The economic burden of mental disorders: results from the Netherlands mental health survey and incidence study-2

OBJECTIVE

Currently, there is a paucity of up-to-date estimates of the economic burden caused by mental disorders. Such information could provide vital insight into one of the most serious and costly-yet to some extent preventable-health challenges facing the world today.

METHOD

Data from a national psychiatric-epidemiological cohort study (NEMESIS-2, N = 6506) were used to provide reliable, relevant, and up-to-date cost estimates (in 2019 Euro) regarding healthcare costs, productivity losses, and patient and family costs associated with DSM-IV mental disorders both at individual level, but also in the general population and in the workforce of the Netherlands (per 1 million population).

RESULTS

In the general population, the costs of mood disorders, specifically depression, are substantial and rank above those from the anxiety disorders, whilst costs of anxiety disorders are more substantial than those stemming from substance use disorders, even when the per-person costs of drug abuse appear highest of all. In the workforce, specific and social phobias are leading causes of excess costs. The workforce has lower healthcare costs but higher productivity costs than general population.

DISCUSSION

The findings suggest that (preventive) healthcare interventions targeting the workforce are likely to become cost-effective and underscore the importance for employers to create healthy work environments. Overall, the results highlight the need to strengthen the role of mental health promotion and prevention of mental disorders in the social domain before people require treatment to reduce the staggering and costly burden caused by mental disorders to individuals and society.

[The relation between sleep problems and the onset and course of anxiety and mood disorders]

BACKGROUND

Sleep gets little attention in mental health care treatments. Epidemiological research with regards to the association between sleep problems and anxiety and mood disorders can contribute to good clinical decision making.

AIM

Based on data from the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2), we examined the relation between sleep problems and first onset, recurrence and persistence of anxiety and mood disorders within a 3 year period.

METHOD

Different groups of respondents were selected to examine the relation between sleep problems and different stages of anxiety and mood disorders within three years. DSM-IV diagnoses were determined using the Composite International Diagnostic Interview (CIDI 3.0) and sleep problems with the Women’s Health Initiative Insomnia Rating Scale (IRS; ≥ 9). Logistic regression was performed. Multivariable analysis took into account a large number of potentially confounding variables.

RESULTS

Almost a quarter of the respondents without an anxiety or mood disorder and almost half of the respondents with an anxiety or mood disorder experience sleep problems. In the multivariable analysis, sleep problems were associated with recurrence of an anxiety disorder (OR 2.10; 95% CI 1.31-3.38), but not with the first onset and persistence of an anxiety disorder. Furthermore, sleep problems appear to be associated with the first onset of a mood disorder (OR 2.18; 95% CI 1.27-3.74) and with the persistence of a mood disorder (OR 2.51; 95% CI 1.17-5.37), but not with recurrence of this disorder.

CONCLUSION

The results underline the importance of identifying sleep problems of people with (an increased risk of) anxiety and mood disorders. The treatment of sleep problems may contribute to a reduced incidence of these mental disorders and a better and sustainable recovery.

Impact of borderline personality disorder traits on the association between age and health-related quality of life: A cohort study in the general population

Background

Increasing age as well as borderline personality pathology are associated with a lower level of health-related quality of life (HR-QoL). Our objective was to investigate whether the presence of borderline personality traits modifies the association between age and HR-QoL in the general population.

Methods

Cross-sectional data from 5,303 respondents (aged 21–72 years) of the Netherlands Mental Health Survey and Incidence Study-2 were analyzed. Borderline personality traits were assessed with the International Personality Disorder Examination questionnaire. Mental and physical HR-QoL were measured with the Medical Outcomes Study Short Form Health Survey. Multiple linear regression analysis was used to examine the association of borderline personality traits, age and their interaction on mental as well as physical HR-QoL, adjusted for demographic variables as well as somatic and mental disorders.

Results

A total of 1,520 (28.7%) respondents reported one or more borderline personality traits of which 58 (1.1%) reported five or more indicative of a borderline personality disorder. A higher age was associated with lower physical HR-QoL. This negative association became significantly stronger in the presence of borderline personality traits. The association between increasing age and mental HR-QoL was positive in the absence of borderline personality traits and negative in the presence of borderline personality traits.

Conclusion

Borderline personality traits negatively interfere with the association between age and HR-QoL irrespective of somatic and mental disorders. Attention of clinicians and researchers for subthreshold borderline personality pathology is needed in middle-aged and older persons.

