[More treatment but no less depression. An uncomfortable paradox]

BACKGROUND

Treatments for depression have improved, and their availability has markedly increased since the 1980s. Mysteriously, the prevalence of depression in the general population has not decreased. This ‘treatment-prevalence paradox’ (TPP) raises fundamental questions about the diagnosis and treatment of depression.

AIM

To clarify the TPP.

METHOD

We discuss seven explanations for the TPP, based on an integrative narrative review.

RESULTS

The first two explanations assume that improved and more widely available treatments did reduce the prevalence, but that the reduction has been offset by an increase in: 1. misdiagnosing distress as depression, yielding more ‘false positive’ diagnoses; or 2. an actual increase in the incidence of first episodes. The remaining five explanations assume prevalence did not decrease, but suggest that 3. acute phase treatments and 4. relapse prevention are less efficacious than believed; 5. trial efficacy doesn’t generalize to real-world settings; 6. expansion of treatment was not optimally targeted at recurrent-chronic cases which account for most prevalence; and 7. treatments have sometimes counterproductive effects.

CONCLUSION

Our analysis suggest that there is little evidence that false positives or first incidence have increased as a result of error or fact but rather strong evidence that (a) the published literature overestimates treatment efficacy, that (b) treatments are considerably less effective as deployed in ‘real world’ settings, and (c) that treatment impact differs substantially for chronic-recurrent cases relative to non-recurrent cases. Collectively, these three explanations probably account for most of the paradox. Further exploration of counterproductive effects of treatment is critical. Significant prevalence reduction requires not only better treatment but foremost long-term structurally funded prevention targeting powerful determinants.

Stressful Events and Temperament Change during Early and Middle Adolescence: The TRAILS Study

This project investigates how stressful events are related to deviations from normative temperament development during adolescence. Temperament traits were assessed at ages 11 and 16 years. Life–event data was captured using an interview (total n = 1197). Normative changes were found in all traits. A linear trend was found between the experience of stressful events and temperament development. Adolescents exposed to stressful events showed smaller decreases in fear and shyness, stronger decreases in effortful control and affiliation and smaller increases in high intensity pleasure. Exposure to stressful events was related to increases in frustration instead of decreases. Our results show that whereas normative development is mostly in the direction of maturation, adolescents who experienced stressful events showed less maturation of their temperament. Copyright © 2011 John Wiley & Sons, Ltd.

[Antidepressants are frequently prescribed but still critized; a perspective on causes and solutions]

From around 1980, antidepressants (ad) have increasingly been prescribed, for longer periods of time, especially selective serotonin reuptake inhibitors (ssris). Paradoxically, their effectiveness is still doubted, especially outside the psychiatric profession.<br/> AIM: To explain increase and offer a perspective on causes and solutions, and to indicate how to reach consensus.<br/> METHOD: Position paper with critical analysis and synthesis of relevant literature.<br/> RESULTS: The rise in AD prescriptions results from: 1. increased safety and ease of prescribing, 2. increased presentation and recognition of depression in primary care, 3. extension of indication criteria, 4. effective marketing strategies, and 5. effectiveness in acute phase (aad) and of relapse/recurrence prevention in continuation/maintenance phases (coad).Critics point to: 1. low added value of aad relative to placebo, 2. many drop-outs and non-responders, 3. relapse/recurrence prevention with coad works only for responders to aad, 4. relapse/recurrence after AD discontinuation often involves withdrawal symptoms, and 5. publication bias, selective reporting, selective patient selection, and suboptimal blinding, resulting in overestimated effectiveness and underestimated disadvantages.Factors that keep fueling the controversy are: 1. critics stress the net effectiveness of AD whereas proponents point at gross effectiveness which includes spontaneous recovery and placebo effect; 2. persistence of distrust in industry-funded rcts; 3. ideological positions, reinforced by conflicts of interest and selective citations; 4. lack of rcts with relevant long-term outcome measurements.<br/> CONCLUSION: Although consensus is difficult to achieve given the ideological component, there are options. Three factors are critically important: confer to establish which data convince the opposition, response prediction (what works for whom), and rcts with long-term functional outcomes.

Beyond not bad or just okay: social predictors of young adults' wellbeing and functioning (a TRAILS study)

BACKGROUND

Various childhood social experiences have been reported to predict adult outcomes. However, it is unclear how different social contexts may influence each other's effects in the long run. This study examined the joint contribution of adolescent family and peer experiences to young adult wellbeing and functioning.

METHODS

Participants came from the TRacking Adolescents' Individual Lives Survey (TRAILS) study (n = 2230). We measured family and peer relations at ages 11 and 16 (i.e. family functioning, perceived parenting, peer status, peer relationship quality), and functioning as the combination of subjective wellbeing, physical and mental health, and socio-academic functioning at age 22. Using structural equation modelling, overall functioning was indicated by two latent variables for positive and negative functioning. Positive, negative and overall functioning at young adulthood were regressed on adolescent family experiences, peer experiences and interactions between the two.

RESULTS

Family experiences during early and mid-adolescence were most predictive for later functioning; peer experiences did not independently predict functioning. Interactions between family and peer experiences showed that both protective and risk factors can have context-dependent effects, being exacerbated or overshadowed by negative experiences or buffered by positive experiences in other contexts. Overall the effect sizes were modest at best.

CONCLUSIONS

Adolescent family relations as well as the interplay with peer experiences predict young adult functioning. This emphasizes the importance of considering the relative effects of one context in relation to the other.

The association between executive functioning and psychopathology: general or specific?

BACKGROUND

We modeled both psychopathology and executive function (EF) as bi-factor models to study if EF impairments are transdiagnostic or relate to individual syndromes, and concurrently, if such associations are with general EF or specific EF impairments.

METHODS

Data were obtained from the Tracking Adolescents' Individual Lives Survey (TRAILS; N = 2230). Psychopathology was assessed with parent-report questionnaires at ages 11, 14, 16, and 19, and EF with tasks from the Amsterdam Neuropsychological Tasks program at ages 11 and 19. Bi-factor models were fitted to the data using confirmatory factor analysis. Correlations were estimated to study the associations between general or specific components of both psychopathology and EF.

RESULTS

A bi-factor model with a general psychopathology factor, alongside internalizing (INT), externalizing, attention deficit/hyperactivity (ADHD), and autism spectrum (ASD) problem domains, and a bi-factor model with a general EF factor, alongside specific EFs were adequately fitting measurement models. The best-fitting model between EF and psychopathology showed substantial associations of specific EFs with the general psychopathology factor, in addition to distinct patterns of association with ASD, ADHD, and INT problems.

CONCLUSIONS

By studying very diverse psychopathology domains simultaneously, we show how EF impairments cross diagnostic boundaries. In addition to this generic relation, ADHD, ASD, and INT symptomatology show separable profiles of EF impairments. Thus, inconsistent findings in the literature may be explained by substantial transdiagnostic EF impairments. Whether general EF or specific EFs are related to psychopathology needs to be further studied, as differences in fit between these models were small.

