Ina Marteinsdottir

A systematic review including meta-analysis of work environment and depressive symptoms.

BackgroundDepressive symptoms are potential outcomes of poorly functioning work environments. Such symptoms are frequent and cause considerable suffering for the employees as well as financial loss for the employers. Accordingly good prospective studies of psychosocial working conditions and depressive symptoms are valuable. Scientific reviews of such studies have pointed at methodological difficulties but still established a few job risk factors. Those reviews were published some years ago. There is need for an updated systematic review using the GRADE system. In addition, gender related questions have been insufficiently reviewed.MethodInclusion criteria for the studies published 1990 to June 2013: 1. European and English speaking countries. 2. Quantified results describing the relationship between exposure (psychosocial or physical/chemical) and outcome (standardized questionnaire assessment of depressive symptoms or interview-based clinical depression). 3. Prospective or comparable case-control design with at least 100 participants. 4. Assessments of exposure (working conditions) and outcome at baseline and outcome (depressive symptoms) once again after follow-up 1-5 years later. 5. Adjustment for age and adjustment or stratification for gender.Studies filling inclusion criteria were subjected to assessment of 1.) relevance and 2.) quality using predefined criteria. Systematic review of the evidence was made using the GRADE system. When applicable, meta-analysis of the magnitude of associations was made. Consistency of findings was examined for a number of possible confounders and publication bias was discussed.ResultsFifty-nine articles of high or medium high scientific quality were included. Moderately strong evidence (grade three out of four) was found for job strain (high psychological demands and low decision latitude), low decision latitude and bullying having significant impact on development of depressive symptoms. Limited evidence (grade two) was shown for psychological demands, effort reward imbalance, low support, unfavorable social climate, lack of work justice, conflicts, limited skill discretion, job insecurity and long working hours. There was no differential gender effect of adverse job conditions on depressive symptomsConclusionThere is substantial empirical evidence that employees, both men and women, who report lack of decision latitude, job strain and bullying, will experience increasing depressive symptoms over time. These conditions are amenable to organizational interventions.

A systematic review including meta-analysis of work environment and burnout symptoms

BackgroundPractitioners and decision makers in the medical and insurance systems need knowledge on the relationship between work exposures and burnout. Many burnout studies – original as well as reviews - restricted their analyses to emotional exhaustion or did not report results on cynicism, personal accomplishment or global burnout. To meet this need we carried out this review and meta-analyses with the aim to provide systematically graded evidence for associations between working conditions and near-future development of burnout symptoms.MethodsA wide range of work exposure factors was screened. Inclusion criteria were: 1) Study performed in Europe, North America, Australia and New Zealand 1990–2013. 2) Prospective or comparable case control design. 3) Assessments of exposure (work) and outcome at baseline and at least once again during follow up 1–5 years later. Twenty-five articles met the predefined relevance and quality criteria. The GRADE-system with its 4-grade evidence scale was used.ResultsMost of the 25 studies focused emotional exhaustion, fewer cynicism and still fewer personal accomplishment. Moderately strong evidence (grade 3) was concluded for the association between job control and reduced emotional exhaustion and between low workplace support and increased emotional exhaustion. Limited evidence (grade 2) was found for the associations between workplace justice, demands, high work load, low reward, low supervisor support, low co-worker support, job insecurity and change in emotional exhaustion. Cynicism was associated with most of these work factors. Reduced personal accomplishment was only associated with low reward. There were few prospective studies with sufficient quality on adverse chemical, biological and physical factors and burnout.ConclusionWhile high levels of job support and workplace justice were protective for emotional exhaustion, high demands, low job control, high work load, low reward and job insecurity increased the risk for developing exhaustion. Our approach with a wide range of work exposure factors analysed in relation to the separate dimensions of burnout expanded the knowledge of associations, evidence as well as research needs. The potential of organizational interventions is illustrated by the findings that burnout symptoms are strongly influenced by structural factors such as job demands, support and the possibility to exert control.

