Based on the presence of this single physical finding (smooth philtrum), we estimate that the prevalence of manifestations of fetal alcohol exposure (fetal alcohol effects) is 6 to 13% in adult male veteran children (not necessarily nonveteran offspring) of women who drank alcohol during pregnancy. Thus, in our study of adult veterans, most individuals who were born to women who drank during pregnancy could not be differentiated from normal individuals, and those who were affected were distinguished by a single, nonspecific physical finding.

The associations of prior DSM-III-R disorders with probability and timing of subsequent divorce were examined.The data came from the part II subsample (N=5,877) of the National Comorbidity Survey. The respondents completed a structured diagnostic interview that retrospectively dated age at onset of each of 14 lifetime DSM-III-R disorders and recorded ages at first marriage and divorce. These data were used to estimate survival models describing the relationships between prior disorders and subsequent divorce. In addition, simulations were used to estimate the number of years spent out of marriage because of these causal relationships in the total U.S. population.Prior psychiatric disorders were associated with a substantially higher risk of divorce. The simulations suggested that the effects of these associations in the U.S. population in the survey's age range are approximately 23 million lost years of marriage among men and 48 million lost years of marriage among women.Psychiatric disorders have a number of adverse consequences for those who suffer from them and for their families and communities. The results reported here suggest that an increase in the number of people who divorce and a decrease in the number of years of marriage in the population may be among them. The debate over whether society can afford to provide universal treatment for psychiatric disorders needs to take these costs into consideration.

Data on the prevalences, comorbidities, and cohort effects of DSM-III-R major depression (MD) and minor depression (mD) are reported for the nationally representative sample of n = 1,769 adolescents and young adults who participated in the National Comorbidity Survey. Lifetime prevalences are 15.3% (MD) and 9.9% (mD), while 30-day prevalences are 5.8% (MD) and 2.1% (mD). Most cases reported recurrent episodes (73.9% of those with MD and 69.2% with mD) and significant role impairment, including attempted suicide among 21.9% of those with MD. The majority of lifetime cases (76.7% of those with MD and 69.3% with mD) reported other comorbid lifetime NCS/ DSM-III-R disorders. Depression was temporally secondary in the majority of these cases. Number of prior disorders was more important than type of disorders in predicting subsequent depression, raising the possibility that secondary depression is a nonspecific severity marker for earlier disorders. A cohort effect for both MD and mD was documented that persisted even for episodes lasting a year or longer. Increasing prevalences of prior comorbid disorders were found to play an important part in explaining the cohort effect for depression.

Objective The authors explored the epidemiologic characteristics and risk factors of anorexia nervosa and examined the relationship between narrowly defined anorexia nervosa and anorexia-like syndromes. Method Structured interviews were administered to a population-based sample of 2,163 female twins. Anorexia nervosa was diagnosed by computer algorithm ("computer narrow") and by narrow and broad clinical definitions. Results Lifetime prevalence estimates of 0.51%, 1.62%, and 3.70% were obtained for the computer narrow, clinical narrow, and clinical broad diagnoses, respectively. Dieting status, greater number of years of parental education, low self-esteem, high levels of neuroticism, and maternal overprotectiveness were significantly associated with anorexia nervosa. Both the pattern of comorbidity and the relationship to epidemiologic risk factors suggested an etiologic continuity between narrowly and broadly defined anorexic syndromes. Co-twins of twins with anorexia nervosa were at significantly higher risk for lifetime anorexia nervosa, bulimia nervosa, major depression, and current low body mass index. Significant comorbidity was found between anorexia nervosa and major depression, bulimia nervosa, generalized anxiety disorder, alcoholism, phobias, and panic disorder. Conclusions The authors' analyses support the hypothesis of a spectrum of anorexic-like syndromes in women. These syndromes are familial and share familial etiologic factors with major depression and bulimia nervosa.

We describe the implementation of multivariate models of familial resemblance with the Mx package. The structural equation models allow for the effects of assortative mating, additive and dominant genes, common and specific environment, and both genetic and cultural transmission between generations. Two approaches are compared: a correlational one based on Fulker and a factor model described by Phillips and Fulker. Both are illustrated by application to published data on social fears and fear of leadership measured in monozygotic and dizygotic twins and their parents. In the example data, genetic dominance yields a more parsimonious explanation of the data than does cultural transmission, although neither is needed to obtain a good fit to the data. A model of reduced genetic correlation between generations also fits the data but has inherent limitations in this sample. Extensions to sex-limitation and more complex models are discussed.

It is shown how information on the direction of causation between variables may be obtained from a cross-sectional study of pairs of relatives. This method is applied to the study of the relationship between ratings of parents' rearing style and depression in their offspring. Adult female twins ascertained from a population-based registry in Virginia completed the Center for Epidemiological Studies - Depression Scale (CESD) and a 7-item short form of the Parental Bonding Instrument (PBI) about each of their parents. Two dimensions of parental behavior, overprotectiveness and coldness, were analyzed jointly with depression data in both genetic factor and directional genetic models. Models that specify ratings of parents as a cause of depression in the offspring fit the data significantly better than models that specify depression as a cause of ratings of parents. A still better fit is obtained with models that specify common genetic variance to depression and ratings, though causal models with error variance perform almost as well. In general, ratings of fathers show more genetic and less shared environmental variance than ratings of mothers, which might arise from more consistent treatment of offspring by mothers than by fathers. No effect of children eliciting parental rearing style was detected with these data. The relative merits of instrumental variable, longitudinal, and family approaches to testing causal models are discussed. © 1994 Wiley-Liss, Inc.