Functional outcomes of child and adolescent mental disorders. Current disorder most important but psychiatric history matters as well

BACKGROUND

Various sources indicate that mental disorders are the leading contributor to the burden of disease among youth. An important determinant of functioning is current mental health status. This study investigated whether psychiatric history has additional predictive power when predicting individual differences in functional outcomes.

METHOD

We used data from the Dutch TRAILS study in which 1778 youths were followed from pre-adolescence into young adulthood (retention 80%). Of those, 1584 youths were successfully interviewed, at age 19, using the World Health Organization Composite International Diagnostic Interview (CIDI 3.0) to assess current and past CIDI-DSM-IV mental disorders. Four outcome domains were assessed at the same time: economic (e.g. academic achievement, social benefits, financial difficulties), social (early motherhood, interpersonal conflicts, antisocial behavior), psychological (e.g. suicidality, subjective well-being, loneliness), and health behavior (e.g. smoking, problematic alcohol, cannabis use).

RESULTS

Out of the 19 outcomes, 14 were predicted by both current and past disorders, three only by past disorders (receiving social benefits, psychiatric hospitalization, adolescent motherhood), and two only by current disorder (absenteeism, obesity). Which type of disorders was most important depended on the outcome. Adjusted for current disorder, past internalizing disorders predicted in particular psychological outcomes while externalizing disorders predicted in particular health behavior outcomes. Economic and social outcomes were predicted by a history of co-morbidity of internalizing and externalizing disorder. The risk of problematic cannabis use and alcohol consumption dropped with a history of internalizing disorder.

CONCLUSION

To understand current functioning, it is necessary to examine both current and past psychiatric status.

Neuroticism's prospective association with mental disorders halves after adjustment for baseline symptoms and psychiatric history, but the adjusted association hardly decays with time: a meta-analysis on 59 longitudinal/prospective studies with 443 313 participants

BACKGROUND

This meta-analysis seeks to quantify the prospective association between neuroticism and the common mental disorders (CMDs, including anxiety, depression, and substance abuse) as well as thought disorders (psychosis/schizophrenia) and non-specific mental distress. Data on the degree of confounding of the prospective association of neuroticism by baseline symptoms and psychiatric history, and the rate of decay of neuroticism's effect over time, can inform theories about the structure of psychopathology and role of neuroticism, in particular the vulnerability theory.

METHOD

This meta-analysis included 59 longitudinal/prospective studies with 443 313 participants.

RESULTS

The results showed large unadjusted prospective associations between neuroticism and symptoms/diagnosis of anxiety, depression, and non-specific mental distress (d = 0.50-0.70). Adjustment for baseline symptoms and psychiatric history reduced the associations by half (d = 0.10-0.40). Unadjusted prospective associations for substance abuse and thought disorders/symptoms were considerably weaker (d = 0.03-0.20), but were not attenuated by adjustment for baseline problems. Unadjusted prospective associations were four times larger over short (<4 year) than long (⩾4 years) follow-up intervals, suggesting a substantial decay of the association with increasing time intervals. Adjusted effects, however, were only slightly larger over short v. long time intervals. This indicates that confounding by baseline symptoms and psychiatric history masks the long-term stability of the neuroticism vulnerability effect.

CONCLUSION

High neuroticism indexes a risk constellation that exists prior to the development and onset of any CMD. The adjusted prospective neuroticism effect remains robust and hardly decays with time. Our results underscore the need to focus on the mechanisms underlying this prospective association.

Predicting mental disorders from hypothalamic-pituitary-adrenal axis functioning: a 3-year follow-up in the TRAILS study

BACKGROUND

Hypothalamic-pituitary-adrenal axis functioning, with cortisol as its major output hormone, has been presumed to play a key role in the development of psychopathology. Predicting affective disorders from diurnal cortisol levels has been inconclusive, whereas the predictive value of stress-induced cortisol concentrations has not been studied before. The aim of this study was to predict mental disorders over a 3-year follow-up from awakening and stress-induced cortisol concentrations.

METHOD

Data were used from 561 TRAILS (TRacking Adolescents' Individual Lives Survey) participants, a prospective cohort study of Dutch adolescents. Saliva samples were collected at awakening and half an hour later and during a social stress test at age 16. Mental disorders were assessed 3 years later with the Composite International Diagnostic Interview (CIDI).

RESULTS

A lower cortisol awakening response (CAR) marginally significantly predicted new disorders [odds ratio (OR) 0.77, p = 0.06]. A flat recovery slope predicted disorders with a first onset after the experimental session (OR 1.27, p = 0.04). Recovery revealed smaller, non-significant ORs when predicting new onset affective or anxiety disorders, major depressive disorder, or dependence disorders in three separate models, corrected for all other new onsets.

CONCLUSIONS

Our results suggest that delayed recovery and possibly reduced CAR are indicators of a more general risk status and may be part of a common pathway to psychopathology. Delayed recovery suggests that individuals at risk for mental disorders perceived the social stress test as less controllable and less predictable.

Why Not Everyone Gets Their Fair Share of Stress: Adolescent'S Perceived Relationship Affection Mediates Associations between Temperament and Subsequent Stressful Social Events

Temperamental differences are associated with subsequent stressful life events, a phenomenon that has in part been attributed to evocation. However, we remain ignorant about the mechanisms that mediate this process. In the current paper, we test whether differences in ‘perceived relationship affection’ accounted for part of the prospective association between temperament and stressful social event evocation in three social domains, viz. parents, peers and romantic partners. Data were derived from the Tracking Adolescents’ Individual Lives Survey, a large population cohort of Dutch adolescents ( n = 1158). Parent–reported adolescent temperament and adolescent's perceived affection were assessed at age 11 years. Stressful social events that occurred between age 11 and 16 years were captured using the event history calendar. Results indicate that adolescents evoke subsequent stressful social events based on their temperament, and that this association is partially mediated by perceived affection. Importantly, we found evidence for both generic and domain–specific associations, which indicates that social domains are related yet distinct. Taken together, the findings suggest that a search for mediating variables may be a promising way to increase our understanding of the mechanisms that underlie the social stress selection principle, and that perceived relationship affection is one of the candidates. Copyright © 2015 European Association of Personality Psychology

Mental health in Dutch adolescents: a TRAILS report on prevalence, severity, age of onset, continuity and co-morbidity of DSM disorders

BACKGROUND

With psychopathology rising during adolescence and evidence suggesting that adult mental health burden is often due to disorders beginning in youth, it is important to investigate the epidemiology of adolescent mental disorders.

METHOD

We analysed data gathered at ages 11 (baseline) and 19 years from the population-based Dutch TRacking Adolescents' Individual Lives Survey (TRAILS) study. At baseline we administered the Achenbach measures (Child Behavior Checklist, Youth Self-Report) and at age 19 years the World Health Organization's Composite International Diagnostic Interview version 3.0 (CIDI 3.0) to 1584 youths.

