Stress and anxiety during pregnancy and length of gestation: a federated study using data from five Canadian and European birth cohorts.

While its etiology is not fully elucidated, preterm birth represents a major public health concern as it is the leading cause of child mortality and morbidity. Stress is one of the most common perinatal conditions and may increase the risk of preterm birth. In this paper we aimed to investigate the association of maternal perceived stress and anxiety with length of gestation. We used harmonized data from five birth cohorts from Canada, France, and Norway. A total of 5297 pregnancies of singletons were included in the analysis of perceived stress and gestational duration, and 55,775 pregnancies for anxiety. Federated analyses were performed through the DataSHIELD platform using Cox regression models within intervals of gestational age. The models were fit for each cohort separately, and the cohort-specific results were combined using random effects study-level meta-analysis. Moderate and high levels of perceived stress during pregnancy were associated with a shorter length of gestation in the very/moderately preterm interval [moderate: hazard ratio (HR) 1.92 (95%CI 0.83, 4.48); high: 2.04 (95%CI 0.77, 5.37)], albeit not statistically significant. No association was found for the other intervals. Anxiety was associated with gestational duration in the very/moderately preterm interval [1.66 (95%CI 1.32, 2.08)], and in the early term interval [1.15 (95%CI 1.08, 1.23)]. Our findings suggest that perceived stress and anxiety are associated with an increased risk of earlier birth, but only in the earliest gestational ages. We also found an association in the early term period for anxiety, but the result was only driven by the largest cohort, which collected information the latest in pregnancy. This raised a potential issue of reverse causality as anxiety later in pregnancy could be due to concerns about early signs of a possible preterm birth.

Childhood adversity and cardiovascular disease in early adulthood: a Danish cohort study.

AIMS: To examine the effect of childhood adversity on the development of cardiovascular disease (CVD) between ages 16 and 38, specifically focusing on ischaemic heart disease and cerebrovascular disease. METHODS AND RESULTS: Register data on all children born in Denmark between 1 January 1980 and 31 December 2001, who were alive and resident in Denmark without a diagnosis of CVD or congenital heart disease until age 16 were used, totalling 1 263 013 individuals. Cox proportional hazards and Aalen additive hazards models were used to estimate adjusted hazard ratios (HRs) and adjusted hazard differences of CVD from ages 16 to 38 in five trajectory groups of adversity experienced between ages 0 and 15. In total, 4118 individuals developed CVD between their 16th birthday and 31 December 2018. Compared with those who experienced low levels of adversity, those who experienced severe somatic illness and death in the family (men: adjusted HR: 1.6, 95% confidence interval: 1.4-1.8, women: 1.4, 1.2-1.6) and those who experienced very high rates of adversity across childhood and adolescence (men: 1.6, 1.3-2.0, women: 1.6, 1.3-2.0) had a higher risk of developing CVD, corresponding to 10-18 extra cases of CVD per 100 000 person-years in these groups. CONCLUSIONS: Individuals who have been exposed to childhood adversity are at higher risk of developing CVD in young adulthood compared to individuals with low adversity exposure. These findings suggest that interventions targeting the social origins of adversity and providing support for affected families may have long-term cardio-protective effects.

Can social connections become stressful? Exploring the link between social media use and perceived stress in cross-sectional and longitudinal analyses of 25,053 adults.

BACKGROUND: Social media has become a dominant part of daily lives for many, but excessive use may lead to an experience of stress. Only relatively few studies have investigated social media's influence on mental health. AIMS: We aimed to investigate whether social media use is associated with perceived stress and changes in perceived stress over 18 months. METHODS: The study population consisted of 25,053 adults (mean age 42.8; 62% women) from the SmartSleep Study. Self-reported frequency of social media use, of 10 specific social media platforms, and of perceived stress (the Perceived Stress Scale 4 item) was obtained at baseline and 18-months follow-up (N = 1745). The associations were evaluated at baseline and follow-up using multiple linear regression models adjusted for potential confounders. RESULTS: Compared to non-use, high social media use (at least every second hour) was associated with a slightly higher perceived stress level at baseline. No association was found between the frequency of social media use and changes in perceived stress during follow-up. Only small differences in these associations were noted across social media platforms. CONCLUSIONS: Further studies are needed to comprehensively explore the relationship between excessive social media use and mental health, recognizing different characteristics across social media platforms.