There has been recent interest in the possibility of dividing bulimia nervosa into two subtypes based on the method of weight prevention utilized by the individual. In an attempt to see if such a division is justified, this study compared 54 purging bulimics with 69 nonpurging bulimics ascertained from a population-based register of Virginia female twins. A bulimic was defined as a "purger" if she engaged in vomiting or laxative abuse. These two groups were examined on a variety of demographic, weight, and personality measures after controlling for the presence of obesity. No significant differences were found between the two groups on any of the variables examined.

SynopsisA genetic analysis of the co-occurrence of bulimia and major depression (MD) was performed on 1033 female twin pairs obtained from a population based register. Personal interviews were conducted and clinical diagnoses made according to DSM-III-R criteria.Additive genes, but not family environment, are found to play an important aetiological role in both bulimia and MD. The genetic liabilities of the two disorders are correlated 0·456. While unique environmental factors account for around half of the variation in liability to both bulimia and MD, these risk factors appear to be unrelated, i.e., each disorder has its own set of unique environmental risk factors. Thus, the genetic liability of bulimia and MD is neither highly specific nor entirely nonspecific. There is some genetic correlation between the two disorders as well as some genetic and environmental risk factors unique to each disorder. Limitations and directions for future research are discussed.

Thirty same-sex twin pairs were identified in which both members were assessed at baseline and one twin subsequently developed dementia, at least 3 years subsequent to the baseline measurement, while the partner remained cognitively intact for at least three additional years. Eighteen of the 30 cases were diagnosed with Alzheimer’s disease. Baseline assessments, conducted when twins’ average age was 70.6 (SD = 6.8), included a mailed questionnaire and in-person testing. Which twin would develop dementia was predicted by less favorable lipid values (higher apoB, ratio of apoB to apoA1, and total cholesterol), poorer grip strength, and—to a lesser extent—higher emotionality on the EAS Temperament Scale. Given the long preclinical period that characterizes Alzheimer’s disease, these findings may suggest late life risk factors for dementia, or may reflect changes that are part of preclinical disease.

Irritability is a diagnostic symptom of major depressive disorder (MDD) in children and adolescents but not in adults in both the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) and International Classification of Diseases (ICD-10) systems. We explore the importance of irritability for subtyping adult DSM-IV MDD in the National Comorbidity Survey Replication (NCS-R), a national US adult household survey. The WHO Composite International Diagnostic Interview (CIDI) was used to assess prevalence of many DSM-IV disorders in the lifetime and in the year before interview (12-month prevalence). MDD was assessed conventionally (that is, requiring either persistent sadness or loss of interest), but with irritability included as one of the Criterion A symptoms. We also considered the possibility that irritability might be a diagnostic symptom of adult MDD (that is, detect cases who had neither sad mood nor loss of interest). Twelve-month MDD symptom severity was assessed with the Quick Inventory of Depressive Symptomatology and role impairment with the Sheehan Disability Scale. After excluding bipolar spectrum disorders, irritability during depressive episodes was reported by roughly half of respondents with lifetime DSM-IV MDD. Irritability in the absence of either sad mood or loss of interest, in comparison, was rare. Irritability in MDD was associated with early age of onset, lifetime persistence, comorbidity with anxiety and impulse-control disorders, fatigue and self-reproach during episodes, and disability. Irritability was especially common in MDD among respondents in the age range 18-44 and students. Further investigation is warranted of distinct family aggregation, risk factors and treatment response. Consideration should also be given to including irritability as a nondiagnostic symptom of adult MDD in DSM-V and ICD-11.

Objective: This study described the rate and adequacy of mental health service use among participants in the Mexico National Comorbidity Survey and the correlates of any 12-month treatment and of adequate treatment. Method: The authors conducted face-to-face household surveys of a probability sample of individuals ages 18 to 65 years in the noninstitutionalized population living in urban areas of Mexico from 2001 to 2002. The use of mental health services and 12-month DSM-IV disorders was assessed with the World Mental Health version of the World Health Organization Composite International Diagnostic Interview. The rates and correlates of any service use and the adequacy of treatment were identified in logistic regression analyses, taking into account the complex sample design and weighting process. Results: The data reported here were based on 2,362 interviews. Fewer than one in five respondents with any psychiatric disorder during the last 12 months used any service during the prior year. The rates of service use by those with mood disorders were somewhat higher. About one in every two respondents who used services received minimally adequate care. Conclusions: The authors found large unmet needs for mental health services among those with psychiatric disorders. Those with mental illness and those who deliver or seek to improve mental health care in Mexico face enormous challenges.