RESULTS

Lifetime, 12-month and 30-day prevalences of any CIDI-DSM-IV disorder were 45, 31 and 15%, respectively. Half were severe. Anxiety disorders were the most common but the least severe whereas mood and behaviour disorders were less prevalent but more severe. Disorders persisted, mostly by recurrence in mood disorders and chronicity in anxiety disorders. Median onset age varied substantially across disorders. Having one disorder increased subjects' risk of developing another disorder. We found substantial homotypic and heterotypic continuity. Baseline problems predicted the development of diagnosable disorders in adolescence. Non-intact families and low maternal education predicted externalizing disorders. Most morbidity concentrated in 5-10% of the sample, experiencing 34-55% of all severe lifetime disorders.

CONCLUSIONS

At late adolescence, 22% of youths have experienced a severe episode and 23% only mild episodes. This psychopathology is rather persistent, mostly due to recurrence, showing both monotypic and heterotypic continuity, with family context affecting particularly externalizing disorders. High problem levels at age 11 years are modest precursors of incident adolescent disorders. The burden of mental illness concentrates in 5-10% of the adolescent population.

Does neuroticism make you old? Prospective associations between neuroticism and leukocyte telomere length

BACKGROUND

Telomere attrition, causing accelerated aging, might be one of the mechanisms through which neuroticism leads to somatic disease and increased all-cause mortality. In the current study we investigated whether neuroticism is prospectively associated with shorter telomere length (TL), a biological marker of aging.

METHOD

Participants were 3432 adults (mean age 52.9 years, range 32-79). Data were collected at baseline (T1) and at two follow-up visits after 4 years (T2) and 6 years (T3). Neuroticism was assessed using the 12-item neuroticism scale of the Revised Eysenck Personality Questionnaire (EPQ-R) at T2 and T3. TL was measured by a monochrome multiplex quantitative polymerase chain reaction (PCR) assay at T1, T2 and T3. A linear mixed model was used to assess whether neuroticism could predict TL prospectively after adjusting for age, sex, body mass index (BMI), frequency of sports, smoking status, presence of chronic diseases and level of education.

RESULTS

Neuroticism was a significant negative predictor of TL at follow-up (B = -0.004, p = 0.044) after adjusting for sex, age, baseline TL and various biological and lifestyle factors.

CONCLUSIONS

High neuroticism is significantly and prospectively associated with telomere attrition independent of lifestyle and other risk factors.

Reciprocal effects of stable and temporary components of neuroticism and affective disorders: results of a longitudinal cohort study

BACKGROUND

Cross-sectional studies show that neuroticism is strongly associated with affective disorders. We investigated whether neuroticism and affective disorders mutually reinforce each other over time, setting off a potential downward spiral.

METHOD

A total of 2981 adults aged 18-65 years, consisting of healthy controls, persons with a prior history of affective disorders and persons with a current affective disorder were assessed at baseline (T1) and 2 (T2) and 4 years (T3) later. At each wave, affective disorders according to DSM-IV criteria were assessed with the Composite Interview Diagnostic Instrument (CIDI) version 2.1 and neuroticism with the Neuroticism-Extraversion-Openness Five Factor Inventory (NEO-FFI).

RESULTS

Using structural equation models the association of distress disorders (i.e. dysthymia, depressive disorder, generalized anxiety disorder) and fear disorders (i.e. social anxiety disorder, panic disorder, agoraphobia without panic) with neuroticism could be attributed to three components: (a) a strong correlation of the stable components of distress and fear disorders with the stable trait component of neuroticism; (b) a modest contemporaneous association of change in distress and fear disorders with change in neuroticism; (c) a small to modest delayed effect of change in distress and fear disorders on change in neuroticism. Moreover, neuroticism scores in participants newly affected at T2 but remitted at T3 did not differ from their pre-morbid scores at T1.

CONCLUSIONS

Our results do not support a positive feedback cycle of changes in psychopathology and changes in neuroticism. In the context of a relative stability of neuroticism and affective disorders, only modest contemporaneous and small to modest delayed effects of psychopathology on neuroticism were observed.

Negative and positive life events are associated with small but lasting change in neuroticism

BACKGROUND

High neuroticism is prospectively associated with psychopathology and physical health. However, within-subject changes in neuroticism due to life experiences (LEs) or state effects of current psychopathology are largely unexplored. In this 2-year follow-up study, four hypotheses were tested: (1) positive LEs (PLEs) decrease and negative LEs (NLEs) increase neuroticism; (2) LE-driven change in neuroticism is partly long-lasting; and (3) partly independent of LE-driven changes in anxiety/depression; and (4) childhood adversity (before age 16 years) moderates the influence of NLEs/PLEs on neuroticism scores in adult life.

METHOD

Data came from the Netherlands Study of Depression and Anxiety [NESDA, n = 2981, mean age 41.99 years (s.d. = 13.08), 66.6% women]. At follow-up (T₂) we assessed PLEs/NLEs with the List of Threatening Experiences (LTE) over the prior 24 months and categorized them over recent and distant PLE/NLE measures (1-3 and 4-24 months prior to T₂ respectively) to distinguish distant NLE/PLE-driven change in trait neuroticism (using the Dutch version of the Neuroticism-Extroversion-Openness Five Factor Inventory, NEO-FFI) from state deviations due to changes in symptoms of depression (self-rated version of the 30-item Inventory of Depressive Symptomatology, IDS-SR30) and anxiety (Beck Anxiety Inventory, BAI).

RESULTS

Distant NLEs were associated with higher and distant PLEs with lower neuroticism scores. The effects of distant LEs were weak but long-lasting, especially for distant PLEs. Distant NLE-driven change in neuroticism was associated with change in symptoms of anxiety/depression whereas the effect of distant PLEs on neuroticism was independent of any such changes. Childhood adversity weakened the impact of distant NLEs but enhanced the impact of distant PLEs on neuroticism.

CONCLUSIONS

Distant PLEs are associated with small but long-lasting decreases in neuroticism regardless of changes in symptom levels of anxiety/depression. Long-lasting increases in neuroticism associated with distant NLEs are mediated by anxiety/depression.

Physical activity and onset of depression in adolescents: a prospective study in the general population cohort TRAILS

Although it has often been suggested that physical activity and depression are intertwined, only few studies have investigated whether specific aspects of physical activity predict the incidence of major depression in adolescents from the general population. Therefore the aim of this study was to investigate the effects of nature, frequency, duration and intensity of physical activity during early adolescence on the onset of a major depressive episode in early adulthood. In a population sample of adolescents (N = 1396), various aspects of physical activity were assessed at early adolescence (mean age 13.02, SD = 0.61). Major depressive episode onset was assessed using the Composite International Diagnostic Interview. A Cox regression model was performed to investigate whether physical activity characteristics and their interactions with gender predicted a major depressive episode onset up until mean age 18.5 (SD = 0.61). The individual characteristics of physical activity (nature, frequency, duration and intensity) or their interactions with gender did not predict a major depressive episode onset (p values >0.05). So far, there is no prospective evidence that physical activity protects against the development of adolescent depressive episodes in either boys or girls.

Early trauma and familial risk in the development of the extended psychosis phenotype in adolescence

OBJECTIVE

Both genetic and environmental factors are thought to play a role in the development of psychotic outcomes; however, their respective contributions over time, including possible developmental interactions, remain largely unknown.