Early childhood adversity and body mass index in childhood and adolescence: linking registry data on adversities with school health records of 53,401 children from Copenhagen.

OBJECTIVE: We examined whether childhood adversity experienced in early childhood (0-5 years) is related to body mass index (BMI) in childhood (6-7 years) and adolescence (12-15 years). METHODS: This study combined data from the nationwide register-based DANLIFE study on childhood adversities with data on height and weight of school children in Copenhagen. Data were available for 53,401 children born in Denmark between 1980 and 1996. Children were divided into groups of early childhood adversity by applying group-based multi-trajectory modelling using their yearly count of childhood adversity in three dimensions (i.e., material deprivation, loss or threat of loss, and family dynamics) from 0-5 years. Direct and total associations between the early childhood adversity groups and BMI z-scores in childhood and adolescence were estimated using sex-stratified structural equation models. RESULTS: Five exclusive and exhaustive groups of early childhood adversity were identified, which were characterized by low adversity (51%), moderate material deprivation (30%), high material deprivation (14%), loss or threat of loss (3%) and high adversity (2%). Boys and girls exposed to moderate or high material deprivation and loss or threat of loss had a slightly higher BMI z-score, especially in adolescence, compared with those in the low adversity group, with the strongest association found for girls in the loss or threat of loss group (b (95% CI) = 0.18 (0.10, 0.26)). Additionally, boys in the high adversity group had a slightly lower BMI z-score in childhood than boys in the low adversity group (b (95% CI) = -0.12 (-0.22, -0.02)). CONCLUSIONS: Whereas associations with BMI were found for children and adolescents exposed to material deprivation, loss or threat of loss, and high adversity, the effect sizes were generally small. Contrary to prevailing hypotheses, weight changes in childhood is probably not a major explanatory mechanism linking early childhood adversity with later-life morbidity.

Pre- and perinatal exposures associated with developing pediatric-onset immune-mediated inflammatory disease: A Danish nation-wide cohort study.

OBJECTIVES: We aimed to identify pre- and perinatal risk factors for developing pediatric-onset immune-mediated inflammatory (pIMID). METHODS: This nation-wide, cohort study included all children born in Denmark from 1994 to 2014 identified from the Danish Medical Birth registry. Individuals were followed through 2014 and cross-linked to the continuously updated national socioeconomic and healthcare registers to obtain data on pre- and perinatal exposures (maternal age, educational level, smoking, maternal IMID, parity, mode of conception and delivery, plurality, child's sex, and birth season). The primary outcome was a pIMID diagnosis (inflammatory bowel disease, autoimmune hepatitis, primary sclerosing cholangitis, juvenile idiopathic arthritis, or systemic lupus erythematosus) before 18 years of age. Risk estimates were calculated using Cox proportional hazards model and presented by hazard ratios (HR) with 95% confidence intervals (95%CI). RESULTS: We included 1,350,353 children with a follow-up time of 14,158,433 person-years. Among these, 2,728 were diagnosed with a pIMID. We found a higher risk of pIMID in children born to women with a preconception IMID diagnosis (HR: 3.5 [95%CI: 2.7-4.6]), children born by Caesarean section (HR: 1.2 [95%CI: 1.0-1.3]), and among females (1.5 [95%CI: 1.4-1.6]) than among children without these characteristics. Plural pregnancies were associated with a lower risk of pIMID than single pregnancies (HR: 0.7 [95%CI: 0.6-0.9]). CONCLUSIONS: Our results indicate a high genetic burden in pIMID but also identifies intervenable risk factors, such as Cesarean section. Physicians should, keep this in mind when caring for high-risk populations and pregnant women previously diagnosed with an IMID.