CONTEXT: Little is known about the epidemiology of intermittent explosive disorder (IED). OBJECTIVE: To present nationally representative data on the prevalence and correlates of DSM-IV IED. DESIGN: The World Health Organization Composite International Diagnostic Interview was used to assess DSM-IV anxiety disorders, mood disorders, substance use disorders, and impulse control disorders. SETTING: The National Comorbidity Survey Replication, a face-to-face household survey carried out in 2001-2003. PARTICIPANTS: A nationally representative sample of 9282 people 18 years and older. MAIN OUTCOME MEASURE: Diagnoses of DSM-IV IED. RESULTS: Lifetime and 12-month prevalence estimates of DSM-IV IED were 7.3% and 3.9%, with a mean 43 lifetime attacks resulting in 1359 dollars in property damage. Intermittent explosive disorder-related injuries occurred 180 times per 100 lifetime cases. Mean age at onset was 14 years. Sociodemographic correlates were uniformly weak. Intermittent explosive disorder was significantly comorbid with most DSM-IV mood, anxiety, and substance disorders. Although the majority of people with IED (60.3%) obtained professional treatment for emotional or substance problems at some time in their life, only 28.8% ever received treatment for their anger, while only 11.7% of 12-month cases received treatment for their anger in the 12 months before interview. CONCLUSIONS: Intermittent explosive disorder is a much more common condition than previously recognized. The early age at onset, significant associations with comorbid mental disorders that have later ages at onset, and low proportion of cases in treatment all make IED a promising target for early detection, outreach, and treatment. Road rage, temper outbursts that involve throwing or breaking objects, and some types of intimate partner violence can sometimes be associated with IED. Language: en

Despite its inclusion in DSM-IV, little is known about the prevalence or correlates of adult separation anxiety disorder or its relationship to the childhood disorder. Results of the first epidemiological study of adult separation anxiety disorder, to the authors' knowledge, and its relationship to childhood separation anxiety disorder are presented.Data were from the National Comorbidity Survey Replication (NCS-R), a nationally representative survey of U.S. households. A fully structured, lay-administered diagnostic interview assessed a wide range of DSM-IV disorders, including separation anxiety disorder. No independent clinical validation was obtained of the assessment.Lifetime prevalence estimates of childhood and adult separation anxiety disorders were 4.1% and 6.6%, respectively. Approximately one-third of the respondents who were classified as childhood cases (36.1%) had an illness that persisted into adulthood, although the majority classified as adult cases (77.5%) had first onset in adulthood. The assessment of separation anxiety disorder in the NCS-R was comorbid with other NCS-R or DSM-IV disorders and associated with severe role impairment in roughly half of the comorbid cases and one-fourth of the pure cases. The majority of people with estimated adult separation anxiety disorder are untreated, even though many obtain treatment for comorbid conditions.Criteria for adult separation anxiety disorder should be refined in future editions of DSM because the disorder is likely to be much more common in adults than previously recognized. Research is needed to develop and evaluate treatments that take into consideration its high comorbidity with other DSM-IV disorders.

Despite growing interest in adult attention deficit hyperactivity disorder (ADHD), little is known about its prevalence or correlates.A screen for adult ADHD was included in a probability subsample (N=3,199) of 18-44-year-old respondents in the National Comorbidity Survey Replication, a nationally representative household survey that used a lay-administered diagnostic interview to assess a wide range of DSM-IV disorders. Blinded clinical follow-up interviews of adult ADHD were carried out with 154 respondents, oversampling those with positive screen results. Multiple imputation was used to estimate prevalence and correlates of clinician-assessed adult ADHD.The estimated prevalence of current adult ADHD was 4.4%. Significant correlates included being male, previously married, unemployed, and non-Hispanic white. Adult ADHD was highly comorbid with many other DSM-IV disorders assessed in the survey and was associated with substantial role impairment. The majority of cases were untreated, although many individuals had obtained treatment for other comorbid mental and substance-related disorders.Efforts are needed to increase the detection and treatment of adult ADHD. Research is needed to determine whether effective treatment would reduce the onset, persistence, and severity of disorders that co-occur with adult ADHD.

Background Little is known about the general population prevalence or severity of DSM-IV mental disorders. Objective To estimate 12-month prevalence, severity, and comorbidity of DSM-IV anxiety, mood, impulse control, and substance disorders in the recently completed US National Comorbidity Survey Replication. Design and Setting Nationally representative face-to-face household survey conducted between February 2001 and April 2003 using a fully structured diagnostic interview, the World Health Organization World Mental Health Survey Initiative version of the Composite International Diagnostic Interview. Participants Nine thousand two hundred eighty-two English-speaking respondents 18 years and older. Main Outcome Measures Twelve-month DSM-IV disorders. Results Twelve-month prevalence estimates were anxiety, 18.1%; mood, 9.5%; impulse control, 8.9%; substance, 3.8%; and any disorder, 26.2%. Of 12-month cases, 22.3% were classified as serious; 37.3%, moderate; and 40.4%, mild. Fifty-five percent carried only a single diagnosis; 22%, 2 diagnoses; and 23%, 3 or more diagnoses. Latent class analysis detected 7 multivariate disorder classes, including 3 highly comorbid classes representing 7% of the population. Conclusion Although mental disorders are widespread, serious cases are concentrated among a relatively small proportion of cases with high comorbidity.