[Recurrence and chronicity of major depressive disorder in the general population: results from the Netherlands Mental Health Survey and Incidence Study-2]

The naturalistic course of major depressive disorder (mdd) and risk indicators for recurrence and chronicity of mdd are best investigated using a psychiatric epidemiological population study without clear selection bias. However, such studies are scarce, thereby limiting clinical decision-making concerning the monitoring and maintenance of treatment.<br/> AIM: To present findings from the Netherlands Mental Health Survey and Incidence Study-2 (nemesis-2) regarding the recurrence and chronicity of mdd and associated risk indicators in the general population.<br/> METHOD: At baseline, two groups were selected to examine the recurrence and chronicity of mdd at follow-up. Diagnoses were assessed with the Composite International Diagnostic Interview (cidi) 3.0.<br/> RESULTS: Among respondents with remitted mdd (n = 746), the cumulative recurrence rate was 4.3% at 5 years, 13.4% at 10 years, and 27.1% at 20 years. Time to recurrence was predicted by vulnerability characteristics (childhood abuse, negative life events, parental psychopathology), physical health, functioning, clinical characteristics of depression (previous episodes, severity, medication use), psychiatric comorbidity and mental health use. Among respondents with current mdd (n = 242), 12% developed a chronic depressive episode over 6 years. The chronic course was predicted by risk indicators similar to those for recurrence, except for vulnerability characteristics and physical health.<br/> CONCLUSION: These risk indicators may help identify depressive patients requiring monitoring and who might benefit from preventive interventions or maintenance treatment.

Functioning before and after a major depressive episode: pre-existing vulnerability or scar? A prospective three-wave population-based study

BACKGROUND

The vulnerability hypothesis suggests that impairments after remission of depressive episodes reflect a pre-existing vulnerability, while the scar hypothesis proposes that depression leaves residual impairments that confer risk of subsequent episodes. We prospectively examined vulnerability and scar effects in mental and physical functioning in a representative Dutch population sample.

METHODS

Three waves were used from the Netherlands Mental Health Survey and Incidence Study-2, a population-based study with a 6-years follow-up. Mental and physical functioning were assessed with the Medical Outcomes Study Short Form (SF-36). Major depressive disorder (MDD) was assessed with the Composite International Diagnostic Interview 3.0. Vulnerability effects were examined by comparing healthy controls (n = 2826) with individuals who developed a first-onset depressive episode during first follow-up but did not have a lifetime diagnosis of MDD at baseline (n = 181). Scarring effects were examined by comparing pre- and post-morbid functioning in individuals who developed a depressive episode after baseline that was remitted at the third wave (n = 108).

RESULTS

Both mental (B = -5.4, s.e. = 0.9, p < 0.001) and physical functioning (B = -8.2, s.e. = 1.1, p < 0.001) at baseline were lower in individuals who developed a first depressive episode after baseline compared with healthy controls. This effect was most pronounced in people who developed a severe episode. No firm evidence of scarring in mental or physical functioning was found. In unadjusted analyses, physical functioning was still lowered post-morbidly (B = -5.1, s.e. = 2.1, p = 0.014), but this effect disappeared in adjusted analyses.

CONCLUSIONS

Functional impairments after remission of depression seem to reflect a pre-existing vulnerability rather than a scar.

Recurrence and chronicity of major depressive disorder and their risk indicators in a population cohort

OBJECTIVE

The naturalistic course of major depressive disorder (MDD) and risk indicators for recurrence and chronicity are best studied using a population sample without clear selection bias. However, such studies are scarce. This limits clinical decision-making concerning monitoring and maintenance treatment.

METHOD

Data were used from the Netherlands Mental Health Survey and Incidence Study-2, a psychiatric epidemiological cohort study among a representative adult population. Two groups at baseline were selected to study recurrence and chronicity of MDD at follow-up. Diagnoses were assessed with the Composite International Diagnostic Interview 3.0.

RESULTS

Among remitted MDD cases (n = 746), the cumulative recurrence rate was 4.3% at 5 years, 13.4% at 10 years and 27.1% at 20 years. Time to recurrence was predicted by vulnerability characteristics (childhood abuse, negative life events, parental psychopathology), physical health, functioning, clinical characteristics of depression (previous episodes, severity, medication use), psychiatric comorbidity and mental health use. Among current MDD cases (n = 242), 12% developed a chronic depressive episode over 6 years. Chronic course was predicted by similar risk indicators as recurrence, except for vulnerability characteristics and physical health.

CONCLUSION

These risk indicators may help to identify patients requiring monitoring and who could benefit from preventive interventions or maintenance treatment.

[Abortion and the risk of mental disorders]

Research into the potential mental health consequences of abortion yields inconsistent results and is characterized by methodological limitations.<br /> AIM: To offer a more conclusive insight into women's mental health after an abortion by stringently taking both pre-abortion mental health and confounding covariates into account.<br /> METHOD: A prospective longitudinal cohort study, the Dutch Abortion and Mental Health Study (DAMHS), through which women with and without abortion experiences could be compared. The study was designed in a similar way to the large scale Dutch population study into mental health of the Trimbos Institute, the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2).<br /> RESULTS: Women who had an abortion were significantly more likely to have had previous DSM-IV mental disorders. Psychiatric history appeared to be associated with how women experienced and handled the unwanted pregnancy and abortion. A prior history of mental disorders, averse recent life events or an unstable partner relationship increased the risk of developing post abortion mental disorders, while experiencing an abortion did not.<br /> CONCLUSION: Women who have had an abortion more often have a history of mental disorders, yet there is no evidence that an abortion in itself would increase the risk of developing a mental disorder.

