The Netherlands Study of Depression and Anxiety (NESDA): rationale, objectives and methods

Work functioning in persons with depressive and anxiety disorders: the role of specific psychopathological characteristics

BACKGROUND

Depressive and anxiety disorders affect work functioning and cause high labour costs.

AIMS

To examine and compare psychopathological characteristics of depressive and anxiety disorders in their effect on work functioning.

METHOD

In 1876 working participants of the Netherlands Study of Depression and Anxiety (NESDA) associations of presence, severity, comorbidity, duration and type of DSM-IV anxiety and depressive disorders with both absenteeism (<2 weeks and >2 weeks) and work performance (reduced and impaired) were assessed.

RESULTS

People with current depressive disorders had 7.10 times greater odds for the risk of >2 weeks work-absence and 5.67 greater odds for the risk of impaired work performance, while persons with current anxiety disorders had 1.84 and 2.13 greater odds for the risk of >2 weeks absence and impaired work performance, respectively. Even when persons were recovered from depressive and anxiety disorders, they still had a higher risk of poor work functioning. Persons with comorbidity, chronic depressive disorder, a generalized anxiety disorder, and more severity of both anxiety and depressive disorder had higher odds for the risk of absenteeism and decreased work performance.

CONCLUSION

Anxiety disorders have significant negative impact on work functioning, although smaller than the effect of depressive disorders. Comorbidity, severity, type and duration of the disorder, differentiate the risk of poor work functioning.

Development and validation of a 30-item short adaptation of the Mood and Anxiety Symptoms Questionnaire (MASQ)

The original Mood and Anxiety Symptoms Questionnaire (MASQ) is a 90-item self-report, designed to measure the dimensions of Clark and Watson's tripartite model. We developed and validated a 30-item short adaptation of the MASQ: the MASQ-D30, which is more suitable for large-scale psychopathology research and has a clearer factor structure. The MASQ-D30 was developed through a process of item reduction and grouping of the appropriate subscales in a sample of 489 psychiatric outpatients, using a validated Dutch translation, based on the original English MASQ, as a starting point. Validation was done in two other large samples of 1461 and 2471 subjects, respectively, with an anxiety, somatoform and/or depression diagnosis or no psychiatric diagnosis. Psychometric properties were investigated and compared between the MASQ-D30 and the full (adapted) MASQ. A three-dimensional model (negative affect, positive affect and somatic arousal) was found to represent the data well, indicating good construct validity. The scales of the MASQ-D30 showed good internal consistency (all alphas>0.87) in patient samples. Correlations of the subscales with other instruments indicated acceptable convergent validity. Psychometric properties were similar for the MASQ-D30 and the full questionnaire. In conclusion, the MASQ-D30 is a valid instrument to assess dimensional aspects of depression and anxiety and can easily be implemented in psychopathology studies.

Depressive and anxiety disorders and risk of subclinical atherosclerosis Findings from the Netherlands Study of Depression and Anxiety (NESDA)

OBJECTIVE

Current evidence regarding the association between psychopathology and subclinical atherosclerosis show inconsistent results. The present study examined whether subclinical atherosclerosis was more prevalent in a large cohort of persons with depressive or anxiety disorders as compared to non-depressed and non-anxious controls.

METHODS

Baseline data from the Netherlands Study of Depression and Anxiety were used, including 2717 persons, free of clinical cardiovascular disease. Participants had a DSM-IV-based current or remitted depressive (major depressive disorder, dysthymia) or anxiety (social phobia, generalized anxiety disorder, panic disorder, agoraphobia) disorder (n=2115) or were healthy controls (n=602). Additional clinical characteristics (severity, duration, age of onset and medication) were assessed. Ankle-brachial index (ABI) was used as a measure of vascular risk and was categorized as low (<or=0.90) and mildly low ABI (0.90-1.11) indicating subclinical atherosclerosis, and high ABI (>1.40), which was previously designated as a cardiovascular risk factor, reflecting arterial stiffness and wall calcification.

RESULTS

As compared to normal controls, persons with current (i.e., past year) depressive, anxiety or comorbid depressive and anxiety disorders showed a two- to threefold increased odds of low ABI (OR=2.78, 95% CI=1.05-7.35; OR=3.14, 95% CI=1.25-7.85; OR=2.67, 95% CI=1.09-6.51, respectively). No associations were found with mildly low or high ABI. Also, we did not further find a differential role for symptoms severity, duration, age of onset, and use of psychotropic medication in the link between psychopathology and subclinical atherosclerosis.

CONCLUSION

Persons with current depressive or anxiety disorders were more likely to have subclinical atherosclerosis compared to healthy controls.

Stimulated gene expression profiles as a blood marker of major depressive disorder

BACKGROUND

Major depressive disorder (MDD) is a moderately heritable disorder with a high lifetime prevalence. At present, laboratory blood tests to support MDD diagnosis are not available.

METHODS

We used a classifier approach on blood gene expression profiles of a unique set of unmedicated subjects (MDD patients and control subjects) to select genes with expression predictive for disease status. To reveal blood gene expression changes related to major depressive disorder-disease, we applied a powerful ex vivo stimulus to the blood: incubation with lipopolysaccharide (LPS; 10 ng/mL blood).

RESULTS

Based on LPS-stimulated blood gene expression using whole-genome microarrays (primary cohort; 21 MDD patients, 21 healthy control subjects), we identified a set of genes (CAPRIN1, CLEC4A, KRT23, MLC1, PLSCR1, PROK2, ZBTB16) that serves as a molecular signature of MDD. These findings were validated using an independent quantitative polymerase chain reaction method (primary cohort, p = .007). The difference between depressive patients and control subjects was confirmed (p = .019) in a replication cohort of 13 MDD patients and 14 control subjects. The MDD signature score comprised expression levels of seven genes could discriminate depressive patients from control subjects with sensitivity of 76.9% and specificity of 71.8%.