Background. A self-report screening scale of adult attention-deficit/hyperactivity disorder (ADHD), the World Health Organization (WHO) Adult ADHD Self-Report Scale (ASRS) was developed in conjunction with revision of the WHO Composite International Diagnostic Interview (CIDI). The current report presents data on concordance of the ASRS and of a short-form ASRS screener with blind clinical diagnoses in a community sample.Method. The ASRS includes 18 questions about frequency of recent DSM-IV Criterion A symptoms of adult ADHD. The ASRS screener consists of six out of these 18 questions that were selected based on stepwise logistic regression to optimize concordance with the clinical classification. ASRS responses were compared to blind clinical ratings of DSM-IV adult ADHD in a sample of 154 respondents who previously participated in the US National Comorbidity Survey Replication (NCS-R), oversampling those who reported childhood ADHD and adult persistence.Results. Each ASRS symptom measure was significantly related to the comparable clinical symptom rating, but varied substantially in concordance (Cohen's κ in the range 0·16–0·81). Optimal scoring to predict clinical syndrome classifications was to sum unweighted dichotomous responses across all 18 ASRS questions. However, because of the wide variation in symptom-level concordance, the unweighted six-question ASRS screener outperformed the unweighted 18-question ASRS in sensitivity (68·7% v. 56·3%), specificity (99·5% v. 98·3%), total classification accuracy (97·9% v. 96·2%), and κ (0·76 v. 0·58).Conclusions. Clinical calibration in larger samples might show that a weighted version of the 18-question ASRS outperforms the six-question ASRS screener. Until that time, however, the unweighted screener should be preferred to the full ASRS, both in community surveys and in clinical outreach and case-finding initiatives.

Background To estimate the prevalence and correlates of clinician-diagnosed DSM-IV nonaffective psychosis (NAP) in a national household survey. Methods Data came from the United States National Comorbidity Survey Replication (NCS-R). A screen for NAP was followed by blinded sub-sample clinical reappraisal interviews. Logistic regression was used to impute clinical diagnoses to respondents who were not re-interviewed. The method of Multiple Imputation (MI) was used to estimate prevalence and correlates. Results Clinician-diagnosed NAP was well predicted by the screen (area under the curve [AUC] = .80). The MI prevalence estimate of NAP (standard error in parentheses) is 5.0 (2.6) per 1000 population lifetime and 3.0 (2.2) per 1000 past 12 months. The vast majority (79.4%) of lifetime and 12-month (63.7%) cases met criteria for other DSM-IV hierarchy-free disorders. Fifty-eight percent of 12-month cases were in treatment, most in the mental health specialty sector. Conclusions The screen for NAP in the NCS-R greatly improved on previous epidemiological surveys in reducing false positives, but coding of open-ended screening scale responses was still needed to achieve accurate prediction. The lower prevalence estimate than in total-population incidence studies raises concerns that systematic nonresponse bias causes downward bias in survey prevalence estimates of NAP.

Background: High prevalence estimates in epidemiological surveys have led to concerns that the DSM system is overly inclusive and that mild cases should be excluded from future DSM editions. Objective: To demonstrate that the DSM-III-R disorders in the baseline National Comorbidity Survey (NCS) can be placed on a severity gradient that has a dose-response relationship with outcomes assessed a decade later in the NCS follow-up survey (NCS-2) and that no inflection point exists at the mild severity level. Methods: The NCS was a nationally representative household survey of DSM-III-R disorders in the 3-year time span 1990-1992. The NCS-2 is a follow-up survey of 4375 NCS respondents (76.6% conditional response rate) reinterviewed in 2000 through 2002. The NCS-2 outcomes include hospitalization for mental health or substance disorders, work disability due to these disorders, suicide attempts, and serious mental illness. Results:Twelve-month NCS/DSM-III-Rdisorders were disaggregatedinto3.2%severe,3.2%serious,8.7%moderate, and 16.0% mild case categories. All 4 case categorieswereassociatedwithstatisticallysignificantly(P.05, 2-sided tests) elevated risk of the NCS-2 outcomes comparedwithbaselinenoncases,withoddsratiosofanyoutcome ranging monotonically from 2.4 (95% confidence interval, 1.6-3.4) to 15.1 (95% confidence interval, 10.022.9)formildtoseverecases.Oddsratioscomparingmild to moderate cases were generally nonsignificant. Conclusions: There is a graded relationship between mental illness severity and later clinical outcomes. Retention of mild cases in the DSM is important to represent the fact that mental disorders (like physical disorders)varyinseverity.Decisionsabouttreatingmildcases should be based on cost-effectiveness not current severity. Cost-effectiveness analysis should include recognition that treatment of mild cases might prevent a substantial proportion of future serious cases. Arch Gen Psychiatry. 2003;60:1117-1122

ContextUncertainties exist about prevalence and correlates of major depressive disorder (MDD).ObjectiveTo present nationally representative data on prevalence and correlates of MDD by Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria, and on study patterns and correlates of treatment and treatment adequacy from the recently completed National Comorbidity Survey Replication (NCS-R).DesignFace-to-face household survey conducted from February 2001 to December 2002.SettingThe 48 contiguous United States.ParticipantsHousehold residents ages 18 years or older (N = 9090) who responded to the NCS-R survey.Main Outcome MeasuresPrevalence and correlates of MDD using the World Health Organization's (WHO) Composite International Diagnostic Interview (CIDI), 12-month severity with the Quick Inventory of Depressive Symptomatology Self-Report (QIDS-SR), the Sheehan Disability Scale (SDS), and the WHO disability assessment scale (WHO-DAS). Clinical reinterviews used the Structured Clinical Interview for DSM-IV.ResultsThe prevalence of CIDI MDD for lifetime was 16.2% (95% confidence interval [CI], 15.1-17.3) (32.6-35.1 million US adults) and for 12-month was 6.6% (95% CI, 5.9-7.3) (13.1-14.2 million US adults). Virtually all CIDI 12-month cases were independently classified as clinically significant using the QIDS-SR, with 10.4% mild, 38.6% moderate, 38.0% severe, and 12.9% very severe. Mean episode duration was 16 weeks (95% CI, 15.1-17.3). Role impairment as measured by SDS was substantial as indicated by 59.3% of 12-month cases with severe or very severe role impairment. Most lifetime (72.1%) and 12-month (78.5%) cases had comorbid CIDI/DSM-IV disorders, with MDD only rarely primary. Although 51.6% (95% CI, 46.1-57.2) of 12-month cases received health care treatment for MDD, treatment was adequate in only 41.9% (95% CI, 35.9-47.9) of these cases, resulting in 21.7% (95% CI, 18.1-25.2) of 12-month MDD being adequately treated. Sociodemographic correlates of treatment were far less numerous than those of prevalence.ConclusionsMajor depressive disorder is a common disorder, widely distributed in the population, and usually associated with substantial symptom severity and role impairment. While the recent increase in treatment is encouraging, inadequate treatment is a serious concern. Emphasis on screening and expansion of treatment needs to be accompanied by a parallel emphasis on treatment quality improvement.