[New numbers on the duration of major and minor depressive episodes in the general population; results from NEMESIS-2]

Relatively little research has been conducted that can reliably be used by psychiatrists, psychologists and general practitioners to estimate the recovery time of their patients suffering from depression. The treatment guideline for depression submits that half of those with mdd will recover within three months.<br /> AIM: To present the findings from nemesis-2 (the Netherlands Mental Health Survey and Incidence Study-2) on both the duration of depressive episodes in the general population and associated risk indicators.<br /> METHOD: The respondents that had developed a depressive episode between the first two follow-up assessments were selected; 286 with a clinical depression according to dsm-iv criteria (mdd) and 107 with a subclinical depression (MinDD). The episode duration was assessed with the Life Chart Interview.<br /> RESULTS: Half of the patients with mdd recovered within 6 months and 12% had not recovered after 3 years. The mean duration for mdd was 10.7 months. Better physical and mental health before depression onset predicted shorter duration. Longer duration was associated with comorbid dysthymia or anxiety disorder. In comparison, the median duration of MinDD was half the length of mdd (3 months), whereas the mean duration (8.7 months), the percentage that had not recovered after 3 years (10%) and risk indicators for episode duration hardly differed.<br /> CONCLUSION: In the guideline for depression it is assumed that half of those with mdd will recover within three months. Our study, however, found the median duration of mdd to be twice as long. Consequently, only a short period without active treatment can be justified. This paper also concludes that MinDD cannot be regarded as a transient, self-limiting mood state.

Duration of major and minor depressive episodes and associated risk indicators in a psychiatric epidemiological cohort study of the general population

OBJECTIVE

Hardly any studies exist on the duration of major depressive disorder (MDD) and factors that explain variations in episode duration that lack biases. This limits clinical decision-making and leaves patients wondering when they will recover.

METHOD

Data were used from the Netherlands Mental Health Survey and Incidence Study-2, a psychiatric epidemiological cohort study among a nationally representative adult population. Respondents with a newly originated depressive episode were selected: 286 MDD and 107 minor depressive disorder (MinDD) cases. DSM-IV diagnoses were assessed with the Composite International Diagnostic Interview 3.0 and episode duration with the Life Chart Interview.

RESULTS

Among MDD cases, median episode duration was 6 months, mean duration was 10.7 months, and 12% had not recovered at 36 months. Longer duration was associated with comorbid dysthymia, anxiety disorder, psychotropic medication use (i.e. antidepressants or benzodiazepines prescribed by a mental health professional), mental health care use and suicidal behaviour. Better physical and mental functioning before depression onset predicted shorter duration. Among MinDD cases, shorter median duration (3 months) but similar mean duration (8.7 months), risk of chronicity (10% not recovered at 36 months) and risk indicators for episode duration were found.

CONCLUSION

As the risk of chronicity was similar for MDD and MinDD, MinDD cannot be dismissed as a merely brief mood state.

A cluster analysis of early onset in common anxiety disorders

Early onset is regarded as an important characteristic of anxiety disorders, associated with higher severity. However, previous findings diverge, as definitions of early onset vary and are often unsubstantiated. We objectively defined early onset in social phobia, panic disorder, agoraphobia, and generalised anxiety disorder, using cluster analysis with data gathered in the general population. Resulting cut-off ages for early onset were ≤22 (social phobia), ≤31 (panic disorder), ≤21 (agoraphobia), and ≤27 (generalised anxiety disorder). Comparison of psychiatric comorbidity and general wellbeing between subjects with early and late onset in the general population and an outpatient cohort, demonstrated that among outpatients anxiety comorbidity was more common in early onset agoraphobia, but also that anxiety- as well as mood comorbidity were more common in late onset social phobia. A major limitation was the retrospective assessment of onset. Our results encourage future studies into correlates of early onset of psychiatric disorders.

Mental disorders among college students in the World Health Organization World Mental Health Surveys

BACKGROUND

Although mental disorders are significant predictors of educational attainment throughout the entire educational career, most research on mental disorders among students has focused on the primary and secondary school years.

METHOD

The World Health Organization World Mental Health Surveys were used to examine the associations of mental disorders with college entry and attrition by comparing college students (n = 1572) and non-students in the same age range (18-22 years; n = 4178), including non-students who recently left college without graduating (n = 702) based on surveys in 21 countries (four low/lower-middle income, five upper-middle-income, one lower-middle or upper-middle at the times of two different surveys, and 11 high income). Lifetime and 12-month prevalence and age-of-onset of DSM-IV anxiety, mood, behavioral and substance disorders were assessed with the Composite International Diagnostic Interview (CIDI).

RESULTS

One-fifth (20.3%) of college students had 12-month DSM-IV/CIDI disorders; 83.1% of these cases had pre-matriculation onsets. Disorders with pre-matriculation onsets were more important than those with post-matriculation onsets in predicting subsequent college attrition, with substance disorders and, among women, major depression the most important such disorders. Only 16.4% of students with 12-month disorders received any 12-month healthcare treatment for their mental disorders.