METHOD

The contribution of parental general and psychotic psychopathology as proxies of genetic risk to the development of subthreshold psychosis and its hypothesized interaction with childhood trauma were studied in a general population sample of 2230 adolescents, followed from age 10-16 years. Outcome measures were: i) level of psychotic experiences at age 16 years and ii) persistence of such experiences over the total follow-up period.

RESULTS

General parental psychopathology was associated with CAPE score (OR = 1.08; P < 0.043 for highest quintile) and suggestively predicted psychosis persistence (OR, 1.16; P < 0.072). Psychotic parental psychopathology was suggestively associated with CAPE score (OR, 2.25; P < 0.063 for highest quintile), predicted membership of the Persistent group (OR, 3.72; P < 0.039) and suggestively predicted membership of the Decreasing group (OR 2.04; P < 0.051). Childhood trauma was associated with CAPE score and with all developmental trajectories of subclinical psychosis. No evidence was found for an interaction between trauma and parental psychopathology.

CONCLUSION

The development and persistence of subthreshold psychotic symptoms may be conditional on non-interacting proxy genetic and environmental influences.

Moderators of the synchrony of change between decreasing depression severity and disability

OBJECTIVE

To identify moderators of synchrony of change between depression severity and disability.

METHOD

From a large cohort study with 2 years of follow-up, patients with major depressive disorder at baseline who decreased at least 25% in depression severity after 2 years (n = 245) were selected. We measured overall and domain-specific disability at baseline, and at 1- and 2-year follow-up. Possible moderators, among which several demographic, clinical, personality, and contextual factors, were measured at baseline. We used linear mixed models to analyze the data.

RESULTS

Decrease in depression severity correlated strongly with reductions of overall disability (r = 0.54). Synchrony of change for the disability domains ranged from 0.13 for self-care to 0.47 for participation. From the possible moderators, only age and work stress moderated the association between change in depression severity and disability, with stronger synchrony of change among younger patients and patients who experienced moderate work stress.

CONCLUSION

Strong synchrony of change exists between depression severity and disability. Perhaps, because of the strength of this synchrony, few contextual characteristics moderated the association. Clinicians should be aware of the risk of slower or incomplete functional recovery in older people and those without a job or those experiencing low work stress.

An increase in depressive symptoms after myocardial infarction predicts new cardiac events irrespective of depressive symptoms before myocardial infarction

BACKGROUND

Depression after myocardial infarction (MI) is associated with poor cardiovascular prognosis. There is some evidence that specifically depressive episodes that develop after the acute event are associated with poor cardiovascular prognosis. The aim of the present study was to evaluate whether an increase in the number of depressive symptoms after MI is associated with new cardiac events.

METHOD

In 442 depressed and 325 non-depressed MI patients the Composite International Diagnostic Interview interview to assess post-MI depression was extended to evaluate the presence of the ICD-10 depressive symptoms just before and after the MI. The effect of an increase in number of depressive symptoms during the year following MI on new cardiac events up to 2.5 years post-MI was assessed with Cox regression analyses.

RESULTS

Each additional increase of one symptom was significantly associated with a 15% increased risk of new cardiac events, and this was stronger for non-depressed than for depressed patients. This association was independent of baseline cardiac disease severity. There was no interaction with the number of depressive symptoms pre-MI.

CONCLUSIONS

Our findings suggest that an increase in depressive symptoms after MI irrespective of the state of depression pre-MI explains why post-MI depression is associated with poor cardiovascular prognosis. Also increases in depressive symptoms after MI resulting in subthreshold depression should be evaluated as a prognostic marker. Whether potential mechanisms such as cardiac disease severity or inflammation underlie the association remains to be clarified.

[Symptoms of anxiety in adolescents. Findings from the TRAILS-study]

BACKGROUND

The Dutch TRAILS-study focuses on development from early adolescence into adulthood. An important aspect of this development is the development of anxiety. Hitherto little has been known about typical development of symptoms of anxiety during adolescence.

AIM

To describe both the normative development of anxiety during adolescence, and the risk indicators for high levels of anxiety in adolescents.

METHOD

Studies were embedded in trails, a large cohort study that followed children from the age of 10 to adulthood.

RESULTS

Our results showed that, on average, levels of anxiety decrease in early adolescence and subsequently increase in middle or late adolescence, depending on the subtype of anxiety involved. Child-, parent- and peer-factors at age 10-12 years were related to higher subsequent anxiety levels. Some factors, such as the style of upbringing, were related to higher anxiety levels solely in early adolescence, whereas other factors such as being bullied by peers were related to continuing higher anxiety levels throughout adolescence, irrespective of later victimisation.

CONCLUSION

Our study should, we hope, lead to a better understanding of the normative development of anxiety in the general adolescent population.

Days out of role due to common physical and mental conditions: results from the WHO World Mental Health surveys

Days out of role because of health problems are a major source of lost human capital. We examined the relative importance of commonly occurring physical and mental disorders in accounting for days out of role in 24 countries that participated in the World Health Organization (WHO) World Mental Health (WMH) surveys. Face-to-face interviews were carried out with 62 971 respondents (72.0% pooled response rate). Presence of ten chronic physical disorders and nine mental disorders was assessed for each respondent along with information about the number of days in the past month each respondent reported being totally unable to work or carry out their other normal daily activities because of problems with either physical or mental health. Multiple regression analysis was used to estimate associations of specific conditions and comorbidities with days out of role, controlling by basic socio-demographics (age, gender, employment status and country). Overall, 12.8% of respondents had some day totally out of role, with a median of 51.1 a year. The strongest individual-level effects (days out of role per year) were associated with neurological disorders (17.4), bipolar disorder (17.3) and post-traumatic stress disorder (15.2). The strongest population-level effect was associated with pain conditions, which accounted for 21.5% of all days out of role (population attributable risk proportion). The 19 conditions accounted for 62.2% of all days out of role. Common health conditions, including mental disorders, make up a large proportion of the number of days out of role across a wide range of countries and should be addressed to substantially increase overall productivity.

A multinational study of mental disorders, marriage, and divorce

OBJECTIVE

Estimate predictive associations of mental disorders with marriage and divorce in a cross-national sample.

METHOD

Population surveys of mental disorders included assessment of age at first marriage in 19 countries (n = 46,128) and age at first divorce in a subset of 12 countries (n = 30,729). Associations between mental disorders and subsequent marriage and divorce were estimated in discrete time survival models.

RESULTS

Fourteen of 18 premarital mental disorders are associated with lower likelihood of ever marrying (odds ratios ranging from 0.6 to 0.9), but these associations vary across ages of marriage. Associations between premarital mental disorders and marriage are generally null for early marriage (age 17 or younger), but negative associations come to predominate at later ages. All 18 mental disorders are positively associated with divorce (odds ratios ranging from 1.2 to 1.8). Three disorders, specific phobia, major depression, and alcohol abuse, are associated with the largest population attributable risk proportions for both marriage and divorce.