Item does not contain fulltext We analyzed survey data from Canada, Chile, Germany, the Netherlands, and the United States to study the prevalence and treatment of mental and substance abuse disorders. Total past-year prevalence estimates range between 17.0 percent (Chile) and 29.1 percent (U.S.). Many cases are mild. Although disorder severity is strongly related to treatment, one- to two-thirds of serious cases receive no treatment each year. Most treatment goes to minor and mild cases. Undertreatment of serious cases is most pronounced among young, poorly educated males. Outreach is needed to reduce barriers to care among serious cases and young people at risk of serious disorders.

Objective. Expanded health risk appraisal (HRA) surveys can help employers target chronic conditions for outreach or disease management interventions by providing data on the prevalences of conditions and their effects on work performance. However, concerns exist about the accuracy of this data because most HRAs have low response rates. We evaluated these concerns by examining the prevalences and work impairments associated with chronic conditions across four HRA subsamples that differed in intensity of recruitment effort. Methods. Two thousand five hundred thirty-nine working people were invited to complete an expanded HRA survey that included questions about chronic conditions, work impairments, and demographics. Condition prevalences and associations between conditions and work impairment were compared across subsamples who responded after a single mailing, after two mailings, and in a telephone interview after the mailings either with or without a $20 incentive. Results. Consistent with previous research, response rates varied dramatically across the four subsamples (from 20.1% with only one mailing to 67.7% with telephone administration and a financial incentive). However, the estimated prevalences of chronic conditions, levels of work impairment, and effects of chronic conditions on work impairment did not differ with intensity of recruitment effort. Conclusions. Expanded HRAs can provide useful data on the prevalences and work impairments associated with chronic conditions even if response rates are low. Confirmation of these results is required, however, in new samples. Additional research is also needed on innovative and cost-effective strategies to improve HRA response rates.

Background Variations in the relationships among income, use of mental health services, and sector of care are examined by comparing data from 3 countries that differ in the organization and financing of mental health services. Methods Data come from the 1990-1992 National Comorbidity Survey (n=5384), the 1990-1991 Mental Health Supplement to the Ontario Health Survey (n=6321), and the 1996 Netherlands Mental Health Survey and Incidence Study (n=6031). Analysis of the association between income and use of mental health services was carried out for the population that was between ages 18 and 54 years. Differential use of mental health treatment was examined in 3 sectors: the general medical sector, the specialty sector, and the human services sector. Results No significant association between income and probability of any mental health treatment was observed for persons with psychiatric disorders in any of the 3 countries. However, there were significant differences among countries in the association between income and sector of mental health care treatment. In the United States, income is positively related to treatment being received in the specialty sector and negatively related to treatment being received in the human services sector. In the Netherlands, patients in the middle-income bracket are less likely to receive specialty care, while those in the high-income bracket are less likely to be seen in the human service sector. Income is unrelated to the sector of care for patients in Ontario. Conclusions Future research should examine whether differential access to the specialty sector for low-income people in the United States is associated with worse mental health outcomes.

The subject of this study was the relation between retrospectively reported early-onset psychiatric disorders and subsequent teenage parenthood in the general population.The data were from 5,877 respondents aged 15-54 years in the National Comorbidity Survey, a nationally representative household survey. Information on respondents' DSM-III-R anxiety disorders, mood disorders, substance abuse disorders, and conduct disorder, age at the birth of the first child, and teenage sexual activity was collected in face-to-face interviews.Early-onset psychiatric disorders were associated with subsequent teenage parenthood among both females and males, with significant odds ratios of 2.0-12.0 and population attributable risk proportions of 6.2%-33.7%. Disaggregation analyses showed that disorders were associated with increased probability of sexual activity but not with decreased probability of using contraception.These results add to a growing body of evidence that psychiatric disorders are associated with a variety of adverse life consequences. The current policy debate concerning universal insurance coverage needs to take this into consideration. Planners of interventions aimed at preventing teenage pregnancy should consider including a mental health treatment component in their intervention packages. Mental health professionals treating adolescents need to be sensitized to their higher risk of pregnancy, while family doctors and specialists treating teenage mothers or their children need to be sensitized to the mothers' higher risk of psychiatric disorder.Data from the US National Comorbidity Survey on 5877 respondents 15-54 years of age were used to assess the relationship between retrospectively identified early-onset psychiatric disorders and subsequent adolescent parenthood. Between 21-24% of the sample's male and female age cohorts reported having their first child at ages 15-19 years. The cumulative and conditional probability curves for adolescent parenthood were consistently higher among men and women with prior psychiatric diagnoses of anxiety, affective, addictive, and conduct disorders than among those without psychiatric diagnoses. The diagnosis most predictive of adolescent parenthood was addictive disorders. The population attributable risk proportions of births of first children to teenagers associated with the psychiatric disorders were 11.1% in the teenage female subsample with premarital childbearing, 6.2% in the teenage female subsample with marital childbearing, and 33.7% in the teenage male subsample with premarital parenthood. Physicians and mental health professionals who work with adolescents with psychiatric conditions should be aware of the increased risk of adolescent pregnancy and a mental health component should be added to adolescent pregnancy prevention programs.

