Pathways to comorbidity: the transition of pure mood, anxiety and substance use disorders into comorbid conditions in a longitudinal population-based study.

BACKGROUND: To describe transitions to comorbidity within a 3-year period in three cohorts of subjects with at baseline a 12-month pure mood, anxiety or substance use disorder but no lifetime history of any other disorder category. To assess the role of personal and social vulnerability factors, life events, clinical factors and functional disability in the pathway to comorbidity. METHODS: Data were derived from the Netherlands Mental Health Survey and Incidence Study (NEMESIS), a prospective epidemiologic study of a representative sample of 7076 adults aged 18-65, interviewed in three waves (baseline, 1 and 3 years after baseline) with the Composite International Diagnostic Interview. RESULTS: 15.2% of 99 pure mood, 10.5% of 220 anxiety and 6.8% of 192 substance use disorder cases became comorbid. Comorbid transition from pure mood disorder was multivariately associated with higher age, external mastery and severity of the disorder. Comorbidity developing from pure anxiety disorder was associated with past and recent stressful life circumstances (childhood trauma, negative life events) and physical functional disability. Predictors of comorbid transition from pure substance use disorder were personal and social vulnerability variables only (high neuroticism, low social support). LIMITATIONS: Although NEMESIS was performed among a substantial number of cases, the number of cases with a pure disorder at baseline subsequently developing comorbidity was low. This limited analysing determinants of different comorbid conditions. CONCLUSIONS: Risk factors for comorbid transitions vary depending on whether subjects have a primary mood, anxiety or substance use disorder. Interventions aimed at primary prevention of comorbidity to reduce psychiatric burden in populations with a history of pure disorders are indicated in response to clearly identified risk factors.

Determinants of persistence of major depressive episodes in the general population. Results from the Netherlands Mental Health Survey and Incidence Study (NEMESIS).

BACKGROUND: Data on determinants of persistence of major depressive episodes (MDE) are inconsistent due to methodological shortcomings of the studies involved. AIMS: To examine determinants of persistence of MDE in subjects from the general population (N=250) with new episodes of DSM-III-R major depression. METHOD: The Netherlands Mental Health Survey and Incidence Study is a prospective epidemiologic survey in the adult population (N=7076), using the Composite International Diagnostic Interview (CIDI). A broad range of potential determinants was assessed. RESULTS: Determinants of persistence were severity of the index episode, longer duration of previous episodes, (chronic) physical illness and lack of social support. A recurrent episode predicted shorter duration. LIMITATIONS: Follow-up was only 2 years and duration of episode was retrospectively assessed. CONCLUSIONS: Just as in clinical populations, illness-related factors seem to be the strongest predictors of persistence of MDE. A thorough assessment of each depressed patient on the predictors of persistence is advisable.

The epidemiology of major depressive episodes: results from the International Consortium of Psychiatric Epidemiology (ICPE) Surveys.

Absence of a common diagnostic interview has hampered cross-national syntheses of epidemiological evidence on major depressive episodes (MDE). Community epidemiological surveys using the World Health Organization Composite International Diagnostic Interview administered face-to-face were carried out in 10 countries in North America (Canada and the US), Latin America (Brazil, Chile, and Mexico), Europe (Czech Republic, Germany, the Netherlands, and Turkey), and Asia (Japan). The total sample size was more than 37,000. Lifetime prevalence estimates of hierarchy-free DSM-III-R/DSM-IV MDE varied widely, from 3% in Japan to 16.9% in the US, with the majority in the range of 8% to 12%. The 12-month/lifetime prevalence ratio was in the range 40% to 55%, the 30-day/12-month prevalence ratio in the range 45% to 65%, and median age of onset in the range 20 to 25 in most countries. Consistent socio-demographic correlates included being female and unmarried. Respondents in recent cohorts reported higher lifetime prevalence, but lower persistence than those in earlier cohorts. Major depressive episodes were found to be strongly co-morbid with, and temporally secondary to, anxiety disorders in all countries, with primary panic and generalized anxiety disorders the most powerful predictors of the first onset of secondary MDE. Major depressive episodes are a commonly occurring disorder that usually has a chronic-intermittent course. Effectiveness trials are needed to evaluate the impact of early detection and treatment on the course of MDE as well as to evaluate whether timely treatment of primary anxiety disorders would reduce the subsequent onset, persistence, and severity of secondary MDE.

