Research on the structure of comorbidity among common mental disorders has largely focused on current prevalence rather than on the development of comorbidity. This report presents preliminary results of the latter type of analysis based on the National Comorbidity Survey Replication Adolescent Supplement (NCS-A).
A national survey was carried out of adolescent mental disorders. DSM-IV diagnoses were based on the Composite International Diagnostic Interview administered to adolescents and questionnaires self-administered to parents. Factor analysis examined comorbidity among 15 lifetime DSM-IV disorders. Discrete-time survival analysis was used to predict first onset of each disorder from information about prior history of the other 14 disorders.
Factor analysis found four factors representing fear, distress, behavior, and substance disorders. Associations of temporally primary disorders with the subsequent onset of other disorders (dated using retrospective age-of-onset reports) were almost entirely positive. Within-class associations (e.g., distress disorders predicting subsequent onset of other distress disorders) were more consistently significant (63.2%) than between-class associations (33.0%). Strength of associations decreased as comorbidity among disorders increased. The percent of lifetime disorders explained (in a predictive rather than causal sense) by temporally prior disorders was in the range 3.7-6.9% for earliest-onset disorders (specific phobia and attention-deficit/hyperactivity disorder) and much higher (23.1-64.3%) for later-onset disorders. Fear disorders were the strongest predictors of most other subsequent disorders.
Adolescent mental disorders are highly comorbid. The strong associations of temporally primary fear disorders with many other later-onset disorders suggest that fear disorders might be promising targets for early interventions.
NCS-A; adolescence; epidemiology; lifetime prevalence; lifetime comorbidity; mental disorders
Interventions to treat mental disorders after natural disasters are important both for humanitarian reasons and also for successful post-disaster physical reconstruction that depends on the psychological functioning of the affected population. A major difficulty in developing such interventions, however, is that large between-disaster variation exists in the prevalence of post-disaster mental disorders, making it difficult to estimate need for services in designing interventions without carrying out a post-disaster mental health needs assessment survey. One of the daunting methodological challenges in implementing such surveys is that secondary stressors unique to the disaster often need to be discovered to understand the magnitude, type, and population segments most affected by post-disaster mental disorders.
This problem is examined in the current commentary by analyzing data from the WHO World Mental Health (WMH) Surveys. We analyze the extent to which people exposed to natural disasters throughout the world also experienced secondary stressors and the extent to which the mental disorders associated with disasters were more proximally due to these secondary stressors than to the disasters themselves.
Lifetime exposure to natural disasters was found to be high across countries (4.4–7.5%). 10.7–11.4% of those exposed to natural disasters reported the occurrence of other related stressors (e.g. death of a loved one and destruction of property). A monotonic relationship was found between the number of additional stressors and the subsequent onset of mental disorders
These results document the importance of secondary stressors in accounting for the effects of natural disasters on mental disorders. Implications for intervention planning are discussed.
Natural disasters; needs assessment; post-disaster intervention planning
The prevalence of family childhood adversities (FCAs) and their joint effects on the first onset of subsequent mental disorders throughout the life course are rarely examined, especially in Asian communities.
Face-to-face household interviews of 5201 people aged 18–70 years in Beijing and Shanghai were conducted by a multi-stage household probability sampling method. The first onsets of four broad groups of mental disorders and six categories of FCAs were assessed using The World Mental Health Composite International Diagnostic Interview (WMH-CIDI). Joint effects of FCAs were analyzed by the best fitting of several competitive multivariate models.
FCAs were highly prevalent and inter-correlated. Half of them were in a family-dysfunction cluster. The best-fitting model included each of six types of FCA (with family-dysfunction FCAs being the strongest predictors), number of family-dysfunction FCAs, and number of other FCAs. Family-dysfunction FCAs had a significant subadditive association with subsequent disorders. Little specificity was found for the effects of particular FCAs with particular disorders. Predictive effects of FCAs reached the highest in ages 13–24 compared to ages 4–12 and ⩾25. Estimates of population-attributable risk proportions indicated that all FCAs together explained 38.5% of all first-onset disorders.