Background: Depression, a clinically heterogeneous syndrome, may also be etiologically heterogeneous. Using a prospective, epidemiologic, and genetically informative sample of adult female twins, we identify and validate a typology of depressive syndromes. Methods: Latent class analysis was applied to 14 disaggregated DSM-III-R symptoms for major depression reported over the last year by members of 1029 female-female twin pairs. Results: Seven classes were identified, of which 3 represented clinically significant depressive syndromes: (1) mild typical depression , (2) atypical depression , and (3) severe typical depression . Severe typical depression was characterized by comorbid anxiety and panic, long episodes, impairment, and help seeking. Atypical depression was similar in severity to mild typical depression, but was characterized by increased eating, hypersomnia, frequent, relatively short episodes, and a proclivity to obesity. Individuals with recurrent episodes tended to have the same syndrome on each occasion. The members of twin pairs concordant for depression had the same depressive syndrome more often than expected by chance and this resemblance was greater in monozygotic than in dizygotic pairs. Conclusion: In an epidemiologic sample of female twins, depression is not etiologically homogeneous, but is instead made up of several syndromes that are at least partially distinct from a clinical, longitudinal, and familial/genetic perspective.

Self-report symptoms of anxiety are widely used in mental health and social science research as an index of current psychiatric state. Previous twin studies have suggested that genetic factors account for a significant proportion of the variance in these symptoms. To replicate and extend these findings, we examined self-report symptoms of panic-phobia and somatization in the "Virginia 30,000" twin-family sample. Model fitting applied to 80 unique relationships in the twin-family pedigree produced the following major results: (i) genetic effects were significant for both symptom factors, accounting for between 25 and 49% of the total variance, with the exception of symptoms of panic-phobia in females, where they accounted for 15-16% of the variance; (ii) familial environmental effects were absent for symptoms of somatization, while for symptoms of panic-phobia they accounted for a very small proportion of variance in males (< or = 1.2%) and a modest proportion in females (6-17%); (iii) spousal correlations were present for both factors, ranging from +0.05 to +0.20; (iv) genetic factors which influenced symptoms were generally the same in males and females, although their effect was greater in males; (v) heritability estimates were lower in the population-based than in the volunteer sample; and (vi) when test-retest reliability was included in the model, results suggest that genetic factors account for at least half of the stable variance for all symptom factors, except panic-phobia in females. Our results support the validity of previous twin studies of self-report symptoms of anxiety and suggest that genetic factors significantly influence these symptoms but familial-environmental factors play little or no etiologic role.

Background: Although prior family and twin studies have examined the relationship between the genetic and environmental risk factors for pairs of psychiatric disorders, the interrelationship between these classes of risk factors for a broad range of psychiatric disorders remains largely unknown. Methods: An epidemiologic sample of 1030 femalefemale twin pairs with known zygosity, ascertained from the Virginia Twin Registry, were evaluated by a personal interview conducted by mental health professionals, assessing lifetime history of phobia, generalized anxiety disorder, panic disorder, bulimia nervosa, major depression, and alcoholism. Results: A multivariate twin analysis suggested the following: First, genetic, familial-environmental, and individual-specific environmental risk factors each cause a unique pattern of comorbidity among the six disorders. Second, genetic influences on these disorders are best explained by two factors, the first of which loads heavily on phobia, panic disorder, and bulimia nervosa and the second, on major depression and generalized anxiety disorder. Third, unlike other disorders, genetic influences on alcoholism are largely disorder specific. Fourth, familialenvironmental influences on these disorders are best explained by a single factor that substantially influenced liability to bulimia nervosa only. Fifth, individual-specific environmental influences on the risk for these psychiatric disorders are best explained by a single factor, with highest loadings on generalized anxiety disorder and major depression and with large-disorder—specific loadings, especially on phobias, panic disorder, and alcoholism. Conclusions: These results support the following hypotheses: First, each major risk factor domain (genes, family environment, and individual-specific environment) influences comorbidity between these disorders in a distinct manner. Second, genetic influences on these six disorders are neither highly specific nor highly nonspecific. Neither a model that contains a discrete set of genetic factors for each disorder nor a model in which all six disorders results from a single set of genes is well supported. Third, the anxiety disorders are not, from a genetic perspective, etiologically homogeneous. Fourth, most of the genetic factors that influence vulnerability to alcoholism in women do not alter the risk for development of other common psychiatric disorders. These results should be interpreted in the context of both the strengths and limitations of multivariate twin analysis.