CONCLUSIONS

We have shown for the first time that molecular analysis of stimulated blood cells can be used as an endophenotype for MDD diagnosis, which is a milestone in establishing biomarkers for neuropsychiatric disorders with moderate heritability in general. Our results may provide a new entry point for following and predicting treatment outcome, as well as prediction of severity and recurrence of major depressive disorder.

Metabolic syndrome abnormalities are associated with severity of anxiety and depression and with tricyclic antidepressant use

OBJECTIVE

The metabolic syndrome (MetSyn) predisposes to cardiovascular disease and diabetes mellitus. There might also be an association between the MetSyn and anxiety and depression, but its nature is unclear. We aimed to investigate whether diagnosis, symptom severity and antidepressant use are associated with the MetSyn.

METHOD

We addressed the odds for the MetSyn and its components among 1217 depressed and/or anxious subjects and 629 controls, and their associations with symptom severity and antidepressant use.

RESULTS

Symptom severity was positively associated with prevalence of the MetSyn, [adjusted odds ratio (OR) 2.21 for very severe depression: 95% confidence interval (CI): 1.06-4.64, P = 0.04], which could be attributed to abdominal obesity and dyslipidemia. Tricyclic antidepressant (TCA) use also increased odds for the MetSyn (OR 2.30, 95% CI: 1.21-4.36, P = 0.01), independent of depression severity.

CONCLUSION

The most severely depressed people and TCA users more often have the MetSyn, which is driven by abdominal adiposity and dyslipidemia.

Patient factors associated with guideline-concordant treatment of anxiety and depression in primary care

OBJECTIVE

To identify associations of patient characteristics (predisposing, enabling and need factors) with guideline-concordant care for anxiety and depression in primary care.

DESIGN

Analysis of data from the Netherlands Study of Depression and Anxiety (NESDA).

PARTICIPANTS

Seven hundred and twenty-one patients with a current anxiety or depressive disorder, recruited from 67 general practitioners (GPs), were included.

MEASURES

Diagnoses according to the Diagnostic and Statistic Manual of Mental Disorders, fourth edition (DSM-IV) were made using a structured and widely validated assessment. Socio-demographic and enabling characteristics, severity of symptoms, disability, (under treatment for) chronic somatic conditions, perceived need for care, beliefs and evaluations of care were measured by questionnaires. Actual care data were derived from electronic medical records. Criteria for guideline-concordant care were based on general practice guidelines, issued by the Dutch College of General Practitioners.

RESULTS

Two hundred and eighty-one (39%) patients received guideline-concordant care. High education level, accessibility of care, comorbidity of anxiety and depression, and severity and disability scores were positively associated with receiving guideline-concordant care in univariate analyses. In multivariate multi-level logistic regression models, significant associations with the clinical need factors disappeared. Positive evaluations of accessibility of care increased the chance (OR = 1.31; 95%-CI = 1.05-1.65; p = 0.02) of receiving guideline-concordant care, as well as perceiving any need for medication (OR = 2.99; 95%-CI = 1.84-4.85; p < 0.001), counseling (OR = 2.25; 95%-CI = 1.29-3.95; p = 0.005) or a referral (OR = 1.83; 95%-CI = 1.09-3.09; p = 0.02). A low educational level decreased the odds (OR = 0.33; 95%-CI = 0.11-0.98; p = 0.04) of receiving guideline-concordant care.

CONCLUSIONS

This study shows that education level, accessibility of care and patients' perceived needs for care are more strongly associated with the delivery of guideline-concordant care for anxiety or depression than clinical need factors. Initiatives to improve GPs' communication skills around mental health issues, and to improve recognition of people suffering from anxiety disorders, could increase the number of patients receiving treatment for depression and anxiety in primary care.

Disorder-specific automatic self-associations in depression and anxiety: results of The Netherlands Study of Depression and Anxiety

BACKGROUND

Cognitive theory points to the importance of negative self-schemas in the onset and maintenance of depression and anxiety disorders. Hereby, it is important to distinguish between automatic and explicit self-schemas, reflecting different cognitive-motivational systems. This study tested whether patients with a current major depression and/or anxiety disorder are characterized by automatic self-anxious and self-depressive associations and whether these associations are disorder specific.

METHOD

Patients (n=2329) and non-clinical controls (n=652) were tested as part of The Netherlands Study of Depression and Anxiety, a multi-center, longitudinal, cohort study with patients from different health care settings. Patient groups and non-clinical controls (18-65 years of age) were compared with regard to automatic self-anxious and self-depressive associations measured with the Implicit Association Test.

RESULTS

Individuals with an anxiety disorder showed enhanced self-anxious associations, whereas individuals with a depression showed enhanced self-depressive associations. Individuals with co-morbid disorders scored high on both automatic self-associations. Although remitted individuals showed weaker automatic self-associations than people with a current disorder, their automatic self-anxious/depressed associations were still significantly stronger than those of the control group. Importantly, automatic self-associations showed predictive validity for the severity of anxious and depressive symptoms over and above explicit self-beliefs.

CONCLUSIONS

This study represents the first evidence that automatic self-anxious and self-depressive associations are differentially involved in anxiety disorders and depression. This may help to explain the refractoriness of these disorders and points to the potential importance of automatic self-associations in the development of psychopathological symptoms.

Childhood life events and childhood trauma in adult patients with depressive, anxiety and comorbid disorders vs. controls

OBJECTIVE

To investigate the association between childhood life events, childhood trauma and the presence of anxiety, depressive or comorbid anxiety and depressive disorders in adulthood.

METHOD

Data are from 1931 adult participants in the Netherlands Study of Depression and Anxiety (NESDA). Childhood life events included divorce of parents, early parental loss and 'placed in care', whereas childhood trauma was assessed as experienced emotional neglect, psychological, physical and sexual abuse prior to age 16.

RESULTS

Childhood life events were not associated with psychopathology, except for 'placed in care' in the comorbid group. All types of childhood trauma were increasingly prevalent in the following order: controls, anxiety, depression, and comorbid group (P < 0.001). The higher the score was on the childhood trauma index, the stronger the association with psychopathology (P < 0.001).