The prevalence of treated and untreated mental disorders in five countries.

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.

Do urbanicity and familial liability coparticipate in causing psychosis?

OBJECTIVE: The urban environment and familial liability are risk factors for psychotic illness, but it is not known whether a biological synergism exists between these two proxy causes. METHOD: The amount of biological synergism between familial liability (defined as a family history of delusions and/or hallucinations necessitating psychiatric treatment) and a five-level rating of population density of place of residence was estimated from the additive statistical interaction in a general population risk set of 5,550 individuals. RESULTS: Both the level of urbanicity (adjusted summary odds ratio=1.57, 95% CI=1.30-1.89) and familial liability (adjusted odds ratio=4.59, 95% CI=2.41-8.74) increased the risk for psychotic disorder, independently of each other. However, the effect of urbanicity on the additive scale was much larger for individuals with evidence of familial liability (risk difference=2.58%) than in those without familial liability (risk difference=0.40%). An estimated 60%-70% of the individuals exposed to both urbanicity and familial liability had developed psychotic disorder because of the synergistic action of the two proxy causes. CONCLUSIONS: Given that familial clustering of psychosis is thought to reflect the effect of shared genes, the findings support a mechanism of gene-environment interaction in the causation of psychosis.

Same-sex sexuality and quality of life: findings from the Netherlands Mental Health Survey and Incidence Study.

This study assessed differences in quality of life (QL) between homosexual and heterosexual people and attempted to identify factors accounting for observed differences. Data were collected in a representative sample of the Dutch population aged 18-64 (N = 7,076). Classification as heterosexual or homosexual was based upon reported sexual behavior in the preceding year; 84.8% of the total sample (N = 5,998) could be classified: 2.8% of 2,878 sexually active men and 1.4% of 3,120 sexually active women had had same-sex partners. Differences in QL were tested by analysis of variance. Factors accounting for observed differences in QL were identified by selecting determinants of QL on which homosexual and heterosexual people differed and including them with same-sex sexuality in multiple regression analyses. Homosexual men, but not women, differed from their heterosexual counterparts on various dimensions of QL. Lesser QL in homosexual men was predominantly explained by self-esteem and mastery. Same-sex sexuality contributed independently to some of the observed differences. Although same-sex sexuality is related to QL in men, the lack of association in women suggests that the link is mediated by other factors, indicating the need to explore in what respect the situation of homosexual men and women differs. This study also suggests the importance of finding out how lower sense of self-esteem and of mastery come about in homosexual men.

Bulimia nervosa following psychological and multiple child abuse: support for the self-medication hypothesis in a population-based cohort study.

OBJECTIVE: To unravel the complex role of child abuse as a risk factor for bulima nervosa (BN), from the perspective of the self-medication hypothesis which asserts that in abused BN cases binge eating is primarily a way of coping with the anxiety or mood disorders that stem from the abuse. METHOD: In a population-based study (N = 1,987) DSM-III-R diagnoses were assessed with the CIDI. Differences in exposure rates to child abuse between BN cases versus healthy, psychiatric, substance use, and dual diagnosis controls were employed to test the self-medication hypothesis. RESULTS: A history of psychological or multiple abuse was found to be a specific risk factor for dual diagnosis disorder (cases with psychiatric and substance use disorders) and for BN. Nearly all BN cases that experienced multiple or psychological child abuse, showed such comorbid anxiety or mood disorders. DISCUSSION: We found tentative support for the self-medication hypothesis.