Complexity in Epidemiology and Public Health. Addressing Complex Health Problems Through a Mix of Epidemiologic Methods and Data.

Public health and the underlying disease processes are complex, often involving the interaction of biologic, social, psychologic, economic, and other processes that may be nonlinear and adaptive and have other features of complex systems. There is therefore a need to push the boundaries of public health beyond single-factor data analysis and expand the capacity of research methodology to tackle real-world complexities. This article sets out a way to operationalize complex systems thinking in public health, with a particular focus on how epidemiologic methods and data can contribute towards this end. Our proposed framework comprises three core dimensions-patterns, mechanisms, and dynamics-along which complex systems may be conceptualized. These dimensions cover seven key features of complex systems-emergence, interactions, nonlinearity, interference, feedback loops, adaptation, and evolution. We relate this framework to examples of methods and data traditionally used in epidemiology. We conclude that systematic production of knowledge on complex health issues may benefit from: formulation of research questions and programs in terms of the core dimensions we identify, as a comprehensive way to capture crucial features of complex systems; integration of traditional epidemiologic methods with systems methodology such as computational simulation modeling; interdisciplinary work; and continued investment in a wide range of data types. We believe that the proposed framework can support the systematic production of knowledge on complex health problems, with the use of epidemiology and other disciplines. This will help us understand emergent health phenomena, identify vulnerable population groups, and detect leverage points for promoting public health.

Maternal stress during pregnancy and gestational duration: A cohort study from the Danish National Birth Cohort.

BACKGROUND: Preterm birth is one of the most important contributors to neonatal mortality and morbidity. Experiencing stress during pregnancy may increase the risk of adverse birth outcomes, including preterm birth. This association has been observed in previous studies, but differences in measures used limit comparability. OBJECTIVE: The objective of the study was to investigate the association between two measures of maternal stress during pregnancy, life stress and emotional distress, and gestation duration. METHODS: Women recruited in the Danish National Birth Cohort from 1996 to 2002, who provided information on their stress level during pregnancy and expecting a singleton baby, were included in the study. We assessed the associations between the level of life stress and emotional distress in quartiles, both collected at 31 weeks of pregnancy on average, and the rate of giving birth using Cox regression within intervals of the gestational period. RESULTS: A total of 80,991 pregnancies were included. Women reporting moderate or high levels of life stress vs no stress had a higher rate of giving birth earlier within all intervals of gestational age (e.g. high level: 27-33 weeks: hazard ratio (HR) 1.38, 95% confidence interval (CI) 1.04, 1.84; 34-36 weeks: 1.10, 95% CI 0.97, 1.25; 37-38 weeks: 1.21, 95% CI 1.15, 1.28). These associations between life stress and preterm birth were mainly driven by pregnancy worries. For emotional distress, a high level of distress was associated with shorter length of gestation in the preterm (27-33 weeks: 1.38, 95% CI 1.02, 1.86; 34-36 weeks: 1.05, 95% CI 0.91, 1.19) and early term (1.11, 95% CI 1.04, 1.17) intervals. CONCLUSIONS: Emotional distress and life stress were shown to be associated with gestational age at birth, with pregnancy-related stress being the single stressor driving the association. This suggests that reverse causality may, at least in parts, explain the earlier findings of stress as a risk factor for preterm birth.

Out-of-home care placement and mortality rate in early adulthood: identifying vulnerable subgroups in a nationwide cohort study.

