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Purpose The health correlates of polygenic risk (PRS-SCZ) and exposome (ES-SCZ) scores for schizophrenia may vary depending on age and sex. We aimed to examine age- and sex-specific associations of PRS-SCZ and ES-SCZ with self-reported health in the general population. Methods Participants were from the population-based Netherlands Mental Health Survey and Incidence Study–2 (NEMESIS-2). Mental and physical health were measured with the 36-item Short Form Survey 4 times between 2007 and 2018. The PRS-SCZ and ES-SCZ were respectively calculated from common genetic variants and exposures (cannabis use, winter birth, hearing impairment, and five childhood adversity categories). Moderation by age and sex was examined in linear mixed models. Results For PRS-SCZ and ES-SCZ analyses, we included 3099 and 6264 participants, respectively (age range 18–65 years; 55.7–56.1% female). Age and sex did not interact with PRS-SCZ. Age moderated the association between ES-SCZ and mental (interaction: p = 0.02) and physical health (p = 0.0007): at age 18, + 1.00 of ES-SCZ was associated with − 0.10 of mental health and − 0.08 of physical health, whereas at age 65, it was associated with − 0.21 and − 0.23, respectively (all units in standard deviations). Sex moderated the association between ES-SCZ and physical health (p Conclusion There were larger associations between higher ES-SCZ and poorer health among female and older individuals. Accounting for these interactions may increase ES-SCZ precision and help uncover populational determinants of environmental influences on health.

Borderline personality disorder (BPD) has a negative impact on the onset and course of anxiety disorders. However, even though many people with anxiety disorders only have some BPD symptoms, little is known about the impact of BPD symptoms on anxiety disorders. This study examines the impact of BPD symptoms on the onset and persistence of anxiety disorders over a 3-year follow-up in the general population. Longitudinal data from the Netherlands Mental Health Survey and Incidence study were used (N = 4,618). BPD symptoms were assessed using the International Personality Examination, and anxiety disorders and other mental disorders were assessed with the Composite International Diagnostic Interview. Logistic regression analyses were performed, adjusting for a wide range of potential confounders such as childhood abuse and mood disorders. In all, 72.1% of the participants reported no BPD symptoms, 24.0% reported one to two symptoms, 3.1% reported three to four symptoms, and 0.8% reported ≥ 5 symptoms. There was a clear dose-response relation, with more BPD symptoms being associated with a higher risk for onset and persistence of anxiety disorders (both p for trend < .001). Even one to two BPD symptoms significantly impacted the onset (odds ratio = 3.32, 95% confidence interval [1.68, 6.54]) and persistence (odds ratio = 3.12, 95% confidence interval [1.01, 9.64]). Results appeared to be independent of multiple potential confounders. Even a low number of BPD symptoms impact the onset and persistence of anxiety disorders. Targeting these symptoms may improve the outcome of anxiety disorders. Future research should study the effect of various interventions for people with anxiety disorders and BPD symptoms. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Aims There are indications that problematic alcohol use may negatively impact the course of major depressive disorder (MDD). However, most studies on alcohol use and adverse MDD outcomes are conducted amongst MDD populations with (severe) alcohol use disorder in psychiatric treatment settings. Therefore, it remains unclear whether these results can be generalised to the general population. In light of this, we examined the longitudinal relationship between alcohol use and MDD persistence after a 3-year follow-up amongst people with MDD from the general population. Methods Data were derived from the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2), a psychiatric epidemiological prospective study comprising four waves amongst the adult Dutch general population (n = 6.646). The study sample (n = 642) consisted of those with 12-month MDD who participated at the follow-up wave. The outcome was 12-month MDD persistence after the 3-year follow-up, which was assessed via the Composite International Diagnostic Interview version 3.0. Weekly alcohol consumption was operationalised as non-drinking (0 drinks), low-risk drinking (⩽7 drinks; reference), at-risk drinking (women 8–13 drinks, men 8–20 drinks) and high-risk drinking (women ⩾14, men ⩾21 drinks). We performed univariate and multiple logistic regression analyses, which were adjusted for various socio-demographic and health-related factors. Results The majority (67.4%) of the MDD sample were female, while the mean age was 47.1 years. Amongst these, 23.8% were non-drinkers, 52.0% were low-risk drinkers and 14.3% and 9.4% were at-risk and high-risk drinkers, respectively. Around one-quarter of the sample (23.6%) met the criteria for a persistent MDD after 3-year follow-up. No statistically significant association was found between alcohol use and MDD persistence, either for the crude model or the adjusted models. In comparison to low-risk drinking, the full adjusted model showed no statistically significant associations between MDD persistence and non-drinking (odds ratio (OR) = 1.15, p = 0.620), at-risk drinking (OR = 1.25, p = 0.423), or high-risk drinking (OR = 0.74, p = 0.501). Conclusions Contrary to our expectations, our findings showed that alcohol use was not a predictor of MDD persistence after 3-year follow-up amongst people with MDD from the general population.

Researchers and politicians have regularly expressed their worries about a widening of socioeconomic inequalities in physical and mental health. Debts have been relatively understudied as a specific aspect of socioeconomic disadvantage contributing to poor mental health. This study examines the bidirectional association between debts and common mental disorders (CMDs) in the adult population of the Netherlands. Data were obtained from the second (‘baseline’) and third (3-year follow-up) wave of the Netherlands Mental Health Survey and Incidence Study-2, a representative cohort of adults. Questions were asked about debts and difficulty in repaying debts in the past 12 months. The answers were combined into one variable: no debts, easy, difficult, and very difficult to pay back debts. Twelve-month CMDs were assessed with the Composite International Diagnostic Interview version 3.0. Increasing levels of difficulty in repaying debts predicted onset of CMD at follow-up in those without 12-month CMD at baseline, and persistence of CMD at follow-up in those with 12-month CMD at baseline. Conversely, CMD was not linked to onset of debts at follow-up in those without 12-month debts at baseline, but was associated with persistence of difficulty to pay back debts at follow-up in those with 12-month debts at baseline. These associations remained significant after adjustment for baseline sociodemographic variables, negative life events and physical health. Health professionals and debt counsellors should pay more attention to patients’ debts and clients’ mental health respectively in order to refer those with financial or mental health problems to the appropriate services. Supplementary Information The online version contains supplementary material available at 10.1007/s10488-021-01131-9.

