Mental illness rates among employees with fixed-term versus permanent employment contracts: a Danish cohort study.

PURPOSE: It has been hypothesized that employment in a fixed-term instead of permanent contract position is associated with an increased risk of development of mental health problems. The present study aimed at estimating rate ratios between fixed-term and permanent employees in the Danish labor force, for use of psychotropic drugs and psychiatric hospital treatment due to mood, anxiety or stress-related disorders, respectively. METHODS: Employment data were drawn from the Danish Labor Force Survey of 2001-2013, which is a part of the European Labor Force Survey. Full-time employed survey participants without mental illness at the baseline interview (N = 106,501) were followed in national health registers for up to 5 years. Poisson regressions were used to estimate rate ratios for redeemed prescriptions of psychotropic drugs and psychiatric hospital treatments due to mood, anxiety or stress-related disease. The analyses were controlled for age, gender, industrial sector, nighttime work, level of education, calendar year, disposable family income and social transfer payments within 1 year prior to the baseline interview. RESULTS: The rate ratio for hospital diagnosed mood, anxiety or stress-related disorders among employees with fixed-term vs. permanent employment contracts was estimated at 1.39 (99.5% CI 1.04-1.86), while the corresponding rate ratio for redeemed prescriptions of psychotropic drugs was estimated at 1.12 (99.5% CI 1.01-1.24). CONCLUSION: The present study supports the hypothesis that employment in a fixed-term rather than permanent contract position is associated with an increased risk of developing mental health problems. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR2-10.2196/24392.

Do baseline industry and job group skill level predict welfare dependency at 1, 3 and 5 years after mental health related sickness absence? A Danish cohort study.

BACKGROUND: The cost of mental ill health in the EU-28 nations has been estimated at approximately 4.1% of the total gross domestic products (GDP). Improved rates of return to sustainable employment among people who are sick-listed due to mental ill health would decrease spending on welfare benefits. The present cohort study provides statistical information that may be helpful in the design and prioritizing of efforts aimed at reducing the burden of sickness absence due to mental ill health among employees in the general working population of Denmark. Our primary aim was to estimate odds of being i) deceased or recipient of health related welfare benefits and ii) recipient non-health related welfare benefits, compared to being alive and self-reliant at 1, 3 and 5 years after first visit to a jobs and benefits office due to mental health related sickness absence, as a function of industrial sector and job group skill level at baseline. A secondary aim was to analyze these odds as a function of baseline age, gender, type of mental ill health, family type and employment status. METHODS: The study population consisted of 20-54 year-old persons on long-term sickness absence due to mental health problems in 21 Danish municipalities in 2010-2012 (N = 19,660). Odds ratios were estimated by use of multinomial logistic regression. The outcomes were ascertained through national registers. RESULTS: We did not find any statistically significant association between baseline industrial sector or job group skill level and welfare dependency at follow-up. In the secondary analyses, the estimated odds of health and non-health related welfare dependencies at follow-up tended to increase with unemployment, age, being single and being on sick leave due to self-reported anxiety or depression versus stress/burnout at baseline. CONCLUSIONS: The present study does not support that industry and job group skill level predict welfare dependency after health related sickness absence, after adjustment for relevant covariates, in the general population of Denmark. It suggests, however, that the vulnerability lies in population groups characterized by unemployment, older age, being single and being on sick leave due to self-reported anxiety or depression versus stress/burnout.

Fixed-term contract positions, unemployment and mental ill health: a Danish cohort study.