CONCLUSIONS

Mental disorders are common among college students, have onsets that mostly occur prior to college entry, in the case of pre-matriculation disorders are associated with college attrition, and are typically untreated. Detection and effective treatment of these disorders early in the college career might reduce attrition and improve educational and psychosocial functioning.

The functional and clinical relevance of childhood trauma-related admixture of affective, anxious and psychosis symptoms

OBJECTIVE

Previous work has shown that across different patient samples, patients with childhood trauma are more likely to have co-occurrence of affective, anxious and psychosis symptoms than non-traumatized patients. However, the clinical relevance of trauma-related admixture remains to be established.

METHOD

We examined patients with mood disorder (NEMESIS-2; n = 1260), anxiety disorder (NEMESIS-2; n = 896) or psychotic disorder (GROUP; n = 532) in terms of symptom profiles, quality of life (QOL) and social functioning.

RESULTS

Results showed that mood disorder patients with both trauma and co-occurrence of affective, anxious and psychosis symptoms had a lower QOL (B-12.6, 95% CI -17.7 to -7.5, P < 0.001), more help-seeking behaviour [odds ratio (OR) 2.5, 95% CI 1.1-5.7, P = 0.031] and higher prevalence of substance use disorders (OR 7.8, 95% CI 1.1-58.0, P = 0.044), compared with patients without trauma history and symptom admixture (Trauma-/CL-). Similar results were found in patients with an anxiety disorder. Traumatized patients with a psychotic disorder and admixture showed lower QOL (B-0.6, 95% CI -0.9 to -0.4, P < 0.001), higher prevalence of drug disorders (OR 2.2, 95% CI 1.2-3.9, P = 0.008) and lower global assessment of functioning (B-12.8, 95% CI -17.1 to -8.5, P < 0.001) than Trauma-/CL- patients.

CONCLUSION

Stratification according to childhood trauma exposure thus identifies a phenotype characterized by admixture of affective, anxiety and psychotic symptoms that, when combined, has clinical relevance. Identification of functionally meaningful aetiological subgroups may aid clinical practice.

[Child maltreatment: long-term economic consequences and implications]

Child maltreatment occurs frequently. This has detrimental effects later in life on mental health and is linked to considerable costs due to health care use and sick leave. Self-mastery, however, is a factor that may well mitigated the effects of child maltreatment . <br/> AIM: To quantify the long-term costs of child abuse and to test the hypothesis that self-mastery can modify the after-effects of maltreatment .<br/> METHOD: Data were obtained from a psychiatric cohort study (n=5618). The risk factors were emotional neglect and mental, physical and sexual abuse before the age of 16.<br/> RESULTS: When individuals are about 39 years old, the various forms of maltreatment to which they were subjected as children are associated with substantially higher health care costs and frequent absenteeism. Higher levels of self-mastery achieved in childhood were indeed associated with lower costs in adulthood. <br/> CONCLUSION: Child maltreatment costs the Netherlands millions of euros annually because it leads to higher health care costs and more frequent sick leave. Active steps to curb child abuse are of both financial and economic significance. More training in self-mastery could perhaps be helpful, but further research is needed in this area.

Gender differences in psychotropic use across Europe: Results from a large cross-sectional, population-based study

BACKGROUND

In many epidemiological studies, women have been observed to consume psychotropic medication more often than men. However, the consistency of this relationship across Europe, with differences in mental health care (MHC) resources and reimbursement policies, is unknown.

METHODS

Questions on 12-month psychotropic use (antidepressants, benzodiazepines, antipsychotics, mood stabilizers) were asked to 34,204 respondents from 10 European countries of the EU-World Mental Health surveys. Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) criteria were used to determine 12-month prevalence of mood/anxiety disorders using the Composite International Diagnostic Interview (v3.0).

RESULTS

For all participating countries, women were significantly more likely than men to use psychotropic medication within the previous 12 months (overall-OR=2.04, 95% CI: 1.81-2.31). This relationship remained significant after adjusting for common sociodemographic factors (age, income level, employment status, education, marital status) and country-level indicators (MHC provision, private household out-of-pocket expenditure, and Gender Gap Index). In multivariable gender-stratified risk-factor analysis, both women and men were more likely to have taken psychotropic medication with increasing age, decreasing income level, and mental health care use within the past 12 months, with no significant differences between genders. When only including participants with a mental disorder, gender differences overall were still significant with any 12-month mood disorder but not with any 12-month anxiety disorder, remaining so after adjusting for sociodemographic characteristics and country-level indicators.

CONCLUSIONS

Women use psychotropic medication consistently more often than men, yet reasons for their use are similar between genders. These differences also appear to be contingent on the specific mental disorder.

Childhood trauma is associated with a specific admixture of affective, anxiety, and psychosis symptoms cutting across traditional diagnostic boundaries

BACKGROUND

Meta-analyses link childhood trauma to depression, mania, anxiety disorders, and psychosis. It is unclear, however, whether these outcomes truly represent distinct disorders following childhood trauma, or that childhood trauma is associated with admixtures of affective, psychotic, anxiety and manic psychopathology throughout life.

