Longitudinal associations between alcohol use, smoking, genetic risk scoring and symptoms of depression in the general population: a prospective 6-year cohort study

BACKGROUND

Alcohol consumption, smoking and mood disorders are leading contributors to the global burden of disease and are highly comorbid. Yet, their interrelationships have remained elusive. The aim of this study was to examine the multi-cross-sectional and longitudinal associations between (change in) smoking and alcohol use and (change in) number of depressive symptoms.

METHODS

In this prospective, longitudinal study, 6646 adults from the general population were included with follow-up measurements after 3 and 6 years. Linear mixed-effects models were used to test multi-cross-sectional and longitudinal associations, with smoking behaviour, alcohol use and genetic risk scores for smoking and alcohol use as independent variables and depressive symptoms as dependent variables.

RESULTS

In the multi-cross-sectional analysis, smoking status and number of cigarettes per day were positively associated with depressive symptoms (p < 0.001). Moderate drinking was associated with less symptoms of depression compared to non-use (p = 0.011). Longitudinally, decreases in the numbers of cigarettes per day and alcoholic drinks per week as well as alcohol cessation were associated with a reduction of depressive symptoms (p = 0.001-0.028). Results of genetic risk score analyses aligned with these findings.

CONCLUSIONS

While cross-sectionally smoking and moderate alcohol use show opposing associations with depressive symptoms, decreases in smoking behaviour as well as alcohol consumption are associated with improvements in depressive symptoms over time. Although we cannot infer causality, these results open avenues to further investigate interventions targeting smoking and alcohol behaviours in people suffering from depressive symptoms.

The relationship between mental disorders and actual and desired subjective social status

AIMS

Mental disorders are associated with lower subjective social status (SSS), but a more nuanced understanding of this relationship is needed. We examined the influence of disorder age of onset and recency on SSS and studied whether mental disorders are also associated with the discrepancy between actual and desired SSS.

METHOD

Data are from the baseline and second wave of the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2). Mental disorders were assessed with the Composite International Diagnostic Interview (CIDI 3.0), while both actual and desired SSS were assessed with a ten-rung ladder. Linear regression was used to examine the association between mental disorders and SSS.

RESULTS

Of 5303 participants, 2237 had a lifetime mental disorder at baseline. These participants reported significantly lower actual SSS (6.28) at follow-up than healthy participants (6.66, B = -0.38 [95% CI -0.48 to -0.27], p < 0.001) and a significantly greater actual-desired SSS discrepancy (1.14 v. 1.05 after controlling for actual SSS, B = 0.09 [0.01-0.17], p = 0.024). Lower age of onset of the first mental disorder was marginally significantly associated with lower actual SSS (B = 0.006 [0.000-0.012], p = 0.046). More recent disorders were also associated with lower actual SSS (B = 0.015 [0.005-0.026], p = 0.005), such that participants whose disorder remitted ⩾6 years before baseline were statistically indistinguishable from healthy participants.

CONCLUSIONS

Lifetime mental disorders are associated with lower actual SSS and a slightly greater discrepancy between actual and desired SSS. However, people with mental disorders in (long-term) remission have a similar social status as healthy participants.

[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.

The decline in adolescent substance use across Europe and North America in the early twenty-first century: A result of the digital revolution?

Objectives

Increases in electronic media communication (EMC) and decreases in face-to-face peer contact in the evening (FTF) have been thought to explain the recent decline in adolescent substance use (alcohol, tobacco, cannabis). This study addresses this hypothesis, by examining associations between (time trends in) EMC, FTF, and substance use in more than 25 mainly European countries.

Methods

Using 2002–2014 data from the international Health Behaviour in School-aged Children (HBSC) study, we ran multilevel logistic regression analyses to investigate the above associations.

Results

National declines in substance use were associated with declines in FTF, but not with increases in EMC. At the individual level, both EMC and FTF related positively to substance use. For alcohol and cannabis use, the positive association with EMC was stronger in more recent years. Associations between EMC and substance use varied across countries, but this variation could not be explained by the proportion of young people using EMC within countries.

Conclusions

Our research suggests that the decrease in FTF, but not the increase in EMC, plays a role in the recent decrease in adolescent substance use.

Electronic supplementary material

The online version of this article (10.1007/s00038-018-1182-7) contains supplementary material, which is available to authorized users.

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.

[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.

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.

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.

[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.

Does social defeat mediate the association between childhood trauma and psychosis? Evidence from the NEMESIS-2 Study

OBJECTIVE

Based on theoretical considerations and animal studies, mediation of 'social defeat' (SD) in the association between childhood trauma (CT) and psychosis was investigated.

METHOD

Trained interviewers administered a structured interview assessing CT, psychotic experiences and other psychopathology in 6646 participants in the second Netherlands Mental Health Survey and Incidence Study (NEMESIS-2).

RESULTS

Childhood trauma was associated with psychotic experiences making up the extended psychosis phenotype (EPP), as well as with a diagnosis of psychotic disorder (PD). Similarly, CT was associated with a priori selected items indexing SD (discouraged, hopeless, worthless, loss of self-confidence, low self-esteem, better off dead, suicidal thoughts) and with a measure of affective dysregulation (AD), which in turn were also associated with psychosis. While SD and AD individually acted as mediators in the association between CT and EPP, only SD acted as a mediator in the association between CT and PD. Cannabis use did not mediate the association between CT and EPP or PD.

CONCLUSION

The present results suggest a developmental model implicating SD as an important mediator in the link between childhood adverse experiences and later development of psychotic experiences. The combined mediation by SD and AD is compatible with an 'affective pathway' to early psychosis.

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.

Sexual minority status and psychotic symptoms: findings from the Netherlands Mental Health Survey and Incidence Studies (NEMESIS)

BACKGROUND

Ethnic minority position is associated with increased risk for psychotic outcomes, which may be mediated by experiences of social exclusion, defeat and discrimination. Sexual minorities are subject to similar stressors. The aim of this study is to examine whether sexual minorities are at increased risk for psychotic symptoms and to explore mediating pathways.

METHOD

A cross-sectional survey was performed assessing cumulative incidence of psychotic symptoms with the Composite International Diagnostic Interview in two separate random general population samples (NEMESIS-1 and NEMESIS-2). Participants were sexually active and aged 18-64 years (n = 5927, n = 5308). Being lesbian, gay or bisexual (LGB) was defined as having sexual relations with at least one same-sex partner during the past year. Lifetime experience of any psychotic symptom was analysed using logistic regression, adjusted for gender, educational level, urbanicity, foreign-born parents, living without a partner, cannabis use and other drug use.

RESULTS

The rate of any psychotic symptom was elevated in the LGB population as compared with the heterosexual population both in NEMESIS-1 [odds ratio (OR) 2.56, 95% confidence interval (CI) 1.71-3.84] and NEMESIS-2 (OR 2.30, 95% CI 1.42-3.71). Childhood trauma, bullying and experience of discrimination partly mediated the association.

CONCLUSIONS

The finding that LGB orientation is associated with psychotic symptoms adds to the growing body of literature linking minority status with psychosis and other mental health problems, and suggests that exposure to minority stress represents an important mechanism.

[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.

[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.