CONCLUSION

This evidence adds to research demonstrating adverse effects of mental disorders on life course altering events across a diverse range of socioeconomic and cultural settings. These effects should be included in considerations of public health investments in preventing and treating mental disorders.

Evidence for a persistent, environment-dependent and deteriorating subtype of subclinical psychotic experiences: a 6-year longitudinal general population study

BACKGROUND

Research suggests that subclinical psychotic experiences during adolescence represent the behavioral expression of liability for psychosis. Little is known, however, about the longitudinal trajectory of liability in general population samples.

METHOD

Growth mixture modeling was used to examine longitudinal trajectories of self-reported positive psychotic experiences in the Youth Self Report (YSR), completed three times over a period of 6 years by a general population cohort of adolescents aged 10-11 years at baseline (n=2230).

RESULTS

Four groups with distinct developmental trajectories of low, decreasing, increasing and persistent levels of mild positive psychotic experiences were revealed. The persistent trajectory was associated strongly with cannabis use, childhood trauma, developmental problems and ethnic minority status, and consistently displayed strong associations with factors known to predict transition from subclinical psychotic experience to clinical psychotic disorder (severity of and secondary distress due to psychotic experiences, social and attentional problems and affective dysregulation) and also with high levels of parental-reported psychotic experiences and use of mental health care at the end of the follow-up period. Progressively weaker associations were found for the increasing, decreasing and low trajectories respectively.

CONCLUSIONS

The results suggest that the outcome of early developmental deviation associated with later expression of psychotic experiences is contingent on the degree of later interaction with environmental risks inducing, first, persistence of psychotic experiences and, second, progression to onset of need for care and service use. Insight into the longitudinal dynamics of risk states in representative samples may contribute to the development of targeted early intervention in psychosis.

Explaining heterogeneity in disability with major depressive disorder: effects of personal and environmental characteristics

BACKGROUND

Major depressive disorder (MDD) is associated with disability, yet some patients function surprisingly well. The reason for this heterogeneity between patients is unclear. Building on the International Classification of Functioning (ICF) model, this study aims to examine effects of personal and environmental characteristics on disability with MDD, over and above illness characteristics.

METHODS

Data were obtained from 573 patients with a current diagnosis of MDD. Three measures for disability were used, varying in objectivity and specificity: 'WHODAS disability', 'days out of role', and 'work absence'. Univariate and stepwise multivariate regression analyses were conducted.

RESULTS

WHODAS disability was best explained by the study variables. Illness characteristics were clearly the strongest correlates of WHODAS disability, whereas personal and environmental characteristics were less influential. Personal and, more restrictedly, environmental characteristics were almost equally important to illness characteristics in explaining days out of role and work absence. High conscientiousness, high neuroticism, low level of physical activity, and high work stress were the strongest predictors of disability among MDD patients.

LIMITATIONS

Due to the cross-sectional design of the present study we could not draw conclusions about causal relationships between our predictor variables and disability.

CONCLUSIONS

Personal characteristics appeared to be almost equally important to illness characteristics in explaining heterogeneity in disability when measured objectively and specifically (i.e., days out of role and work absence). However, personal characteristics turned out to be considerably less important to disability measured in a broad and subjective way (i.e., WHODAS disability). Environmental characteristics appeared to have little impact.

Risk indicators of anxiety throughout adolescence: the TRAILS study

BACKGROUND

The aim was to identify risk indicators from preadolescence (age period 10-12) that significantly predict unfavorable deviations from normal anxiety development throughout adolescence (age period 10-17 years).

METHODS

Anxiety symptoms were assessed in a community sample of 2,220 boys and girls at three time-points across a 5-year interval. Risk indicators were measured at baseline and include indicators from the child, family, and peer domain. Associations with anxiety were measured with multilevel growth curve analyses.

RESULTS

A stable difference in anxiety over adolescence was found between high and low levels of a range of child factors (frustration, effortful control), family factors (emotional warmth received from parents, lifetime parental internalizing problems), and peer factor (victims of bullying) (P <.001). In contrast, the difference in anxiety between high and low levels of factors, such as self-competence, unfavorable parenting styles, and bully victims, decreased over adolescence (P <.001). For other family factors, associations were weaker (.05 <P <.001). Associations with parental education and family composition were not significant. Adjustment for concurrent depressive symptoms attenuated the associations, but those that were significant at P <.001 remained to be so. Specificity for anxiety subtypes (generalized anxiety, separation anxiety, social phobia, panic, and obsessive-compulsive symptoms) was reported for each association.

CONCLUSIONS

Several child, family, and peer factors measured in preadolescence were risk indicators of high levels of anxiety symptoms throughout adolescence. Some factors (such as rejective parenting) were vulnerability indicators for anxiety in early adolescence only, whereas other factors (such as peer victimization) were indicators of long-term elevated anxiety levels.

Presence of individual (residual) symptoms during depressive episodes and periods of remission: a 3-year prospective study

BACKGROUND

Residual depressive symptomatology constitutes a substantial risk for relapse in depression. Treatment until full remission is achieved is therefore implicated. However, there is a lack of knowledge about the prevalence of (1) residual symptoms in general and (2) the individual residual symptoms in particular.

METHOD

In a 3-year prospective study of 267 initially depressed primary care patients we established per week the presence/absence of the individual DSM-IV depressive symptoms during subsequent major depressive episodes (MDEs) and episodes of (partial) remission. This was accomplished by means of 12 assessments at 3-monthly intervals with the Composite International Diagnostic Interview (CIDI).

RESULTS

In general, residual depressive symptomatology was substantial, with on average two symptoms present during remissions. Three individual symptoms (cognitive problems, lack of energy and sleeping problems) dominated the course of depression and were present 85-94% of the time during depressive episodes and 39-44% of the time during remissions.

CONCLUSIONS

Residual symptoms are prevalent, with some symptoms being present for almost half of the time during periods of remission. Treatment until full remission is achieved is not common practice, yet there is a clear need to do so to prevent relapse. Several treatment suggestions are made.

DRD2 and DRD4 in relation to regular alcohol and cannabis use among adolescents: does parenting modify the impact of genetic vulnerability? The TRAILS study

AIMS

The aims of the present study were to determine the direct effect of DRD2 and DRD4, as well as their interaction with parenting (i.e. rejection, overprotection and emotional warmth), on the development of regular alcohol and cannabis use in 1192 Dutch adolescents from the general population.

METHODS

Information was obtained by self-report questionnaires. Perceived rejection, overprotection and emotional warmth were assessed at age 10-12. Regular alcohol and cannabis use were determined at age 15-18 and defined as the consumption of alcohol on 10 or more occasions in the past four weeks, and the use of cannabis on 4 or more occasions in the past four weeks. Models were adjusted for age, sex, parental alcohol or cannabis use, and externalizing behavior.

RESULTS

Carrying the A1 allele of the DRD2 TaqIA polymorphism, or the 7 repeat DRD4, was not directly related to regular alcohol or cannabis use. In addition, adolescent carriers of these genetic risk markers were not more susceptible to the influence of less optimal parenting. Main effects for parenting indicated that overprotection increased the risk of regular alcohol use, whereas the risk of cannabis use was enhanced by parental rejection and buffered by emotional warmth.

