SARS-CoV-2 Infection and Risk of Postacute Psychiatric and Neurologic Diagnoses: A Nationwide Danish Cohort Study.

BACKGROUND AND OBJECTIVES: The extent and burden of postacute psychiatric and neurologic manifestations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are not yet fully understood. To evaluate the association between SARS-CoV-2 infection and postacute manifestations of psychiatric and neurologic disorders, we conducted a nationwide cohort study including the entire Danish population aged 12 years or older on March 1, 2020. METHODS: Individuals were followed up for SARS-CoV-2 infection and diagnosis of subsequent psychiatric and neurologic disorders from March 1, 2020, to January 31, 2023, using the Danish nationwide coronavirus disease 2019 (COVID-19) test surveillance database and the Danish National Patient Registry. The main period of interest was 1-12 months after infection. Incidence rate ratios (IRRs) of new onset of 11 psychiatric and 30 neurologic disorders were calculated by comparing incidence rates of disorders between SARS-CoV-2-positive individuals and individuals without a positive test (nonpositive individuals). Stratified analyses were conducted according to COVID-19 vaccination status, variant period, age, sex, and severity of infection. RESULTS: Overall, 1,775,639 individuals in the study cohort (n = 3,239,008) were tested SARS-CoV-2 positive during follow-up. SARS-CoV-2-positive individuals compared with nonpositive individuals were at 24% reduced risk of any psychiatric disease (IRR 0.76, 95% CI 0.74-0.78) in the postacute period. The risk of any neurologic disorder was slightly higher among SARS-CoV-2-positive individuals than among those without a positive test (IRR 1.05, 95% CI 1.04-1.07). IRRs for specific disorders varied considerably from a 3.9-fold increased risk of change in sense of smell or taste (IRR 3.91, 95% CI 2.77-5.53) to a 29% reduced risk of dementia (IRR 0.71, 95% CI 0.65-0.78). The severity of infection and vaccination status, more so than age, sex, and variant, were found to significantly influence the stratified IRRs. Compared with nonpositive individuals, hospitalized patients with COVID-19 were at a 2.1-fold (IRR 2.05, 95% CI 1.78-2.37) increased risk of psychiatric disorders and at a 2.4-fold increased risk of neurologic disorders (IRR 2.44, 95% CI 2.29-2.60). DISCUSSION: Our study does not support previous findings of substantial postacute neurologic and psychiatric morbidities among the general population of SARS-CoV-2-infected individuals, but does corroborate an elevated risk among the most severe cases with COVID-19.

Association between Salmonella infection and colon cancer: a nationwide registry-based cohort study.

Laboratory data increasingly suggest that Salmonella infection may contribute to colon cancer (CC) development. Here, we examined epidemiologically the potential risk of CC associated with salmonellosis in the human population. We conducted a population-based cohort study using four health registries in Denmark. Person-level demographic data of all residents were linked to laboratory-confirmed non-typhoidal salmonellosis and to CC diagnoses in 1994-2016. Hazard ratios (HRs) for CC (overall/proximal/distal) associated with reported salmonellosis were estimated using Cox proportional hazard models. Potential effects of serovar, age, sex, inflammatory bowel disease and follow-up time post-infection were also assessed. We found no increased risk of CC ≥1 year post-infection (HR 0.99; 95% confidence interval (CI) 0.88-1.13). When stratifying by serovar, there was a significantly increased risk of proximal CC ≥1 year post-infection with serovars other than Enteritidis and Typhimurium (HR 1.40; 95% CI 1.03-1.90). CC risk was significantly increased in the first year post-infection (HR 2.08; 95% CI 1.48-2.93). The association between salmonellosis and CC in the first year post-infection can be explained by increased stool testing around the time of CC diagnosis. The association between proximal CC and non-Enteritidis/non-Typhimurium serovars is unclear and warrants further investigation. Overall, this study provides epidemiological evidence that notified Salmonella infections do not contribute significantly to CC risk in the studied population.

Workplace sexual harassment and depressive symptoms: a cross-sectional multilevel analysis comparing harassment from clients or customers to harassment from other employees amongst 7603 Danish employees from 1041 organizations.

