Development of a simple standardized scoring system for assessing large vessel vasculitis by 18F-FDG PET-CT and differentiation from atherosclerosis

PURPOSE

This study is to develop a structured approach to distinguishing large-artery vasculitis from atherosclerosis using 18-fluorodeoxyglucose positron emission tomography combined with low-dose computed tomography (FDG PET/CT).

METHODS

FDG PET/CT images of 60 patients were evaluated, 30 having biopsy-proven giant cell arteritis (GCA; the most common form of large-artery vasculitis), and 30 with severe atherosclerosis. Images were evaluated by 12 nuclear medicine physicians using 5 criteria: FDG uptake pattern (intensity, distribution, circularity), the degree of calcification, and co-localization of calcifications with FDG-uptake. Criteria that passed agreement, and reliability tests were subsequently analysed for accuracy using receiver operator curve (ROC) analyses. Criteria that showed discriminative ability were then combined in a multi-component scoring system. Both initial and final 'gestalt' conclusion were also reported by observers before and after detailed examination of the images.

RESULTS

Agreement and reliability analyses disqualified 3 of the 5 criteria, leaving only FDG uptake intensity compared to liver uptake and arterial wall calcification for potential use in a scoring system. ROC analysis showed an area under the curve (AUC) of 0.90 (95%CI 0.87-0.92) for FDG uptake intensity. Degree of calcification showed poor discriminative ability on its own (AUC of 0.62; 95%CI 0.58-0.66). When combining presence of calcification with FDG uptake intensity into a 6-tiered scoring system, the AUC remained similar at 0.91 (95%CI 0.88-0.93). After exclusion of cases with arterial prostheses, the AUC increased to 0.93 (95%CI 0.91-0.95). The accuracy of the 'gestalt' conclusion was initially 89% (95%CI 86-91%) and increased to 93% (95%CI 91-95%) after detailed image examination.

CONCLUSION

Standardised assessment of arterial wall FDG uptake intensity, preferably combined with assessment of arterial calcifications into a scoring method, enables accurate, but not perfect, distinction between large artery vasculitis and atherosclerosis.

Social cost-benefit analysis of regulatory policies to reduce alcohol use in The Netherlands

Background

If all costs and all benefits of alcohol use are expressed in monetary terms, the net costs were 2,3 to 4,2 billion euro in 2013. Examples of the costs of alcohol are less productivity at work, costs of police and justice and traffic accidents.

Methods

In this study three regulatory policies have been modelled using the Social Cost-Benefit Analysis (SCBA) approach. Regulatory policies aimed at curbing alcohol consumption were (1) an increase in excise taxes, (2) a reduction of the number of sales venues, and (3) a total mediaban for advertising alcohol.

Results

In the long run, over a period of 50 years, an increase in excise taxes of 50% will result in societal benefits of 4.5 to 10.7 billion euro, an increase of excise taxes of 200% will result in societal benefits of 12.2 to 35.8 billion euro. The societal benefits of closure of 10% of sales venues are estimated at 1.8 to 4.3 billion euro after 50 years, and at 4.6 to 10.7 billion euro when 25% of sales venues would be closed. The societal benefits of a mediaban would amount to 3.5 to 7.8 billion euro after 50 years, but this estimate is surrounded by uncertainty.

Conclusions

Regulatory policies aimed at reducing the amount of alcohol consumed, such as a further increase of excise taxes, a reduction of the number of sales venues and a total mediaban, will result in savings for society at large. However, costs and benefits are spread unequally over the different stakeholders.

Social cost-benefit analysis of tobacco control policies in the Netherlands

Background

In the Netherlands approximately 23% of the population of 15 years and older smokes. The main research questions were to identify what social costs- and benefits can be expected when various tobacco control policies would be implemented in The Netherlands, how do costs and benefits change over time, and which sectors in society could expect to incur costs and in which sectors accrue profits.

Methods

A SCBA was conducted using a combination of the Chronic Disease Model developed by the National Institute for Public Health and the Environment (RIVM), the SimSmoke model and a specially designed excel model. Policies included both tax increases (i.e. increase of excise tax on tobacco of 5% or 10% each year) and a policy package as proposed by the World Health Organization (i.e. including mass media campaigns and mediabans).

Results

When no new policy measures are implemented, the prevalence of smoking will decrease by 2.3 percentage points over the next 35 years. The policies reviewed in this report have the potential to decrease smoking prevalence by 14.2 percentage points (and in a ‘smoking-free society scenario, by as much as 17.4 percentage points). Furthermore, the results show that the intervention costs for all scenarios are minimal, and that investing in health is beneficial as seen from both the public health and fiscal perspective.

Conclusions

This study demonstrated that reducing the prevalence of smoking has beneficial effects for various stakeholders within the Dutch society: such as employers (e.g. increased productivity) and consumers (e.g. increase quality of life).

Freehand-SPECT with 99mTc-HDP as tool to guide percutaneous biopsy of skeletal lesions detected on bone scintigraphy

PURPOSE

To assess the feasibility of using freehand Single Photon Emission Computed Tomography (freehandSPECT) for the identification of technetium-99m-hydroxydiphosphonate (^99mTc-HDP) positive bone lesions and to evaluate the possibility of using these imaging data-sets for augmented- and virtual-reality based navigation approaches.

MATERIAL AND METHODS

In 20 consecutive patients referred for scintigraphy with ^99mTc-HDP, 21 three-dimensional freehandSPECT-images were generated using a handheld gamma camera. Concordance of the two different data sets was ranked. Furthermore, feasibility of segmenting the hotspot of tracer accumulation for navigation purposes was assessed.