BackgroundA transdiagnostic and contextual framework of ‘clinical characterization’, combining clinical, psychopathological, sociodemographic, etiological, and other personal contextual data, may add clinical value over and above categorical algorithm-based diagnosis.MethodsPrediction of need for care and health care outcomes was examined prospectively as a function of the contextual clinical characterization diagnostic framework in a prospective general population cohort (n = 6646 at baseline), interviewed four times between 2007 and 2018 (NEMESIS-2). Measures of need, service use, and use of medication were predicted as a function of any of 13 DSM-IV diagnoses, both separately and in combination with clinical characterization across multiple domains: social circumstances/demographics, symptom dimensions, physical health, clinical/etiological factors, staging, and polygenic risk scores (PRS). Effect sizes were expressed as population attributable fractions.ResultsAny prediction of DSM-diagnosis in relation to need and outcome in separate models was entirely reducible to components of contextual clinical characterization in joint models, particularly the component of transdiagnostic symptom dimensions (a simple score of the number of anxiety, depression, mania, and psychosis symptoms) and staging (subthreshold, incidence, persistence), and to a lesser degree clinical factors (early adversity, family history, suicidality, slowness at interview, neuroticism, and extraversion), and sociodemographic factors. Clinical characterization components in combination predicted more than any component in isolation. PRS did not meaningfully contribute to any clinical characterization model.ConclusionA transdiagnostic framework of contextual clinical characterization is of more value to patients than a categorical system of algorithmic ordering of psychopathology.

Background Psychotic experiences (PEs) frequently occur and are associated with a range of negative health outcomes. Prospective studies on PEs are scarce, and to date no study investigated PE prevalence, incidence, persistence, their risk indicators, and psychiatric comorbidity, in one dataset. Furthermore, most studies are based on self-report, and it is unclear how this compares to clinical interviews. Methods Data are used from the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2), a psychiatric cohort study among a representative sample of adults (baseline characteristics: N = 6646; 49.6% female; 18–64 years). Results are presented for self-reported and clinically validated PEs. Associations are assessed for mental disorders, socio-demographic, vulnerability, physical health, and substance use factors. Results Based on self-report, at baseline 16.5% of respondents had at least one PE in their lifetime, of those, 30.1% also reported a PE at 3-year follow-up. 4.8% had a first PE at 3-year follow up. The 3-year prevalence of PE was associated with almost all studied risk indicators. Generally, the strongest associations were found for mental health disorders. Prevalence and incidence rates were two to three times higher in self-report than in clinical interview but results on associated factors were similar. Conclusions Validated prevalence and incidence estimates of PE are substantially lower than self-reported figures but results on associated factors were similar. Therefore, future studies on associations of PEs can rely on relatively inexpensive self-reports of PEs. The associations between PE and mental disorders underline the importance of assessment of PE in general practice.

Background Empirical evidence suggests that people use cannabis to ameliorate anxiety and depressive symptoms, yet cannabis also acutely worsens psychosis and affective symptoms. However, the temporal relationship between cannabis use, anxiety and depressive symptoms and psychotic experiences (PE) in longitudinal studies is unclear. This may be informed by examination of mutually mediating roles of cannabis, anxiety and depressive symptoms in the emergence of PE. Methods Data were derived from the second longitudinal Netherlands Mental Health Survey and Incidence Study. Mediation analysis was performed to examine the relationship between cannabis use, anxiety/depressive symptoms and PE, using KHB logit in STATA while adjusting for age, sex and education status. Results Cannabis use was found to mediate the relationship between preceding anxiety, depressive symptoms and later PE incidence, but the indirect contribution of cannabis use was small (for anxiety: % of total effect attributable to cannabis use = 1.00%; for depression: % of total effect attributable to cannabis use = 1.4%). Interestingly, anxiety and depressive symptoms were found to mediate the relationship between preceding cannabis use and later PE incidence to a greater degree (% of total effect attributable to anxiety = 17%; % of total effect attributable to depression = 37%). Conclusion This first longitudinal cohort study examining the mediational relationship between cannabis use, anxiety/depressive symptoms and PE, shows that there is a bidirectional relationship between cannabis use, anxiety/depressive symptoms and PE. However, the contribution of anxiety/depressive symptoms as a mediator was greater than that of cannabis.

NEMESIS-3 (Netherlands Mental Health Survey and Incidence Study-3) is a psychiatric epidemiological cohort study of the Dutch general population that replicates and expands on two previous NEMESIS-studies conducted in 1996-1999 and 2007-2018 respectively. The main aims of NEMESIS-3 are to provide up-to-date information on the prevalence, incidence, course and consequences of mental disorders, their risk indicators, and to study the relevant time trends. This paper gives an overview of the objectives and methods of NEMESIS-3, especially of the recently completed first wave, and describes the sample characteristics.NEMESIS-3 is based on a multistage, stratified random sampling of individuals aged 18-75 years. Face-to-face interviews were laptop computer-assisted and held at the respondent's home. A slightly modified Composite International Diagnostic Interview (CIDI) version 3.0 was used to assess both Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) and DSM-5 mental disorders. Two follow-up waves are planned three and six years after baseline.In the first wave, performed from November 2019 to March 2022, 6194 individuals were interviewed: 1576 respondents before and 4618 respondents during the COVID-19 pandemic. The average interview duration was 91 min and the response rate was 54.6%. The sample consisted of 50.4% women and had a mean age of 47.9 years. The sample was reasonable nationally representative, although some sociodemographic groups were somewhat underrepresented.Despite the COVID-19 restrictions, we were able to build a large and comprehensive dataset of good quality, permitting us to investigate the latest trends in mental health status, various new topics related to mental health, and the extent to which the pandemic has had an effect on the population's mental health.

Sexual minority individuals are more likely to have mental disorders, including mood, anxiety, and substance use disorders, compared to heterosexual individuals. Whether experiencing trauma or bullying-victimization during childhood explains these differences is currently unclear. We used a psychiatric epidemiological general population-based study to assess whether childhood trauma severity and bullying-victimization before age 16 explains the difference by sexual attraction in mental disorders. Data from the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2; N = 6392) were used to examine (1) whether same/both-sex attraction and predominantly other-sex attraction is linked to self-reports of childhood trauma (types and severity) and bullying-victimization, and (2) whether these experiences explain differences between these groups in lifetime and 12-month prevalence of DSM-IV disorders assessed by the Composite International Diagnostic Interview 3.0. Same/both-sex attracted individuals reported a higher childhood trauma severity score compared to exclusively other-sex attracted individuals (B = 0.93, SE = 0.20, p < .001), and were more likely to report bullying-victimization (OR = 2.51 95%CI[1.68, 3.74]). DSM-IV disorders were more prevalent among same/both-sex attracted individuals than among exclusively other-sex attracted individuals (ORs ranged from 1.57 to 4.68). There were no differences in DSM-IV disorders for predominantly other-sex attracted individuals. Childhood trauma severity explained between 9.0% and 57.0% of significant indirect associations between same/both-sex attraction and DSM-IV disorders. Sexual minority individuals experience more types of, and more severe childhood trauma, and are more likely to experience bullying-victimization. These negative experiences partly explained disparities in mental disorders.