CONCLUSION

Childhood trauma rather than childhood life events are related to anxiety and depressive disorders. The strong associations with the comorbid group suggest that childhood trauma contributes to the severity of psychopathology. Our study underscores the importance of heightened awareness of the possible presence of childhood trauma, especially in adult patients with comorbid anxiety and depressive disorders.

A genomewide association study of nicotine and alcohol dependence in Australian and Dutch populations

Persistent tobacco use and excessive alcohol consumption are major public health concerns worldwide. Both alcohol and nicotine dependence (AD, ND) are genetically influenced complex disorders that exhibit a high degree of comorbidity. To identify gene variants contributing to one or both of these addictions, we first conducted a pooling-based genomewide association study (GWAS) in an Australian population, using Illumina Infinium 1M arrays. Allele frequency differences were compared between pooled DNA from case and control groups for: (1) AD, 1224 cases and 1162 controls; (2) ND, 1273 cases and 1113 controls; and (3) comorbid AD and ND, 599 cases and 488 controls. Secondly, we carried out a GWAS in independent samples from the Netherlands for AD and for ND. Thirdly, we performed a meta-analysis of the 10,000 most significant AD- and ND-related SNPs from the Australian and Dutch samples. In the Australian GWAS, one SNP achieved genomewide significance (p < 5 x 10(-8)) for ND (rs964170 in ARHGAP10 on chromosome 4, p = 4.43 x 10(-8)) and three others for comorbid AD/ND (rs7530302 near MARK1 on chromosome 1 (p = 1.90 x 10(-9)), rs1784300 near DDX6 on chromosome 11 (p = 2.60 x 10(-9)) and rs12882384 in KIAA1409 on chromosome 14 (p = 4.86 x 10(-8))). None of the SNPs achieved genomewide significance in the Australian/Dutch meta-analysis, but a gene network diagram based on the top-results revealed overrepresentation of genes coding for ion-channels and cell adhesion molecules. Further studies will be required before the detailed causes of comorbidity between AD and ND are understood.

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.

Increased sympathetic and decreased parasympathetic activity rather than changes in hypothalamic-pituitary-adrenal axis activity is associated with metabolic abnormalities

CONTEXT

Stress is suggested to lead to metabolic dysregulations as clustered in the metabolic syndrome, but the underlying biological mechanisms are not yet well understood.

OBJECTIVE

We examined the relationship between two main str systems, the autonomic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis, with the metabolic syndrome and its components.

DESIGN

The design was baseline data (yr 2004-2007) of a prospective cohort: the Netherlands Study of Depression and Anxiety (NESDA).

SETTING

The study comprised general community, primary care, and specialized mental health care.

PARTICIPANTS

This study included 1883 participants aged 18-65 yr.

MAIN OUTCOME MEASURES

Autonomic nervous system measures included heart rate, respiratory sinus arrhythmia (RSA; high RSA reflecting high parasympathetic activity), and preejection period (PEP; high PEP reflecting low sympathetic activity). HPA axis measures included the cortisol awakening response, evening cortisol, and a 0.5 mg dexamethasone suppression test as measured in saliva. Metabolic syndrome was based on the updated Adult Treatment Panel III criteria and included high waist circumference, serum triglycerides, blood pressure, serum glucose, and low high-density lipoprotein cholesterol.

RESULTS

RSA and PEP were both independently negatively associated with the presence of the metabolic syndrome, the number of metabolic dysregulations as well as all individual components except high-density lipoprotein cholesterol (all P < 0.02). Heart rate was positively related to the metabolic syndrome, the number of metabolic dysregulations, and all individual components (all P < 0.001). HPA axis measures were not related to metabolic syndrome or its components.

CONCLUSION

Our findings suggest that increased sympathetic and decreased parasympathetic nervous system activity is associated with metabolic syndrome, whereas HPA axis activity is not.

Salivary cortisol levels in persons with and without different anxiety disorders

OBJECTIVE

To examine the association between several subtypes of anxiety disorders and various cortisol indicators in a large cohort study. Anxiety disorders have been suggested to be linked to hypothalamic-pituitary-adrenal (HPA) axis activity, although results are scarce and inconsistent. No earlier studies have examined consistency of HPA axis findings across several anxiety subtypes and whether associations are state or trait dependent.

METHODS

Data are derived from 1427 participants of the Netherlands Study of Depression and Anxiety. Three groups were compared: 342 control participants without psychiatric disorders; 311 persons with a remitted (no current) anxiety disorder (social phobia, generalized anxiety disorder, panic disorder); and 774 persons with a current anxiety disorder, as diagnosed using the Composite International Diagnostic Interview psychiatric interview. Cortisol levels were measured in seven saliva samples, determining the 1-hour cortisol awakening response, evening cortisol, and cortisol response after 0.5 mg of dexamethasone ingestion.

RESULTS

Current anxiety disorder was associated with higher awakening cortisol levels (p = .002). These findings were mainly present for patients with panic disorder with agoraphobia and anxious patients with comorbid depressive disorder. Remitted anxiety only showed a trend toward higher morning cortisol (p = .08). No associations were observed for anxiety status and evening cortisol level or cortisol suppression after dexamethasone.

CONCLUSIONS

This study showed a modest but significantly higher 1-hour cortisol awakening response among anxiety patients, which was driven by those with panic disorder with agoraphobia and those with comorbid depression.

Long-term benzodiazepine use and salivary cortisol: the Netherlands Study of Depression and Anxiety (NESDA)

BACKGROUND

As benzodiazepines (BZDs) have anxiolytic effects, it is expected that they influence the stress system. During short-term treatment, BZD use was found to suppress cortisol levels. However, little research has been done on the effects of long-term BZD administration on the hypothalamic-pituitary-adrenal (HPA) axis.

METHODS

The association between long-term BZD use and cortisol levels was investigated in subjects of the Netherlands Study of Depression and Anxiety with a lifetime diagnosis of anxiety or depression (n = 1531). The subjects were categorized as "daily BZD users" (n = 96), "infrequent BZD users" (n = 172), and "nonusers" (n = 1263). Possible associations between characteristics of BZD use (dose, duration, and dependence) and salivary cortisol levels were analyzed.