RESULTS

In 86% of the cases freehandSPECT images showed good concordance with the corresponding part of the scintigraphic images. In lesions with a signal to background ratio (SBR) >1.36, freehandSPECT provided an automatically segmented reference point for navigation purposes. In 14% of the cases (average SBR 1.82, range 1.0-3.4) freehandSPECT images showed intermediate concordance due to difficult anatomical area or negative bone scintigraphy and could not be used as navigation targets.

CONCLUSION

In this pilot study, in 86% of the cases freehandSPECT demonstrated good concordance with traditional scintigraphy. A lesion with a SBR of 1.36 or more was suitable for navigation. These high-quality freehandSPECT images supported the future exploration navigation strategies, e.g. guided needle biopsies.

Value and potential limitations of vertebral fracture assessment (VFA) compared to conventional spine radiography: experience from a fracture liaison service (FLS) and a meta-analysis

We evaluated the value of VFA in the identification of vertebral fractures using a retrospective study and a meta-analysis. Performance of VFA was adequate in the meta-analysis although this was not demonstrated in our centre. We recommend checking the performance of VFA tools before exclusively relying on this tool.

INTRODUCTION

Vertebral fractures are traditionally diagnosed using conventional radiographs of the spine. Vertebral fracture assessment (VFA) has been advocated as an alternative tool in the diagnosis of these fractures.

METHODS

We conducted a retrospective study as well as a systematic review and a meta-analysis to evaluate the performance of VFA compared to conventional spinal radiography in patients who had sustained a fracture and thus at risk for osteoporosis. A risk of bias analysis was also performed.

RESULTS

The diagnostic study included 542 patients (25% male) with fractures. The sensitivity of low-radiation VFA to detect a patient with a vertebral fracture ≥ Genant grade 2 was 0.77 and its specificity 0.80. Two hundred ninety-seven (55%) patients had ≥1 and 135(25%) ≥3 unevaluable vertebrae. The systematic review identified 16 studies including a total of 3238 subjects (19% male) with a mean age range of 45 to 74 years. Seven studies had a low risk of bias and 9 had an intermediate risk, mainly due to not consecutively including patients. The pooled sensitivity of VFA to detect a patient with a vertebral fracture ≥Genant grade 2 was 0.84 (95% CI, 0.72-0.92) and specificity 0.90 (95% CI, 0.84-0.94).

CONCLUSIONS

Our findings from the meta-analysis suggest an adequate performance of VFA for the detection of vertebral fractures. However, we could not demonstrate these findings in our center, especially the specificity. Our data advocate caution with exclusively relying on VFA in the assessment of vertebral fractures without identifying performance and potential limitations of the technique.

Development of a stage-dependent prognostic model to predict psychosis in ultra-high-risk patients seeking treatment for co-morbid psychiatric disorders

BACKGROUND

Current ultra-high-risk (UHR) criteria appear insufficient to predict imminent onset of first-episode psychosis, as a meta-analysis showed that about 20% of patients have a psychotic outcome after 2 years. Therefore, we aimed to develop a stage-dependent predictive model in UHR individuals who were seeking help for co-morbid disorders.

METHOD

Baseline data on symptomatology, and environmental and psychological factors of 185 UHR patients (aged 14-35 years) participating in the Dutch Early Detection and Intervention Evaluation study were analysed with Cox proportional hazard analyses.

RESULTS

At 18 months, the overall transition rate was 17.3%. The final predictor model included five variables: observed blunted affect [hazard ratio (HR) 3.39, 95% confidence interval (CI) 1.56-7.35, p < 0.001], subjective complaints of impaired motor function (HR 5.88, 95% CI 1.21-6.10, p = 0.02), beliefs about social marginalization (HR 2.76, 95% CI 1.14-6.72, p = 0.03), decline in social functioning (HR 1.10, 95% CI 1.01-1.17, p = 0.03), and distress associated with suspiciousness (HR 1.02, 95% CI 1.00-1.03, p = 0.01). The positive predictive value of the model was 80.0%. The resulting prognostic index stratified the general risk into three risk classes with significantly different survival curves. In the highest risk class, transition to psychosis emerged on average ⩾8 months earlier than in the lowest risk class.

CONCLUSIONS

Predicting a first-episode psychosis in help-seeking UHR patients was improved using a stage-dependent prognostic model including negative psychotic symptoms (observed flattened affect, subjective impaired motor functioning), impaired social functioning and distress associated with suspiciousness. Treatment intensity may be stratified and personalized using the risk stratification.

[Prognostic modelling and proactive intervention in psychosis: efficacy and cost-effectiveness]

Diagnoses have heterogeneous outcomes, varying from good to extremely poor. There is a need to single out an ultra-high-risk group of individuals who have illnesses that might well end unfavourably or who might later develop serious psychopathology.<br/> AIM: To devise a screening instrument that can identify a group of individuals who run a very high risk of developing a first-episode psychosis, and to create a type of intervention that can modify the course of the illness.<br/> METHOD: We developed a short screening instrument (PQ-16) and were able to ascertain its predictive value. We also tested an intervention that could influence risk factors and deal with emerging symptoms thereby achieving a better outcome for the patient.<br/> RESULTS: We developed a two-step detection instrument with a positive predictive value of 44%. The intervention, involving cognitive behavioural therapy for ultra-high-risk patients, was effective and led to a risk reduction of about 50%. Using the ultra-high-risk group of patients, we were able to model three prognostic profiles, each carrying a 4%, 13%, and 70% risk of subsequently developing psychosis. The intervention was cost-effective, reducing the financial burden on the health care services and on society as a whole.<br/> CONCLUSION: Prognostic modelling and proactive intervention can achieve improvements in health at lower costs.

[Online self-help for persons with suicidal intentions: budget impact analysis]

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Metacognitive training for schizophrenia spectrum patients: a meta-analysis on outcome studies

BACKGROUND

Metacognitive training (MCT) for schizophrenia spectrum is widely implemented. It is timely to systematically review the literature and to conduct a meta-analysis.