Comorbidity of Adult ADHD and Its Subtypes With Substance Use Disorder in a Large Population-Based Epidemiological Study

Objective: The objective of the study is to explore the role and possible substance preference in ADHD and subtypes in substance use disorder (SUD). Method: Using self-report data on ADHD Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) symptoms and SUD (alcohol, illicit drugs, and nicotine) in 18,167 Swedish twins, aged 20 to 45 years, we obtained odds ratios (OR) from mixed effect logistic regression, controlling for age, sex, education, and nonindependence of twin data. Results: Increased ADHD symptoms were significantly associated with increased odds for all SUD. ORs ranged between 1.33 for regular nicotine (95% confidence interval [CI] = [1.12, 1.59]); 2.54 for multiple drug use (95% CI = [2.00, 3.23]), and 3.58 for alcohol dependence (95% CI = [2.86, 4.49]). Conclusion: ADHD symptoms and subtypes in the population are associated with increased risks for all SUD outcomes, with no difference between ADHD subtypes, no substance preference, and no sex differences for the comorbidity. Clinicians need to consider ADHD evaluation and treatment as part of management of SUD in adults.

Serotonin synthesis rate and the tryptophan hydroxylase-2 : G-703T polymorphism in social anxiety disorder

It is disputed whether anxiety disorders, like social anxiety disorder, are characterized by serotonin over- or underactivity. Here, we evaluated whether our recent finding of elevated neural serotonin synthesis rate in patients with social anxiety disorder could be reproduced in a separate cohort, and whether allelic variation in the tryptophan hydroxylase-2 (TPH2) G-703T polymorphism relates to differences in serotonin synthesis assessed with positron emission tomography. Eighteen social anxiety disorder patients and six healthy controls were scanned during 60 minutes in a resting state using positron emission tomography and 5-hydroxy-L-[β -11C]tryptophan, [11C]5-HTP, a substrate of the second enzymatic step in serotonin synthesis. Parametric images were generated, using the reference Patlak method, and analysed using Statistical Parametric Mapping (SPM8). Blood samples for genotyping of the TPH2 G-703T polymorphism were obtained from 16 social anxiety disorder patients (T carriers: n=5, GG carriers: n=11). A significantly elevated [11C]5-HTP accumulation rate, indicative of enhanced decarboxylase activity and thereby serotonin synthesis capacity, was detected in social anxiety disorder patients compared with controls in the hippocampus and basal ganglia nuclei and, at a more lenient (uncorrected) statistical threshold, in the amygdala and anterior cingulate cortex. In patients, the serotonin synthesis rate in the amygdala and anterior cingulate cortex was significantly elevated in TPH2 T carriers in comparison with GG homozygotes. Our results support that social anxiety disorder entails an overactive presynaptic serotonergic system that, in turn, seems functionally influenced by the TPH2 G-703T polymorphism in emotionally relevant brain regions.

Genetic and environmental contributions to the association between attention deficit hyperactivity disorder and alcohol dependence in adulthood : A large population-based twin study.

Previous research indicates that attention deficit hyperactivity disorder (ADHD) frequently co‐occurs with alcohol dependence; however, the extent to which shared genetic risk factors underpin this association remains unclear. The aim of this study is to investigate the relative importance of genetic, shared, and nonshared environmental factors for the overlap between ADHD and alcohol dependence in adults. Almost 18,000 adult twins aged 20–45 years, from more than 12,000 twin pairs (5,420 complete pairs), from the population‐representative Swedish Twin Registry, were included. Self‐ratings were used to assess symptoms of ADHD and alcohol dependence. Twin analysis was used to determine the role of additive genetic (A), shared (C), and nonshared environmental (E) factors. As a result, we found a significant association between ADHD and alcohol dependence (odds ratio 3.58; 95% confidence interval, 2.85–4.49). Twin analysis suggested that shared genetic risk factors explained 64% of the overlap between ADHD and alcohol dependence. Nonshared environmental factors accounted for the remaining 36%, whereas the contribution of shared environmental factors was minimal. We found no support for statistically significant sex differences in the overlap between ADHD and alcohol dependence. In conclusion the overlap between ADHD and alcohol dependence in adulthood was largely explained by shared genetic risk factors. This is an important step toward understanding the underlying nature of the risk of alcohol dependence in patients with ADHD and suggests that individuals with ADHD and their family members are important targets for alcohol prevention and treatment.