BACKGROUND: Previous research has reported that sexual harassment can lead to reduced mental health. Few studies have focused on sexual harassment conducted by clients or customers, which might occur in person-related occupations such as eldercare work, social work or customer service work. This study examined the cross-sectional association between sexual harassment by clients or customers and depressive symptoms. We also examined if this association was different compared to sexual harassment conducted by a colleague, supervisor or subordinate. Further, we investigated if psychosocial workplace initiatives modified the association between sexual harassment by clients or customers and level of depressive symptoms. METHODS: We used data from the Work Environment and Health in Denmark cohort study (WEHD) and the Work Environment Activities in Danish Workplaces Study (WEADW) collected in 2012. WEHD is based on a random sample of employed individuals aged 18-64. In WEADW, organizational supervisors or employee representatives provided information on workplace characteristics. By combining WEHD and WEADW we included self-reported information on working conditions and health from 7603 employees and supervisors in 1041 organizations within 5 occupations. Data were analyzed using multilevel regression and analyses adjusted for gender, age, occupation and socioeconomic position. RESULTS: Exposure to workplace sexual harassment from clients or customers was statistically significantly associated with a higher level of depressive symptoms (2.05; 95% CI: 0.98-3.12) compared to no exposure. Employees harassed by colleagues, supervisors or subordinates had a higher mean level of depressive symptoms (2.45; 95% CI: 0.57-4.34) than employees harassed by clients or customers. We observed no statistically significant interactions between harassment from clients and customers and any of the examined psychosocial workplace initiatives (all p > 0.05). CONCLUSIONS: The association between sexual harassment and depressive symptoms differed for employees harassed by clients or customers and those harassed by colleagues, supervisors or subordinates. The results underline the importance of investigating sexual harassment from clients or customers and sexual harassment by colleagues, supervisors or subordinates as distinct types of harassment. We found no modification of the association between sexual harassment by clients or customers and depressive symptoms by any of the examined psychosocial workplace initiatives.

Exposure to negative acts and risk of turnover: a study of a register-based outcome among employees in three occupational groups.

PURPOSE: To investigate whether self-reported exposure to negative acts in the workplace (bullying and threats of violence) predicted turnover in three occupational groups (human service and sales workers, office workers and manual workers). METHODS: Survey data on 2766 respondents were combined with data from a national labour force register to assess turnover. Mixed effects logistic regression analysis was used to examine the association between self-reported exposure to negative acts at baseline and risk of turnover after a 1-year follow-up. RESULTS: We found no significant associations between exposure to negative acts (bullying and threats of violence) and risk of turnover. When participants were stratified by occupational group and analyses were adjusted for age, gender, tenure and psychosocial working conditions, we found that exposure to bullying predicted risk of turnover in office workers (OR 2.03, 95 % CI 1.05-3.90), but neither in human service and sales workers, nor in manual workers. The association in office workers lost statistical significance when additionally adjusted for depressive symptoms (OR 1.77, 95 % CI 0.90-3.49). However, in a sensitivity analysis in which we used a 2-year (instead of a 1-year) follow-up period the association between bullying and turnover remained statistically significant in office workers even after adjusting for depressive symptoms (OR 2.10, 95 % CI 1.17-3.76). We found no statistically significant associations between threats of violence and risk of turnover in the stratified analyses. CONCLUSION: Exposure to bullying predicted risk of turnover among office workers but not among human service and sales workers and among manual workers. Threats of violence were not associated with turnover in any occupational group.

Implementation of the Danish return-to-work program: process evaluation of a trial in 21 Danish municipalities.

OBJECTIVES: The aim of this study was to evaluate the implementation of the Danish national return-to-work (RTW) program in 21 Danish municipalities. METHODS: We conducted a structured process evaluation on (i) reach and recruitment, (ii) fidelity, (iii) dose-delivered, (iv) dose-received, and (v) context by formulating 29 implementation criteria and analyzing qualitative and quantitative data from administrative records, interviews, field notes, and questionnaires. RESULTS: All municipalities integrated the basic features of the RTW program into the existing framework of the sickness benefit management system to an acceptable degree, ie, establishment of RTW teams, participation of RTW team members in the training courses, and following the general procedures of the program. However, the level of implementation varied considerably between the municipalities, particularly with respect to fidelity (defined as implementation consistent with the principles of the interdisciplinary RTW process). Five municipalities had high and eight had low fidelity scores. Similar large differences were found with regard to dose-delivered, particularly in the quality of cooperation with beneficiaries, employers, and general practitioners. Only 50% of the first consultations with the RTW coordinator were conducted in time. Among participants who were employed when their sickness absence period started, only 9% had at least one meeting with their workplace. CONCLUSION: It was feasible to implement the basic features of the Danish RTW program, however, large variations existed between municipalities. Establishment of well-functioning interdisciplinary RTW teams might require more time and resources, while ensuring early assessment and more frequent cooperation with employers might need more general adjustments in the Danish sickness benefit system.