METHOD

Eligible studies were selected from several sources (databases and expert suggestions). Criteria included comparative studies with a MCT condition measuring positive symptoms and/or delusions and/or data-gathering bias. Three meta-analyses were conducted on data gathering (three studies; 219 participants), delusions (seven studies; 500 participants) and positive symptoms (nine studies; 436 participants). Hedges' g is reported as the effect size of interest. Statistical power was sufficient to detect small to moderate effects.

RESULTS

All analyses yielded small non-significant effect sizes (0.26 for positive symptoms; 0.22 for delusions; 0.31 for data-gathering bias). Corrections for publication bias further reduced the effect sizes to 0.21 for positive symptoms and to 0.03 for delusions. In blinded studies, the corrected effect sizes were 0.22 for positive symptoms and 0.03 for delusions. In studies using proper intention-to-treat statistics the effect sizes were 0.10 for positive symptoms and -0.02 for delusions. The moderate to high heterogeneity in most analyses suggests that processes other than MCT alone have an impact on the results.

CONCLUSIONS

The studies so far do not support a positive effect for MCT on positive symptoms, delusions and data gathering. The methodology of most studies was poor and sensitivity analyses to control for methodological flaws reduced the effect sizes considerably. More rigorous research would be helpful in order to create enough statistical power to detect small effect sizes and to reduce heterogeneity. Limitations and strengths are discussed.

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

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

Predictors of treatment dropout in self-guided web-based interventions for depression: an 'individual patient data' meta-analysis

BACKGROUND

It is well known that web-based interventions can be effective treatments for depression. However, dropout rates in web-based interventions are typically high, especially in self-guided web-based interventions. Rigorous empirical evidence regarding factors influencing dropout in self-guided web-based interventions is lacking due to small study sample sizes. In this paper we examined predictors of dropout in an individual patient data meta-analysis to gain a better understanding of who may benefit from these interventions.

METHOD

A comprehensive literature search for all randomized controlled trials (RCTs) of psychotherapy for adults with depression from 2006 to January 2013 was conducted. Next, we approached authors to collect the primary data of the selected studies. Predictors of dropout, such as socio-demographic, clinical, and intervention characteristics were examined.

RESULTS

Data from 2705 participants across ten RCTs of self-guided web-based interventions for depression were analysed. The multivariate analysis indicated that male gender [relative risk (RR) 1.08], lower educational level (primary education, RR 1.26) and co-morbid anxiety symptoms (RR 1.18) significantly increased the risk of dropping out, while for every additional 4 years of age, the risk of dropping out significantly decreased (RR 0.94).

CONCLUSIONS

Dropout can be predicted by several variables and is not randomly distributed. This knowledge may inform tailoring of online self-help interventions to prevent dropout in identified groups at risk.

Long-term efficacy of indicated prevention of depression in non-professional caregivers: randomized controlled trial

BACKGROUND

Although depression is a common problem among non-professional caregivers, only one trial has evaluated the efficacy of indicated prevention targeting this population and the long-term efficacy is unknown. The aim of this study was to evaluate the long-term efficacy of a brief intervention for the indicated prevention of depression in a sample of female caregivers.

METHOD

A randomized controlled trial was conducted involving 173 participants (mean age 53.9 years) who were allocated to the intervention (n = 89) or the usual-care control group (n = 84). Blinded interviewers conducted assessments at 1, 3, 6 and 12 months of follow-up. The main outcome measure was the incidence of major depression and the secondary outcomes were compliance with treatment, depressive symptoms, emotional distress and caregiver burden.

RESULTS

At the 12-month follow-up, a lower incidence of depression as evaluated using the Structured Clinical Interview for Axis I Disorders of the DSM-IV was found in the intervention group compared with the control group (10.1% v. 25.0%). The relative risk was 0.40 and statistically significant [χ2 = 6.68, degrees of freedom = 1, p = 0.010, 95% confidence interval (CI) 0.20-0.81], and the number needed to treat was 7 (95% CI 4-27). There was a significant delay in the onset of depression in the intervention group (p = 0.008). The good complier caregivers had a lower incidence of depression. The intervention effect on depressive symptoms, emotional distress and caregiver burden were maintained for 12 months.

CONCLUSIONS

This is the first study to demonstrate that a brief problem-solving intervention can prevent the onset of depression among non-professional caregivers over the longer term.

Cost-effectiveness of preventing first-episode psychosis in ultra-high-risk subjects: multi-centre randomized controlled trial

BACKGROUND

Although there is evidence for the effectiveness of interventions for psychosis among ultra-high-risk (UHR) groups, health economic evaluations are lacking. This study aimed to determine the cost effectiveness and cost-utility of cognitive-behavioural therapy (CBT) to prevent first-episode psychosis.

METHOD

The Dutch Early Detection and Intervention Evaluation study was a randomized controlled trial of 196 UHR patients with an 18-month follow-up. All participants were treated with routine care (RC) for non-psychotic disorders. The experimental group (n = 95) received add-on CBT to prevent first-episode psychosis. We report the intervention, medical and travel costs, as well as costs arising from loss of productivity. Treatment response was defined as psychosis-free survival and quality-adjusted life years (QALYs) gained.

RESULTS

In the cost-effectiveness analysis, the proportion of averted psychoses was significantly higher in the CBT condition (89.5% v. 76.2%). CBT showed a 63.7% probability of being more cost effective, because it was less costly than RC by US$844 (£551) per prevented psychosis. In the cost-utility analysis, QALY health gains were slightly higher for CBT than for RC (0.60 v. 0.57) and the CBT intervention had a 52.3% probability of being the superior treatment because, for equal or better QALY gains, the costs of CBT were lower than those of RC.