BACKGROUND: Both perceived job insecurity and unemployment has been associated with an increased risk of developing mental ill health. It has, moreover, been proposed that an insecure employment may be as detrimental as unemployment itself. OBJECTIVE: To estimate incidence rate ratios (RRs) of (i) redeemed prescriptions for psychotropic drugs and (ii) psychiatric hospital treatment due to mood, anxiety, or stress-related disease, among fixed-term contract workers (as an operationalization of insecure job) vs. unemployed, in the general population of Denmark. METHODS: Data on baseline employment status were drawn from the Danish Labor Force Surveys in the years 2001-2013. Participants (10,265 fixed-term contract workers and 7926 unemployed) were followed for up to 5 years in national registers (2439 cases of psychotropic drug use, 71,516 person years; 311 cases of psychiatric hospital treatment, 86,790 person years). Adjusted RRs were obtained by Poisson regression. We aspired to minimize health selection effects by (i) exclusion of survey participants who received sickness benefits, social security cash benefits, psychiatric hospital treatment or a prescription for psychotropic drugs, within 1-year prior to baseline (n = 11,693), (ii) adjustment for age, gender, level of education, calendar year, disposable family income and maternity/paternity benefits within 1-year prior to baseline. RESULTS: The adjusted RR for fixed-term contract workers vs. unemployed was 0.98 (99.5% CI: 0.87-1.11) for psychotropic drugs and 0.93 (99.5% CI: 0.67-1.30) for psychiatric hospital treatment. CONCLUSION: The present study did not find significant differences in the risk of developing mental ill health between fixed-term contract workers and unemployed, and thus suggests that fixed-term contracts may be as detrimental as unemployment. TRIAL REGISTRATION: International Registered Report Identifier (IRRID): DERR2-10.2196/24392.

Musculoskeletal pain as a predictor for depression in the general working population of Denmark.

Aim: This study examines the association between musculoskeletal complaints and subsequent use of antidepressants and/or psychiatric hospital treatment for depressive mood disorders in the Danish labour force. Methods: The study is based on two cohorts. The first cohort is the total labour force in 21 Danish municipalities (n=693,860), where the risk of depression (psychiatric diagnosis or antidepressant treatment) during 2010-2015 was compared between individuals on long-term sickness absence due to musculoskeletal disorders (MSD) and non-sick-listed gainfully employed individuals. The second cohort is a random sample of the Danish labour force (n=9248) who were followed during 2011-2015 to estimate the association between self-rated musculoskeletal pain and depression. All analyses were controlled for age, sex, calendar period and socio-economic status. Results: Compared to non-sick-listed gainfully employed individuals, there was an increased risk of depression in individuals sick-listed with MSD, with rate ratios of 2.39 (99% confidence interval (CI) 2.22-2.58) for individuals with less severe MSD and 4.27 (99% CI 3.98-4.59) for individuals with more severe MSD. There was also an increased risk of depression associated with self-rated pain (yes vs. no), with a rate ratio of 2.17 (99% CI 1.69-2.78). The population attributable fraction of depression from musculoskeletal pain was 0.35 (99% CI 0.24-0.45). Conclusions: The results of the present study indicate that musculoskeletal pain is an important predictor of indicators of depression in the general working population of Denmark.

Occupational lifting and risk of hypertension, stratified by use of anti-hypertensives and age - a cross-sectional and prospective cohort study.

BACKGROUND: Heavy occupational lifting is prevalent in the general working population and is sparsely reported to associate with hypertension, especially among older and hypertensive workers. We investigated if heavy occupational lifting is associated with hypertension and blood pressure (BP) in both cross-sectional and prospective study designs in the Copenhagen General Population Study, stratified by age, and use of anti-hypertensives. METHODS: Participation was conducted following the declaration of Helsinki and approved by the ethical committee (H-KF-01-144/01). By multivariable logistic and linear regression models, we investigated the association between heavy occupational lifting and hypertension, in a cross-sectional design (n = 67,363), using anti-hypertensives or BP ≥140/≥90 mmHg as outcome, and in a prospective design (n = 7020) with an above-median change in systolic BP (SBP) from baseline to follow-up and/or a shift from no use to use of anti-hypertensives as outcome, with and without stratification by age and use of anti-hypertensives. RESULTS: The odds ratio for hypertension was estimated at 0.97 (99% CI: 0.93-1.00) in the cross-sectional analysis, and at 1.08 (99% CI: 0.98-1.19) in the prospective analysis. The difference in SBP among workers with versus without heavy occupational lifting was estimated at - 0.29 mmHg (99% CI -0.82 - 0.25) in the cross-sectional and at 1.02 mmHg (99% CI -0.41 - 2.45) in the prospective analysis. No significant interaction between heavy occupational lifting and age, nor use of anti-hypertensives were shown. CONCLUSIONS: Only the prospective analysis indicated heavy occupational lifting to increase the risk of hypertension. Further research on the association between occupational lifting and hypertension are needed.

Night work and risk of ischaemic heart disease and anti-hypertensive drug use: a cohort study of 145 861 Danish employees.