There is consistent evidence from cross-sectional studies that smoking is positively associated with mental disorders. The research on the prospective association, however, is inconsistent. In the present study, we aimed to further increase the knowledge of this association by addressing several issues in the body of research. Data used were from a nationally representative, population-based cohort study among 18- to 64-year-olds at baseline. Compared with nonsmokers, smokers at baseline were significantly more likely to experience first incidence of any mood, anxiety, or substance use disorder at 3-year follow-up while controlling for a wide range of confounding factors. The association with incident mood and anxiety disorders was particularly high among heavy smokers. The dose-effect analyses on later substance use disorders showed unclear results, warranting further research. Additional analyses showed that results at 6-year follow-up were very similar, except for a weaker relationship between smoking and substance use disorders.

Previously, we established an estimated exposome score for schizophrenia (ES-SCZ) as a cumulative measure of environmental liability for schizophrenia to use in gene–environment interaction studies and for risk stratification in population cohorts. Hereby, we examined the discriminative function of ES-SCZ for identifying individuals diagnosed with schizophrenia spectrum disorder in the general population by measuring the area under the receiver operating characteristic curve (AUC). Furthermore, we compared this ES-SCZ method to an environmental sum score (Esum-SCZ) and an aggregate environmental score weighted by the meta-analytical estimates (Emet-SCZ). We also estimated ORs and Nagelkerke’s R2 for ES-SCZ in association with psychiatric diagnoses and other medical outcomes. ES-SCZ showed a good discriminative function (AUC = 0.84) and statistically significantly performed better than both Esum-SCZ (AUC = 0.80) and Emet-SCZ (AUC = 0.80). At optimal cut point, ES-SCZ showed similar performance in ruling out (LR− = 0.20) and ruling in (LR+ = 3.86) schizophrenia. ES-SCZ at optimal cut point showed also a progressively greater magnitude of association with increasing psychosis risk strata. Among all clinical outcomes, ES-SCZ was associated with schizophrenia diagnosis with the highest OR (2.76, P < .001) and greatest explained variance (R2 = 14.03%), followed by bipolar disorder (OR = 2.61, P < .001, R2 = 13.01%) and suicide plan (OR = 2.44, P < .001, R2 = 12.44%). Our findings from an epidemiologically representative general population cohort demonstrate that an aggregate environmental exposure score for schizophrenia constructed using a predictive modeling approach—ES-SCZ—has the potential to improve risk prediction and stratification for research purposes and may help gain insight into the multicausal etiology of psychopathology.

This cohort study assesses whether recent stressful life events interact with genetic and environmental liability for schizophrenia in models of mental and physical health in the Dutch adult population.Key PointsQuestionIs the association of adulthood life stress with mental and physical health moderated by polygenic risk and exposome scores for schizophrenia? FindingsThis population-based cohort study of 6646 participants provides novel evidence of the associations of genetic and environmental liability for schizophrenia with mental health in the general population. Both genetic and environmental liability were associated with poor outcomes, particularly mental health, and the association between stressful life events and health outcomes was moderated by exposome score but not polygenic risk score for schizophrenia. MeaningThese findings showing an interaction between adulthood stressful life events and lifetime exposomic liability lend further support to the diathesis-stress model.ImportanceBoth adulthood stressful life events (SLEs) and liability for schizophrenia have been associated with poor mental and physical health in the general population, but their interaction remains to be elucidated to improve population-based health outcomes. ObjectiveTo test whether recent SLEs interact with genetic and environmental liability for schizophrenia in models of mental and physical health. Design, Setting, and ParticipantsThe Netherlands Mental Health Survey and Incidence Study-2 is a population-based prospective cohort study designed to investigate the prevalence, incidence, course, and consequences of mental disorders in the Dutch general population. Participants were enrolled from November 5, 2007, to July 31, 2009, and followed up with 3 assessments during 9 years. Follow-up was completed on June 19, 2018, and data were analyzed from September 1 to November 1, 2019. ExposuresRecent SLEs assessed at each wave and aggregate scores of genetic and environmental liability for schizophrenia: polygenic risk score for schizophrenia (PRS-SCZ) trained using the Psychiatric Genomics Consortium analysis results and exposome score for schizophrenia (ES-SCZ) trained using an independent data set. Main Outcomes and MeasuresIndependent and interacting associations of SLEs with ES-SCZ and PRS-SCZ on mental and physical health assessed at each wave using regression coefficients. ResultsOf the 6646 participants included at baseline, the mean (SD) age was 44.26 (12.54) years, and 3672 (55.25%) were female. The SLEs were associated with poorer physical health (B=-3.22 [95% CI, -3.66 to -2.79]) and mental health (B=-3.68 [95% CI, -4.05 to -3.32]). Genetic and environmental liability for schizophrenia was associated with poorer mental health (ES-SCZ: B=-3.07 [95% CI, -3.35 to -2.79]; PRS-SCZ: B=-0.93 [95% CI, -1.31 to -0.54]). Environmental liability was also associated with poorer physical health (B=-3.19 [95% CI, -3.56 to -2.82]). The interaction model showed that ES-SCZ moderated the association of SLEs with mental (B=-1.08 [95% CI, -1.47 to -0.69]) and physical health (B=-0.64 [95% CI, -1.11 to -0.17]), whereas PRS-SCZ did not. Several sensitivity analyses confirmed these results. Conclusions and RelevanceIn this study, schizophrenia liability was associated with broad mental health outcomes at the population level. Consistent with the diathesis-stress model, exposure to SLEs, particularly in individuals with high environmental liability for schizophrenia, was associated with poorer health. These findings underline the importance of modifiable environmental factors during the life span for population-based mental health outcomes.