Out-of-home care has been linked to excess mortality across the lifespan. We examined whether this association is modified by the age at first out-of-home care placement and the number of placements. In this population-based cohort study, we used register data covering all children born in Denmark between 1 and 1980 and 31 December 1999, totalling 1,111,193 individuals followed until 31 December 2018. We divided participants according to sex, out-of-home care status, age at first placement, and the number of placements. We estimated adjusted hazard ratios and hazard differences per 10,000 person-years for all-cause mortality and mortality due to suicide, accidents, and cancer between ages 18 and 39. 53,015 (4.8%) of the participants were placed in out-of-home care before age 18. The adjusted hazard ratio for all-cause mortality was 3.4 (95% CI 3.1-3.7) for males and 4.7 (4.0-5.4) for females, corresponding to 20.6 (19.0-22.2) and 10.3 (9.1-11.5) additional deaths per 10,000 individuals annually among males and females, respectively. Associations did not vary substantially according to age at first placement or the number of placements. Both males and females with a history of out-of-home care were more likely to die from suicide, accidents, and cancer compared with their peers. We show a markedly higher all-cause and cause-specific mortality among children who have been placed in out-of-home care, but contrary to our hypothesis, age at first placement and the number of placements did not modify this relation. These results warrant further investigation into potential target points for interventions that may prevent premature mortality in this group of disadvantaged individuals.

Daytime and nighttime smartphone use: A study of associations between multidimensional smartphone behaviours and sleep among 24,856 Danish adults.

The around-the-clock smartphone use and its relation to disturbed sleep is a public health concern. The present study aimed to quantify the effects of different dimensions of smartphone behaviours (frequency of daytime use, problematic use, use before sleep and use during the sleep period) on disturbed sleep (sleep quality and sleep quantity) and to disentangle their inter-relationship in a large population-based sample of 24,856 Danish adults aged ≥16 years. Data come from the SmartSleep Experiment, which is a web-based survey carried out using a citizen science approach. Tested items were used to evaluate smartphone use and disturbed sleep was evaluated with the Karolinska Sleep Questionnaire (KSQ). Linear and multinomial logistic regression was employed to evaluate the relationship between smartphone use and disturbed sleep. While several of the smartphone measures were associated with disturbed sleep when assessed individually, smartphone use during the sleep period was the only dimension consistently associated with disturbed sleep when assessed independently of other smartphone behaviours. Weekly smartphone use during the sleep period versus no use was associated on average with a 0.96 point higher score (95% confidence interval [CI] 0.90-1.02) on the 5-point KSQ scale, and a higher risk of both short (odds ratio [OR] 1.32, 95% CI 1.08-1.62) and long (OR 1.94, 95% CI 1.63-2.32) sleep duration. Smartphone use during the sleep period is the factor strongest associated to disturbed sleep relative to other dimensions of smartphone use. Recommendations around smartphone use during the sleep period are warranted in order to protect the fundamentally important biological and mental processes of sleep.

The impact of work-place social capital in hospitals on patient-reported quality of care: a cohort study of 5205 employees and 23,872 patients in Denmark.

BACKGROUND: Decision-makers increasingly consider patient-reported outcomes as important measures of care quality. Studies on the importance of work-place social capital-a collective work-place resource-for the experience of care quality are lacking. We determined the association between the level of work-place social capital and patient-reported quality of care in 148 hospital sections in the Capital Region of Denmark. METHODS: This cross-sectional study combined section-level social capital from 5205 health care professionals and 23,872 patient responses about care quality. Work-place social capital encompassed three dimensions: trust, justice and collaboration. Patient-reported quality of care was measured as: overall satisfaction, patient involvement, and medical errors. Linear regression analysis and generalized linear models assessed the mean differences in patient reported experience outcomes and the risk of belonging to the lowest tertile of care quality. RESULTS: A higher level of work-place social capital (corresponding to the interquartile range) was associated with higher patient-reported satisfaction and inpatient and acute care patient involvement. The risk of a section belonging to the lowest tertile of patient involvement was lower in sections with higher social capital providing inpatient (RR = 0.39, 0.19-0.81 per IQR increase) and acute care (RR = 0.53, 0.31-0.89). Patient-reported errors were fewer in acute care sections with higher social capital (RR = 0.65, 0.43 to 0.99). The risk of being in the lowest tertile of patient-reported satisfaction was supported for acute care sections (RR = 0.47, 0.28-0.79). CONCLUSIONS: Although we found small absolute differences in the association between patient-reported experience measures and social capital, even a small upward shift in the distribution of social capital in the hospital sector would, at the population level, have a large positive impact on patients' care experience.