BACKGROUND: Ischaemic heart disease (IHD) and hypertension are leading causes of mortality and night work has been suspected as a risk factor. Meta-analyses and previous studies are often limited by power and various definitions of exposure and outcomes. This study aimed to investigate if night work increases the risk of IHD or anti-hypertensive drug usage in a large cohort of Danish employees. METHODS: Individual participant data on night work were drawn from the Danish Labour Force Survey (1999-2013). We included 145 861 participants (53% men) 21-59 years of age working 32 h or more per week. Participants with diagnosis or drug use in the year prior to baseline were excluded. Data on outcomes were obtained from nationwide health registers. Using Poisson regression we analyzed incidence rates of the outcomes as functions of night work adjusted for relevant covariates. RESULTS: We observed 3635 cases of IHD and 20 648 cases used anti-hypertensive drugs. When examining main effects the association of night work with drug use was estimated at rate ratio (RR): 1.05 (95% CI: 1.01-1.09). A sensitivity analysis suggested a dose-response association. The association of night work with IHD was estimated at RR: 1.08 (95% CI: 0.98-1.19). Overall likelihood ratio test showed no statistically significant associations between night work and IHD or drug use when including interactions with sex and socioeconomic status. CONCLUSIONS: Night work was associated with an increased risk of anti-hypertensive drug use. Small estimates suggested a dose-response association. No statistically significant association between night work and IHD were found.

Night-time work and all-cause mortality in the general working population of Denmark.

PURPOSE: A recent study among female nurses in Denmark found an increased mortality among night-time workers, which has raised concerns about the sufficiency of the EU Working Time Directive. The aim of the present study was to examine the relationship between night-time work and all-cause mortality among full-time employees in the general workforce of Denmark. METHODS: Interview data from the Danish Labour Force Surveys, 1999-2013, were linked to national registers with individual-level data on occupation, industry, socioeconomic status (SES), emigrations and deaths. The participants (N = 159,933) were followed from the end of the calendar year of the interview until the end of 2014. Poisson regression was used to estimate rate ratios for all-cause mortality, with and without stratification by sex and socioeconomic status. A likelihood ratio test was used to test the overall null-hypothesis, which stated that the mortality rates were independent of night-time work, SES × night-time work and sex × night-time work. RESULTS: The likelihood ratio test did not reject the null hypothesis (p = 0.14). The rate ratio for all-cause mortality among employees with vs. without night-time work was estimated at 1.07 (95% CI 0.97-1.19) after adjustment for age, sex, SES, calendar time, weekly working hours and time passed since the start of follow-up. CONCLUSIONS: The present study did not find any statistically significant associations between night-time work and all-cause mortality among employees in the general workforce of Denmark.

Long working hours and stroke among employees in the general workforce of Denmark.

AIMS: A systematic review and meta-analysis have found that long working hours were prospectively associated with an increased risk of overall stroke. The primary aim of the present study was to test if this finding could be reproduced in a sample that has been randomly selected from the general workforce of Denmark. A secondary aim was to estimate the association for haemorrhagic and ischaemic stroke separately. METHODS: Individual participant data on 20- to 64-year-old employees were drawn from the Danish Labour Force Survey, 1999-2013, and linked to data on socio-economic status (SES), migrations, hospitalisations and deaths from national registers. The participants were followed from the time of the interview until the end of 2014. Poisson regression was used to estimate age-, sex- and SES-adjusted rate ratios for stroke as a function of weekly working hours. RESULTS: With 35-40 working hours per week as reference, the estimated rate ratios for overall stroke were 0.97 (95% confidence interval (CI) 0.83-1.13) for 41-48 working hours, 1.10 (95% CI 0.86-1.39) for 49-54 working hours and 0.89 (95% CI 0.69-1.16) for ≥55 working hours. The estimated rate ratios per one category increase in working hours were 0.99 (95% CI 0.93-1.06) for overall stroke, 0.96 (95% CI 0.88-1.05) for ischaemic stroke and 1.15 (95% CI 1.02-1.31) for haemorrhagic stroke. CONCLUSIONS: Our analysis does not support the hypothesis that long working hours are associated with increased rates of overall stroke. It suggests, however, that long working hours might be associated with increased rates of haemorrhagic stroke.

Working hours and all-cause mortality in relation to the EU Working Time Directive: a Danish cohort study.