Chinese children were exposed to a broad spectrum of inter-related FCAs, as found in Western countries. FCAs related to family dysfunction were especially associated with subsequent mental disorders. Biological and/or environmental factors that mediate these long-term effects should be studied in prospective research on broad groups of FCAs.
Childhood adversity (CA); China; family; first onset; mental disorders
Despite significant advances in the study of obsessive-compulsive disorder (OCD), important questions remain about the disorder's public health significance, appropriate diagnostic classification, and clinical heterogeneity. These issues were explored using data from the National Comorbidity Survey Replication (NCS-R), a nationally representative survey of U.S. adults. A subsample of 2073 respondents was assessed for lifetime DSM-IV OCD. More than one-quarter of respondents reported experiencing obsessions or compulsions at some time in their lives. While conditional probability of OCD was strongly associated with the number of obsessions and compulsions reported, only small proportions of respondents met full DSM-IV criteria for lifetime (2.3%) or 12-month (1.2%) OCD. OCD is associated with substantial comorbidity, not only with anxiety and mood disorders but also with impulse-control and substance use disorders. Severity of OCD, assessed by an adapted version of the Yale-Brown Obsessive Compulsive Scale (Y-BOCS), is associated with poor insight, high comorbidity, high role impairment, and high probability of seeking treatment. The high prevalence of subthreshold OCD symptoms may help explain past inconsistencies in prevalence estimates across surveys and suggests that the public health burden of OCD may be greater than its low prevalence implies. Evidence of a preponderance of early-onset cases in males, high comorbidity with a wide range of disorders, and reliable associations between disorder severity and key outcomes may have implications for how OCD is classified in DSM-V.
epidemiology; obsessive behavior; compulsive behavior; obsessive-compulsive behavior; National Comorbidity Survey-Replication
Previous surveys on depression in China focused on prevalence estimates without providing a detailed epidemiological profile.
Face-to-face household interviews were conducted with a multi-stage household probability sample of 2633 adults (age ≥18 years) in Beijing and 2568 in Shanghai between November 2001 and February 2002. The World Health Organization Composite International Diagnostic Interview (CIDI) was used to assess major depressive episode (MDE) according to Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV criteria.
The lifetime prevalence and 1-year prevalence estimates of DSM-IV/CIDI MDE were 3.6 % [95 % confidence interval (CI) 2.8-4.4 %] and 1.8 % (95 % CI 1.2-2.4 %) respectively. No significant gender difference was found in these estimates. Respondents born in 1967 or later were at elevated lifetime risk compared with respondents born in earlier cohorts. The mean age of onset was 30.3 years. Among those reporting 1-year MDE, 15.7, 51.8, 25.3 and 6.4 % reported mild, moderate, severe and very severe symptoms respectively; 4.8, 2.6 and 3.2 % reported suicidal ideation, plans, and recent attempts in the same year respectively. Respondents with 1-year MDE reported a mean of 27.5 days out of role owing to their depression in the year before interview. Significant co-morbidity was found between MDE and other mental disorders [odds ratio (OR) 22.0] and chronic physical disorders (OR 3.2). Only 22.7 % of respondents with 1-year MDE sought treatment.
The low prevalence and insignificant gender difference, but not patterns of onset, course, co-morbidity, and impairment, distinguish the epidemiological profile of MDE in metropolitan China from those in other countries.
Co-morbidity; epidemiology; major depression; metropolitan China; suicide; treatment
The ‘gateway’ pattern of drug initiation describes a normative sequence, beginning with alcohol and tobacco use, followed by cannabis, then other illicit drugs. Previous work has suggested that ‘violations’ of this sequence may be predictors of later problems but other determinants were not considered. We have examined the role of pre-existing mental disorders and sociodemographics in explaining the predictive effects of violations using data from the US National Comorbidity Survey Replication (NCS-R).
The NCS-R is a nationally representative face-to-face household survey of 9282 English-speaking respondents aged 18 years and older that used the World Health Organization (WHO) Composite International Diagnostic Interview (CIDI) to assess DSM-IV mental and substance disorders. Drug initiation was estimated using retrospective age-of-onset reports and ‘violations’ defined as inconsistent with the normative initiation order. Predictors of violations were examined using multivariable logistic regressions. Discrete-time survival analysis was used to see whether violations predicted progression to dependence.