BackgroundThere is evidence that environmental and genetic risk factors for schizophrenia spectrum disorders are transdiagnostic and mediated in part through a generic pathway of affective dysregulation.MethodsWe analysed to what degree the impact of schizophrenia polygenic risk (PRS-SZ) and childhood adversity (CA) on psychosis outcomes was contingent on co-presence of affective dysregulation, defined as significant depressive symptoms, in (i) NEMESIS-2 (n = 6646), a representative general population sample, interviewed four times over nine years and (ii) EUGEI (n = 4068) a sample of patients with schizophrenia spectrum disorder, the siblings of these patients and controls.ResultsThe impact of PRS-SZ on psychosis showed significant dependence on co-presence of affective dysregulation in NEMESIS-2 [relative excess risk due to interaction (RERI): 1.01, p = 0.037] and in EUGEI (RERI = 3.39, p = 0.048). This was particularly evident for delusional ideation (NEMESIS-2: RERI = 1.74, p = 0.003; EUGEI: RERI = 4.16, p = 0.019) and not for hallucinatory experiences (NEMESIS-2: RERI = 0.65, p = 0.284; EUGEI: −0.37, p = 0.547). A similar and stronger pattern of results was evident for CA (RERI delusions and hallucinations: NEMESIS-2: 3.02, p < 0.001; EUGEI: 6.44, p < 0.001; RERI delusional ideation: NEMESIS-2: 3.79, p < 0.001; EUGEI: 5.43, p = 0.001; RERI hallucinatory experiences: NEMESIS-2: 2.46, p < 0.001; EUGEI: 0.54, p = 0.465).ConclusionsThe results, and internal replication, suggest that the effects of known genetic and non-genetic risk factors for psychosis are mediated in part through an affective pathway, from which early states of delusional meaning may arise.

The polygenic risk score (PRS) allows for quantification of the relative contributions of genes and environment in population-based studies of mental health. We analyzed the impact of transdiagnostic schizophrenia PRS and measures of familial and environmental risk on the level of and change in general mental health (Short-Form-36 mental health) in the Netherlands Mental Health Survey and Incidence Study-2 general population sample, interviewed 4 times over a period of 9 years, yielding 8901 observations in 2380 individuals. Schizophrenia PRS, family history, somatic pain, and a range of environmental risks and social circumstances were included in the regression model of level of and change in mental health. We calculated the relative contribution of each (group of) risk factor(s) to the variance in (change in) mental health. In the combined model, familial and environmental factors explained around 17% of the variance in mental health, of which around 5% was explained by age and sex, 30% by social circumstances, 16% by pain, 22% by environmental risk factors, 24% by family history, and 3% by PRS for schizophrenia (PRS-SZ). Results were similar, but attenuated, for the model of mental health change over time. Childhood trauma and gap between actual and desired social status explained most of the variance. PRS for bipolar disorder, cross-disorder, and depression explained less variance in mental health than PRS-SZ. Polygenic risk for mental suffering, derived from significance-testing in massive samples, lacks impact in analyses focusing on prediction in a general population epidemiological setting. Social-environmental circumstances, particularly childhood trauma and perceived status gap, drive most of the attributable variation in population mental health.

This study aims to disentangle the contribution of genetic liability, educational attainment (EA), and their overlap and interaction in lifetime smoking. We conducted genome-wide association studies (GWASs) in UK Biobank (N = 394,718) to (i) capture variants for lifetime smoking, (ii) variants for EA, and (iii) variants that contribute to lifetime smoking independently from EA (‘smoking-without-EA’). Based on the GWASs, three polygenic scores (PGSs) were created for individuals from the Netherlands Twin Register (NTR, N = 17,805) and the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2, N = 3090). We tested gene–environment (G × E) interactions between each PGS, neighborhood socioeconomic status (SES) and EA on lifetime smoking. To assess if the PGS effects were specific to smoking or had broader implications, we repeated the analyses with measures of mental health. After subtracting EA effects from the smoking GWAS, the SNP-based heritability decreased from 9.2 to 7.2%. The genetic correlation between smoking and SES characteristics was reduced, whereas overlap with smoking traits was less affected by subtracting EA. The PGSs for smoking, EA, and smoking-without-EA all predicted smoking. For mental health, only the PGS for EA was a reliable predictor. There were suggestions for G × E for some relationships, but there were no clear patterns per PGS type. This study showed that the genetic architecture of smoking has an EA component in addition to other, possibly more direct components. PGSs based on EA and smoking-without-EA had distinct predictive profiles. This study shows how disentangling different models of genetic liability and interplay can contribute to our understanding of the etiology of smoking.

Objective: Little is known about the course of anxiety disorders in the general population. This study provides insights into the course of anxiety disorders in the general population taking into account transition to residual symptoms and to other diagnostic categories. Methods: Using data from three waves of the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2; n = 6646), subjects with anxiety disorders (T0; n = 243) were divided into three mutually exclusive course trajectories according to their diagnostic status at 3-year (T1) and 6-year (T2) follow-up: remission group (no disorder at T2), intermittent course group (no disorder at T1 and disorder at T2) and chronic course group (disorder at all measurements). Transition to residual symptoms or other psychopathology were studied. In addition, predictors of course trajectories were assessed. Results: During 6-year follow-up, 77.8% of subjects achieved remission, 14.0% followed an intermittent course and 8.2% a chronic course. Of those in remission, residual anxiety symptoms remained in 46.6%, while 7.9% developed another disorder between T0 and T2. Compared with the remitting group, a chronic course was predicted by not living with a partner, multiple negative life events, neuroticism, lower mental functioning, severity of anxiety symptoms, use of mental health care and medication use. Limitations: The intermittent and chronic course groups were small, limiting statistical power. As a result, certain predictors may not have reached significance. Conclusions: In the general population at 6-year follow-up, 77.8% of subjects with anxiety disorders achieved remission. Because of transition to residual symptoms or another diagnostic category, only 52.4% of those subjects had a true favourable outcome.

BackgroundAnxiety disorders frequently recur in clinical populations, but the risk of recurrence of anxiety disorders is largely unknown in the general population. In this study, recurrence of anxiety and its predictors were studied in a large cohort of the adult general population.MethodsBaseline, 3-year and 6-year follow-up data were derived from the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2). Respondents (N = 468) who had been in remission for at least a year prior to baseline were included. Recurrence was assessed at 3 and 6 years after baseline, using the Composite International Diagnostic Interview version 3.0. Cumulative recurrence rates were estimated using the number of years since remission of the last anxiety disorder. Furthermore, Cox regression analyses were conducted to investigate predictors of recurrence, using a broad range of putative predictors.ResultsThe estimated cumulative recurrence rate was 2.1% at 1 year, 6.6% at 5 years, 10.6% at 10 years, and 16.2% at 20 years. Univariate regression analyses predicted a shorter time to recurrence for several variables, of which younger age at interview, parental psychopathology, neuroticism and a current depressive disorder remained significant in the, age and gender-adjusted, multivariable regression analysis.ConclusionsRecurrence of anxiety disorders in the general population is common and the risk of recurrence extends over a lengthy period of time. In clinical practice, alertness to recurrence, monitoring of symptoms, and quick access to health care in case of recurrence are needed.