METHOD

We used data from a representative general population sample (NEMESIS-2, n = 6646), of whom respectively 1577 and 1120 had a lifetime diagnosis of mood or anxiety disorder, as well as from a sample of patients with a diagnosis of schizophrenia (GROUP, n = 825). Multinomial logistic regression was used to assess whether childhood trauma was more strongly associated with isolated affective/psychotic/anxiety/manic symptoms than with their admixture.

RESULTS

In NEMESIS-2, largely comparable associations were found between childhood trauma and depression, mania, anxiety and psychosis. However, childhood trauma was considerably more strongly associated with their lifetime admixture. These results were confirmed in the patient samples, in which it was consistently found that patients with a history of childhood trauma were more likely to have a combination of multiple symptom domains compared to their non-traumatized counterparts. This pattern was also found in exposed individuals who did not meet criteria for a psychotic, affective or anxiety disorder and who did not seek help for subclinical psychopathology.

CONCLUSIONS

Childhood trauma increases the likelihood of a specific admixture of affective, anxiety and psychotic symptoms cutting across traditional diagnostic boundaries, and this admixture may already be present in the earliest stages of psychopathology. These findings may have significant aetiological, pathophysiological, diagnostic and clinical repercussions.

Clustering of health risk behaviours and the relationship with mental disorders

BACKGROUND

Health risk behaviours tend to co-occur and are found to be related to mental health symptoms. This is the first study to identify health behaviour clusters in relation to mental disorders.

METHODS

Data were used from the second wave of the Netherlands Mental Health Survey and Incidence Study (NEMESIS-2), a nationally representative sample of adults (n=5303). Latent class analysis was performed to identify clusters based on four health risk behaviours (smoking, heavy drinking, physical inactivity, and unhealthy diet). Concurrently, we examined the relationship between the identified clusters and a range of DSM-IV diagnoses, assessed with the Composite International Diagnostic Interview 3.0.

RESULTS

Four distinct health behaviour clusters were identified: most healthy (mainly non-smokers, moderate drinkers, active, healthy diet; class 1: 79.3%); smokers, moderate drinkers, inactive, unhealthy diet (class 2: 13.2%); smokers, heavy episodic drinkers, active, unhealthy diet (class 3: 3.8%); Smokers, frequent heavy drinkers, active, low fruit (class 4: 3.6%). Despite their different lifestyles, individuals in all three unhealthy clusters had double the risk of depression. Unhealthy behaviour clusters were strongly associated with drug dependence (classes 2 and 3), alcohol abuse and dependence (classes 3 and 4), and social phobia (class 4).

LIMITATIONS

Due to the cross-sectional design, no conclusions about the causality of the relationship between HRB clusters and mental disorders can be drawn from the current study.

CONCLUSIONS

Health behaviour clusters are strongly associated with mental disorders. This co-existence of behaviours and disorders emphasises the importance of an integrative approach in the prevention of mental illnesses.

[The attitude of the general public towards (discharged) psychiatric patients: results from NEMESIS-2]

BACKGROUND

In the Netherlands there is no up-to-date information about the attitude of the public to (discharged) psychiatric patients. Also, very little is known about which population groups hold stigmatising views.

AIM

To measure the public's attitudes to (discharged) psychiatric patients and to find out whether these attitudes differ according to the background characteristics (e.g. demographics, respondent's psychiatric history).

METHOD

In our study we used attitudes collected via the Netherlands Mental Health Survey and Incidence Study-2, a psychiatric epidemiological study of the adult general population (n = 6646; aged 18-64 years). The psychiatric history of the respondents was assessed by means of the Composite International Diagnostic Interview 3.0.

RESULTS

More than 70% of the respondents stated that they had no objection to having a (discharged) psychiatric patient as a neighbour, friend or colleague. However, their ´willingness´ declined markedly, namely to less than 30%, when they were asked if they would be willing to have a (discharged) psychiatric patient as their son-in-law or baby-sitter. A comparison with other earlier Dutch studies indicates that since 1987 the willingness of members of the public to let (ex-)psychiatric patients participate in their private and/or family life has increased only very slightly.

CONCLUSION

Nowadays, just as in past decades, most Dutch citizens are not opposed to living alongside (discharged) psychiatric patients, but they have reservations about letting such persons participate in their private and family life.

An examination of generalized anxiety disorder and dysthymic disorder by latent class analysis

BACKGROUND

The nosological status of generalized anxiety disorder (GAD) versus dysthymic disorder (DD) has been questioned. The aim of this study was to examine qualitative differences within (co-morbid) GAD and DD symptomatology.

METHOD

Latent class analysis was applied to anxious and depressive symptomatology of respondents from three population-based studies (2007 Australian National Survey of Mental Health and Wellbeing; National Comorbidity Survey Replication; and Netherlands Mental Health Survey and Incidence Study-2; together known as the Triple study) and respondents from a multi-site naturalistic cohort [Netherlands Study of Depression and Anxiety (NESDA)]. Sociodemographics and clinical characteristics of each class were examined.