Effect of the Danish return-to-work program on long-term sickness absence: results from a randomized controlled trial in three municipalities.

OBJECTIVES: The aim of this study was to evaluate the effect of the Danish return-to-work (RTW) program on long-term sickness absence in a randomized controlled trial in three municipalities. METHODS: The intervention group comprised 1948 participants while the control group comprised 1157 participant receiving ordinary sickness benefit management (OSM). Study participants were working-age adults receiving long-term (≥8 weeks or more) benefits, included regardless of reason for sickness absence or employment status. Each beneficiary was followed-up for a maximum period of 52 weeks. Cox proportional hazards model was used to estimate hazard ratios (HR) for return to work (RTW) with 95% confidence intervals (95% CI). RESULTS: The intervention effect differed significantly between the municipalities (P=0.00005). In one municipality (M2) the intervention resulted in a statistically significant increased rate of recovery from long-term sickness absence (HR 1.51, 95% CI 1.31-1.74). In the other two municipalities, the intervention did not show a statistically significant effect (HR M11.12, 95% CI 0.97-1.29, and HR M30.80, 95% CI 0.63-1.03, respectively). Adjustment for a series of possible confounders only marginally altered the estimated HR. CONCLUSION: The effect of the intervention differed substantially between the three municipalities, indicating that that contextual factors are of major importance for success or failure of this complex intervention.

Fungi, ß-glucan, and bacteria in nasal lavage of greenhouse workers and their relation to occupational exposure.

The nose and mouth are the first regions of the respiratory tract in contact with airborne microorganisms. Occupational exposures to airborne microorganisms are associated with inflammation and different symptoms of the airways. The purpose of this study is to investigate the relation between occupational exposure to fungi, ß-glucan, and bacteria and contents of fungi, ß-glucan, and bacteria in nasal lavage (NAL) of greenhouse workers. We also studied whether contents of microorganisms in NAL were related to gender, time of the work week, and runny nose. NAL samples (n = 135) were taken Monday morning and Thursday at noon and personal exposure to inhalable bioaerosols was measured during a working day. The content of fungi and ß-glucan in NAL of men was affected by their exposure to fungi and ß-glucan. The content of fungi, ß-glucan, and bacteria in NAL was higher Thursday at noon than Monday morning. The ratios of fungi in NAL between Thursday at noon and Monday morning were 14 (median value) for men and 3.5 for women. Gender had no effect on the exposure level but had a significant effect on the content of fungi, ß-glucan, and bacteria in NAL, with the highest contents in NAL of men. On Thursdays, the median content of fungi in NAL samples of men without runny noses was 9408 cfu per NAL sample, whereas the same content for women was 595 cfu per NAL sample. Workers with runny noses had fewer fungi in NAL than workers without runny noses. A higher content of ß-glucan per fungal spore was found in NAL than in the air. This indicates that mainly the larger fungal spores or pollen grains deposit in the nose. The difference between genders and the fact that the content of fungi in NAL was significantly affected by the exposure indicate that the two genders are affected by the same exposure level differently.

Implementation of physical coordination training and cognitive behavioural training interventions at cleaning workplaces--secondary analyses of a randomised controlled trial.

This study evaluates the implementation of physical coordination training (PCT) and cognitive behavioural training (CBTr) interventions in a randomised controlled trial at nine cleaners' workplaces. Female cleaners (n = 294) were randomised into a PCT, a CBTr or a reference (REF) group. Both 12-week interventions were performed in groups guided by an instructor. Records were kept on intervention dose (adherence) unanticipated events at the work place (context) and quality of intervention delivery (fidelity). Participant adherence was 37% in the PCT and 49% in the CBTr interventions. Optimal implementation was reached by only 6% in PCT and 42% in the CBTr. Analysis of the barriers to successful implementation indicated that the intervention process is sensitive to unanticipated events. In order to succeed in improving the health of high-risk populations such as cleaners and to correctly interpret intervention effects, more research on implementation is needed. TRIAL REGISTRATION: ISRCTN96241850. PRACTITIONER SUMMARY: Both physical coordination training and cognitive behavioural training are potential effective workplace interventions among low educated job groups with high physical work demands. However, thorough consideration should be given to feasibility in the design of interventions. The optimal intervention should be tailored to closely match the implementation context and be robust and flexible to minimise susceptibility to changes in work organisation.