MAIN OUTCOME MEASURE

Subjects provided 7 saliva samples, from which 4 cortisol indicators were calculated: the cortisol awakening response, diurnal slope, evening cortisol, and cortisol suppression after ingestion of 0.5 mg of dexamethasone.

RESULTS

Daily users used BZDs for a median duration of 26.5 months and had a median daily dosage of 6.0 mg as measured in diazepam equivalents. Evening cortisol levels were significantly lower in daily users (P = 0.004; effect size: d = 0.24) and infrequent users (P = 0.04; effect size: d = 0.12) compared to nonusers. We did not find significant differences in the cortisol awakening response, diurnal slope, or in the dexamethasone suppression test.

CONCLUSIONS

Despite the finding of slightly lower evening cortisol levels in daily and infrequent BZD users compared to nonusers, results indicate that long-term BZD use is not convincingly associated with HPA axis alterations.

Cognitive reactivity: investigation of a potentially treatable marker of suicide risk in depression

BACKGROUND

Suicidal ideation is the most stable symptom of depression across episodes. This relative stability may be brought about by increased cognitive reactivity to sad mood (CR) during periods of remission. The idea is that a network of depressive cognitions, which include suicidal ideation, becomes strengthened with each episode of depression. Consequently, the whole network may be more easily re-activated, for instance by an episode of low mood. We examined the association between reactivity of suicidal cognitions during recovery and the presence of suicidal ideation and behavior during the previous depressive episode.

METHODS

In a case-control design, the CR profiles of recovered depressed participants with (N=355) and without (N=250) a history of suicidal ideation were compared. Structured clinical interviews were used to determine diagnoses and prior symptoms. Cognitive reactivity profile was measured with the Leiden Index of Depression Sensitivity-Revised (LEIDS-R).

RESULTS

Suicidal ideation during a depressive episode was associated with a distinct CR profile during remission: elevated hopelessness reactivity scores. This relationship between prior suicidality and current CR was independent of anxiety disorder comorbidity. Moreover, a history of suicide attempt(s) was also associated with a distinct CR profile. These individuals had both higher hopelessness reactivity and higher aggression reactivity than the non-suicidal and suicidal ideation groups.

LIMITATIONS

Symptoms during the previous depressive episode were assessed retrospectively.

CONCLUSIONS

This is the first study to show that CR may underlie the relative stability of suicidal symptoms independent of anxiety comorbidity and that suicidal ideation and suicidal behavior are associated with distinct patterns of CR. Since CR is a potentially treatable vulnerability marker of depression recurrence, this has important clinical implications.

The validity of the Dutch K10 and extended K10 screening scales for depressive and anxiety disorders

The aim of this study was to validate the Dutch version of the Kessler-10 (K10) as well as an extended version (EK10) in screening for depressive and anxiety disorders in primary care. Data are from 1607 participants (18 through 65 years, 68.8% female) of the Netherlands Study of Depression and Anxiety (NESDA), recruited from 65 general practitioners. Participants completed the K10, extended with five additional questions focusing on core anxiety symptoms, and were evaluated with the WHO Composite International Diagnostic Interview (CIDI lifetime version 2.1) to assess DSM-IV disorders (major depressive disorder, dysthymia, generalized anxiety disorder, social phobia, panic disorder, agoraphobia). Reliability (Cronbach's alpha) of the Dutch K10 was 0.94. Based on Receiver Operating Characteristics (ROC) analysis, the area under the curve (AUC) for the K10 for any depressive and/or anxiety disorder was found to be 0.87. The extended questions on the EK10 significantly improved the detection of anxiety disorders in particular. With a cut-off point of 20, the K10 reached a sensitivity of 0.80 and a specificity of 0.81 for any depressive and/or anxiety disorder. For the EK10, a cut-off point of 20 and/or at least one positive answer on the additional questions provided a sensitivity of 0.90 and a specificity of 0.75 for detecting any depressive and/or anxiety disorder. The Dutch version of the K10 is appropriate for screening depressive disorders in primary care, while the EK10 is preferred in screening for both depressive and anxiety disorders.

Which physician and practice characteristics are associated with adherence to evidence-based guidelines for depressive and anxiety disorders?

BACKGROUND

Research on quality of care for depressive and anxiety disorders has reported low rates of adherence to evidence-based depression and anxiety guidelines. To improve this care, we need a better understanding of the factors determining guideline adherence.

OBJECTIVE

To investigate how practice- and professional-related factors are associated with adherence to these guidelines.

DESIGN

Cross-sectional cohort study.

PARTICIPANTS

A total of 665 patients with a composite interview diagnostic instrument diagnosis of depressive or anxiety disorders, and 62 general practitioners from 21 practices participated.

MEASURES

Actual care data were derived from electronic medical record data. The measurement of guideline adherence was based on performance indicators derived from evidence-based guidelines. Practice-, professional-, and patient-related characteristics were measured with questionnaires. The characteristics associated with guideline adherence were assessed by multivariate multilevel regression analysis.

RESULTS

A number of practice and professional characteristics showed a significant univariate association with guideline adherence. The multivariate multilevel analyses revealed that, after controlling for patient characteristics, higher rates of guideline adherence were associated with stronger confidence in depression identification, less perceived time limitations, and less perceived barriers for guideline implementation. These professional-related determinants differed among the overall concept of guideline adherence and the various treatment options.

CONCLUSIONS

This study showed that rates of adherence to guidelines on depressive and anxiety disorders were not associated with practice characteristics, but to some extent with physician characteristics. Although most of the identified professional-related determinants are very difficult to change, our results give some directions for improving depression and anxiety care.

Migraine symptomatology and major depressive disorder

Introduction and objective: Migraine and major depressive disorder (MDD) frequently co-occur, but it is unclear whether depression is associated with a specific subtype of migraine. The objective of this study was to investigate whether migraine is qualitatively different in MDD patients ( N = 1816) and non-depressed controls ( N = 3428).