CONCLUSIONS

Add-on preventive CBT for UHR resulted in a significant reduction in the incidence of first psychosis. QALY gains show little difference between the two conditions. The CBT intervention proved to be cost saving.

Adapted cognitive-behavioural therapy required for targeting negative symptoms in schizophrenia: meta-analysis and meta-regression

BACKGROUND

There is an increasing interest in cognitive-behavioural therapy (CBT) interventions targeting negative symptoms in schizophrenia. To date, CBT trials primarily focused on positive symptoms and investigated change in negative symptoms only as a secondary outcome. To enhance insight into factors contributing to improvement of negative symptoms, and to identify subgroups of patients that may benefit most from CBT directed at ameliorating negative symptoms, we reviewed all available evidence on these outcomes.

METHOD

A systematic search of the literature was conducted in PsychInfo, PubMed and the Cochrane register to identify randomized controlled trials reporting on the impact of CBT interventions on negative symptoms in schizophrenia. Random-effects meta-analyses were performed on end-of-treatment, short-term and long-term changes in negative symptoms.

RESULTS

A total of 35 publications covering 30 trials in 2312 patients, published between 1993 and 2013, were included. Our results showed studies' pooled effect on symptom alleviation to be small [Hedges' g = 0.093, 95% confidence interval (CI) -0.028 to 0.214, p = 0.130] and heterogeneous (Q = 73.067, degrees of freedom = 29, p < 0.001, τ 2 = 0.081, I 2 = 60.31) in studies with negative symptoms as a secondary outcome. Similar results were found for studies focused on negative symptom reduction (Hedges' g = 0.157, 95% CI -0.10 to 0.409, p = 0.225). Meta-regression revealed that stronger treatment effects were associated with earlier year of publication, lower study quality and with CBT provided individually (as compared with group-based).

CONCLUSIONS

The co-occurring beneficial effect of conventional CBT on negative symptoms found in older studies was not supported by more recent studies. It is now necessary to further disentangle effective treatment ingredients of older studies in order to guide the development of future CBT interventions aimed at negative symptom reduction.

A novel mouse model for Sézary syndrome using xenotransplantation of Sézary cells into immunodeficient RAG2(-/-) γc(-/-) mice

Sézary syndrome (SS) is an aggressive cutaneous T-cell lymphoma with CD4+ tumor cells localized in the skin, lymph nodes and peripheral blood. Characteristic molecular aberrancies in SS have been identified; however, paucity of functional models severely hampered the translation of these observations into pathogenic mechanisms, and subsequent validation of novel therapeutic targets. We therefore developed a mouse model for SS using intrahepatic injection of SS cells in newborn immunodeficient RAG2(-/-) γc(-/-) mice that are completely devoid of T-, B- and NK-cell activity. Injection of the SS cell line SeAx led to long-term and reproducible systemic repopulation of the mice. Injection of mice with the SS cell line HuT-78 led to the death of the mice owing to massive growth of internal tumors. Four weeks after injection of primary SS cells, human CD3+ T cells could be tracked back in the liver, peripheral blood, lymph nodes, spleen and skin of the mice, although the engraftment rate varied when using cells from different patients. In conclusion, we demonstrate that injection of SS cell lines or primary cells in newborn RAG2(-/-) γc(-/-) mice results in long-term systemic repopulation of the mice, thereby providing a novel mouse model for Sézary syndrome.

Life review therapy for older adults with moderate depressive symptomatology: a pragmatic randomized controlled trial

BACKGROUND. Although there is substantial evidence for the efficacy of life review therapy as an early treatment of depression in later life, its effectiveness in natural settings has not been studied. The present study evaluates an intervention based on life review and narrative therapy in a large multi-site, pragmatic randomized controlled trial(RCT). METHOD. Life review therapy was compared with care as usual. The primary outcome was depressive symptoms;secondary outcomes were anxiety symptoms, positive mental health, quality of life, and current major depressive episode (MDE). To identify groups for whom the intervention was particularly effective, moderator analyses were carried out (on sociodemographic variables, personality traits, reminiscence functions, clinically relevant depressive and anxiety symptoms, and past MDEs). RESULTS. Compared with care as usual (n=102), life review therapy (n=100) was effective in reducing depressive symptoms, at post-treatment (d=0.60, B= -5.3, p<0.001), at 3-month follow-up (d=0.50, B= -5.0, p<0.001) and for the intervention also at 9-month follow-up (t=5.7, p<0.001). The likelihood of a clinically significant change in depressive symptoms was significantly higher [odds ratio (OR) 3.77, p<0.001 at post-treatment ; OR 3.76, p<0.001 at the 3-month follow-up]. Small significant effects were found for symptoms of anxiety and positive mental health.Moderator analyses showed only two significant moderators, the personality trait of extraversion and the reminiscence function of boredom reduction. CONCLUSIONS. This study shows the effectiveness of life review therapy as an early intervention for depression in an ecologically valid context, supporting its applicability to a broad target group. The intervention is also effective in reducing anxiety symptoms and strengthening positive mental health.

Proximal fluid proteome profiling of mouse colon tumors reveals biomarkers for early diagnosis of human colorectal cancer

PURPOSE

Early detection of colorectal cancer (CRC) and its precursor lesions is an effective approach to reduce CRC mortality rates. This study aimed to identify novel protein biomarkers for the early diagnosis of CRC.

EXPERIMENTAL DESIGN

Proximal fluids are a rich source of candidate biomarkers as they contain high concentrations of tissue-derived proteins. The FabplCre;Apc(15lox/+) mouse model represents early-stage development of human sporadic CRC. Proximal fluids were collected from normal colon and colon tumors and subjected to in-depth proteome profiling by tandem mass spectrometry. Carcinoembryonic antigen (CEA) and CHI3L1 human serum protein levels were determined by ELISA.