The relationship between low back pain and leisure time physical activity in a working population of cleaners--a study with weekly follow-ups for 1 year.

BACKGROUND: Low back pain (LBP) and leisure time physical activity (LTPA) are considered to be closely related, and clinical guidelines for the treatment of acute LBP recommend patients stay physically active. However, the documentation for this recommendation is sparse and based on studies involving patient populations. The purpose of the study was (1) to investigate the correlation between LBP and LTPA on a weekly basis over the course of a year in a high-risk group of cleaners; and (2) to investigate if maintaining LTPA during an episode of acute LBP has a positive effect on LBP intensity in the subsequent 4 weeks. METHODS: 188 cleaners consented to participate in a 52-week text message survey about hours of LTPA and intensity of LBP (from 0 to 9) over the previous 7 days. The correlation between LBP and LTPA was calculated by Pearson correlation coefficient. During an episode of acute LBP, a mixed effect logistic regression model was used to investigate whether cleaners who maintain LTPA have a lower pain intensity and higher probability of returning to initial pain intensity within the following four weeks compared with cleaners who decrease LTPA during acute LBP. RESULTS: The correlation between weekly LTPA and LBP data was negative, but numerically low (r = -0.069) and statistically insignificant (p = 0.08). Among the 82 cleaners experiencing at least one episode of acute LBP, those maintaining LTPA during an episode of acute LBP did not have a lower pain intensity (average LBP intensity difference between groups of 0.06; 95% confidence interval (95% CI) of -0.417 to 0.539) or higher probability of returning to initial pain level (Odds ratio 1,02; 95% CI of 0.50 to 2.09) in the following four weeks compared with cleaners decreasing LTPA during acute LBP. CONCLUSIONS: Hours of LTPA and intensity of LBP measured on a weekly basis throughout a year showed no close correlation. Maintaining LTPA during an episode of acute LBP did not result in a positive effect on LBP in the following 4 weeks. Documentation of LTPA recommendations for acute LBP in working populations is still needed.

The Danish national return-to-work program--aims, content, and design of the process and effect evaluation.

The Danish national return-to-work (RTW) program aims to improve the management of municipal sickness benefit in Denmark. A study is currently ongoing to evaluate the RTW program. The purpose of this article is to describe the study protocol. The program includes 21 municipalities encompassing approximately 19 500 working-age adults on long-term sickness absence, regardless of reason for sickness absence or employment status. It consists of three core elements: (i) establishment of multidisciplinary RTW teams, (ii) introduction of standardized workability assessments and sickness absence management procedures, and (iii) a comprehensive training course for the RTW teams. The effect evaluation is based on a parallel group randomized trial and a stratified cluster controlled trial and focuses on register-based primary outcomes - duration of sickness absence and RTW - and questionnaire-based secondary outcomes such as health and workability. The process evaluation utilizes questionnaires, interviews, and municipal data. The effect evaluation tests whether participants in the intervention have a (i) shorter duration of full-time sickness absence, (ii) longer time until recurrent long-term sickness absence, (iii) faster full RTW, (iv) more positive development in health, workability, pain, and sleep; it also tests whether the program is cost-effective. The process evaluation investigates: (i) whether the expected target population is reached; (ii) if the program is implemented as intended; (iii) how the beneficiaries, the RTW teams, and the external stakeholders experience the program; and (iv) whether contextual factors influenced the implementation. The program has the potential to contribute markedly to lowering human and economic costs and increasing labor force supply. First results will be available in 2013. The trial registrations are ISRCTN43004323, and ISRCTN51445682.

Occupational physical activity and mortality among Danish workers.

PURPOSE: The relationship between occupational physical activity (OPA) and mortality has mainly been studied among males and shows conflicting results. This study examines this relationship in a cohort of both male and female workers. METHODS: OPA was determined by 4 self-reported questions in a representative sample of 5,839 Danish workers aged 18-59 years at baseline. A 19-year follow-up on mortality was assessed by linkage with the national death registry. Gender-stratified Cox regression models were used to determine the effect of high OPA on all-cause mortality while controlling for age, BMI, smoking, alcohol consumption, doctor-diagnosed disease, influence at work, and social class. RESULTS: Two hundred and sixty-two males (8.6%) and 174 females (6.2%) died during follow-up. Being in the highest quartile of OPA predicted an increased risk for all-cause mortality among male workers (HR: 1.79, CI: 1.19-2.70), but not among female workers (HR: 0.99, CI: 0.65-1.49) compared with workers in the lowest quartile of OPA. Among females, indications of a u-shaped relationship between occupational physical activity and all-cause mortality were found. CONCLUSIONS: The findings indicate that high occupational physical activity increases the risk for all-cause mortality among male workers. Future studies need to further examine gender differences in the effects of OPA on mortality.