Background: In keeping with the need to protect the safety and health of workers, the EU Working Time Directive stipulates that a worker's average working time for each 7-day period, including overtime, does not exceed 48 h. It has, however, not been settled whether or not the threshold at 48 working hours a week is low enough to protect against excess mortality from long work weeks. The aim of the present study was to examine all-cause mortality in relation to weekly working hours among employees in the general population of Denmark. A special attention was given to mortality rates among employees with moderately long work weeks, 41-48 h. Methods: Interview data from cohorts of 20-64 year-old employees were drawn from the Danish Labour Force Survey. The participants (N = 159 933) were followed through national registers from the end of the calendar year of the interview (1999-2013) until the end of 2014. Rate ratios (RRs) for all-cause mortality were estimated as a function of weekly working hours while controlling for age, sex, social class, night-time work and calendar year. Results: We found 3374 deaths during an average follow-up time of 7.7 years. With 32-40 working hours a week as reference, the RRs for all-cause mortality were 0.75 (95% CI: 0.66-0.85) for 41-48 and 0.92 (0.80-1.05) for >48 h. Conclusion: Mortality rates in Denmark are significantly lower among employees with moderately long work weeks than they are among full-time employees without overtime work.

Heavy lifting at work and risk of retinal detachment: a population-based register study in Denmark.

OBJECTIVES: To investigate the relationship between rhegmatogenous retinal detachment (RRD) and frequent heavy lifting in a Danish working population through national register data. METHODS: A dynamic cohort of all men aged 20-59 years in Denmark was followed through the Danish Occupational Hospitalisation Register from 1995 to 2010 for diagnosed RRD. Occupational categories were classified according to their potential for heavy lifting in 4 main groups: heavy lifters, manual workers unlikely to be heavy lifters, other manual workers and non-manual workers unlikely to be heavy lifters. The age-standardised rate of diagnosed RRD for heavy lifting occupations was compared with that experienced by the other 3 occupational categories. Rate ratios (RRs) and 95% CIs were estimated through a Poisson regression model adjusted for calendar period and age group. RESULTS: The highest age-standardised rate of diagnosed RRD was recorded among non-manual workers performing occupational activities unlikely to be associated with heavy lifting (18.0 cases per 100,000 person-years). The RR for workers in jobs expected to entail a high frequency of heavy lifting compared with manual workers whose occupation was unlikely to be associated with heavy lifting was 0.91 (95% CI 0.73 to 1.14), while in comparison with other manual workers, it was 0.93 (95% CI 0.78 to 1.11). The RR compared with non-manual workers in occupations unlikely to entail heavy lifting was 0.51 (95% CI 0.43 to 0.60). CONCLUSIONS: These findings do not support an association of occupational heavy lifting with diagnosed RRD. The epidemiological evidence for this association is still inconclusive. Future studies should use a more specific measure of exposure to resolve the outstanding uncertainties.

Temporal changes in occupational sitting time in the Danish workforce and associations with all-cause mortality: results from the Danish work environment cohort study.

BACKGROUND: Prolonged sitting has been negatively associated with a range of non-communicably diseases. However, the role of occupational sitting is less clear, and little is known on the changes of occupational sitting in a working population over time. The present study aimed to determine 1) temporal changes in occupational sitting time between 1990 and 2010 in the Danish workforce; 2) the association and possible dose-response relationship between occupational sitting time and all-cause mortality. METHODS: This study analysed data from the Danish Work Environment Cohort Study (DWECS), which is a cohort study of the Danish working population conducted in five yearly intervals between 1990 and 2010. Occupational sitting time is self-reported in the DWECS. To determine the association with all-cause mortality, the DWECS was linked to the Danish Register of Causes of Death via the Central Person Register. RESULTS: Between 1990 and 2010 the proportion of the Danish workforce who sat for at least three quarters of their work time gradually increased from 33.1 to 39.1%. All-cause mortality analyses were performed with 149,773 person-years of observation and an average follow-up of 12.61 years, during which 533 deaths were registered. None of the presented analyses found a statistically significant association between occupational sitting time and all-cause mortality. The hazard ratio for all-cause mortality was 0.97 (95% CI: 0.79; 1.18) when ≥24 hr/wk occupational sitting time was compared to <24 hr/wk for the 1990-2005 waves. CONCLUSIONS: Occupational sitting time increased by 18% in the Danish workforce, which seemed to be limited to people with high socio-economic status. If this increase is accompanied by increases in total sitting time, this development has serious public health implications, given the detrimental associations between total sitting time and mortality. The current study was inconclusive on the specific role that occupational sitting might play in the increased all-cause mortality risk associated with the total volume of sitting.