Methods: Migraine symptom data were analyzed using multi-group Latent Class Analysis, and a qualitative comparison was made between the symptom profiles of MDD patients and controls, while allowing for differences in migraine prevalence and severity between groups.

Results: In both groups, three migrainous headache classes were identified, which differed primarily in terms of severity. Both mild and severe migrainous headaches were two to three times more prevalent in MDD patients. Migraine symptom profiles showed only minor qualitative differences in the MDD and non-MDD groups: in the severe migrainous headache class, significant differences were observed only in the prevalence of aggravation by physical activity (83% and 91% for the non-MDD and MDD groups, respectively) and aura (42% vs. 53%, respectively).

Conclusion: The similar overall symptom profiles observed in the MDD and non-MDD subjects suggest that a similar disease process may underlie migraine in both groups.

A Genomewide Association Study of Nicotine and Alcohol Dependence in Australian and Dutch Populations

Persistent tobacco use and excessive alcohol consumption are major public health concerns worldwide. Both alcohol and nicotine dependence (AD, ND) are genetically influenced complex disorders that exhibit a high degree of comorbidity. To identify gene variants contributing to one or both of these addictions, we first conducted a pooling-based genomewide association study (GWAS) in an Australian population, using Illumina Infinium 1M arrays. Allele frequency differences were compared between pooled DNA from case and control groups for: (1) AD, 1224 cases and 1162 controls; (2) ND, 1273 cases and 1113 controls; and (3) comorbid AD and ND, 599 cases and 488 controls. Secondly, we carried out a GWAS in independent samples from the Netherlands for AD and for ND. Thirdly, we performed a meta-analysis of the 10, 000 most significant AD- and ND-related SNPs from the Australian and Dutch samples. In the Australian GWAS, one SNP achieved genomewide significance (p < 5 x 10-8) for ND (rs964170 in ARHGAPlOon chromosome 4, p = 4.43 x 10”8) and three others for comorbid AD/ND (rs7530302 near MARK1 on chromosome 1 (p = 1.90 x 10-9), rs1784300 near DDX6 on chromosome 11 (p = 2.60 x 10-9) and rs12882384 in KIAA1409 on chromosome 14 (p = 4.86 x 10-8)). None of the SNPs achieved genomewide significance in the Australian/Dutch meta-analysis, but a gene network diagram based on the top-results revealed overrepre-sentation of genes coding for ion-channels and cell adhesion molecules. Further studies will be requirec before the detailed causes of comorbidity between AC and ND are understood.

Primary care patients with anxiety and depression: need for care from the patient's perspective

BACKGROUND

Many anxiety and depression patients receive no care, resulting in unnecessary suffering and high costs. Specific beliefs and the absence of a perceived need for care are major reasons for not receiving care. This study aims to determine the specific perceived need for care in primary care patients with anxiety and depression, and examine to what extent these different needs are met.

METHODS

Cross-sectional data were derived from The Netherlands Study of Depression and Anxiety (NESDA). In 622 primary care patients with a current (6-month recency) diagnosis of depression and/or anxiety disorder who recognised their mental health problem themselves, the perceived need for mental health care was measured by the Perceived Need for Care Questionnaire (PNCQ). Possible determinants were measured in the same interview by means of a questionnaire.

RESULTS

Most patients with anxiety or depression expressed a need for counselling or information. Medication, practical support, skills training and a referral were less often perceived to be needed. Multiple logistic regression analyses revealed that after controlling for age, clinical status and disability, patients' confidence in professional help and their evaluation of received care positively influenced their perception of a need for medication and counselling.

CONCLUSIONS

Although no conclusions can be made about what type of care was specifically not wanted, patients with anxiety or depression mostly want to receive information and counselling. Health professionals should be aware of the fact that there are differences in perceived need for care between subgroups of patients, based on their beliefs and their evaluation of care.

Screening for depression and anxiety: correlates of non-response and cohort attrition in the Netherlands study of depression and anxiety (NESDA)

A major problem in the analysis of attrition of cohorts in studies on mental health problems is that data on those who do not participate at the outset of a study are largely unavailable. It is not known how underlying psychopathology affects the first stages of screening where non-response and selectivity are usually highest. This article presents results of one of the centres of the Netherlands Study of Depression and Anxiety (NESDA), a longitudinal study aimed at describing the long-term course and consequences of depression and anxiety disorders. The aim is to describe the different ways of attrition during the first NESDA-wave in a cohort of patients aged 18-65 years of the Registration Network Groningen and to analyse whether attrition is related to gender, age and psychopathology as recorded in general practice. The attrition of the study cohort (n = 8475) was highest during the first stages, eventually leading to a population of 169 patients only who participated in the full NESDA-programme. Probabilities of transition from one stage of the screening process to the next were regressed on selected background variables using binary logistic regression. Correlates of participation were being female and being older (>40). Psychopathology was an important variable in the formation of the initial sample cohort, but only had a weak influence on patient response to the screening questionnaire. Study design factors had a stronger impact on the changing composition of the cohort at each screening stage compared to patient factors.

Assessing salivary cortisol in large-scale, epidemiological research

Salivary cortisol measures are increasingly being incorporated into large-scale, population-based, or epidemiological research, in which participants are selected to be representative of particular communities or populations of interest, and sample sizes are in the order of hundreds to tens of thousands of participants. These approaches to studying salivary cortisol provide important advantages but pose a set of challenges. The representative nature of sampling, and large samples sizes associated with population-based research offer high generalizability and power, and the ability to examine cortisol functioning in relation to: (a) a wide range of social environments; (b) a diverse array individuals and groups; and (c) a broad set of pre-disease and disease outcomes. The greater importance of high response rates (to maintain generalizability) and higher costs associated with this type of large-scale research, however, requires special adaptations of existing ambulatory cortisol protocols. These include: using the most efficient sample collection protocol possible that still adequately address the specific cortisol-related questions at hand, and ensuring the highest possible response and compliance rates among those individuals invited to participate. Examples of choices made, response rates obtained, and examples of results obtained from existing epidemiological cortisol studies are offered, as are suggestions for the modeling and interpretation of salivary cortisol data obtained in large-scale epidemiological research.