Effects on musculoskeletal pain, work ability and sickness absence in a 1-year randomised controlled trial among cleaners.

BACKGROUND: Only a few workplace initiatives among cleaners have been reported, even though they constitute a job group in great need of health promotion. The purpose of this trial was to evaluate the effect of either physical coordination training or cognitive behavioural training on musculoskeletal pain, work ability and sickness absence among cleaners. METHODS: A cluster-randomised controlled trial was conducted among 294 female cleaners allocated to either physical coordination training (PCT), cognitive behavioural training (CBTr) or a reference group (REF). Questionnaires about musculoskeletal pain and work ability were completed at baseline and after one year's intervention. Sickness absence data were obtained from the managers' records. Analyses were performed according to the intention-to-treat-principle (ITT). RESULTS: No overall reduction in musculoskeletal pain, work ability or sickness absence from either PCT or CBTr compared with REF was found in conservative ITT analyses. However, explorative analyses revealed a treatment effect for musculoskeletal pain of the PCT. People with chronic neck/shoulder pain at baseline were more frequently non-chronic at follow-up after PCT compared with REF (p = 0.05). CONCLUSIONS: The PCT intervention appeared effective for reducing chronic neck/shoulder pain among the female cleaners. It is recommended that future interventions among similar high-risk job groups focus on the implementation aspects of the interventions to maximise outcomes more distal from the intervention such as work ability and sickness absence. TRIAL REGISTRATION: ISRCTN: ISRCTN96241850.

Direct and indirect effects in a survival context.

A cornerstone of epidemiologic research is to understand the causal pathways from an exposure to an outcome. Mediation analysis based on counterfactuals is an important tool when addressing such questions. However, none of the existing techniques for formal mediation analysis can be applied to survival data. This is a severe shortcoming, as many epidemiologic questions can be addressed only with censored survival data. A solution has been to use a number of Cox models (with and without the potential mediator), but this approach does not allow a causal interpretation and is not mathematically consistent. In this paper, we propose a simple measure of mediation in a survival setting. The measure is based on counterfactuals, and measures the natural direct and indirect effects. The method allows a causal interpretation of the mediated effect (in terms of additional cases per unit of time) and is mathematically consistent. The technique is illustrated by analyzing socioeconomic status, work environment, and long-term sickness absence. A detailed implementation guide is included in an online eAppendix (http://links.lww.com/EDE/A476).

Prognostic factors for long-term sickness absence among employees with neck-shoulder and low-back pain.

OBJECTIVE: The aim of this study was to identify prognostic factors for long-term sickness absence among employees with neck-shoulder or low-back pain. METHODS: In 2000, a representative sample of Danish employees (N=5036) rated their average pain intensity in the neck-shoulder and low-back during the last three months on a 10-point scale; using a questionnaire, they also reported on physical and psychosocial work factors, health behavior, work ability and self-efficacy. Employees reporting pain intensity of >or=4 were considered to have musculoskeletal pain. As a result, we defined two populations to be included in our analyses: people with pain in the neck-shoulder (N=848) and low-back (N=676) regions. Data on long-term sickness absence of >or=3 weeks for the period 2001-2002 were attained from the Danish national register of social transfer payments. RESULTS: One fifth of employees with neck-shoulder and low-back pain experienced long-term sickness absence during the two-year follow-up. Among employees with neck-shoulder and low-back pain, respectively, the main significant risk factors were (i) pain intensity [hazard ratio (HR)=1.12, 95% confidence interval (95% CI) 1.02-1.24 and HR=1.13, 95% CI 1.01-1.26] and (ii) heavy physical work (HR=1.68, 95% CI 1.21-2.33 and HR=1.41 95% CI 1.00-2.01). CONCLUSION: Preventive initiatives for long-term sickness absence should aim to reduce pain intensity and heavy physical work among employees with neck-shoulder and low-back pain.