Gateway violations were largely unrelated to later dependence risk, with the exception of small increases in risk of alcohol and other illicit drug dependence for those who initiated use of other illicit drugs before cannabis. Early-onset internalizing disorders were predictors of gateway violations, and both internalizing and externalizing disorders increased the risks of dependence among users of all drugs.
Drug use initiation follows a strong normative pattern, deviations from which are not strongly predictive of later problems. By contrast, adolescents who have already developed mental health problems are at risk for deviations from the normative sequence of drug initiation and for the development of dependence.
Alcohol; cannabis; dependence; gateway; illicit drugs; National Comorbidity Survey Replication; tobacco
The relationship between mental and physical disorders is well established, but there is less consensus as to the nature of their joint association with disability, in part because additive and interactive models of co-morbidity have not always been clearly differentiated in prior research.
Eighteen general population surveys were carried out among adults as part of the World Mental Health (WMH) Survey Initiative (n=42 697). DSM-IV disorders were assessed using face-to-face interviews with the Composite International Diagnostic Interview (CIDI 3.0). Chronic physical conditions (arthritis, heart disease, respiratory disease, chronic back/neck pain, chronic headache, and diabetes) were ascertained using a standard checklist. Severe disability was defined as on or above the 90th percentile of the WMH version of the World Health Organization Disability Assessment Schedule (WHODAS-II).
The odds of severe disability among those with both mental disorder and each of the physical conditions (with the exception of heart disease) were significantly greater than the sum of the odds of the single conditions. The evidence for synergy was model dependent: it was observed in the additive interaction models but not in models assessing multiplicative interactions. Mental disorders were more likely to be associated with severe disability than were the chronic physical conditions.
This first cross-national study of the joint effect of mental and physical conditions on the probability of severe disability finds that co-morbidity exerts modest synergistic effects. Clinicians need to accord both mental and physical conditions equal priority, in order for co-morbidity to be adequately managed and disability reduced.
Co-morbidity; disability; interaction; mental; physical
Physical morbidity is a potent risk factor for depression onset and clearly increases with age, yet prior research has often found depressive disorders to decrease with age. This study tests the possibility that the relationship between age and mental disorders differs as a function of physical co-morbidity.
Eighteen general population surveys were carried out among household-residing adults as part of the World Mental Health (WMH) surveys initiative (n=42 697). DSM-IV disorders were assessed using face-to-face interviews with the Composite International Diagnostic Interview (CIDI 3.0). The effect of age was estimated for 12-month depressive and/or anxiety disorders with and without physical or pain co-morbidity, and for physical and/or pain conditions without mental co-morbidity.
Depressive and anxiety disorders decreased with age, a result that cannot be explained by organic exclusion criteria. No significant difference was found in the relationship between mental disorders and age as a function of physical/pain co-morbidity. The majority of older persons have chronic physical or pain conditions without co-morbid mental disorders; by contrast, the majority of those with mental disorders have physical/pain co-morbidity, particularly among the older age groups.
CIDI-diagnosed depressive and anxiety disorders in the general population decrease with age, despite greatly increasing physical morbidity with age. Physical morbidity among persons with mental disorder is the norm, particularly in older populations. Health professionals, including mental health professionals, need to address barriers to the management of physical co-morbidity among those with mental disorders.
Age; anxiety disorder; co-morbidity; depressive disorder; physical
South Africa’s history and current social conditions suggest that mental disorders are likely to be a major contributor to disease burden, but there has been no national study using standardized assessment tools.
The South African Stress and Health Study was a nationally representative in-person psychiatric epidemiological survey of 4351 adults (aged ≥18 years) that was conducted as part of the WHO World Mental Health (WMH) Survey Initiative between January 2002 and June 2004. Twelve-month prevalence and severity of DSM-IV disorders, treatment, and sociodemographic correlates were assessed with Version 3.0 of the WHO Composite International Diagnostic Interview (CIDI 3.0).