Aims Although attenuated psychotic symptoms in the psychosis clinical high-risk state (CHR-P) almost always occur in the context of a non-psychotic disorder (NPD), NPD is considered an undesired ‘comorbidity’ epiphenomenon rather than an integral part of CHR-P itself. Prospective work, however, indicates that much more of the clinical psychosis incidence is attributable to prior mood and drug use disorders than to psychosis clinical high-risk states per se. In order to examine this conundrum, we analysed to what degree the ‘risk’ in CHR-P is indexed by co-present NPD rather than attenuated psychosis per se. Methods We examined the incidence of early psychotic experiences (PE) with and without NPD (mood disorders, anxiety disorders, alcohol/drug use disorders), in a prospective general population cohort (n = 6123 at risk of incident PE at baseline). Four interview waves were conducted between 2007 and 2018 (NEMESIS-2). The incidence of PE, alone (PE-only) or with NPD (PE + NPD) was calculated, as were differential associations with schizophrenia polygenic risk score (PRS-Sz), environmental, demographical, clinical and cognitive factors. Results The incidence of PE + NPD (0.37%) was lower than the incidence of PE-only (1.04%), representing around a third of the total yearly incidence of PE. Incident PE + NPD was, in comparison with PE-only, differentially characterised by poor functioning, environmental risks, PRS-Sz, positive family history, prescription of antipsychotic medication and (mental) health service use. Conclusions The risk in ‘clinical high risk’ states is mediated not by attenuated psychosis per se but specifically the combination of attenuated psychosis and NPD. CHR-P/APS research should be reconceptualised from a focus on attenuated psychotic symptoms with exclusion of non-psychotic DSM-disorders, as the ‘pure' representation of a supposedly homotypic psychosis risk state, towards a focus on poor-outcome NPDs, characterised by a degree of psychosis admixture, on the pathway to psychotic disorder outcomes.

Predicting the onset and persistence of psychopathology and limited functioning might enable personalized care. Specific phobia (SP) might serve as a predictor, but this needs further evaluation. Participants of the Netherlands Mental Health Survey and Incidence Study-2 were divided into three groups: no-SP (n = 6094), history of SP (n = 204), and current SP (n = 348). Results showed that current SP was associated with a higher prevalence of other anxiety disorders, mood and substance use disorders, and lower levels of functioning. The 6-year onset of other anxiety disorders was associated with history and current SP. Current-SP was also associated with the onset of mood disorders. Neuroticism and childhood trauma only partly accounted for these associations. To conclude, SP was independently associated with presence and onset of other disorders and with limited functioning over time. The presence of SP may serve as an identifier of persons vulnerable to the development of other psychopathologies.

BackgroundStudies on neighbourhood characteristics and depression show equivocal results.AimsThis large-scale pooled analysis examines whether urbanisation, socioeconomic, physical and social neighbourhood characteristics are associated with the prevalence and severity of depression.MethodCross-sectional design including data are from eight Dutch cohort studies (n= 32 487). Prevalence of depression, either DSM-IV diagnosis of depressive disorder or scoring for moderately severe depression on symptom scales, and continuous depression severity scores were analysed. Neighbourhood characteristics were linked using postal codes and included (a) urbanisation grade, (b) socioeconomic characteristics: socioeconomic status, home value, social security beneficiaries and non-Dutch ancestry, (c) physical characteristics: air pollution, traffic noise and availability of green space and water, and (d) social characteristics: social cohesion and safety. Multilevel regression analyses were adjusted for the individual's age, gender, educational level and income. Cohort-specific estimates were pooled using random-effects analysis.ResultsThe pooled analysis showed that higher urbanisation grade (odds ratio (OR) = 1.05, 95% CI 1.01–1.10), lower socioeconomic status (OR = 0.90, 95% CI 0.87–0.95), higher number of social security beneficiaries (OR = 1.12, 95% CI 1.06–1.19), higher percentage of non-Dutch residents (OR = 1.08, 95% CI 1.02–1.14), higher levels of air pollution (OR = 1.07, 95% CI 1.01–1.12), less green space (OR = 0.94, 95% CI 0.88–0.99) and less social safety (OR = 0.92, 95% CI 0.88–0.97) were associated with higher prevalence of depression. All four socioeconomic neighbourhood characteristics and social safety were also consistently associated with continuous depression severity scores.ConclusionsThis large-scale pooled analysis across eight Dutch cohort studies shows that urbanisation and various socioeconomic, physical and social neighbourhood characteristics are associated with depression, indicating that a wide range of environmental aspects may relate to poor mental health.Declaration of interestNone.

BackgroundEvidence suggests that cannabis use, childhood adversity, and urbanicity, in interaction with proxy measures of genetic risk, may facilitate onset of psychosis in the sense of early affective dysregulation becoming ‘complicated’ by, first, attenuated psychosis and, eventually, full-blown psychotic symptoms.MethodsData were derived from three waves of the second Netherlands Mental Health Survey and Incidence Study (NEMESIS-2). The impact of environmental risk factors (cannabis use, childhood adversity, and urbanicity) was analyzed across severity levels of psychopathology defined by the degree to which affective dysregulation was ‘complicated’ by low-grade psychotic experiences (‘attenuated psychosis’ – moderately severe) and, overt psychotic symptoms leading to help-seeking (‘clinical psychosis’ – most severe). Familial and non-familial strata were defined based on family history of (mostly) affective disorder and used as a proxy for genetic risk in models of family history × environmental risk interaction.ResultsIn proxy gene–environment interaction analysis, childhood adversity and cannabis use, and to a lesser extent urbanicity, displayed greater-than-additive risk if there was also evidence of familial affective liability. In addition, the interaction contrast ratio grew progressively greater across severity levels of psychosis admixture (none, attenuated psychosis, clinical psychosis) complicating affective dysregulation.ConclusionKnown environmental risks interact with familial evidence of affective liability in driving the level of psychosis admixture in states of early affective dysregulation in the general population, constituting an affective pathway to psychosis. There is interest in decomposing family history of affective liability into the environmental and genetic components that underlie the interactions as shown here.