Estimates of mortality attributable to COVID-19: a statistical model for monitoring COVID-19 and seasonal influenza, Denmark, spring 2020.

BackgroundTimely monitoring of COVID-19 impact on mortality is critical for rapid risk assessment and public health action.AimBuilding upon well-established models to estimate influenza-related mortality, we propose a new statistical Attributable Mortality Model (AttMOMO), which estimates mortality attributable to one or more pathogens simultaneously (e.g. SARS-CoV-2 and seasonal influenza viruses), while adjusting for seasonality and excess temperatures.MethodsData from Nationwide Danish registers from 2014-week(W)W27 to 2020-W22 were used to exemplify utilities of the model, and to estimate COVID-19 and influenza attributable mortality from 2019-W40 to 2020-W20.ResultsSARS-CoV-2 was registered in Denmark from 2020-W09. Mortality attributable to COVID-19 in Denmark increased steeply, and peaked in 2020-W14. As preventive measures and national lockdown were implemented from 2020-W12, the attributable mortality started declining within a few weeks. Mortality attributable to COVID-19 from 2020-W09 to 2020-W20 was estimated to 16.2 (95% confidence interval (CI): 12.0 to 20.4) per 100,000 person-years. The 2019/20 influenza season was mild with few deaths attributable to influenza, 3.2 (95% CI: 1.1 to 5.4) per 100,000 person-years.ConclusionAttMOMO estimates mortality attributable to several pathogens simultaneously, providing a fuller picture of mortality by COVID-19 during the pandemic in the context of other seasonal diseases and mortality patterns. Using Danish data, we show that the model accurately estimates mortality attributable to COVID-19 and influenza, respectively. We propose using standardised indicators for pathogen circulation in the population, to make estimates comparable between countries and applicable for timely monitoring.

Work-unit organizational changes and risk of cardiovascular disease: a prospective study of public healthcare employees in Denmark.

PURPOSE: The impact of organizational change at work on cardiovascular disease (CVD) among employees is poorly understood. We examined the longitudinal associations between different types of work-unit organizational changes and risk of CVD among employees. METHODS: We used multilevel mixed-effects parametric survival models to assess the risk of incident ischemic heart disease and stroke (72 events) during 2014 according to organizational changes in 2013 among 14,788 employees working in the same work unit from January through December 2013. We excluded employees with pre-existing CVD events between 2009 and 2013. Data on organizational changes defined as mergers, split-ups, relocations, change in management, employee layoffs, and budget cuts were obtained from work-unit managers (59% response). RESULTS: There was an excess risk of CVD in the year following change in management (HR 2.04, 95% CI 1.10-3.78) and employee layoff (HR 2.44, 95% CI 1.29-4.59) in the work unit relative to no change. Exposure to any organizational change also suggested increased risk of CVD (HR 1.48, 95% CI 0.91-2.43). Including perceived stress as mediator in the regression models attenuated the point risk estimates only slightly, indicating no important mediation through this psychosocial factor. CONCLUSIONS: Work-unit organizational change may be associated with excess risk of incident CVD among the employees relative to stable workplaces.

Can work-unit social capital buffer the association between workplace violence and long-term sickness absence? A prospective cohort study of healthcare employees.

PURPOSE: To determine the prospective relation between workplace violence and the risk of long-term sickness absence (LTSA), and study if work-unit social capital could buffer this effect. As an explorative analysis, the association between work-unit social capital and workplace violence is also tested. METHODS: The study is based on the Well-being in HospitAL Employees (WHALE) cohort, including healthcare employees in Denmark. The study sample consisted of 30,044 employees nested within 2304 work-units. Exposure to workplace violence and threats of violence during the past 12 months was measured by self-report. Work-unit social capital was computed by aggregating the mean individual responses within work-units. LTSA was defined as one or more episodes of ≥ 29 consecutive sickness absence days initiated within 2 years following baseline. RESULTS: Employees experiencing workplace violence had a higher risk of LTSA (OR = 1.55; 95% CI 1.39-1.72), but there was no evidence in support of work-unit social capital buffering the effect of workplace violence on LTSA (RERI = 0.24; 95%CI: - 0.36 to 0.84; p = 0.12 for multiplicative interaction). High compared to low work-unit social capital was associated with a lower prevalence of workplace violence (OR = 0.47; 95% CI 0.36-0.61). CONCLUSION: There was a prospective association between workplace violence and LTSA, but work-unit social capital did not buffer this effect. Furthermore, the results revealed an inverse association between work-unit social capital and workplace violence. The findings indicate that  in order to effectively reduce LTSA, preventive interventions need to both prevent workplace violence and strengthen social capital.