RESULTS

Of the 2,172 proteins identified, quantitative comparison revealed 192 proteins that were significantly (P < 0.05) and abundantly (>5-fold) more excreted by tumors than by controls. Further selection for biomarkers with highest specificity and sensitivity yielded 52 candidates, including S100A9, MCM4, and four other proteins that have been proposed as candidate biomarkers for human CRC screening or surveillance, supporting the validity of our approach. For CHI3L1, we verified that protein levels were significantly increased in sera from patients with adenomas and advanced adenomas compared with control individuals, in contrast to the CRC biomarker CEA.

CONCLUSION

These data show that proximal fluid proteome profiling with a mouse tumor model is a powerful approach to identify candidate biomarkers for early diagnosis of human cancer, exemplified by increased CHI3L1 protein levels in sera from patients with CRC precursor lesions.

Fifty years of thoracic surgical research in South Africa

AIM

To investigate the scope and trends in clinical research in South African thoracic surgery between 1955 and 2006 and to measure its impact on clinical practice.

METHOD

A systematic review of all SA thoracic surgical publications was performed.

RESULTS

There were 252 general thoracic publications and a marked decrease in publications was noted after the peak period of productivity of the 1980s. There was a shift toward the private sector as an origin of articles and toward a local, non-indexed journal. Inflammatory lung disease was the most frequent topic of publication. Case series and case reports were the most frequent type of article.

CONCLUSION

The vulnerability of a small specialty in a developing country is illustrated by the clear trends that emerged. The study provides important indicators for future research, highlights the need for a national database of clinical experience, and emphasises the importance of rekindling interest and a culture of research in thoracic surgery.

Incidence of social phobia and identification of its risk indicators: a model for prevention

OBJECTIVE

This study seeks to examine the incidence of social phobia in the general population and to establish a number of risk indicators.

METHOD

Data were derived from the Netherlands Mental Health Survey and Incidence Study (NEMESIS) which is a population based prospective study (n=7076). A sample of adults aged 18-64 years (n=5618) were re-interviewed 1 year later using Composite International Diagnostic Interview (CIDI).

RESULTS

The 12-month incidence of DSM-III-R social phobia was 1.0%. Low education, low mastery, low self-esteem, emotional neglect in childhood and ongoing difficulties were found to be risk indicators. After including other mental disorders as risk indicators in the model, the incidence was found to be more common among those with low mastery, major depression, subthreshold social phobia, emotional neglect, negative life events, and low education.

CONCLUSION

The incidence of social phobia can be predicted relatively well with psychosocial variables and comorbidity.

On-line and Off-line Strategies for Preventing Depression

Depression is associated with a formidable disease burden and has substantial economic ramifications. Its burden can only be partially alleviated through treatment. To make a more substantial impact on population health, we need primary prevention to reduce the number of new cases, and we need to do a better job about preventing relapses and recurrences. In this symposium we will present the latest evidence that prevention is a viable option: it is effective and cost-effective when offered as CBT-based self-help (bibliotherapy), and as preventive cognitive therapy for relapses and recurrences. The last couple of years witnessed a new approach to improving population health when some of these preventive interventions became available as internet-based interventions. These on-line interventions can be well structured and conducted either as pure self-help or with support by a therapist. We assume that on-line interventions are acceptable, because people can access these interventions in the privacy of their homes, at times they find convenient, and at a pace that suits them best. We also expect that these interventions can be cost-effective, especially when offered as self-help. Finally, we expect that on-line interventions have great potential to reach many people. It is therefore interesting to outline some of these new strategies and present evidence of their (cost) effectiveness.

[Subclinical depression: a clinically relevant condition?]

BACKGROUND

Subclinical depression is a condition in which a person has depressive symptoms but does not meet the criteria for a depressive disorder.

AIM

To give insight in the clinical relevance of subclinical depression. method A review of a series of studies that the authors co-authored on the subject of subclinical depression. results These studies showed that subthreshold depression has serious consequences for the quality of life, but not as serious as in the case of a depressive disorder. It was also found that subthreshold (minor) depression can have considerable economic consequences for the individual concerned, although again less severe than if the individual had a depressive disorder. Because minor depression was more prevalent, the total costs of minor depression in the Netherlands (EUR 1.5 billion per year) appeared to be comparable to those of major depression (EUR 1.8 billion). It was also clear that subjects with subthreshold depression have an increased risk of developing a major depression. The degree of risk depended on a number of factors, including the definition of subthreshold depression. meta-analysis of seven studies examining the effects of psychological treatments of subthreshold depression showed that these treatments are effective (Cohen's d = 0.42; 95% ci: 0.23-0.60) and that they may well prevent the onset of major depression (incidence rate ratio: 0.70; 95% ci: 0.47-1.03; p < 0.1).

CONCLUSION

Subthreshold depression has serious consequences for the quality of life, but not as serious as in the case of a depressive disorder. Psychological treatment is effective.

Recombinant human deoxyribonuclease for the treatment of acute asthma in children

BACKGROUND

Airway obstruction in acute asthma is the result of airway smooth muscle contraction, inflammation and mucus plugging. Case reports suggest that mucolytic therapy might be beneficial in acute asthma. The aim of this study was to determine the efficacy of the mucolytic drug recombinant human deoxyribonuclease (rhDNase) in addition to standard treatment at the emergency department in children with an asthma exacerbation.

METHODS

In a multicentre randomised double-blind controlled clinical trial, 121 children brought to the emergency room for a moderate to severe asthma exacerbation were randomly assigned to receive either a single dose of 5 mg nebulised rhDNase or placebo following the second dose of bronchodilators. An asthma score (scale 5-15) was assessed at baseline and at 1, 2, 6, 12 and 24 h. The primary outcome variable was the asthma score 1 h after the study medication.