BackgroundThe jumping to conclusions (JTC) reasoning bias and decreased working memory performance (WMP) are associated with psychosis, but associations with affective disturbances (i.e. depression, anxiety, mania) remain inconclusive. Recent findings also suggest a transdiagnostic phenotype of co-occurring affective disturbances and psychotic experiences (PEs). This study investigated whether JTC bias and decreased WMP are associated with co-occurring affective disturbances and PEs.MethodsData were derived from the second Netherlands Mental Health Survey and Incidence Study (NEMESIS-2). Trained interviewers administered the Composite International Diagnostic Interview (CIDI) at three time points in a general population sample (N = 4618). The beads and digit-span task were completed to assess JTC bias and WMP, respectively. CIDI was used to measure affective disturbances and an add-on instrument to measure PEs.ResultsCompared to individuals with neither affective disturbances nor PEs, the JTC bias was more likely to occur in individuals with co-occurring affective disturbances and PEs [moderate psychosis (1–2 PEs): adjusted relative risk ratio (RRR) 1.17, 95% CI 0.98–1.41; and high psychosis (3 or more PEs or psychosis-related help-seeking behaviour): adjusted RRR 1.57, 95% CI 1.19–2.08], but not with affective disturbances and PEs alone, whereas decreased WMP was more likely in all groups. There was some evidence of a dose–response relationship, as JTC bias and decreased WMP were more likely in individuals with affective disturbances as the level of PEs increased or help-seeking behaviour was reported.ConclusionThe findings suggest that JTC bias and decreased WMP may contribute to a transdiagnostic phenotype of co-occurring affective disturbances and PEs.

Background Mood and anxiety disorders are associated with growing burden of disease. Recent evidence shows that monitoring and enhancing positive mental health might be one direction to reduce this burden. The aim was to determine whether positive mental health predict recovery from mental disorders. Methods The study population consisted of 414 participants with a 12-month disorder from the representative general population Netherlands Mental Health Survey and Incidence Study-2. Independent positive mental health indicators were mental well-being, its subscales emotional, social and psychological well-being and the category flourishing mental health. Recovery was defined as no longer fulfilling DSM-IV criteria of the index disorder 3 years later. Results Despite meeting the criteria of a 12-month mental disorder, 19% with anxiety disorder were flourishing and 14% with mood disorder. Logistic regression analyses controlled for sociodemographics, physical health, life-events, service use, psychotropic medication, comorbidity and clinical severity showed that positive mental health positively influenced recovery from anxiety disorder (mainly by emotional and psychological well-being) and did not influence recovery from mood disorder. Limitations The results are not generalizable to psychiatric patients in treatment settings and might differ for specific disorders within each DSM-IV category. Conclusions Clinicians are encouraged to measure positive mental health in their patients and to improve positive mental health particularly in people with an anxiety disorder. The non-significant relation between positive mental health and recovery from mood disorder warrants further research, for example through using more in-depth assessment of positive mental health components and by investigating recovery from less severe mood disorders.

Hypotheses about the link between cannabis use and psychosis apply to the within-person level but have been tested mostly at the between-person level. We used a within-person design, in which a person serves as his own control, thus removing the need to consider confounding by any fixed (genetic and nongenetic) characteristic to study the prospective association between cannabis use and the incidence of attenuated psychotic experiences, and vice versa, adjusted for time-varying confounders. We combined 2 general population cohorts (at baseline: Early Developmental Stages of Psychopathology Study, n = 1395; Netherlands Mental Health Survey and Incidence Study-2, n = 6603), which applied a similar methodology to study cannabis use and attenuated psychotic experiences with repeated interviews (T0, T1, T2, and T3) over a period of approximately 10 years. The Hausman test was significant for the adjusted models, indicating the validity of the fixed-effects model. In the adjusted fixed-effects model, prior cannabis use was associated with psychotic experiences (aOR = 7.03, 95% CI: 2.39, 20.69), whereas prior psychotic experiences were not associated with cannabis use (aOR = 0.59, 95% CI: 0.21, 1.71). Longitudinal studies applying random-effects models to study associations between risk factors and mental health outcomes, as well as reverse causality, may not yield precise estimates. Cannabis likely impacts causally on psychosis but not the other way round.

Background It is unclear if childhood trauma (CT) is an independent risk factor of adult chronic physical disorders or whether its impact is (also) due to underlying poorer mental health. Methods Data were obtained from baseline measurements among 13,489 respondents of the Netherlands Mental Health Survey and Incidence Study-1 and -2, cohort studies of the Dutch general population aged 18–64 years. We used a childhood trauma questionnaire measuring emotional, psychological, physical or sexual trauma before the age of 16. Lifetime mood, anxiety and substance use disorders were assessed with the Composite International Diagnostic Interview version 1.1 and 3.0. A standard self-report checklist was used to assess a broad range of chronic physical disorders treated by a medical doctor in the previous 12 months. Results Respondents with a history of CT (N = 4054) suffered significantly more often from digestive (OR: 1.89–2.95), musculoskeletal (OR: 1.21–1.75) and respiratory disorders (OR: 1.39–1.91) and migraine (OR: 1.42–1.66). We found indirect associations between CT and digestive, musculoskeletal and respiratory disorders through lifetime mood (54%, 52% and 48% respectively), anxiety (44%, 55% and 44% respectively) and substance use disorders (33%, 23% and 38% respectively). Mood (69%) and anxiety disorders (67%) also impacted the relationship with migraine. Conclusions CT predicts the development of adult physical disorders, even after controlling for sociodemographic and lifestyle factors. This association is substantially influenced by mental health disorders. Treatment programs for CT should include interventions aimed at enhancing both mental and physical health.