Collaborative stepped care for anxiety disorders in primary care: aims and design of a randomized controlled trial

BACKGROUND

Panic disorder (PD) and generalized anxiety disorder (GAD) are two of the most disabling and costly anxiety disorders seen in primary care. However, treatment quality of these disorders in primary care generally falls beneath the standard of international guidelines. Collaborative stepped care is recommended for improving treatment of anxiety disorders, but cost-effectiveness of such an intervention has not yet been assessed in primary care. This article describes the aims and design of a study that is currently underway. The aim of this study is to evaluate effects and costs of a collaborative stepped care approach in the primary care setting for patients with PD and GAD compared with care as usual.

METHODS/DESIGN

The study is a two armed, cluster randomized controlled trial. Care managers and their primary care practices will be randomized to deliver either collaborative stepped care (CSC) or care as usual (CAU). In the CSC group a general practitioner, care manager and psychiatrist work together in a collaborative care framework. Stepped care is provided in three steps: 1) guided self-help, 2) cognitive behavioral therapy and 3) antidepressant medication. Primary care patients with a DSM-IV diagnosis of PD and/or GAD will be included. 134 completers are needed to attain sufficient power to show a clinically significant effect of 1/2 SD on the primary outcome measure, the Beck Anxiety Inventory (BAI). Data on anxiety symptoms, mental and physical health, quality of life, health resource use and productivity will be collected at baseline and after three, six, nine and twelve months.

DISCUSSION

It is hypothesized that the collaborative stepped care intervention will be more cost-effective than care as usual. The pragmatic design of this study will enable the researchers to evaluate what is possible in real clinical practice, rather than under ideal circumstances. Many requirements for a high quality trial are being met. Results of this study will contribute to treatment options for GAD and PD in the primary care setting. Results will become available in 2011.

TRIAL REGISTRATION

NTR1071.

Adherence to evidence-based guidelines for depression and anxiety disorders is associated with recording of the diagnosis

OBJECTIVES

To assess professionals' adherence to evidence-based guidelines and to investigate whether or not this is influenced by recording of the diagnosis and symptom severity.

METHOD

Analysis of baseline cross-sectional data of a cohort study of 721 primary care patients with a confirmed diagnosis of a depressive or anxiety disorder. Information on the management of depressive and anxiety disorders was gathered from the electronic medical patient records. Guideline adherence was measured by an algorithm, based on performance indicators.

RESULTS

Forty-two percent of the patients with a depressive disorder was treated in accordance with the guideline, whereas 27% of the patients with an anxiety disorder received guideline-consistent care. The provision of care in line with current depression and anxiety guidelines was around 50% for persons with both types of disorders. Documentation of an International Classification of Primary Care diagnosis of depression or anxiety disorder appeared to have a strong influence on guideline adherence. Symptom severity, however, did not influence guideline adherence.

CONCLUSIONS

Adherence to depression and anxiety guidelines can be improved, even when the general practitioner makes the diagnosis and records it. Data on actual health care delivery and quality of care provide insight and may be useful in developing quality improvement activities.

The role of personality in comorbidity among anxiety and depressive disorders in primary care and specialty care: a cross-sectional analysis

OBJECTIVE

Almost no cross-sectional studies directly compared the rate and pattern of comorbidity of affective disorders in relation to personality traits of patients seen in primary care versus specialty mental health care.

METHOD

Using data from the Netherlands Study of Depression and Anxiety, we compared 1086 primary care patients with 790 consecutive specialized mental health care patients. All participants had at least one lifetime Diagnostic and Statistical Manual for Mental Disorders, Fourth Edition-based diagnosis of depression or anxiety. Personality was assessed with the NEO Five-Factor Inventory.

RESULTS

In both settings it was common to have at least one lifetime comorbid affective disorder. Compared to primary care patients, specialty care patients showed elevated scores for Neuroticism and lower scores for Extraversion and Conscientiousness. The odds of having another disorder given any one disorder was no longer significant after accounting for personality dimensions. Only Neuroticism proved to be positively associated with comorbidity per se.

CONCLUSIONS

Prevalence of and comorbidity among anxiety and depressive disorders in primary care were very similar to those in specialty care. Neuroticism - but no other personality traits - may help to understand the comorbidity among anxiety and depressive disorders irrespective of recruitment setting.

Associations between sociodemographic, sampling and health factors and various salivary cortisol indicators in a large sample without psychopathology

BACKGROUND

Cortisol levels are increasingly often assessed in large-scale psychosomatic research. Although determinants of different salivary cortisol indicators have been described, they have not yet been systematically studied within the same study with a large sample size. Sociodemographic, health and sampling-related determinants of salivary cortisol levels were examined in a sample without potential disturbances because of psychopathology.

METHODS

Using 491 respondents (mean age=43.0 years, 59.5% female) without lifetime psychiatric disorders from the Netherlands Study of Depression and Anxiety (NESDA), sociodemographic, sampling and health determinants of salivary cortisol levels were examined. Respondents collected seven salivary cortisol samples providing information about 1-h awakening cortisol, diurnal slope, evening cortisol and a dexamethasone (0.5mg) suppression test (DST).

RESULTS

Higher overall morning cortisol values were found for smokers, physically active persons, persons without cardiovascular disease, sampling on a working day or in a month with less daylight. In addition, the cortisol awakening response was significantly flattened for males, persons with cardiovascular disease, those with late awakening times and those with longer sleep duration. Diurnal slope was steeper in men, physically active persons, late awakeners, working persons, and season with less daylight. A higher evening cortisol level was associated with older age, smoking and season with more daylight. Cortisol suppression after dexamethasone ingestion was found to be less pronounced in smokers, less active persons and sampling on a weekday.