RESULTS

One hour after the study medication the asthma score in the rhDNase group showed an adjusted mean decrease from baseline of 1.0 (95% CI 0.5 to 1.6) points compared with 0.7 (95% CI 0.3 to 1.2) points in the placebo group (mean difference 0.4 (95% CI -0.2 to 1.0) points; p = 0.23). The asthma score over the study period of 24 h also did not differ significantly between the rhDNase and placebo group (mean difference 0.2 (95% CI -0.3 to 0.7) points, p = 0.40). The duration of oxygen supplementation and number of bronchodilator treatments in the first 24 h were similar in both groups.

CONCLUSION

Adding a single dose of nebulised rhDNase to standard treatment in the emergency room has no beneficial effects in children with moderate to severe acute asthma.

Completeness of notification of tuberculosis in The Netherlands: how reliable is record-linkage and capture-recapture analysis?

The aim of this study was to describe a systematic process of record-linkage, cross-validation, case-ascertainment and capture-recapture analysis to assess the quality of tuberculosis registers and to estimate the completeness of notification of incident tuberculosis cases in The Netherlands in 1998. After record-linkage and cross-validation 1499 tuberculosis patients were identified, of whom 1298 were notified, resulting in an observed under-notification of 13.4%. After adjustment for possible imperfect record-linkage and remaining false-positive hospital cases observed under-notification was 7.3%. Log-linear capture-recapture analysis initially estimated a total number of 2053 (95% CI 1871-2443) tuberculosis cases, resulting in an estimated under-notification of 36.8%. After adjustment for possible imperfect record-linkage and remaining false-positive hospital cases various capture-recapture models estimated under-notification at 13.6%. One of the reasons for the higher than expected estimated under-notification in a country with a well-organized system of tuberculosis control might be that some tuberculosis cases, e.g. extrapulmonary tuberculosis, are managed by clinicians less familiar with notification of infectious diseases. This study demonstrates the possible impact of violation of assumptions underlying capture-recapture analysis, especially the perfect record-linkage, perfect positive predictive value and absent three-way interaction assumptions.

Estimating the coverage of a targeted mobile tuberculosis screening programme among illicit drug users and homeless persons with truncated models

Truncated models are indirect methods to estimate the size of a hidden population which, in contrast to the capture-recapture method, can be used on a single information source. We estimated the coverage of a tuberculosis screening programme among illicit drug users and homeless persons with a mobile digital X-ray unit between 1 January 2003 and 31 December 2005 in Rotterdam, The Netherlands, using truncated models. The screening programme reached about two-third of the estimated target population at least once annually. The intended coverage (at least two chest X-rays per person per year) was about 23%. We conclude that simple truncated models can be used relatively easily on available single-source routine data to estimate the size of a population of illicit drug users and homeless persons. We assumed that the most likely overall bias in this study would be overestimation and therefore the coverage of the targeted mobile tuberculosis screening programme would be higher.

Psychological treatments of subthreshold depression: a meta-analytic review

OBJECTIVE

Subthreshold depression has a considerable impact on the quality of life and carries a high risk of developing major depressive disorder. Psychological treatments for subthreshold depression may be able to reduce depressive symptomatology and prevent the onset of major depression.

METHOD

We conducted a meta-analysis of randomized controlled studies examining the effects of psychological treatments for subthreshold depression. We examined the effects on depressive symptoms and the preventive effects on the incidence of major depression.

RESULTS

Seven high-quality studies with a total of 700 subjects were included. The mean effect size at post-test was 0.42 (95% CI: 0.23-0.60), with very low heterogeneity. The relative risk of developing a major depressive disorder in subjects who received the intervention was 0.70 (95% CI: 0.47-1.03; P = 0.07).

CONCLUSION

Psychological treatments have significant effects on subthreshold depression. Furthermore, these interventions may prevent the onset of major depression.

Estimating infectious diseases incidence: validity of capture-recapture analysis and truncated models for incomplete count data

Capture-recapture analysis has been used to evaluate infectious disease surveillance. Violation of the underlying assumptions can jeopardize the validity of the capture-recapture estimates and a tool is needed for cross-validation. We re-examined 19 datasets of log-linear model capture-recapture studies on infectious disease incidence using three truncated models for incomplete count data as alternative population estimators. The truncated models yield comparable estimates to independent log-linear capture-recapture models and to parsimonious log-linear models when the number of patients is limited, or the ratio between patients registered once and twice is between 0.5 and 1.5. Compared to saturated log-linear models the truncated models produce considerably lower and often more plausible estimates. We conclude that for estimating infectious disease incidence independent and parsimonious three-source log-linear capture-recapture models are preferable but truncated models can be used as a heuristic tool to identify possible failure in log-linear models, especially when saturated log-linear models are selected.

Economic costs of minor depression: a population-based study

OBJECTIVE

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

METHOD

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

RESULTS

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

CONCLUSION

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

[The prevention of psychiatric disorders]

About 450 million people all over the world suffer from psychiatric disorders. Limitations and handicaps are caused especially by unipolar depression, excessive alcohol consumption, schizophrenia and manic-depressive disorder. It is expected that the importance of psychiatric disorders for public health will increase in the coming decades. Psychiatric disorders are often the cause of death, destroy the lives of both patients and their families, have far-reaching economic consequences and are often complicated by somatic diseases. The advances in the field of treatment are impressive but can have only a limited effect on the consequences of psychiatric disorders for public health. The incidence of psychiatric disorders can be reduced by more than 25%. The greatest effects have been seen with depressive disorders, indicated prevention and the use of cognitive therapy. Indicated prevention has also been found to be effective in psychotic disorders. Debriefing is ineffective in posttraumatic stress disorder. The efficacy of universal prevention has not been investigated. There are still insufficient data to develop evidence-based guidelines for the prevention of psychiatric disorders.