Study protocol of the Healthy High School study: a school-based intervention to improve well-being among high school students in Denmark.

BACKGROUND: The prevalence of low well-being, perceived stress and unhealthy behaviours is high among high school students, but few interventions have addressed these problems. The aim of this paper is to present a study protocol of a cluster randomised controlled trial evaluating the Healthy High School (HHS) intervention programme. The intervention programme is designed to improve well-being (primary outcome) by preventing 1) stress and promoting 2) sleep, 3) sense of community, 4) physical activity (PA) and 5) regular and healthy meals among high school students in Denmark. METHODS: The development of the HHS study was guided by the Intervention Mapping protocol. The intervention comprises four components: 1) a teaching material, 2) a smartphone app, 3) a catalogue focusing on environmental changes, and 4) a peer-led innovation workshop aiming at inspiring students to initiate and participate in various movement activities. The HHS study employs a cluster-randomised controlled trial design. Thirty-one high schools across Denmark were randomly allocated to intervention (16 schools) or control (15 schools) groups. The study included all first-year students (~ 16 years of age) (n = 5976 students). Timeline: Intervention: August 2016 - June 2017. Collection of questionnaire data: Baseline (August 2016), 1st follow-up (May 2017) and 2nd follow-up (April 2018). All students were invited to participate in a monthly sub-study about perceived stress using text messages for data collection (September 2016 - June 2017). PA was objectively assessed among a sub-sample of students using accelerometers (Axivity, AX3) in August 2016 and May 2017. PRIMARY OUTCOME MEASURES: Student well-being measured by the Cantril Ladder and the five item World Health Organisation Well-being Index (individual level outcomes). SECONDARY OUTCOME MEASURES: Stress (10-item Perceived Stress Scale), sleep (quantity and quality), PA (hours of moderate-to-vigorous PA per week, hours of daily sedentary time and average daily PA), meal habits (daily intake of breakfast, lunch, snacks and water), and strong sense of community in class and at school, respectively (individual level outcomes). The study encompasses process and effect evaluation as well as health economic analyses. TRIAL REGISTRATION: ISRCTN ISRCTN43284296, 28 April 2017, retrospectively registered.

Psychosocial working conditions and depressive disorder: disentangling effects of job control from socioeconomic status using a life-course approach.

PURPOSE: Job control, the combination of skill discretion and decision authority, is considered a central component of the psychosocial working environment. This longitudinal study examines the relation between job control and risk of incident depressive disorder using a life-course approach. METHODS: We analyze data from The Danish Work Life Course Cohort study, including all Danish individuals aged 15-30 who entered the Danish labor market during 1995-2009 and were free from depressive disorder at entry (955,573 individuals). We measured job control using a job exposure matrix. Depressive disorders were measured using information from nationwide registers of psychiatric in- and outpatient admissions. Using Cox regression models we estimated the prospective association between job control and risk of incident depressive disorders. Analyses accounted for a range of potential confounders prior to workforce entry including socioeconomic status in adolescence and parental psychiatric and somatic diagnoses prior to labor market entry, together with potential confounders in adulthood including income, education, and demographics. RESULTS: Lower levels of past year job control were associated with a higher risk of depressive disorder after adjustment for all covariates (HR = 1.27, 95% CI 1.16-1.38). Results stratified by gender showed associations for both men (HR = 1.38, 95% CI 1.19-1.61) and women (HR = 1.19, 95% CI 1.08-1.32). CONCLUSIONS: Our findings suggest that the level of job control at work affects the risk of clinically diagnosed depressive disorder, and that this association is not due to confounding by socioeconomic status.