Childhood maltreatment and attention deficit hyperactivity disorder symptoms in adults : a large twin study

BACKGROUND Childhood maltreatment (CM) has been associated with increased risk of attention deficit hyperactivity disorder (ADHD) in children and adults. It is, however, unclear whether this association is causal or due to familial confounding. METHOD Data from 18 168 adult twins, aged 20-46 years, were drawn from the population-based Swedish twin registry. Retrospective self-ratings of CM (emotional and physical neglect, physical and sexual abuse and witnessing family violence), and self-ratings for DSM-IV ADHD symptoms in adulthood were analysed. Possible familial confounding was investigated using a within twin-pair design based on monozygotic (MZ) and dizygotic (DZ) twins. RESULTS CM was significantly associated with increased levels of ADHD symptom scores in adults [regression coefficient: 0.40 standard deviations, 95% confidence interval (CI) 0.37-0.43]. Within twin-pair analyses showed attenuated but significant estimates within DZ (0.29, 95% CI 0.21-0.36) and MZ (0.18, 95% CI 0.10-0.25) twin pairs. Similar results emerged for hyperactive/impulsive and inattentive ADHD symptom scores separately in association with CM. We conducted sensitivity analyses for early maltreatment, before age 7, and for abuse and neglect separately, and found similarly reduced estimates in DZ and MZ pairs. Re-traumatization after age 7 did not significantly influence results. CONCLUSIONS CM was significantly associated with increased ADHD symptoms in adults. Associations were partly due to familial confounding, but also consistent with a causal interpretation. Our findings support cognitive neuroscience studies investigating neural pathways through which exposure to CM may influence ADHD. Clinicians treating adults with ADHD should be aware of the association with maltreatment.

Psychological Resources Are Independently Associated with Markers of Inflammation in a Middle-Aged Community Sample

PurposeTo elucidate possible independent associations of psychological resources with inflammatory markers, all linked with coronary heart disease (CHD).MethodIn a middle-aged general population (n = 944), psychological resources (coping, self-esteem, and sense of coherence (SOC)), a global measure of quality of life (Cantril’s self-anchoring ladder, also called “ladder of life”), and psychological risk factors (hopelessness, vital exhaustion, and depressive symptoms) were used in linear regression models to evaluate associations with the inflammatory markers interleukin (IL)-6, C-reactive protein (CRP), and matrix metalloproteinase (MMP)-9. Adjustments were done for age, sex, medical conditions, and cardiovascular risk factors.ResultsAfter full adjustments, self-esteem was independently associated with all three biomarkers. Ladder of life was associated with IL-6 and log-CRP; coping, vital exhaustion, and depressive symptoms with IL-6; and SOC with MMP-9 (p < 0.05 for all associations).ConclusionNumerous significant associations of psychological resources and risk factors with IL-6, CRP, and MMP-9 were found in a community-based sample. The associations of psychological resources were mostly independent, while the psychological risk factors seemed preferentially dependent on lifestyle factors as smoking, physical activity, and body mass index (BMI). This suggests that the psychological resources’ (in particular self-esteem) protective effects on CHD are linked to inflammatory markers.