Creative reminiscence as an early intervention for depression: results of a pilot project

Reminiscence may help in resolving conflicts from the past and making up the balance of one's life. Life-review may be further enhanced by the creative expression of memories in stories, poems or drawings. In this way people are encouraged to create and discover metaphors, images and stories that symbolically represent the subjective and inner meaning of their lives. In this article, a new intervention, which combines reminiscence and creative expression aimed at early treatment of depression, is described. A pilot project showed that the intervention Searching for the meaning in life may generate small-sized effects in reducing depression. Additionally, it appears to generate effects of medium size in enhancing mastery. Several possible ways to improve the effectiveness of the intervention are described.

Predicting the onset of major depression in subjects with subthreshold depression in primary care: a prospective study

OBJECTIVE

That subjects with subthreshold depression have an increased probability of developing major depression has been confirmed by many studies. However, the factors which may predict the onset of major depression have yet to be fully examined.

METHOD

We examined the control group of a randomized trial in primary care patients with subthreshold depression (N = 109), of whom 20 had developed major depression 1 year later. Using the vulnerability-stress theory, we examined which factors predicted the onset of major depression.

RESULTS

In both univariate and multivariate analyses, family history and chronic illnesses predicted the onset of major depression.

CONCLUSION

It is possible to predict to a certain degree whether a subject with subthreshold depression will develop major depression within a year.

Subthreshold depression as a risk indicator for major depressive disorder: a systematic review of prospective studies

OBJECTIVE

In order to examine whether the incidence of major depressive disorder (MDD) is increased in subjects with subthreshold depression, or sD (clinically relevant depressive symptoms, without meeting criteria for a full-blown MDD), we conducted a review of prospective studies examining the incidence of MDD in subjects with sD.

METHOD

A systematic literature search was conducted. For all studies, the relative risk of developing MDD was calculated, based on person-years.

RESULTS

Twenty studies (23 comparisons) were found, based on community samples, general medical patients and high-risk subjects. Most comparisons showed that subjects with sD had a consistently larger chance of developing MDD. The studies differed considerably in the definition of sD, the recency (occurrence of the last sD) and the in-/exclusion of lifetime MDD.

CONCLUSION

The incidence of MDD in subjects with sD is larger than in subjects without sD. Otherwise, the concept of sD is too broad to be used. In future studies, some consensus should be reached regarding the definition of sD.

Guidance for the safety assessment of botanicals and botanical preparations for use in food and food supplements

There is a growing interest by both consumers and industry for the development of food products with 'functional' properties, or health benefits. These products may take the form of dietary supplements or of foods. The health benefits are given by particular ingredients, and in many cases these are derived from botanicals. The variety of plants providing these functions is large, ranging from staple food sources such as cereals, fruits and vegetables, to herbals as used in traditional medicine. The food or ingredient conferring health properties may consist of the plants themselves, extracts thereof, or more purified components. The scientific literature is abundant with articles not only on the beneficial properties, but also on possible adverse health effects of plants and their components. The present report discusses the data required to determine the safe use of these types of ingredients, and provides advice on the development of risk assessment strategies consistent with due diligence under existing food regulations. Product specifications, composition and characterisation of standardised and authentic materials, documented history of use and comparison to existing products (taking into account the effect of industrial processing), description of the intended use and consequent exposure are highlighted as key background information on which to base a risk evaluation. The extent of experimental investigation required, such as in vitro, animal, and/or human studies, depends on the adequacy of this information. A decision tree is presented as an aid to determine the extent of data requirements based on product comparison. The ultimate safety in use depends on the establishment of an adequate safety margin between expected exposure and identified potential hazards. Health hazards may arise from inherent toxicities or contaminants of the plant materials, including the mechanism of the intended beneficial effect. A lower safety margin may therefore be expected than for food ingredients or additives where no physiological effects are intended. In rare cases, post launch monitoring programmes may be envisaged to confirm expected exposures and adequacy of the safety margin. This guidance document was elaborated by an expert group of the Natural Toxin Task Force of the European Branch of the International Life Sciences Institute--ILSI Europe and discussed with a wider audience of scientists at a workshop held on 13-15 May 2002 in Marseille, France.

[Cannabis use as a probable causative factor in the later development of schizophrenia]

OBJECTIVE

To study the role of cannabis use in the onset of symptoms and disorders in the schizophrenia spectrum.

DESIGN

Literature study.

METHOD

Hypothetical explanations of the relationship between cannabis use and subsequent schizophrenia were assessed on the basis of the results of five large longitudinal studies.

RESULTS

Because cannabis use preceded the development of schizophrenia and as a result of statistical control for possible confounders, the following explanations could be rejected: 'cannabis is used as self-medication for schizophrenia', 'schizophrenia is not caused by cannabis but by other drugs that are used concurrently', and 'cannabis use and schizophrenia are both caused by other factors'. Two explanations then remained: 'cannabis use per se contributes in a unique manner to the risk' and 'cannabis use, in interaction with other risk factors, leads to an increase in the risk'.

CONCLUSION

There are strong indications that cannabis use increases the risk of the subsequent development of symptoms and disorders in the schizophrenia spectrum.

Predictors of first incidence of DSM-III-R psychiatric disorders in the general population: findings from the Netherlands Mental Health Survey and Incidence Study

OBJECTIVE

To investigate determinants of 12-month first incidence of DSM-III-R mood disorder (MD), anxiety disorder (AD) and substance use disorder (SUD) in the general population.

METHOD

Data are from the Netherlands Mental Health Survey and Incidence Study (NEMESIS), a prospective epidemiologic study in which a representative sample of 7076 adults aged 18-64 years were interviewed with the Composite International Diagnostic Interview. New cases diagnosed 12 months after baseline were compared with never diagnosed controls on sociodemographic and psychosocial variables.