Duration of major depressive episodes in the general population: results from The Netherlands Mental Health Survey and Incidence Study (NEMESIS).

BACKGROUND: Data on the duration of major depressive episodes (MDE) in the general population are sparse. AIMS: To assess the duration of MDE and its clinical and socio-demographic determinants in a study group drawn from the general population with newly originated episodes of major depression. METHOD: The Netherlands Mental Health Survey and Incidence Study is a prospective epidemiological survey in the adult population (n=7076), using the Composite International Diagnostic Interview. Duration of MDE over 2 years was assessed with a Life Chart Interview. RESULTS: The median duration of MDE was 3.0 months; 50% of participants recovered within 3 months, 63% within 6 months, 76% within 12 months and nearly 20% had not recovered at 24 months. Determinants of persistence were severity of depression and comorbid dysthymia. A recurrent episode predicted shorter duration. CONCLUSIONS: Although half of those affected with MDE recovered rapidly, the risk of chronicity (duration 24 months or more) was considerable. This underlines the necessity of diagnosing and treating those at risk.

Gender and age-specific first incidence of DSM-III-R psychiatric disorders in the general population. Results from the Netherlands Mental Health Survey and Incidence Study (NEMESIS).

BACKGROUND: Prospective studies in the general population are needed to identify risk factors for mental disorders. Samples of sufficient size are needed, but large-scale studies that assess the incidence of psychopathology are rare. AIMS: The aim of this study was to investigate the 12-month first incidence rates (IR) by age and gender for 15 specified DSM-III-R disorders in the general population. Methods The study was based on a representative sample (N = 5618) of the Dutch population aged 18-64. RESULTS: The IR for any disorder was 5.68 per 100 person-years at risk (men 4.45, women 6.94). IRs for both men and women were highest in the youngest age category. The most common 12-month incident disorders in men were alcohol abuse (IR = 4.09) and major depression (1.72). In women, the most common incident disorders were major depression (IR = 3.90) and simple phobia (3.17). CONCLUSIONS: The results show the rarity of first-onset of mental disorders. IRs vary strongly between the different life phases, as well as between men and women. This suggests potential target areas for age-specific and gender-specific prevention.

Neuroticism and low self-esteem as risk factors for psychosis.

BACKGROUND: Low self-esteem and high neuroticism are common features in psychosis, but in the absence of longitudinal studies it is unclear whether they represent consequences of the illness or risk factors acting before illness onset. METHODS: A population sample of 3,929 individuals with no lifetime evidence of psychosis were interviewed with the Composite International Diagnostic Interview and were administered the Groningen Neuroticism Scale and the Rosenberg Self-Esteem Scale at baseline and 1 and 3 years later. At year 3, individuals with CIDI evidence of psychotic symptoms were interviewed by clinicians to identify incident psychotic or psychosis-like symptoms. RESULTS: Baseline neuroticism and self-esteem predicted first-ever onset of psychotic symptoms at year 3 (neuroticism, OR 1.16, 95% CI 1.09, 1.23; self-esteem, OR 1.09, 95% CI 1.01, 1.18).When adjusted for each other and for level of anxiety and depression, neuroticism was the strongest independent predictor for onset of psychotic symptoms (OR 1.16, 95% CI 1.07, 1.26). CONCLUSIONS: Neuroticism increases the risk for development of psychotic symptoms. Mechanisms of risk may involve certain cognitive styles associated with neuroticism, such as beliefs about the uncontrollability of certain events and experiences. The association between low self-esteem and psychosis may involve the area of overlap between self-esteem and neuroticism.

Psychiatric disorders in adult children of parents with a history of psychopathology.