Objective: Self-reported symptoms of depression are commonly used in mental health re­ search to assess current psychiatric state, yet wide variation in these symptoms among indi­ viduals has been found in both clinical and epidemiologic populations. The authors sought to understand, from a genetic-epidemiologic perspective, the sources of individual differences in depressive symptoms. Method: Self-reported symptoms of depression were assessed in two samples of twins and their spouses, parents, siblings, and offspring: one sample contained volunteer twins recruited through the American Association of Retired Persons and their rela­ tives (N=19,203 individuals) and the other contained twins from a population-based twin registry in Virginia and their relatives (N=11,242 individuals). Model fitting by an iterative, diagonal, weighted least squares method was applied to the 80 different family relationships in the extended twin-family design. Results: Independent analyses of the two samples revealed that the level of depressive symptoms was modestly familial, and familial resemblance could be explained solely by genetic factors and spousal resemblance. The estimated heritability of depressive symptoms was between 30% and 37%. There was no evidence that the liability to depressive symptoms was environmentally transmitted from parents to offspring or was in­ fluenced by environmental factors shared either generally among siblings or specifically be­ tween twins. With correction for unreliability of measurement, genetic factors accounted for half of the stable variance in depressive symptoms. Conclusions: Depressive symptoms in adulthood partly reflect enduring characteristics of temperament that are substantially influ­ enced by hereditary factors but little, or not at all, by shared environmental experiences in the family of origin. (Am] Psychiatry 1994; 151:1605-1614)

We extend the DeFries-Fulker regression model for the analysis of quantitative twin data to cover binary traits and genetic dominance. In the proposed logistic regression model, the cotwin's trait status, C, is the response variable, while the proband's trait status, P, is a predictor variable coded as k (affected) and 0 (unaffected). Additive genetic effects are modeled by the predictor variable PR, which equals P for monozygotic (MZ) and P/2 for dizygotic (DZ) twins; and dominant genetic effects, by PD, which equals P for MZ and P/4 for DZ twins. By setting an appropriate scale for P (i.e., the value of k), the regression coefficients of P, PR, and PD are estimates of the proportion of variance in liability due to common family environment, additive genetic effects, and dominant genetic effects, respectively, for a multifactorial liability-threshold model. This model was applied to data on lifetime depression from the Virginia Twin Registry and produced results similar to those from structural equation modeling.

Context Only limited information exists about the epidemiology of DSM-IV panic attacks (PAs) and panic disorder (PD). Objective To present nationally representative data about the epidemiology of PAs and PD with or without agoraphobia (AG) on the basis of the US National Comorbidity Survey Replication findings. Design and Setting Nationally representative face-to-face household survey conducted using the fully structured World Health Organization Composite International Diagnostic Interview. Participants English-speaking respondents (N=9282) 18 years or older. Main Outcome Measures Respondents who met DSM-IV lifetime criteria for PAs and PD with and without AG. Results Lifetime prevalence estimates are 22.7% for isolated panic without AG (PA only), 0.8% for PA with AG without PD (PA-AG), 3.7% for PD without AG (PD only), and 1.1% for PD with AG (PD-AG). Persistence, lifetime number of attacks, and number of years with attacks increase monotonically across these 4 subgroups. All 4 subgroups are significantly comorbid with other lifetime DSM-IV disorders, with the highest odds for PD-AG and the lowest for PA only. Scores on the Panic Disorder Severity Scale are also highest for PD-AG (86.3% moderate or severe) and lowest for PA only (6.7% moderate or severe). Agoraphobia is associated with substantial severity, impairment, and comorbidity. Lifetime treatment is high (from 96.1% for PD-AG to 61.1% for PA only), but 12-month treatment meeting published treatment guidelines is low (from 54.9% for PD-AG to 18.2% for PA only). Conclusion Although the major societal burden of panic is caused by PD and PA-AG, isolated PAs also have high prevalence and meaningful role impairment.

Context Little is known about lifetime prevalence or age of onset of DSM-IV disorders. Objective To estimate lifetime prevalence and age-of-onset distributions of DSM-IV disorders in the recently completed National Comorbidity Survey Replication. Design and Setting Nationally representative face-to-face household survey conducted between February 2001 and April 2003 using the fully structured World Health Organization World Mental Health Survey version of the Composite International Diagnostic Interview. Participants Nine thousand two hundred eighty-two English-speaking respondents aged 18 years and older. Main Outcome Measures Lifetime DSM-IV anxiety, mood, impulse-control, and substance use disorders. Results Lifetime prevalence estimates are as follows: anxiety disorders, 28.8%; mood disorders, 20.8%; impulse-control disorders, 24.8%; substance use disorders, 14.6%; any disorder, 46.4%. Median age of onset is much earlier for anxiety (11 years) and impulse-control (11 years) disorders than for substance use (20 years) and mood (30 years) disorders. Half of all lifetime cases start by age 14 years and three fourths by age 24 years. Later onsets are mostly of comorbid conditions, with estimated lifetime risk of any disorder at age 75 years (50.8%) only slightly higher than observed lifetime prevalence (46.4%). Lifetime prevalence estimates are higher in recent cohorts than in earlier cohorts and have fairly stable intercohort differences across the life course that vary in substantively plausible ways among sociodemographic subgroups. Conclusions About half of Americans will meet the criteria for a DSM-IV disorder sometime in their life, with first onset usually in childhood or adolescence. Interventions aimed at prevention or early treatment need to focus on youth.