CONCLUSIONS

Our findings do not support an association between DRD2/DRD4 and regular alcohol and cannabis use in adolescents. Given the substance-specific influences of rejection, overprotection and emotional warmth, these parenting factors might be promising candidates for prevention work.

Including information about co-morbidity in estimates of disease burden: results from the World Health Organization World Mental Health Surveys

BACKGROUND

The methodology commonly used to estimate disease burden, featuring ratings of severity of individual conditions, has been criticized for ignoring co-morbidity. A methodology that addresses this problem is proposed and illustrated here with data from the World Health Organization World Mental Health Surveys. Although the analysis is based on self-reports about one's own conditions in a community survey, the logic applies equally well to analysis of hypothetical vignettes describing co-morbid condition profiles.

METHOD

Face-to-face interviews in 13 countries (six developing, nine developed; n=31 067; response rate=69.6%) assessed 10 classes of chronic physical and nine of mental conditions. A visual analog scale (VAS) was used to assess overall perceived health. Multiple regression analysis with interactions for co-morbidity was used to estimate associations of conditions with VAS. Simulation was used to estimate condition-specific effects.

RESULTS

The best-fitting model included condition main effects and interactions of types by numbers of conditions. Neurological conditions, insomnia and major depression were rated most severe. Adjustment for co-morbidity reduced condition-specific estimates with substantial between-condition variation (0.24-0.70 ratios of condition-specific estimates with and without adjustment for co-morbidity). The societal-level burden rankings were quite different from the individual-level rankings, with the highest societal-level rankings associated with conditions having high prevalence rather than high individual-level severity.

CONCLUSIONS

Plausible estimates of disorder-specific effects on VAS can be obtained using methods that adjust for co-morbidity. These adjustments substantially influence condition-specific ratings.

Explaining heterogeneity in disability associated with current major depressive disorder: effects of illness characteristics and comorbid mental disorders

BACKGROUND

Although major depressive disorder (MDD) is associated with disability, some persons do function well despite their illness. Aim of the present study was to examine the effect of illness characteristics and comorbid mental disorders on various aspects of disability among persons with a current MDD episode.

METHODS

Data were derived from 607 participants with a current MDD based on the Composite International Diagnostic Interview (CIDI). Severity was assessed via the Inventory of Depressive Symptoms self-report (IDS-SR). For disability three outcome measures were used: World Health Organization Disability Assessment Schedule II (WHODAS) disability and its 7 dimensions, days out of role, and work absence. Using multiple regression analysis the effects of MDD characteristics and comorbid mental disorders were estimated.

RESULTS

The IDS-SR score was the best predictor of all disability outcomes. Of the comorbid mental disorders, agoraphobia was significantly associated with overall disability. Collectively, all illness characteristics accounted for 43% of variance in WHODAS disability, 13% in days out of role and 10% in work absence, suggesting substantial unexplained variance.

LIMITATIONS

Only self-report measures of disability were used. There were no assessments of other diagnoses than depressive, anxiety and alcohol use disorders.

CONCLUSIONS

Although heterogeneity in disability of persons with current MDD is partially explained by illness characteristics of MDD (especially symptom severity) and comorbid mental disorders, most of the variance is not accounted for.

Schizotypy and brain structure: a voxel-based morphometry study

BACKGROUND

Schizotypy is conceptualized as a subclinical manifestation of the same underlying biological factors that give rise to schizophrenia and other schizophrenia spectrum disorders. Individuals with psychometric schizotypy (PS) experience subthreshold psychotic signs and can be psychometrically identified among the general population. Previous research using magnetic resonance imaging (MRI) has shown gray-matter volume (GMV) abnormalities in chronic schizophrenia, in subjects with an at-risk mental state (ARMS) and in individuals with schizotypal personality disorder (SPD). However, to date, no studies have investigated the neuroanatomical correlates of PS.

METHOD

Six hundred first- and second-year university students completed the Community Assessment of Psychic Experiences (CAPE), a self-report instrument on psychosis proneness measuring attenuated positive psychotic experiences. A total of 38 subjects with high and low PS were identified and subsequently scanned with MRI. Voxel-based morphometry (VBM) was applied to examine GMV differences between subjects with high and low positive PS.

RESULTS

Subjects with high positive PS showed larger global volumes compared to subjects with low PS, and larger regional volumes in the medial posterior cingulate cortex (PCC) and the precuneus. There were no regions where GMV was greater in low than in high positive PS subjects.

CONCLUSIONS

These regions, the PCC and precuneus, have also been sites of volumetric differences in MRI studies of ARMS subjects and schizophrenia, suggesting that psychotic or psychotic-like experiences may have common neuroanatomical correlates across schizophrenia spectrum disorders.

Gender and the relationship between marital status and first onset of mood, anxiety and substance use disorders

BACKGROUND

Prior research on whether marriage is equally beneficial to the mental health of men and women is inconsistent due to methodological variation. This study addresses some prior methodological limitations and investigates gender differences in the association of first marriage and being previously married, with subsequent first onset of a range of mental disorders.

METHOD

Cross-sectional household surveys in 15 countries from the WHO World Mental Health survey initiative (n=34493), with structured diagnostic assessment of mental disorders using the Composite International Diagnostic Interview 3.0. Discrete-time survival analyses assessed the interaction of gender and marital status in the association with first onset of mood, anxiety and substance use disorders.

RESULTS

Marriage (versus never married) was associated with reduced risk of first onset of most mental disorders in both genders; but for substance use disorders this reduced risk was stronger among women, and for depression and panic disorder it was confined to men. Being previously married (versus stably married) was associated with increased risk of all disorders in both genders; but for substance use disorders, this increased risk was stronger among women and for depression it was stronger among men.

CONCLUSIONS

Marriage was associated with reduced risk of the first onset of most mental disorders in both men and women but there were gender differences in the associations between marital status and onset of depressive and substance use disorders. These differences may be related to gender differences in the experience of multiple role demands within marriage, especially those concerning parenting.

Subthreshold depression based on functional impairment better defined by symptom severity than by number of DSM-IV symptoms

BACKGROUND

Depression with fewer symptoms than required for a DSM-IV diagnosis of Major Depressive Disorder (MDD) has consistently been found to be associated with functional impairment. In this study, we aim to define clinically significant depression below the DSM-IV threshold for Major Depressive Disorder (MDD) by means of functional impairment.

METHODS

Data used are from 2157 respondents of the Netherlands Study of Depression and Anxiety (NESDA). The Composite International Diagnostic Interview (CIDI) and the Inventory for Depressive Symptomatology-Self Report (IDS-SR(30)) were compared in their association with functional impairment as measured by the World Health Organization Disability Assessment Schedule II (WHODAS II). We used ANCOVA, adjusting for gender, age, education and somatic conditions, and ROC analyses.

RESULTS

The IDS-SR(30) (p<.001, eta(2)=.51) was more strongly associated with functional impairment than CIDI symptom count (p<.001, eta(2)=.035). Effect sizes supported four symptoms on the CIDI, and a score within the mild depression range on the IDS-SR(30) as adequate cut-offs for defining subthreshold depression, respectively. ROC analyses showed that these cut-offs identified the top 10% and 8% to 60% most dysfunctional respondents, respectively.