Both High and Low Levels of Negative Emotions Are Associated with Higher Blood Pressure: Evidence from Whitehall II Cohort Study.

BACKGROUND: Previous studies of negative emotions and blood pressure (BP) produced mixed findings. Based on the functionalist and evolutionary perspective on emotions, we hypothesized that the association between negative emotions and BP is U-shaped, i.e., that both very high levels of negative emotions and the absence thereof are related to high BP. METHODS: Data from 7479 British civil servants who participated in Phases 1-11 (years 1985-2013) of the Whitehall II cohort study was used. Negative emotions were operationalized as negative affect and depressive and anxiety symptoms. Negative affect was measured at Phases 1 and 2. Anxiety and depressive symptoms were assessed at each phase. BP was measured at every other phase. For each negative emotion measure, an average across all phases was computed and used as a predictor of PB levels throughout the follow-up period using growth curve models. RESULTS: Very high values of anxiety and depressive symptoms, but not negative affect, were associated with higher levels of systolic BP. However, low to moderate levels of all negative emotions were associated with lower blood pressure than the absence of negative emotions. CONCLUSIONS: The article offers a theoretical explanation for a previously observed inverse association between negative emotions and blood pressure and underscores that moderate levels of negative emotions that naturally occur in everyday life are not associated with risks of heightened blood pressure.

Effort-reward imbalance at work and weight changes in a nationwide cohort of workers in Denmark.

OBJECTIVE: To investigate the relation between effort-reward imbalance (ERI) at work and subsequent weight changes. METHODS: We included participants from a population-based cohort of workers in Denmark (mean age = 47 years, 54% women) with two (n = 9005) or three repeated measurements (n = 5710). We investigated the association between (a) ERI (ie, the mismatch between high efforts spent and low rewards received at work) at baseline and weight changes after a 2-year follow-up (defined as ≥5% increase or decrease in body mass index (BMI) vs stable), and (b) onset and remission of ERI and subsequent changes in BMI. Using multinomial logistic regression we calculated risk ratios (RR) and 95% confidence intervals (CI), adjusted for sex, age, education, cohabitation, migration background, and follow-up time. RESULTS: After 2 years, 15% had an increase and 13% a decrease in BMI. Exposure to ERI at baseline yielded RRs of 1.09 (95% CI: 0.95-1.25) and 1.04 (95% CI: 0.90-1.20) for the increase and decrease in BMI, respectively. There were no differences between sex and baseline BMI in stratified analyses. The onset of ERI yielded RRs of 1.04 (95% CI: 0.82-1.31) and 1.15 (95% CI: 0.84-1.57) for subsequent increase and decrease in BMI. The RRs for the remission of ERI and subsequent increase and decrease in BMI were 0.92 (95% CI: 0.71-1.20) and 0.78 (95% CI: 0.53-1.13), respectively. Of the ERI components, high rewards were associated with a lower risk of BMI increase. CONCLUSION: ERI was not a risk factor for weight changes. Future studies may investigate whether this result is generalizable to other occupational cohorts and settings.

Perceived stress and dementia: Results from the Copenhagen city heart study.