Background Public Law 102-321 established a block grant for adults with "serious mental illness" (SMI) and required the Substance Abuse and Mental Health Services Administration (SAMHSA) to develop a method to estimate the prevalence of SMI. Methods Three SMI screening scales were developed for possible use in the SAMHSA National Household Survey on Drug Abuse: the Composite International Diagnostic Interview Short-Form (CIDI-SF) scale, the K10/K6 nonspecific distress scales, and the World Health Organization Disability Assessment Schedule (WHO-DAS). An enriched convenience sample of 155 respondents was administered all screening scales followed by the 12-month Structured Clinical Interview for DSM-IV and the Global Assessment of Functioning (GAF). We defined SMI as any 12-month DSM-IV disorder, other than a substance use disorder, with a GAF score of less than 60. Results All screening scales were significantly related to SMI. However, neither the CIDI-SF nor the WHO-DAS improved prediction significantly over the K10 or K6 scales. The area under the receiver operating characteristic curve of SMI was 0.854 for K10 and 0.865 for K6. The most efficient screening scale, K6, had a sensitivity (SE) of 0.36 (0.08) and a specificity of 0.96 (0.02) in predicting SMI. Conclusions The brevity and accuracy of the K6 and K10 scales make them attractive screens for SMI. Routine inclusion of either scale in clinical studies would create an important, and heretofore missing, crosswalk between community and clinical epidemiology.

Background Although recent research has shown that many people in the United States use complementary and alternative medical (CAM) therapies, little is known about time trends in use. Objective To present data on time trends in CAM therapy use in the United States over the past half-century. Design Nationally representative telephone survey of 2055 respondents that obtained information on current use, lifetime use, and age at first use for 20 CAM therapies. Setting The 48 contiguous U.S. states. Participants Household residents 18 years of age and older. Measurement Retrospective self-reports of age at first use for each of 20 CAM therapies. Results Previously reported analyses of these data showed that more than one third of the U.S. population was currently using CAM therapy in the year of the interview (1997). Subsequent analyses of lifetime use and age at onset showed that 67.6% of respondents had used at least one CAM therapy in their lifetime. Lifetime use steadily increased with age across three age cohorts: Approximately 3 of every 10 respondents in the pre-baby boom cohort, 5 of 10 in the baby boom cohort, and 7 of 10 in the post-baby boom cohort reported using some type of CAM therapy by age 33 years. Of respondents who ever used a CAM therapy, nearly half continued to use many years later. A wide range of individual CAM therapies increased in use over time, and the growth was similar across all major sociodemographic sectors of the study sample. Conclusions Use of CAM therapies by a large proportion of the study sample is the result of a secular trend that began at least a half century ago. This trend suggests a continuing demand for CAM therapies that will affect health care delivery for the foreseeable future.

Background General population survey data are presented on the lifetime prevalence of suicide attempts as well as transition probabilities to onset of ideation, plans among ideators, and attempts among ideators either with or without a plan. Risk factors for these transitions are also studied. Methods Data are from part II of the National Comorbidity Survey, a nationally representative survey carried out from 1990 to 1992 in a sample of 5877 respondents aged 15 to 54 years to study prevalences and correlates of DSM-III-R disorders. Transitions are estimated using life-table analysis. Risk factors are examined using survival analysis. Results Of the respondents, 13.5% reported lifetime ideation, 3.9% a plan, and 4.6% an attempt. Cumulative probabilities were 34% for the transition from ideation to a plan, 72% from a plan to an attempt, and 26% from ideation to an unplanned attempt. About 90% of unplanned and 60% of planned first attempts occurred within 1 year of the onset of ideation. All significant risk factors (female, previously married, age less than 25 years, in a recent cohort, poorly educated, and having 1 or more of the DSM-III-R disorders assessed in the survey) were more strongly related to ideation than to progression from ideation to a plan or an attempt. Conclusions Prevention efforts should focus on planned attempts because of the rapid onset and unpredictability of unplanned attempts. More research is needed on the determinants of unplanned attempts.

Context.—Obesity is a well-established risk factor for coronary heart disease (CHD), but whether regional fat distribution contributes independently to risk remains unclear.Objective.—To compare waist-hip ratio (WHR) and waist circumference in determining risk of CHD in women.Design and Setting.—Prospective cohort study among US female registered nurses participating in the Nurses' Health Study conducted between 1986, when the nurses completed a questionnaire, and follow-up in June 1994.Participants.—A total of 44,702 women aged 40 to 65 years who provided waist and hip circumferences and were free of prior CHD, stroke, or cancer in 1986.Main Outcome Measures.—Incidence of CHD (nonfatal myocardial infarction or CHD death).Results.—During 8 years of follow-up 320 CHD events (251 myocardial infarctions and 69 CHD deaths) were documented. Higher WHR and greater waist circumference were independently associated with a significantly increased age-adjusted risk of CHD. After adjusting for body mass index (BMI) (defined as weight in kilograms divided by the square of height in meters) and other cardiac risk factors, women with a WHR of 0.88 or higher had a relative risk (RR) of 3.25 (95% confidence interval [CI], 1.78-5.95) for CHD compared with women with a WHR of less than 0.72. A waist circumference of 96.5 cm (38 in) or more was associated with an RR of 3.06 (95% CI, 1.54-6.10). The WHR and waist circumference were independently strongly associated with increased risk of CHD also among women with a BMI of 25 kg/m2 or less. After adjustment for reported hypertension, diabetes, and high cholesterol level, a WHR of 0.76 or higher or waist circumference of 76.2 cm (30 in) or more was associated with more than a 2-fold higher risk of CHD.Conclusions.—The WHR and waist circumference are independently associated with risk of CHD in women.