BACKGROUND: The relation between major categories of psychiatric problems in parents and psychiatric disorders in their adult children has been investigated in only a few community studies. METHODS: In this study, data from a representative sample of the Dutch population (N = 7147) (response rate: 69.7 %) were used to examine this relation. DSM-III-R disorders were assessed using the CIDI. Parental psychiatric symptoms and childhood adversities were assessed using self-report measures. RESULTS: It was found that psychiatric symptoms in parents are strongly related to psychiatric disorders in their (adult) children, independent of type of parental psychiatric symptom. Only maternal problem drinking was not significantly related to an increased risk for their children. When controlled for childhood adversities and demographic variables, most relations between psychiatric disorders and parental psychiatric symptoms remained significant. Parental anxiety symptoms, however, were not significantly related to psychiatric disorders in the children, including anxiety disorders. It was also found that anxiety disorders in the children were not related to most parental psychiatric symptoms. CONCLUSIONS: This study has once more made it clear that children whose parents have psychiatric problems constitute an important high-risk group and that prevention and early intervention in these children constitute an important public health issue.

Risk factors for 12-month comorbidity of mood, anxiety, and substance use disorders: findings from the Netherlands Mental Health Survey and Incidence Study.

OBJECTIVE: This study examined risk factor profiles of pure and comorbid 12-month mood, anxiety, and substance use disorder in the general population. METHOD: Data were derived from the Netherlands Mental Health Survey and Incidence Study, a prospective epidemiologic study in which a representative sample of 7,076 adults age 18-64 years were interviewed with the Composite International Diagnostic Interview. Logistic regression was used to compare subjects with a diagnosis of pure and comorbid disorders with non-psychopathological comparison subjects and to compare subjects with comorbid disorders with those with pure disorder on sociodemographic characteristics, chronic somatic conditions, parental psychiatric history, and childhood traumas and adversities. RESULTS: Only 39.5% of the subjects with a 12-month mood disorder, 59.3% of those with an anxiety disorder, and 75.4% of those with a substance use disorder exhibited the disorder in the pure form. Comorbid anxiety and mood disorders, the most prevalent comorbid condition, showed associations with eight of the nine sociodemographic and long-term vulnerability factors investigated; pure mood disorder and pure anxiety disorder were each linked to only about half of the factors. Female gender, younger age, lower educational level, and unemployment were associated with comorbid anxiety and mood disorders but not with pure mood disorders. The risk profiles of pure anxiety disorder and pure substance use disorder similarly diverged from those of the comorbid conditions. CONCLUSIONS: High levels of psychiatric comorbidity exist in the general population. The risk factor profiles for comorbid disorders differ considerably from those for pure disorders. Primary prevention of secondary disorders in populations with a history of a primary disorder are important for reducing psychiatric burden.

Determinants of mental distress in adults with a severe auditory impairment: differences between prelingual and postlingual deafness.

OBJECTIVE: To investigate the determinants of mental health among severe hearing-impaired adults in the Netherlands, separately by prelingual and postlingual age of onset. METHODS: Five hundred twenty-three face-to-face interviews were carried out by persons with practical skills in communication with hearing-impaired people. RESULTS: Of prelingually and postlingually deaf men, 27.1% and 27.7%, respectively, reported mental distress (scores on the General Health Questionnaire > or = 2), and among women these figures were 32.4% and 43.2%. These rates are higher than in the general population (men: 22.0%; women: 26.6%). Among the prelingual category, none of the demographic or hearing loss-related characteristics was associated with mental health status as measured by the General Health Questionnaire (GHQ). Of these variables, only additional impairment or serious illness was associated with the brief Symptom Checklist (SCL-8D). Among the postlingual category, female gender and equilibrium disturbance was associated with both the GHQ and SCL-8D, and additional impairment or serious illness with the SCL-8D. For both categories, the risk of mental distress also was higher in those with more communication problems, lower levels of self-esteem, and poorer acceptance of the hearing loss. Opportunities for identification in youth and social support were not associated with mental health. CONCLUSIONS: Mental health status differs between the hearing-impaired and the general population, but not as much as is sometimes suggested. Mental distress is greater in those in certain categories of the hearing-impaired.