CONCLUSION

Sociodemographic variables (sex, age), sampling factors (awakening time, working day, sampling month, sleep duration) and health indicators (smoking, physical activity, cardiovascular disease) were shown to influence different features of salivary cortisol levels. Smoking had the most consistent effect on all cortisol variables. These factors should be considered in psychoneuroendocrinology research.

Do Automatic Self-Associations Relate to Suicidal Ideation?

Dysfunctional self-schemas are assumed to play an important role in suicidal ideation. According to recent information-processing models, it is important to differentiate between ‘explicit’ beliefs and automatic associations. Explicit beliefs stem from the weighting of propositions and their corresponding ‘truth’ values, while automatic associations reflect more simple associations in memory. Both types of associations are assumed to have different functional properties and both may be involved in suicidal ideation. Thus far, studies into self-schemas and suicidal ideation focused on the more explicit, consciously accessible traces of self-schemas and predominantly relied on self-report questionnaires or interviews. To complement these ‘explicit’ findings and more directly tap into self-schemas, this study investigated automatic self-associations in a large scale community sample that was part of the Netherlands Study of Depression and Anxiety (NESDA). The results showed that automatic self-associations of depression and anxiety were indeed significantly related to suicidal ideation and past suicide attempt. Moreover, the interactions between automatic self-depressive (anxious) associations and explicit self-depressive (anxious) beliefs explained additional variance over and above explicit self-beliefs. Together these results provide an initial insight into one explanation of why suicidal patients might report difficulties in preventing and managing suicidal thoughts.

Neuroticism modulates amygdala-prefrontal connectivity in response to negative emotional facial expressions

Neuroticism is associated with the experience of negative affect and the development of affective disorders. While evidence exists for a modulatory role of neuroticism on task induced brain activity, it is unknown how neuroticism affects brain connectivity, especially the crucial coupling between the amygdala and the prefrontal cortex. Here we investigate this relation between functional connectivity and personality in response to negative facial expressions. Sixty healthy control participants, from the Netherlands Study on Depression and Anxiety (NESDA), were scanned during an emotional faces gender decision task. Activity and functional amygdala connectivity (psycho-physiological interaction [PPI]) related to faces of negative emotional valence (angry, fearful and sad) was compared to neutral facial expressions, while neuroticism scores were entered as a regressor. Activity for fearful compared to neutral faces in the dorsomedial prefrontal (dmPFC) cortex was positively correlated with neuroticism scores. PPI analyses revealed that right amygdala-dmPFC connectivity for angry and fearful compared to neutral faces was positively correlated with neuroticism scores. In contrast, left amygdala-anterior cingulate cortex (ACC) connectivity for angry, fearful and sad compared to neutral faces was negatively related to neuroticism levels. DmPFC activity has frequently been associated with self-referential processing in social cognitive tasks. Our results therefore suggest that high neurotic participants display stronger self-referential processing in response to negative emotional faces. Second, in line with previous reports on ACC function, the negative correlation between amygdala-ACC connectivity and neuroticism scores might indicate that those high in neuroticism display diminished control function of the ACC over the amygdala. These connectivity patterns might be associated with vulnerability to developing affective disorders such as depression and anxiety.

A genome-wide association study of northwestern Europeans involves the C-type natriuretic peptide signaling pathway in the etiology of human height variation

Northwestern Europeans are among the tallest of human populations. The increase in body height in these people appears to have reached a plateau, suggesting the ubiquitous presence of an optimal environment in which genetic factors may have exerted a particularly strong influence on human growth. Therefore, we performed a genome-wide association study (GWAS) of body height using 2.2 million markers in 10 074 individuals from three Dutch and one German population-based cohorts. Upon genotyping, the 12 most significantly height-associated single nucleotide polymorphisms (SNPs) from this GWAS in 6912 additional individuals of Dutch and Swedish origin, a genetic variant (rs6717918) on chromosome 2q37.1 was found to be associated with height at a genome-wide significance level (P_combined = 3.4 × 10⁻⁹). Notably, a second SNP (rs6718438) located ∼450 bp away and in strong LD (r² = 0.77) with rs6717918 was previously found to be suggestive of a height association in 29 820 individuals of mainly northwestern European ancestry, and the over-expression of a nearby natriuretic peptide precursor type C (NPPC) gene, has been associated with overgrowth and skeletal anomalies. We also found a SNP (rs10472828) located on 5p14 near the natriuretic peptide receptor 3 (NPR3) gene, encoding a receptor of the NPPC ligand, to be associated with body height (P_combined = 2.1 × 10⁻⁷). Taken together, these results suggest that variation in the C-type natriuretic peptide signaling pathway, involving the NPPC and NPR3 genes, plays an important role in determining human body height.

Hierarchical functional modularity in the resting-state human brain

Functional magnetic resonance imaging (fMRI) studies have shown that anatomically distinct brain regions are functionally connected during the resting state. Basic topological properties in the brain functional connectivity (BFC) map have highlighted the BFC's small-world topology. Modularity, a more advanced topological property, has been hypothesized to be evolutionary advantageous, contributing to adaptive aspects of anatomical and functional brain connectivity. However, current definitions of modularity for complex networks focus on nonoverlapping clusters, and are seriously limited by disregarding inclusive relationships. Therefore, BFC's modularity has been mainly qualitatively investigated. Here, we introduce a new definition of modularity, based on a recently improved clustering measurement, which overcomes limitations of previous definitions, and apply it to the study of BFC in resting state fMRI of 53 healthy subjects. Results show hierarchical functional modularity in the brain.

Association between anxiety disorders and heart rate variability in The Netherlands Study of Depression and Anxiety (NESDA)

OBJECTIVE

To determine whether patients with different types of anxiety disorder (panic disorder, social phobia, generalized anxiety disorder) have higher heart rate and lower heart rate variability compared with healthy controls in a sample that was sufficiently powered to examine the confounding effects of lifestyle and antidepressants.