Association of perceived job insecurity with ischemic heart disease and antihypertensive medication in the Danish Work Environment Cohort Study 1990-2010.

PURPOSE: To determine the effect of job insecurity based on repeated measurements on ischemic heart disease (IHD) and on antihypertensive medication. METHODS: The study population consists of 12,559 employees aged 18-59 years of the Danish Work Environment Cohort Study. With an open cohort design, data from up to four representative waves were linked to four registers. Poisson regression with time-dependent covariates was used to estimate the rate ratio (RR) with confidence interval (CI) of perceived job insecurity associated with first-time IHD hospitalization or mortality 1991-2010 (n = 561 cases) and incident dispensing of prescribed antihypertensive medications 1996-2010 (n = 2,402 cases). RESULTS: Participants with perceived job insecurity filled more antihypertensive prescriptions (age-, gender-, and calendar year-adjusted RR 1.23, 95 % CI 1.12-1.33) and had a borderline significant higher IHD incidence (RR 1.23, 95 % CI 0.98-1.55). In a subanalysis, the risk of antihypertensive medication dispensed was only significant among employees with worries about both unemployment and poor reemployment opportunities. After explorative stratifications by age, gender, and occupational status, perceived job insecurity was associated with more dispensing of antihypertensive medications to participants less than 50 years of age. CONCLUSIONS: In a country with high social security and active labor market policy, employees with the feeling of an insecure job have a modestly increased risk to fill an antihypertensive prescription. Further studies on health risks of job insecurity should consider improved exposure assessment, earlier outcomes such as medication in order to increase statistical power, and identification of vulnerable population groups.

A prospective study of occupational status and disability retirement among employees with diabetes in Denmark.

The aim of this study was to examine the extent and distribution of disability retirement among people with diabetes in the workforce. Using four population registries, the study examined the relative rates of disability retirement among employees in Denmark over a 10-year period. The findings highlight that the risk of disability retirement increases as occupational status decreases. With an ageing workforce and increasing prevalence of diabetes, it is important to target primary, secondary and tertiary prevention to the groups that need it most in attempts to prolong the working lives of individuals.

Socio-occupational class, region of birth and maternal age: influence on time to detection of cryptorchidism (undescended testes): a Danish nationwide register study.

BACKGROUND: Cryptorchidism (undescended testes) is associated with poor male fertility, but can be alleviated and fertility preserved to some degree by early detection and treatment. Here we assess the influence of socio-occupational class, geographical region, maternal age and birth cohort on time to detection and correction of cryptorchidism. METHODS: All boys born in Denmark, 1981 to 1987 or 1988 to 1994, with a diagnosis of cryptorchidism were identified in nationwide registers. The boys were followed for a diagnosis until their 16th birthday. The age at first diagnosis was noted and used as proxy for time to detection of cryptorchidism. Parental employment in the calendar year preceding birth was grouped into one of five socio-occupational classes. Geographical region was defined by place of birth in one of 15 Danish counties. Detection rate ratios of cryptorchidism were analyzed as a function of parental socio-occupational group, county, maternal age and birth cohort by use of Poisson regression. RESULTS: Some 6,059 boys in the early and 5,947 boys in the late cohort received a diagnosis of cryptorchidism. Time to detection was independent of parental socio-occupational group and maternal age but differed slightly between geographical regions. A similar pattern was obtained for surgical correction after a diagnosis. Age at diagnosis decreased by 2.7 years from the early to the late cohort. CONCLUSIONS: These results indicate that childhood socio-occupational inequality in detection and correction of cryptorchidism would play a negligible role in male infertility in a life course perspective. Geographical region may have exerted some influence, especially for the oldest cohort.

Psychosocial job strain and risk of adverse birth outcomes: a study within the Danish national birth cohort.