LIMITATIONS

Suggested cut-offs seem reasonable on the basis of converging findings, but in lack of a golden standard they remain somewhat arbitrary. Furthermore, the design of the study is cross-sectional in nature, no causal inferences between depression and functional impairment can be made.

CONCLUSIONS

Although both instruments are associated with functional impairment, the IDS-SR(30) seems better suited than the CIDI to define subthreshold depression, with a cut-off in the mild IDS-SR(30) range.

Are attitudes towards mental health help-seeking associated with service use? Results from the European Study of Epidemiology of Mental Disorders

OBJECTIVE

To investigate the prevailing attitudes towards mental health help-seeking in Europe, their correlates, and whether these attitudes are associated with actual service use for mental health problems.

METHOD

Data were derived from the European Study of Epidemiology of Mental Disorders, a survey representative of the adult population of six countries: Belgium, France, Germany, Italy, the Netherlands and Spain (n = 8,796). The World Mental Health Composite International Diagnostic Interview was used to assess attitudes and DSM-IV diagnoses. The attitudes referred to beliefs that the respondents would seek professional help when faced with a serious emotional problem, would feel comfortable talking about personal problems with a professional, would not be embarrassed if friends knew about the professional help, and respondents' perceived effectiveness of mental health care.

RESULTS

Almost a third of the respondents held the view that professional care was worse than or equal to no help when faced with serious emotional problems. Female gender, being younger than 65 years of age, high income, living in Spain or Italy, presence of mood disorder and previous service use were associated with at least two of the four assessed attitudes towards mental health help-seeking. All four attitudes were significantly associated with mental health care use, also after adjustment for previous service use.

CONCLUSION

The low perceived effectiveness of professional care calls for serious action aiming to improve the visibility and credibility of the mental health care sector.

[Attitudes to the seeking of psychiatric help from mental health care professionals and actually seeking help: differences in Europe]

BACKGROUND

Little is known about attitudes to seeking help from mental health care professionals.

AIM

To investigate these attitudes and their correlates, and find out whether these attitudes are associated with the use of care services.

METHOD

Data were derived from the European Study of Epidemiology of Mental Disorders, a survey that is representative of the adult population of six countries (n = 8,796).

RESULTS

Almost a third of respondents were of the opinion that professional help was worse than or equivalent to no help at all, in relation to serious psychiatric problems. Females, respondents under the age of 65, with a higher income, living in Spain or Italy, with a mood disorder, and those who had previously sought mental health care, more often stated that they would seek professional help if beset by a serious mental health problem. All these groups, except for the younger than 65, also reported more often that they would feel comfortable discussing mental health problems with a professional or that they were receiving this kind of help. All these attitudes were associated with an increased chance that persons would use professional help if beset by mental health problems.

CONCLUSION

Definite steps need to be taken to increase the visibility and credibility of the mental health services.

The developmental course of anxiety symptoms during adolescence: the TRAILS study

BACKGROUND

Little is known about the development of anxiety symptoms from late childhood to late adolescence. The present study determined developmental trajectories of symptoms of separation anxiety disorder (SAD), social phobia (SoPh), generalized anxiety disorder (GAD), panic disorder (PD), and obsessive-compulsive disorder (OCD) in a large prospective community cohort.

METHODS

Anxiety symptoms were assessed in a community sample of 2220 boys and girls at three time-points across a 5-year interval. The Revised Child Anxiety and Depression Scale (RCADS) was used to assess anxiety symptoms, and multilevel growth-curve analyses were performed.

RESULTS

All subtypes of anxiety first showed a decrease in symptoms (beta for age ranged from -.05 to -.13, p < .0001), followed by a leveling off of the decrease, and a subsequent slight increase in symptoms (beta for age-squared ranged from .006 to .01, p < .0001) from middle adolescence (GAD, SoPh, SAD) or late adolescence (PD and OCD) onwards. This increase in anxiety symptoms could not be explained by a co-occurring increase in depression symptoms. Girls had more anxiety symptoms than boys, and this difference remained stable during adolescence (p < .0001). Gender differences were strongly attenuated by adjustment for symptoms of depression.

CONCLUSIONS

The current study shows that, in the general population, anxiety symptoms first decrease during early adolescence, and subsequently increase from middle to late adolescence. These findings extend our knowledge on the developmental course of anxiety symptoms during adolescence. This is the first study to separate the development of anxiety symptoms from that of symptoms of depression.

Baseline cortisol measures and developmental pathways of anxiety in early adolescence

OBJECTIVE

This study investigated whether baseline cortisol measures predicted future anxiety, and compared cortisol values of groups with different developmental pathways of anxiety.

METHOD

Cortisol levels were assessed in 1768 individuals (10-12 years). Anxiety levels were assessed at the same age and 2 years later.

RESULTS

Cortisol measures did not predict future anxiety levels. Individuals with persistent anxiety problems did not show higher morning cortisol levels than those with persistently low, decreasing, or increasing anxiety levels. Instead, individuals with persistently high anxiety levels showed significantly lower evening cortisol levels than all other individuals. Further, participants with increasing anxiety levels showed higher morning cortisol levels (area under the curve; AUC) than individuals with persistently low anxiety levels.

CONCLUSION

The extent to which the HPA-axis - by itself - plays a role in the aetiology of anxiety is questionable. Interactions of the HPA-axis with other biological or environmental factors may be more important.

Mental disorders and termination of education in high-income and low- and middle-income countries: epidemiological study

BACKGROUND

Studies of the impact of mental disorders on educational attainment are rare in both high-income and low- and middle-income (LAMI) countries.

AIMS

To examine the association between early-onset mental disorder and subsequent termination of education.

METHOD

Sixteen countries taking part in the World Health Organization World Mental Health Survey Initiative were surveyed with the Composite International Diagnostic Interview (n=41 688). Survival models were used to estimate associations between DSM-IV mental disorders and subsequent non-attainment of educational milestones.

RESULTS

In high-income countries, prior substance use disorders were associated with non-completion at all stages of education (OR 1.4-15.2). Anxiety disorders (OR=1.3), mood disorders (OR=1.4) and impulse control disorders (OR=2.2) were associated with early termination of secondary education. In LAMI countries, impulse control disorders (OR=1.3) and substance use disorders (OR=1.5) were associated with early termination of secondary education.

CONCLUSIONS

Onset of mental disorder and subsequent non-completion of education are consistently associated in both high-income and LAMI countries.

Depression and Type D personality represent different forms of distress in the Myocardial INfarction and Depression - Intervention Trial (MIND-IT)

BACKGROUND

We investigated whether depressive disorder and Type D personality refer to different forms of distress in the Myocardial INfarction and Depression - Intervention Trial (MIND-IT).