RESULTS

A three-class (Triple study) and two-class (NESDA) model best fitted the data, reflecting mainly different levels of severity of symptoms. In the Triple study, no division into a predominantly GAD or DD co-morbidity subtype emerged. Likewise, in spite of the presence of pure GAD and DD cases in the NESDA sample, latent class analysis did not identify specific anxiety or depressive profiles in the NESDA study. Next, sociodemographics and clinical characteristics of each class were examined. Classes only differed in levels of severity.

CONCLUSIONS

The absence of qualitative differences in anxious or depressive symptomatology in empirically derived classes questions the differentiation between GAD and DD.

The association between common mental disorders and violence: to what extent is it influenced by prior victimization, negative life events and low levels of social support?

BACKGROUND

Few studies have been published on the association between mental disorders and violence based on general population studies. Here we focus on different types of violence, adjusting for violent victimization and taking account of the limitations of previous population studies.

METHOD

Data were used from the first two waves of the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2), a nationally representative face-to-face survey of the general population aged 18-64 years (n = 6646). Violence was differentiated into physical and psychological violence against intimate partner(s), children or any person(s) in general. DSM-IV diagnoses were assessed with the Composite International Diagnostic Interview Version 3.0 (CIDI 3.0).

RESULTS

Psychological violence occurs considerably more frequently than physical violence, but both showed almost identical associations with mental disorders. After adjustment for sociodemographic characteristics, most of the main categories of common mental disorders were associated with violence. The strongest associations were found for externalizing disorders (substance use, impulse-control, antisocial personality disorder). After additional adjustment for violent victimization, negative life events and social support, most diagnostic correlates lost their significance whereas substance use (in particular alcohol) disorders were still associated with most types of violence.

CONCLUSIONS

The increased risk of violent offending among people with common mental disorders, other than substance use disorders, can be attributed to factors other than their mental illness.

[Prevalence, persistency and consequences of ADHD in the Dutch adult population]

BACKGROUND

Little is known about the prevalence and the consequences of attention-deficit hyperactivity disorder (ADHD) among adults in the general Dutch population.

AIM

To ascertain the prevalence of ADHD in childhood and adulthood, to investigate characteristics associated with the prevalence and persistency of ADHD and to draw a number of comparisons: to compare the functioning of adults with ADHD with that of people with a different mental disorder and to compare the extent to which these groups make use of treatment facilities.

METHOD

Data were derived from the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2), in which the occurrence of ADHD was determined in a representative sample of the Dutch population (n = 3,309; aged 18-44).

RESULTS

2.9% of the respondents had had ADHD in childhood, 70.0% of them still had the disorder in adulthood. An anxiety disorder before the age of 16 increased the risk of ADHD persistency, whereas an impulse-control disorder decreased this risk. ADHD in adulthood was associated with lower socio-economic status, mental disorders, poor functioning and increased use of treatment facilities. ADHD adults and adults with an anxiety or substance use disorder showed very similar functional limitations and used treatment facilities to approximately the same extent.

CONCLUSION

More than two-thirds of the adults who had had childhood ADHD still had the disorder in adulthood. The consequences of this in terms of functioning and use of treatment facilities are substantial.

Common mental disorder severity and its association with treatment contact and treatment intensity for mental health problems

BACKGROUND

Detailed population-based survey information on the relationship between the severity of common mental disorders (CMDs) and treatment for mental health problems is heavily based on North American research. The aim of this study was to replicate and expand existing knowledge by studying CMD severity and its association with treatment contact and treatment intensity in The Netherlands.

METHOD

Data were obtained from the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2), a nationally representative face-to-face survey of the general population aged 18–64 years (n=6646, response rate=65.1%). DSM-IV diagnoses and disorder severity were assessed with the Composite International Diagnostic Interview Version 3.0 (CIDI 3.0). Treatment contact refers to at least one contact for mental health problems made in the general medical care (GMC) or mental health care (MHC) sector. Four levels of treatment intensity were assessed, based on type and duration of therapy received.

RESULTS

Although CMD severity was related to treatment contact, only 39.0% of severe cases received MHC. At the same time, 40.3% of MHC users did not have a 12-month disorder. Increasing levels of treatment intensity ranged from 51.6% to 13.0% in GMC and from 81.4% to 51.1% in MHC. CMD severity was related to treatment intensity in MHC but not in GMC. Sociodemographic characteristics were not significantly related to having experienced the highest level of treatment intensity in MHC. CONCLUSIONS. Mental health treatment in the GMC sector should be improved, especially when policy is aimed at increasing the role of primary care in the management of mental health problems.

Testing the hypothesis that psychotic illness begins when subthreshold hallucinations combine with delusional ideation

OBJECTIVE

While hallucinations and delusions are often considered as a single class of 'positive symptoms', little is known about their dynamic cooccurrence in relation to clinical outcome in non-help-seeking people.

METHOD

The Netherlands Mental Health and Incidence Study (NEMESIS-1) is a longitudinal study of mental disorders (n = 7075) with three measurements over a 3-year period. Risk factors, persistence of psychotic experiences, and clinical outcome were analyzed for groups with: i) no psychotic experiences, ii) only delusions, iii) only hallucinations, and iv) both delusions and hallucinations.