Objectives: We investigated if perceived stress in midlife increased the risk of dementia. Furthermore, we explored differences between subgroups related to sex, age and employment status when reporting stress.Methods: In this longitudinal study, we used information on perceived stress from 10,814 participants (mean age 56.7 years). Participants were followed through Danish national registers for development of dementia. Participants were considered at risk of dementia from the date they turned 60 years. Perceived stress was assessed as a combination of self-reported intensity and frequency of stress, and categorized into low (score 0-1), medium (score 2-4), and high stress (score 5-6). We used Poisson regression to estimate incidence rate ratios (IRR) and their 95% confidence intervals (CI) and adjusted for sociodemographic factors and psychiatric morbidity at baseline (main model) as well as cardio/cerebrovascular diseases and health behaviors at baseline (additional model).Results: The mean follow-up time was 13.8 years, and 1,519 participants were registered with dementia. Dementia risk was higher in participants reporting medium stress (IRR = 1.11, 95% CI: 0.99-1.24) and high stress (IRR = 1.36, 95% CI: 1.13-1.65). Adjustment for cardio/cerebrovascular diseases and health behaviors did not alter the results. We did not find strong support for differences between subgroups, although the association between stress and dementia was stronger for those who were employed at the time of reporting high stress.Conclusion: Our results provide empirical support for an effect of perceived stress on the risk of dementia in old age.

Work-unit organisational changes and subsequent prescriptions for psychotropic medication: a longitudinal study among public healthcare employees.

OBJECTIVES: We examined exposure to different types of organisational changes at work as risk factors for subsequent prescription for psychotropic medication among employees. METHODS: The study population included 15 038 public healthcare employees nested within 1284 work units in the Capital Region of Denmark. Multilevel mixed-effects parametric survival models were developed to examine time to prescription for psychotropic medications (anxiolytics/hypnotics/sedatives/antidepressants) during the 12-month interval following exposure to organisational changes relative to no change from January to December 2013. Data on work-unit level organisational changes (including mergers, split-ups, relocation, change in management, employee lay-offs and budget cuts) were collected from work-unit managers (59% response). RESULTS: Any organisational change versus no change was associated with a higher risk of psychotropic prescription (HR: 1.14, 95% CI: 1.02 to 1.26), especially change in management (HR: 1.23, 95% CI: 1.07 to 1.41). Splitting the 12-month follow-up period into two halves yielded particularly high rates of psychotropic prescription in the latter half of the follow-up, for example, any change (HR: 1.25, 95% CI: 1.11 to 1.41), change in management (HR: 1.42, 95% CI: 1.22 to 1.65), mergers (HR: 1.26, 95% CI: 1.06 to 1.50), employee lay-off (HR: 1.23, 95% CI: 1.03 to 1.46) and budget cuts (HR: 1.13, 95% CI: 1.00 to 1.41). The associations did not vary by sex. CONCLUSIONS: Organisational changes in the workplace, especially change in management, may be associated with increased risk of psychotropic prescription among employees regardless of sex.

Multicohort study of change in job strain, poor mental health and incident cardiometabolic disease.

OBJECTIVES: Several recent large-scale studies have indicated a prospective association between job strain and coronary heart disease, stroke and diabetes. Job strain is also associated with poorer mental health, a risk factor for cardiometabolic disease. This study investigates the prospective relationships between change in job strain, poor mental health and cardiometabolic disease, and whether poor mental health is a potential mediator of the relationship between job strain and cardiometabolic disease. METHODS: We used data from five cohort studies from Australia, Finland, Sweden and UK, including 47 757 men and women. Data on job strain across two measurements 1-5 years apart (time 1 (T1)-time 2 (T2)) were used to define increase or decrease in job strain. Poor mental health (symptoms in the top 25% of the distribution of the scales) at T2 was considered a potential mediator in relation to incident cardiometabolic disease, including cardiovascular disease and diabetes, following T2 for a mean of 5-18 years. RESULTS: An increase in job strain was associated with poor mental health (HR 1.56, 95% CI 1.38 to 1.76), and a decrease in job strain was associated with lower risk in women (HR 0.70, 95% CI 0.60-0.84). However, no clear association was observed between poor mental health and incident cardiometabolic disease (HR 1.08, 95% CI 0.96-1.23), nor between increase (HR 1.01, 95% CI 0.90-1.14) and decrease (HR 1.08, 95% CI 0.96-1.22) in job strain and cardiometabolic disease. CONCLUSIONS: The results did not support that change in job strain is a risk factor for cardiometabolic disease and yielded no support for poor mental health as a mediator.