RESULTS

Multivariate, the only demographic variable associated with incidence of MD was female gender. The strongest predictors were negative life events and ongoing difficulties. High level of neuroticism was also associated. Incidence of AD was likewise predicted by female gender. Negative life events and ongoing difficulties were also significant predictors, though weaker than for MD. Incidence of SUD was more common among males, young adults, people not living with a partner and those experiencing positive life events.

CONCLUSION

Incident MD and AD were predicted more strongly by life events, and SUD more strongly by demographic factors.

Underreporting of malaria incidence in The Netherlands: results from a capture-recapture study

The aim of this study was to estimate the completeness of notification of malaria by physicians and laboratories in the Netherlands in 1996. We used a capture-recapture (CRC) analysis of three incomplete, partially overlapping registers of malaria cases: a laboratory survey, the Notification Office and the hospital admission registration. The response of the laboratories was 83.2%. In 1996 the laboratories microscopically identified 535 cases of malaria, 330 patients with malaria were admitted to hospital and physicians notified 311 malaria cases. 667 malaria cases were recorded in at least one register. CRC analysis estimated the total number of malaria cases at 774 (95 % CI of 740-821). This implies a completeness of notification of 40.2% for physicians and 69.1% for the laboratories. It can be concluded that laboratory-based notification can considerably increase the number of officially reported malaria cases as compared to notification by physicians. However, possibly one-third of the cases may still go unreported.

Assessing parental alcoholism: a comparison of the family history research diagnostic criteria versus a single-question method

This study compares two methods of determining parental alcoholism: (1) a single question asking whether one of the subject's parents had alcohol problems; (2) the Family History Research Diagnostic Criteria (FH-RDC), which require at least one alcohol-related problem in addition to parental problem drinking. We sought first to determine the level of agreement between the single-question approach and the full FH-RDC for parental alcoholism, and then to gauge how much bias will be introduced by using the single question rather than the FH-RDC-method in assessing the risk for psychiatric disorders. Data were taken from the National Comorbidity Survey (NCS), a nationwide survey of the noninstitutionalized US civilian population aged 15 to 54. Parental alcoholism was assessed both by the single question and by the full FH-RDC. Psychiatric disorders were assessed with the Composite International Diagnostic Interview (CIDI). Good agreement was found between the single-question approach and the FH-RDC (kappa = 0.83). The single-question method introduces only a small downward bias when it comes to assessing the risk for psychiatric disorders in children of alcoholic probands. This underestimation does not reach statistical significance. When a questionnaire needs to be shortened, a single question on parental problem drinking is a good alternative to checking all individual FH-RDC items.

[HIV-positive drug users in South Limburg: number and characteristics, a capture-recapture analysis]

OBJECTIVE

To estimate the number of HIV positive drug abusers (HDs) in South Limburg, the Netherlands, and to ascertain the characteristics of this group, so that special HIV healthcare can be planned.

DESIGN

Capture-recapture analysis.

METHOD

Capture-recapture analysis was carried out and abuser characteristics were determined using three incomplete, partially overlapping registers of HDs from the regional AIDS hospital, the Regional Institute for Addiction and the Municipal Health Service Centres in South Limburg.

RESULTS

From the 80 HDs included, the Municipal Health Service Centres observed 59 HDs, the Institute for Addiction 45 and the hospital 44. The capture-recapture analysis gave an estimate of 110 HDs (95% CI: 91-164) in South Limburg. Assuming 1100 drug users in South Limburg of which 76% had injected on one or more occasions, the HIV prevalence among injecting drug users was estimated at 13% (110/836). From the observed HDs 80% were male, with a mean age of 38 years (SD: 7) and a mean age at the onset of drug use of 18 years (SD: 5). All HDs currently injected or had previously injected. The first injected drugs were used at a mean age of 21 years (SD: 6). All HDs used heroine, 84% also used cocaine, 54% were homeless, 91% unemployed and 80% had a history of imprisonment. Further, 71% of the female HDs were prostitutes, 37% of the male ones visited prostitutes, 81% had contracted hepatitis B (of which 20% were a carrier) and all HDs were infected with hepatitis C. An estimate based on prevalence data gave 143/836 (17%) and that based on capture-recapture analysis with two registrations was 102/836 (12%).

CONCLUSION

The number of HDs was estimated to be 110. The population had a marginalized existence and there was a risk of HIV spreading.

The structure and stability of common mental disorders: the NEMESIS study

BACKGROUND

We analyzed the underlying latent structure of 12-month DSM-III-R diagnoses of 9 common disorders for the general population in the Netherlands. In addition, we sought to establish (1) the stability of the latent structure underlying mental disorders across a 1-year period (structural stability) and (2) the stability of individual differences in mental disorders at the level of the latent dimensions (differential stability).

METHODS

Data were obtained from the first and second measurement of the Netherlands Mental Health Survey and Incidence Study (NEMESIS) (response rate at baseline: 69.7%, n = 7076; 1 year later, 79.4%, n = 5618). Nine common DSM-III-R diagnoses were assessed twice with the Composite International Diagnostic Interview with a time lapse of 1 year. Using structural equation modeling, the number of latent dimensions underlying these diagnoses was determined, and the structural and differential stability were assessed.

RESULTS

A 3-dimensional model was established as having the best fit: a first dimension underlying substance use disorders (alcohol dependence, drug dependence); a second dimension for mood disorders (major depression, dysthymia), including generalized anxiety disorder; and a third dimension underlying anxiety disorders (simple phobia, social phobia, agoraphobia, and panic disorder). The structural stability of this model during a 1-year period was substantial, and the differential stability of the 3 latent dimensions was considerable.

CONCLUSIONS

Our results confirm the 3-dimensional model for 12-month prevalence of mental disorders. Results underline the argument for focusing on core psychopathological processes rather than on their manifestation as distinguished disorders in future population studies on common mental disorders.