The 12-month prevalence of any DSM-IV/CIDI disorder was 16.5%, with 26.2% of respondents with disorder classified as severe cases and an additional 31.1% as moderately severe cases. The most common disorders were agoraphobia (4.8 %), major depressive disorder (4.9%) and alcohol abuse or dependence (4.5 %). Twenty-eight percent of adults with a severe or moderately severe disorder received treatment compared to 24.4% of mild cases. Some 13.8% of persons with no disorder received treatment. Treatment was mostly provided by the general medical sector with few people receiving treatment from mental health providers.
Psychiatric disorders are much higher in South Africa than in Nigeria and there is a high level of unmet need among persons with severe and moderately severe disorders.
Mental disorders; mental health services; South Africa
Studies of the impact of mental disorders on educational attainment are
rare in both high-income and low- and middle-income (LAMI) countries.
To examine the association between early-onset mental disorder and
subsequent termination of education.
Sixteen countries taking part in the World Health Organization World Mental
Health Survey Initiative were surveyed with the Composite International
Diagnostic Interview (n=41 688). Survival models were used to
estimate associations between DSM–IV mental disorders and subsequent
non-attainment of educational milestones.
In high-income countries, prior substance use disorders were associated
with non-completion at all stages of education (OR 1.4–15.2). Anxiety
disorders (OR=1.3), mood disorders (OR=1.4) and impulse control disorders
(OR=2.2) were associated with early termination of secondary education. In
LAMI countries, impulse control disorders (OR=1.3) and substance use disorders
(OR=1.5) were associated with early termination of secondary education.
Onset of mental disorder and subsequent non-completion of education are
consistently associated in both high-income and LAMI countries.
OBJECTIVE: To identify the number of people in the United States with untreated serious mental illness (SMI) and the reasons for their lack of treatment. DATA SOURCE/STUDY DESIGN: The National Comorbidity Survey; cross-sectional, nationally representative household survey. DATA COLLECTION: An operationalization of the SMI definition set forth in the Alcohol, Drug Abuse, and Mental Health Administration Reorganization Act identified individuals with SMI in the 12 months prior to the interview. The presence of SMI then was related to the use of mental health services in the past 12 months. PRINCIPAL FINDINGS: Of the 6.2 percent of respondents who had SMI in the year prior to interview, fewer than 40 percent received stable treatment. Young adults and those living in nonrural areas were more likely to have unmet needs for treatment. The majority of those who received no treatment felt that they did not have an emotional problem requiring treatment. Among those who did recognize this need, 52 percent reported situational barriers, 46 percent reported financial barriers, and 45 percent reported perceived lack of effectiveness as reasons for not seeking treatment. The most commonly reported reason both for failing to seek treatment (72 percent) and for treatment dropout (58 percent) was wanting to solve the problem on their own. CONCLUSIONS: Although changes in the financing of services are important, they are unlikely by themselves to eradicate unmet need for treatment of SMI. Efforts to increase both self-recognition of need for treatment and the patient centeredness of care also are needed.
Days out of role because of health problems are a major source of lost human capital. We examined the relative importance of commonly occurring physical and mental disorders in accounting for days out of role in 24 countries that participated in the World Health Organization (WHO) World Mental Health (WMH) surveys. Face-to-face interviews were carried out with 62 971 respondents (72.0% pooled response rate). Presence of ten chronic physical disorders and nine mental disorders was assessed for each respondent along with information about the number of days in the past month each respondent reported being totally unable to work or carry out their other normal daily activities because of problems with either physical or mental health. Multiple regression analysis was used to estimate associations of specific conditions and comorbidities with days out of role, controlling by basic socio-demographics (age, gender, employment status and country). Overall, 12.8% of respondents had some day totally out of role, with a median of 51.1 a year. The strongest individual-level effects (days out of role per year) were associated with neurological disorders (17.4), bipolar disorder (17.3) and post-traumatic stress disorder (15.2). The strongest population-level effect was associated with pain conditions, which accounted for 21.5% of all days out of role (population attributable risk proportion). The 19 conditions accounted for 62.2% of all days out of role. Common health conditions, including mental disorders, make up a large proportion of the number of days out of role across a wide range of countries and should be addressed to substantially increase overall productivity.
mental disorders; chronic disease; disability; productivity loss; prevalence; burden of disease