RESULTS

Hallucinations and delusions occurred together more often (T0, 3.5%; T1, 1.0%; T2, 0.9%) than that predicted by chance (T0, 1.0%; T1, 0.1%; T2, 0.04%). The group with both symptoms showed more 'first-rank'-like delusions compared with the group with only delusions. Having both hallucinations and delusions, compared to isolated symptoms, was associated more strongly with risk factors, comorbid affective symptoms, negative symptoms, and persistence of psychotic experiences. This was not an artifact of having more symptoms in general.

CONCLUSION

Experiencing both delusions and hallucinations is an indicator of greater etiological load resulting in more clinical outcome. A specific 'hallucinatory-delusional state' may represent an early phase of exacerbation of aberrant attribution of salience, increasing risk for clinical outcome.

[Prevalence of mental disorders, and trends from 1996 to 2009. Results from NEMESIS-2]

BACKGROUND

Little is known about the prevalence and trends of mental disorders in the Dutch population.

AIM

To present the prevalences of lifetime and 12-month DSM-IV mood disorders, anxiety disorders, and substance use disorders and impulse-control disorders reported in NEMESIS-2 (Netherlands Mental Health Survey and Incidence Study), and to compare the 12-month prevalence of mood disorders, anxiety disorders and substance use disorders with estimates from the first study (NEMESIS-1).

METHOD

Between November 2007 and July 2009, face-to-face interviews were conducted among 6646 subjects aged 18-64 by means of the Composite International Diagnostic Interview 3.0. Trends in mental disorders were examined with these data and NEMESIS-1 data from 1996 (n = 7076).

RESULTS

The lifetime prevalence in NEMESIS-2 was 20.2% for mood disorder, 19.6% for anxiety disorder, 19.1% for substance use disorder and 9.2% for impulse-control or behaviour disorder. For the 12-month disorders, the prevalences were 6.1%, 10.1%, 5.6% and 2.1%, respectively. Between 1996 and 2007-2009, there was no change in the 12-month prevalence of anxiety disorder and substance use disorder. The 12-month prevalence of mood disorder decreased slightly but was no longer significant after differences in the sociodemographic variables between the two studies had been taken into account.

CONCLUSION

This study shows that in the Netherlands mental disorders occur fairly frequently. Over about a decade, no clear change was found in the mental health status of the population.

[Positive life events and mood disorders: longitudinal evidence for a chaotic life-course hypothesis]

BACKGROUND

In psychiatric research it is often assumed that detrimental effects of negative life events on mental health can be buffered by a number of positive life events. However, there is no convincing empirical evidence that this assumption is correct; it can even be argued that positive life events act as additional stressors rather than as buffers, leading to a continuation of a chaotic life course and an increase in the risk of affective disorders.

AIM

To find out whether positive life events were associated with a higher risk of the occurrence of mood disorders and whether such an association could be explained by a number of negative life events that individuals had experienced.

METHOD

We used data from 4,796 adults, aged 18-64, collected at two measurement moments (i.e. 1997 and 1999) of NEMESIS, a Dutch prospective-epidemiological study. As a basis for our measurements we used dsm-iii-r diagnoses of major depressive disorders and dysthymia and the Life Events and Difficulties Schedules LEDS.

RESULTS

A multivariate (MPlus) path analysis demonstrated that positive life events were not, in themselves, significantly predictive of affective disorders. Positive life events were only related to the risk of mood disorders when they co-occurred with a high number of negative life events.

CONCLUSIONS

In accordance with a chaotic life-course hypothesis, positive events were not found to buffer the detrimental impact of negative life events, but when they are part of an erratic course of life they can pose an extra threat to an individual’s mental health.

Berkson's bias and the mood dimensions of bipolar disorder

In this paper we examined whether manic and depressive dimensions independently contribute to mental health service use and determined the degree of comorbidity between manic and depressive dimensions in individuals with and without mental health service use. If both depressive and manic episodes independently influence help-seeking behaviour, a higher level of comorbidity between these dimensions would be found in clinical as compared to non-clinical samples (i.e. Berkson's Bias). Data were derived from the Netherlands Mental Health Survey and Incidence Study (NEMESIS), a prospective epidemiological survey in a representative sample of the Dutch population (N = 7076). Dimensions of depression and mania and mental health service use (MHSU) were assessed with the Composite International Diagnostic Interview (CIDI) at baseline, and prospectively one and three years later. Logistic regression was used to test whether depressive and manic dimensions both had independent effects on mental health service use. The degree of mania-comorbidity given the presence of depressive dimension was assessed as a function of MHSU, both retrospectively and prospectively. Manic and depressive dimensions contributed independently to mental health service use. Mania-comorbidity given the presence of depressive dimension was significantly higher in individuals with mental health service use than in those without, both retrospectively (16.7% versus 7.1%, p = 0.000) and prospectively (10.8% versus 6.6%, p = 0.017). We conclude that the bipolar phenotype consists of manic and depressive dimensions that may be much more loosely associated than (Berkson) biased clinical observations suggest. A dimension-specific approach may be more productive in clarifying the aetiology of mood dysregulation.