METHODS

The standard deviation of the normal-to-normal intervals (SDNN), heart rate (HR), and respiratory sinus arrhythmia (RSA) were measured in 2059 subjects (mean age = 41.7 years, 66.8% female) participating in The Netherlands Study of Depression and Anxiety (NESDA). Based on the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) and Composite International Diagnostic Interview (CIDI), NESDA participants were classified as healthy controls (n = 616), subjects with an anxiety diagnosis earlier in life (n = 420), and subjects with current anxiety diagnosis (n = 1059).

RESULTS

Current anxious subjects had a significantly lower SDNN and RSA compared with controls. RSA was also significantly lower in remitted anxious subjects compared with controls. These associations were similar across the three different types of anxiety disorders. Adjustment for lifestyle had little impact. However, additional adjustment for antidepressant use reduced all significant associations between anxiety and HRV to nonsignificant. Anxious subjects who used a tricyclic antidepressant, a selective serotonin reuptake inhibitor, or another antidepressant showed significantly lower mean SDNN and RSA compared with controls (effect sizes = 0.20-0.80 for SDNN and 0.42-0.79 for RSA). Nonmedicated anxious subjects did not differ from controls in mean SDNN and RSA.

CONCLUSION

This study shows that anxiety disorders are associated with significantly lower HR variability, but the association seems to be driven by the effects of antidepressants.

Genome-wide association for major depressive disorder: a possible role for the presynaptic protein piccolo

Major depressive disorder (MDD) is a common complex trait with enormous public health significance. As part of the Genetic Association Information Network initiative of the US Foundation for the National Institutes of Health, we conducted a genome-wide association study of 435 291 single nucleotide polymorphisms (SNPs) genotyped in 1738 MDD cases and 1802 controls selected to be at low liability for MDD. Of the top 200, 11 signals localized to a 167 kb region overlapping the gene piccolo (PCLO, whose protein product localizes to the cytomatrix of the presynaptic active zone and is important in monoaminergic neurotransmission in the brain) with P-values of 7.7 x 10(-7) for rs2715148 and 1.2 x 10(-6) for rs2522833. We undertook replication of SNPs in this region in five independent samples (6079 MDD independent cases and 5893 controls) but no SNP exceeded the replication significance threshold when all replication samples were analyzed together. However, there was heterogeneity in the replication samples, and secondary analysis of the original sample with the sample of greatest similarity yielded P=6.4 x 10(-8) for the nonsynonymous SNP rs2522833 that gives rise to a serine to alanine substitution near a C2 calcium-binding domain of the PCLO protein. With the integrated replication effort, we present a specific hypothesis for further studies.

Genome-wide association study of smoking initiation and current smoking

For the identification of genes associated with smoking initiation and current smoking, genome-wide association analyses were carried out in 3497 subjects. Significant genes that replicated in three independent samples (n = 405, 5810, and 1648) were visualized into a biologically meaningful network showing cellular location and direct interaction of their proteins. Several interesting groups of proteins stood out, including glutamate receptors (e.g., GRIN2B, GRIN2A, GRIK2, GRM8), proteins involved in tyrosine kinase receptor signaling (e.g., NTRK2, GRB14), transporters (e.g., SLC1A2, SLC9A9) and cell-adhesion molecules (e.g., CDH23). We conclude that a network-based genome-wide association approach can identify genes influencing smoking behavior.

Depression is associated with decreased blood pressure, but antidepressant use increases the risk for hypertension

The present study compared blood pressure levels between subjects with clinical anxiety and depressive disorders with healthy controls. Cross-sectional data were obtained in a large cohort study, the Netherlands Study of Depression and Anxiety (N=2981). Participants were classified as controls (N=590) or currently or remittedly depressed or anxious subjects (N=2028), of which 1384 were not and 644 were using antidepressants. Regression analyses calculated the contributions of anxiety and depressive disorders and antidepressant use to diastolic and systolic blood pressures, after controlling for multiple covariates. Heart rate and heart rate variability measures were subsequently added to test whether effects of anxiety/depression or medication were mediated by vagal control over the heart. Higher mean diastolic blood pressure was found among the current anxious subjects (beta=0.932; P=0.03), although anxiety was not significantly related to hypertension risk. Remitted and current depressed subjects had a lower mean systolic blood pressure (beta=-1.74, P=0.04 and beta=-2.35, P=0.004, respectively) and were significantly less likely to have isolated systolic hypertension than controls. Users of tricyclic antidepressants had higher mean systolic and diastolic blood pressures and were more likely to have hypertension stage 1 (odds ratio: 1.90; 95% CI: 0.94 to 3.84; P=0.07) and stage 2 (odds ratio: 3.19; 95% CI: 1.35 to 7.59; P=0.008). Users of noradrenergic and serotonergic working antidepressants were more likely to have hypertension stage 1. This study shows that depressive disorder is associated with low systolic blood pressure and less hypertension, whereas the use of certain antidepressants is associated with both high diastolic and systolic blood pressures and hypertension.

Receiving treatment for common mental disorders

OBJECTIVE

Anxiety and depressive disorders are widely prevalent, but patients are only treated in a minority of cases. In this study, the explanation of receiving mental health treatment is sought in predisposing and enabling characteristics and indicators for objective and self-perceived need.

METHODS

Cross-sectional analysis of data collected in the Netherlands Study of Depression and Anxiety (NESDA) among 743 persons with an anxiety and/or depression diagnosis as assessed by the CIDI. Receipt of mental health treatment was assessed in the face-to-face interview, as well as indicators of predisposing and enabling factors and variables evaluating need for care.

RESULTS

Of the total sample, 57% received treatment in the past 6 months in the general practice setting (50%) or the mental health care setting (14%). Younger patients, patients who evaluated their providers better on communicative abilities and patients who perceived mental health problems themselves had greater odds of having professional mental health contacts in the primary care setting. Confidence in professional help and higher severity of mental problems were associated with greater odds of having specialized mental health care.

CONCLUSION

Receiving help for common mental disorders depends not only on the objective need of the patient but also at least as much on the patients' own recognition that their problems have a mental health origin. Furthermore, in primary care especially, the patients' judgment of their providers' affective abilities may be decisive for being treated. For receiving specialized care, patients are also directed by their confidence in professional help.