Presynaptic serotonin imaging in social phobia using [3-11C]-5-hydroxy-L-tryptophan and PET

Presynaptic serotonin imaging in social phobia using [3-11C]-5-hydroxy-L-tryptophan and PET : Meeting Abstract

Genetic and environmental aspects in the association between attention-deficit hyperactivity disorder symptoms and binge-eating behavior in adults: a twin study

BACKGROUND Prior research demonstrated that attention-deficit hyperactivity disorder (ADHD) is associated with binge-eating behavior, binge-eating disorder (BED), and bulimia nervosa (BN). The aim of this study was to investigate these associations in an adult twin population, and to determine the extent to which ADHD symptoms and binge-eating behavior share genetic and environmental factors. METHODS We used self-reports of current ADHD symptoms and lifetime binge-eating behavior and associated characteristics from a sample of over 18 000 adult twins aged 20-46 years, from the population-based Swedish Twin Registry. Mixed-effects logistic regression was used to examine the association between ADHD and lifetime binge-eating behavior, BED, and BN. Structural equation modeling was used in 13 773 female twins to determine the relative contribution of genetic and environmental factors to the association between ADHD symptoms and binge-eating behavior in female adult twins. RESULTS ADHD symptoms were significantly associated with lifetime binge-eating behavior, BED, and BN. The heritability estimate for current ADHD symptoms was 0.42 [95% confidence interval (CI) 0.41-0.44], and for lifetime binge-eating behavior 0.65 (95% CI 0.54-0.74). The genetic correlation was estimated as 0.35 (95% CI 0.25-0.46) and the covariance between ADHD and binge-eating behavior was primarily explained by genetic factors (91%). Non-shared environmental factors explained the remaining part of the covariance. CONCLUSIONS The association between adult ADHD symptoms and binge-eating behavior in females is largely explained by shared genetic risk factors.

Women with Premenstrual Dysphoria Lack the Seemingly Normal Premenstrual Right-Sided Relative Dominance of 5-HTP-Derived Serotonergic Activity in the Dorsolateral Prefrontal Cortices - A Possible Cause of Disabling Mood Symptoms

Study Objective To investigate potential quantitative and qualitative differences in brain serotonergic activity between women with Premenstrual Dysphoria (PMD) and asymptomatic controls. Background Serotonin-augmenting drugs alleviate premenstrual mood symptoms in the majority of women with PMD while serotonin-depleting diets worsen PMD symptoms, both indicating intrinsic differences in brain serotonergic activity in women with PMD compared to asymptomatic women. Methods Positron-emission tomography with the immediate precursor of serotonin, 5-hydroxytryptophan (5-HTP), radiolabelled by 11C in the beta-3 position, was performed in the follicular and luteal phases for 12 women with PMD and 8 control women. Brain radioactivity–a proxy for serotonin precursor uptake and synthesis–was measured in 9 regions of interest (ROIs): the right and left sides of the medial prefrontal cortex, dorsolateral prefrontal cortex, putamen and caudate nucleus, and the single “whole brain”. Results There were no significant quantitative differences in brain 5-HTP-derived activity between the groups in either of the menstrual phases for any of the 9 ROIs. However, multivariate analysis revealed a significant quantitative and qualitative difference between the groups. Asymptomatic control women showed a premenstrual right sided relative increase in dorsolateral prefrontal cortex 5-HTP derived activity, whereas PMD women displayed the opposite (p = 0.0001). Menstrual phase changes in this asymmetry (premenstrual—follicular) correlated with changes in self ratings of ‘irritability’ for the entire group (rs = -0.595, p = 0.006). The PMD group showed a strong inverse correlation between phase changes (premenstrual—follicular) in plasma levels of estradiol and phase changes in the laterality (dx/sin) of radiotracer activity in the dorsolateral prefrontal ROI (rs = -0.635; 0.027). The control group showed no such correlation. Conclusion Absence of increased premenstrual right-sided relative 5-HTP-derived activity of the dorsolateral prefrontal cortices was found to strongly correlate to premenstrual irritability. A causal relationship here seems plausible, and the findings give further support to an underlying frontal brain disturbance in hormonally influenced serotonergic activity in women with PMD. Because of the small number of subjects in the study, these results should be considered preliminary, requiring verification in larger studies.