Social phobia and number of social fears, and their association with comorbidity, health-related quality of life and help seeking: a population-based study

OBJECTIVES

Community based data were used to examine the association between social phobia and comorbidity, quality of life and service utilization. In addition, the correlations of the number of social fears with these domains were studied.

METHOD

Data are from the Netherlands Mental Health Survey and Incidence Study (NEMESIS) (N = 7,076). Social phobia was assessed according to DSM-III-R with the Composite International Diagnostic Interview (CIDI); quality of life was assessed according to the Short-Form-36 Health Survey (SF-36).

RESULTS

The 12-month prevalence of social phobia was 4.8%. Being female, young, low educated, a single parent, living alone, not having a paid job and having a somatic disorder are associated with 12-month social phobia. Mean and median ages of onset of social phobia were 19.1 and 16.0 years, respectively, and mean and median duration were 16.8 and 14.0 years, respectively. 66% of respondents with social phobia had at least one comorbid condition. 12-month social phobia was significantly related to lower quality of life and higher service utilization. The mean number of feared social situations was 2.73 out of the 6 assessed. As the number of social fears increases, comorbidity and service utilization increases, and the quality of life decreases.

CONCLUSIONS

These findings suggest as the number of feared social situations increases, the burden of social phobia rises. In other words, like comorbidity or decreased quality of life, the number of social fears is also an important indicator of the severity of social phobia. We conclude that from a public health perspective, mental health care givers should pay attention to the number of social fears in order to check the severity of social phobia.

Work and family roles and the association with depressive and anxiety disorders: differences between men and women

BACKGROUND

This study examined the associations of (combinations of) social roles (employee, partner and parent) with the prevalence of anxiety and depressive disorders and whether social roles contribute to the explanation of the female preponderance in these disorders.

METHOD

This was a cross-sectional study using data from 3857 respondents aged 25-55 of NEMESIS (Netherlands Mental Health Survey and Incidence Study). Depression and anxiety disorders were measured using the CIDI 1.1.

RESULTS

The OR of depressive disorders and anxiety disorders among women compared to men was 1.71 (95% CI: 1.40-2.10). Among both genders, the partner role was associated with decreased risks of depression and anxiety and the parent role was not. The work role was a significant protective factor of depression and anxiety for men (OR=0.40; 95% CI: 0.24-0.69) but not for women (OR=0.86; 95% CI: 0.66-1.12). The effect of the work role was positive among women without children (OR=0.28; 95% CI: 0.14-0.54), but not among those with children (OR=1.01; 95% CI: 0.75-1.35). The gender risk for depression and anxiety decreased significantly by adding the work role variables into the model.

LIMITATIONS

This was a cross-sectional study. This study did not give insight into the quality of social roles.

CONCLUSION

The work role contributed to the explanation of the female preponderance in depression and anxiety disorders. Considering depression and anxiety among women, a focus upon quality and meaning of the work role, and barriers in combining the work role and parent role may be essential.

Economic costs of minor depression: a population-based study

OBJECTIVE

Although the clinical relevance of minor depression has been demonstrated in many studies, the economic costs are not well explored. In this study, we examine the economic costs of minor depression.

METHOD

In a large-scale, population-based study in the Netherlands (n = 5504) the costs of minor depression were compared with the costs of major depression and dysthymia. Excess costs, i.e. the costs of a disorder over and above the costs attributable to other illnesses, were estimated with help of regression analysis. The direct medical costs, the direct non-medical costs and the indirect non-medical costs were calculated. The year 2003 was used as the reference year.

RESULTS

The annual per capita excess costs of minor depression were US$ 2141 (95% CI = 753-3529) higher than the base rate costs of US$ 1023, while the costs of major depression were US$ 3313 (95% CI = 1234-5390) higher than the base rate. The costs of minor depression per 1 million inhabitants were 160 million dollars per year, which is somewhat less than the costs of major depression (192 million dollars per year).

CONCLUSION

The economic costs associated with minor depression are considerable and approach those of major depression.

Plastid transformants of tomato selected using mutations affecting ribosome structure

Tomato plastid transformants were obtained using two vectors containing cloned plastid DNA of either Nicotiana tabacum or Solanum nigrum and including point mutations conferring resistance to spectinomycin and streptomycin. Transformants were recovered after PEG-mediated direct DNA uptake into protoplasts, followed by selection on spectinomycin-containing medium. Sixteen lines contained the point mutation, as confirmed by mapping restriction enzyme sites. One line obtained with each vector was analysed in more detail, in comparison with a spontaneous spectinomycin-resistant mutant. Integration of the cloned Solanum or Nicotiana plastid DNA, by multiple recombination events, into the tomato plastome was confirmed by sequence analysis of the targeted region of plastid DNA in the inverted repeat region. Maternal inheritance of spectinomycin and streptomycin resistances or sensitivity in seedlings also confirmed the transplastomic status of the two transformants. The results demonstrate the efficacy in tomato of a selection strategy which avoids the integration of a dominant bacterial antibiotic resistance gene.