How long does the average person sleep? Here, Kocevska et al. conducted a meta-analysis including over 1.1 million people to produce age- and sex-specific population reference charts for sleep duration and efficiency.We aimed to obtain reliable reference charts for sleep duration, estimate the prevalence of sleep complaints across the lifespan and identify risk indicators of poor sleep. Studies were identified through systematic literature search in Embase, Medline and Web of Science (9 August 2019) and through personal contacts. Eligible studies had to be published between 2000 and 2017 with data on sleep assessed with questionnaires including >= 100 participants from the general population. We assembled individual participant data from 200,358 people (aged 1-100 years, 55% female) from 36 studies from the Netherlands, 471,759 people (40-69 years, 55.5% female) from the United Kingdom and 409,617 people (>= 18 years, 55.8% female) from the United States. One in four people slept less than age-specific recommendations, but only 5.8% slept outside of the 'acceptable' sleep duration. Among teenagers, 51.5% reported total sleep times (TST) of less than the recommended 8-10 h and 18% report daytime sleepiness. In adults (>= 18 years), poor sleep quality (13.3%) and insomnia symptoms (9.6-19.4%) were more prevalent than short sleep duration (6.5% with TST < 6 h). Insomnia symptoms were most frequent in people spending >= 9 h in bed, whereas poor sleep quality was more frequent in those spending = 41 years) reported sleeping shorter times or slightly less efficiently than men, whereas with actigraphy they were estimated to sleep longer and more efficiently than man. This study provides age- and sex-specific population reference charts for sleep duration and efficiency which can help guide personalized advice on sleep length and preventive practices.

BackgroundAlthough hallucinations have been studied in terms of prevalence and its associations with psychopathology and functional impairment, very little is known about sensory modalities other than auditory (i.e. haptic, visual and olfactory), as well the incidence of hallucinations, factors predicting incidence and subsequent course.MethodsWe examined the incidence, course and risk factors of hallucinatory experiences across different modalities in two unique prospective general population cohorts in the same country using similar methodology and with three interview waves, one over the period 1996–1999 (NEMESIS) and one over the period 2007–2015 (NEMESIS-2).ResultsIn NEMESIS-2, the yearly incidence of self-reported visual hallucinations was highest (0.33%), followed by haptic hallucinations (0.31%), auditory hallucinations (0.26%) and olfactory hallucinations (0.23%). Rates in NEMESIS-1 were similar (respectively: 0.35%, 0.26%, 0.23%, 0.22%). The incidence of clinician-confirmed hallucinations was approximately 60% of the self-reported rate. The persistence rate of incident hallucinations was around 20–30%, increasing to 40–50% for prevalent hallucinations. Incident hallucinations in one modality were very strongly associated with occurrence in another modality (median OR = 59) and all modalities were strongly associated with delusional ideation (median OR = 21). Modalities were approximately equally strongly associated with the presence of any mental disorder (median OR = 4), functioning, indicators of help-seeking and established environmental risk factors for psychotic disorder.ConclusionsHallucinations across different modalities are a clinically relevant feature of non-psychotic disorders and need to be studied in relation to each other and in relation to delusional ideation, as all appear to have a common underlying mechanism.

Objective: To examine the longitudinal association between pain and suicidal ideation in the general adult population.Method: Data were used from two waves (baseline and three-year follow-up) of the Netherlands Mental Health Survey and Incidence Study-2. Persons without prior 12-month suicidal ideation at baseline were included in this study (N = 5242). Pain severity and interference due to pain in the past month were measured using the 36-item Short Form Health Survey. Suicidal ideation and DSM-IV mental disorders were assessed using the Composite International Diagnostic Interview. Logistic regression analyses were performed.Results: Moderate to very severe pain (OR 3.39, p Conclusion: Moderate to severe pain and interference due to pain are risk factors for suicidal ideation independently of concomitant mental disorders. We suggest taking assessment and management of suicidal ideation in patients with pain into account both in clinical treatment as well as in suicide prevention action plans.

Pain might be an important risk factor for common mental disorders. Insight into the longitudinal association between pain and common mental disorders in the general adult population could help improve prevention and treatment strategies. Data were used from the first 2 waves of the Netherlands Mental Health Survey and Incidence Study-2, a psychiatric epidemiological cohort study among the Dutch general population aged 18 to 64 years at baseline (N 5 5303). Persons without a mental disorder 12 months before baseline were selected as the at-risk group (n54974 for any mood disorder; n54979 for any anxiety disorder; and n55073 for any substance use disorder). Pain severity and interference due to pain in the past month were measured at baseline using the Short Form Health Survey. DSM-IV mental disorders were assessed at both waves using the Composite International Diagnostic Interview version 3.0. Moderate to very severe pain was associated with a higher risk of mood (odds ratio [OR] 5 2.10, 95% confidence interval [CI] 5 1.33-3.29) or anxiety disorders (OR 5 2.12, 95% CI 5 1.27-3.55). Moderate to very severe interference due to pain was also associated with a higher risk of mood (OR52.14, 95% CI51.30-3.54) or anxiety disorders (OR51.92, 95% CI 5 1.05-3.52). Pain was not significantly associated with substance use disorders. No interaction effects were found between pain severity or interference due to pain and a previous history of mental disorders. Moderate to severe pain and interference due to pain are strong risk factors for first-incident or recurrent mood and anxiety disorders, independent of other mental disorders. Pain management programs could therefore possibly also serve as a preventative program for mental disorders.

Background: The observed link between positive psychotic experiences (PE) and psychosis spectrum disorder (PSD) may be stronger depending on concomitant presence of PE with other dimensions of psychopathology. We examined whether the effect of common risk factors for PSD on PE is additive and whether the impact of risk factors on the occurrence of PE depends on the co-occurrence of other symptom dimensions (affective dysregulation, negative symptoms, and cognitive alteration).Method: Data from the Netherlands Mental Health Survey and Incidence Study 2 were used. Risk factors included childhood adversity, cannabis use, urbanicity, foreign born, hearing impairment, and family history of affective disorders. Logistic regression models were applied to test (1) the additive effect of risk factors (4 levels) on PE and (2) the moderating effects of symptom dimensions on the association between risk factors (present/absent) and PE, using additive interaction, expressed as the interaction contrast ratio.Results: Risk factors were additive: the greater the number of risk factors, the greater the odds of PE. Furthermore, concomitant presence of the other symptom dimensions all increased the impact of risk factors on PE. After controlling for age, sex, and education, only affective dysregulation and negative symptoms remained significant moderators; only affective dysregulation remained a significant moderator if all dimensions were adjusted for each other.Conclusions: Risk factors may not be directly associated with PE but additively give rise to a multidimensional subthreshold state anticipating the multidimensional clinical syndrome. Early motivational and cognitive impairments in the context of PE may be reducible to affective dysregulation.