METHOD

A total of 1205 myocardial infarction (MI) patients were screened at 3, 6, 9 and 12 months post-MI; those with a Beck Depression Inventory (BDI) score 10 underwent the World Health Organization (WHO) Composite International Diagnostic Interview (CIDI). Patients completed the DS14 measure of Type D personality at 12 months and were stratified to one of four subgroups: depressed/Type D, depressed/non-Type D, non-depressed/Type D, or non-distressed.

RESULTS

Two hundred and six (17%) patients were diagnosed with depression and 224 (19%) with Type D. Only 7% (n=90) had both forms of distress, and 60% of Type D patients were free of depression in the first year post-MI. Type D moderated the relationship between depressive and cardiac disorder. Depressed patients without Type D had the worst clinical status (left ventricular dysfunction, heart failure, Killip class 2) as compared to other patients, whereas depressed patients with a Type D personality did not differ in clinical status from non-distressed patients. Contrasting 'pure' Type D and depression subgroups showed that Type D patients without depression were less likely to have left ventricular dysfunction [odds ratio (OR) 0.47, 95% confidence interval (CI) 0.35-0.65, p<0.0001] than depressed patients without Type D.

CONCLUSIONS

Depression and Type D refer to different forms of distress in post-MI patients; most Type D patients display non-psychiatric levels of distress and Type D moderates the relationship between depressive and cardiac disorder. Different depression/Type D subgroups may be involved in the prediction of cardiac prognosis.

Neuroticism, recall bias and attention bias for valenced probes: a twin study

BACKGROUND

Prior research on the nature of the vulnerability of neuroticism to psychopathology suggests biases in information processing towards emotional rather than neutral information. It is unclear to what extent this relationship can be explained by genetic or environmental factors.

METHOD

The genetic relationship between a neuroticism composite score and free recall of pleasant and unpleasant words and the reaction time on negative probes (dot-probe task) was investigated in 125 female twin pairs. Interaction effects were modelled to test whether the correlation between neuroticism and cognitive measures depended on the level of the neuroticism score.

RESULTS

The only significant correlation was between neuroticism and the proportion of recalled unpleasant words (heritability is 30%), and was only detectable at the higher end of the neuroticism distribution. This interaction effect seems to be due to environmental effects that make people in the same family more similar (e.g. parental discipline style), rather than genetic factors. An interesting sub-finding was that faster reaction times for left versus right visual field probes in the dot-probe task suggest that cognitive processing in the right hemisphere is more sensitive to subliminal (biologically relevant) cues and that this characteristic is under substantial genetic control (49%). Individual differences in reaction times on right visual field probes were due to environmental effects only.

CONCLUSIONS

There is no evidence that the predisposition of individuals to focus on negative (emotional) stimuli is a possible underlying genetic mechanism of neuroticism.

Mental-physical co-morbidity and its relationship with disability: results from the World Mental Health Surveys

BACKGROUND

The relationship between mental and physical disorders is well established, but there is less consensus as to the nature of their joint association with disability, in part because additive and interactive models of co-morbidity have not always been clearly differentiated in prior research.

METHOD

Eighteen general population surveys were carried out among adults as part of the World Mental Health (WMH) Survey Initiative (n=42 697). DSM-IV disorders were assessed using face-to-face interviews with the Composite International Diagnostic Interview (CIDI 3.0). Chronic physical conditions (arthritis, heart disease, respiratory disease, chronic back/neck pain, chronic headache, and diabetes) were ascertained using a standard checklist. Severe disability was defined as on or above the 90th percentile of the WMH version of the World Health Organization Disability Assessment Schedule (WHODAS-II).

RESULTS

The odds of severe disability among those with both mental disorder and each of the physical conditions (with the exception of heart disease) were significantly greater than the sum of the odds of the single conditions. The evidence for synergy was model dependent: it was observed in the additive interaction models but not in models assessing multiplicative interactions. Mental disorders were more likely to be associated with severe disability than were the chronic physical conditions.

CONCLUSIONS

This first cross-national study of the joint effect of mental and physical conditions on the probability of severe disability finds that co-morbidity exerts modest synergistic effects. Clinicians need to accord both mental and physical conditions equal priority, in order for co-morbidity to be adequately managed and disability reduced.

[Stress reactivity as an underlying mechanism of anxiety? Findings from the TRAILS study]

This short report provides an overview of the results of a recent Dutch study on the relation between anxiety and the reactivity of two important stress response systems: the autonomic nervous system and the hypothalamic-pituitary-adrenal axis. Future research will have to investigate the reactivity of both stress response systems in combination with several other important biological, psychological and social factors. In this way it should be possible to obtain more insight into the complex and interacting systems that underlie anxiety.

Mediators of the association between depression and role functioning

OBJECTIVE

While the adverse effect of Major Depressive Episode on role functioning is well established, the exact pathways remain unclear.

METHOD

Data from The European Study of the Epidemiology of Mental Disorders, a cross-sectional survey including 21 425 adults from six European countries, were used to assess 12-month depression (Composite International Diagnostic Interview), activity limitations and role functioning in the past 30 days (Disability Assessment Schedule). An a priori model based on the World Health Organization's International Classification of Functioning, Disability and Health was designed and a structural equation model for categorical and ordinal data was used (MPlus) to estimate the extent to which six limitations mediated the association between depression and role functioning.

RESULTS

The unadjusted association between depression and role functioning was strong (0.43; SE = 0.04). In the best-fitting model, only concentration and attention problems and embarrassment mediated a significant amount of association (direct effect dropped to 0.17; SE = 0.10, which was no longer significant).

CONCLUSIONS

Targeting cognition and embarrassment in treatment could help reduce depression-associated role disfunctioning.

The prevalence and effects of adult attention-deficit/hyperactivity disorder (ADHD) on the performance of workers: results from the WHO World Mental Health Survey Initiative

OBJECTIVES

To estimate the prevalence and workplace consequences of adult attention-deficit/hyperactivity disorder (ADHD).

METHODS

An ADHD screen was administered to 18-44-year-old respondents in 10 national surveys in the WHO World Mental Health (WMH) Survey Initiative (n = 7075 in paid or self-employment; response rate 45.9-87.7% across countries). Blinded clinical reappraisal interviews were administered in the USA to calibrate the screen. Days out of role were measured using the WHO Disability Assessment Schedule (WHO-DAS). Questions were also asked about ADHD treatment.

RESULTS

An average of 3.5% of workers in the 10 countries were estimated to meet DSM-IV criteria for adult ADHD (inter-quartile range: 1.3-4.9%). ADHD was more common among males than females and less common among professionals than other workers. ADHD was associated with a statistically significant 22.1 annual days of excess lost role performance compared to otherwise similar respondents without ADHD. No difference in the magnitude of this effect was found by occupation, education, age, gender or partner status. This effect was most pronounced in Colombia, Italy, Lebanon and the USA. Although only a small minority of workers with ADHD ever received treatment for this condition, higher proportions were treated for comorbid mental/substance disorders.

CONCLUSIONS

ADHD is a relatively common condition among working people in the countries studied and is associated with high work impairment in these countries. This impairment, in conjunction with the low treatment rate and the availability of cost-effective therapies, suggests that ADHD would be a good candidate for targeted workplace screening and treatment programs.