Pain might be an important risk factor for common mental disorders. Insight into the longitudinal association between pain and common mental disorders in the general adult population could help improve prevention and treatment strategies. Data were used from the first 2 waves of the Netherlands Mental Health Survey and Incidence Study-2, a psychiatric epidemiological cohort study among the Dutch general population aged 18 to 64 years at baseline (N = 5303). Persons without a mental disorder 12 months before baseline were selected as the at-risk group (n = 4974 for any mood disorder; n = 4979 for any anxiety disorder; and n = 5073 for any substance use disorder). Pain severity and interference due to pain in the past month were measured at baseline using the Short Form Health Survey. DSM-IV mental disorders were assessed at both waves using the Composite International Diagnostic Interview version 3.0. Moderate to very severe pain was associated with a higher risk of mood (odds ratio [OR] = 2.10, 95% confidence interval [CI] = 1.33-3.29) or anxiety disorders (OR = 2.12, 95% CI = 1.27-3.55). Moderate to very severe interference due to pain was also associated with a higher risk of mood (OR = 2.14, 95% CI = 1.30-3.54) or anxiety disorders (OR = 1.92, 95% CI = 1.05-3.52). Pain was not significantly associated with substance use disorders. No interaction effects were found between pain severity or interference due to pain and a previous history of mental disorders. Moderate to severe pain and interference due to pain are strong risk factors for first-incident or recurrent mood and anxiety disorders, independent of other mental disorders. Pain management programs could therefore possibly also serve as a preventative program for mental disorders.

Purpose Psychosis has been associated with adult victimisation. However, it remains unclear whether psychosis predicts incident adult victimisation, or whether adult victimisation predicts incident psychosis. Furthermore, a moderating effect of childhood victimisation on the association between psychosis and adult victimisation has not been investigated. Methods The longitudinal association between baseline psychotic experiences and six-year incidence of adult victimisation was assessed in a prospective general population cohort of 6646 adults using logistic regression analysis. The association between baseline adult victimisation and six-year incidence of psychotic experiences was examined as well. Furthermore, the moderating effect of childhood victimisation on these bidirectional associations was analysed. Results Psychotic experiences and childhood victimisation were both associated with an increased risk of incident adult victimisation. However, this was through competing pathways, as suggested by a negative interaction between psychotic experiences and childhood victimisation. Baseline adult victimisation and childhood victimisation both independently increased the risk of incident psychotic experiences, but there was no interaction between adult victimisation and childhood victimisation. Conclusions Psychosis and victimisation are interconnected throughout the life course. Childhood victimisation is connected to psychosis through two pathways: one direct and one indirect through adult victimisation. In individuals without childhood victimisation, psychosis and adult victimisation bidirectionally impact on each other.

Background: Researchers have tried to identify more homogeneous subtypes of major depressive disorder (MDD) with latent class analyses (LCA). However, this approach does no justice to the dimensional nature of psychopathology. In addition, anxiety and functioning-levels have seldom been integrated in subtyping efforts. Therefore, this study used a hybrid discrete-dimensional approach to identify subgroups with shared patterns of depressive and anxiety symptomatology, while accounting for functioning-levels.Methods: The Comprehensive International Diagnostic Interview (CIDI) 1.1 was used to assess previous-year depressive and anxiety symptoms in the Netherlands Mental Health Survey and Incidence Study-1 (NEMESIS 1; n=5583). The data were analyzed with factor analyses, LCA and hybrid mixed-measurement item response theory (MM-IRT) with and without functioning covariates. Finally, the classes' predictors (measured one year earlier) and outcomes (measured two years later) were investigated.Results: A 3-class MM-IRT model with functioning covariates best described the data and consisted of a 'healthy class' (74.2%) and two symptomatic classes ('sleep/energy' [13.4%]; 'mood/anhedonia' [12.4%]). Factors including older age, urbanicity, higher severity and presence of 1-year MDD predicted membership of either symptomatic class vs. the healthy class. Both symptomatic classes showed poorer 2-year outcomes (i.e. disorders, poor functioning) than the healthy class. The odds of MDD after two years were especially increased in the mood/anhedonia class.Limitations: Symptoms were assessed for the past year whereas current functioning was assessed.Conclusions: Heterogeneity of depression and anxiety symptomatology are optimally captured by a hybrid discrete-dimensional subtyping model. Importantly, accounting for functioning-levels helps to capture clinically relevant interpersonal differences.

CONTEXT Credible research has not found any evidence that abortion causes mental disorders. It is not known, however, whether abortion-specific risk indicators and other variables are associated with the incidence or recurrence of mental disorders after abortion. METHODS As part of a prospective cohort study conducted in the Netherlands, 325 women were interviewed between April 2010 and January 2011, between 20 and 40 days after having an abortion; 264 were followed up an average of 2.7 years later. Associations between selected baseline variables and postabortion incident or recurrent mental disorders among the 199 women at risk were investigated using bivariate and multivariate logistic regression analyses. RESULTS Thirty-two percent of women at risk of an incident or recurrent mental disorder experienced one after the abortion. In multivariate analyses, no abortion-related variables (e.g., history of multiple abortions, second-trimester abortion, preabortion decision difficulty or uncertainty, and postabortion negative emotions) were associated with experience of any postabortion incident or recurrent mental disorders. The outcome was positively associated with having conceived within an unstable relationship (odds ratio, 3.0), number of negative life events in the past year (1.4) and having a history of mental disorders (2.4). CONCLUSIONS Correlates of postabortion mental disorders were variables that have been identified as general risk factors for mental disorders, which supports the idea that abortion does not pose specific risks to future mental health. Future research should investigate in what way unstable relationships, adverse life events and psychiatric history affect postabortion mental health.

Research in the field of mental health consequences of abortion is characterized by methodological limitations. We used exact matching on carefully selected confounders in a prospective cohort study of 325 women who had an abortion of an unwanted pregnancy and compared them 1-to-1 to controls who did not have this experience. Outcome measures were incidence and recurrence of common DSM-IV mental disorders (mood, anxiety, substance use disorders, and the aggregate measure 'any mental disorder') as measured with the Composite International Diagnostic Interview (CIDI) version 3.0, in the 2.5-3 years after the abortion. Although non-matched data suggested otherwise, women in the abortion group did not show significantly higher odds for incidence of 'any mental disorder', or mood, anxiety and substance use disorders, compared to matched controls who were similar in background variables but did not have an this experience. Having an abortion did not increase the odds for recurrence of the three disorder categories, but for any mental disorder the higher odds in the abortion group remained significant after matching. It is unlikely that termination of an unwanted pregnancy increases the risk on incidence of common mental disorders in women without a psychiatric history. However, it might increase the risk of recurrence among women with a history of mental disorders.