OBJECTIVE: A number of studies examined the effects of prenatal stress on birth outcomes with diverging and inconclusive results. We aimed to examine if working with high job strain during pregnancy measured in week 16 was associated with risk of giving birth to a child born preterm or small/large for gestational age (SGA/LGA), and second, if social support affected any associations. DESIGN: Study population was 48 890 pregnancies from the Danish National Birth Cohort. Multinomial logistic regression estimated ORs. Covariates included: maternal age, BMI, parity, exercise, smoking, alcohol and coffee consumption, manual work, serious maternal disease, parental height and gestational age at interview. In accordance with Good Epidemiological Practice, a protocol outlined the study design before analyses were initiated. RESULTS: High job strain was associated with significantly lower odds of being born LGA (OR=0.81, CI 0.70 to 0.92) when compared to low-strain jobs, but no associations between high strain and preterm birth or SGA were found. Stratification by social support showed a non-statistically significant tendency of higher odds of preterm birth when exposed to high strain and low social support. CONCLUSIONS: In spite of the high statistical precision, we did not find any clear association between job strain and preterm birth nor between job strain and SGA.

Enterprise size and return to work after stroke.

INTRODUCTION: It has been hypothesised that return to work rates among sick-listed workers increases with enterprise size. The aim of the present study was to estimate the effect of enterprise size on the odds of returning to work among previously employed stroke patients in Denmark, 2000-2006. METHODS: We used a prospective design with a 2 year follow-up period. The study population consisted of 13,178 stroke patients divided into four enterprise sizes categories, according to the place of their employment prior to the stroke: micro (1-9 employees), small (10-49 employees), medium (50-249 employees) and large (>250 employees). The analysis was based on nationwide data on enterprise size from Statistics Denmark merged with data from the Danish occupational hospitalisation register. RESULTS: We found a statistically significant association (p = 0.034); each increase in enterprise size category was followed by an increase in the estimated odds of returning to work. CONCLUSIONS: The chances of returning to work after stroke increases as the size of enterprise increases. Preventive efforts and research aimed at finding ways of mitigating the effect are warranted.

Bullying or violence during training and the risk of dropout from the eldercare sector 2 years later.

BACKGROUND: The proportion of old people in need of care is growing rapidly in most western societies, and there is a rising demand for qualified eldercare workers in the years to come. Hence, solutions to high turnover in the eldercare sector are becoming increasingly important. AIM: To test whether bullying, violence and/or threats of violence (violence) among health care trainees are predictors of subsequent dropout from the eldercare sector 2 years after graduation from college. METHODS: A questionnaire was given to all health care trainees in Denmark approximately 2 weeks before their graduation in 2004. Female respondents (N = 5000) were followed in national employment registers to see whether they had dropped out of the eldercare sector by the end of 2006. Logistic regression was used to model the outcome. RESULTS: Among the respondents, 5.5% had been bullied during the training period, 9.1% had been subjected to violence. Hereof, 1% reported exposure to both bullying and violence. At follow-up, 37% had dropped out of the eldercare sector. The odds of dropout were significantly associated with bullying, OR = 1.39 (95% CI: 1.08-1.79), but not with violence, OR = 0.89 (95% CI: 0.72-1.09). CONCLUSION: Being bullied while in training as a health care worker is a predictor of subsequent dropout from the eldercare sector.

Night-shift work and psychiatric treatment. A follow-up study among employees in Denmark.

OBJECTIVES: We aimed to test the hypotheses that night-shift work is associated with an increased incidence of (i) redeemed prescriptions for psychotropic medicine and (ii) psychiatric hospital treatment due to mood, anxiety or stress-related disease. Moreover, we aimed to assess whether (iii) the effect of night-shift work on the rates of antidepressants differs from the effects on the rates of anxiolytics and (iv) the association between night-shift work and psychotropic medicine is affected by long working hours. METHODS: Full-time employees who participated in the Danish Labor Force Survey sometime in the period 2000-2013 (N=131 321) were followed for up to five years in national registers for redeemed prescriptions and psychiatric hospital treatment. The analyses were controlled for sex, age, weekly working hours, calendar time of the interview and socioeconomic status. RESULTS: We detected 15 826 cases of psychotropic drug use in 521 976 person-years at risk and 1480 cases of hospitalization in 636 673 person-years at risk. The rate ratio (RR) for psychotropic drugs was estimated to be 1.09 [99% confidence interval (CI) 1.02-1.16] for night-shift versus no night-shift work. The corresponding RR for psychiatric hospital treatment was 1.11 (95% CI 0.95-1.29). The odds of redeeming a prescription for antidepressants rather than anxiolytics was independent of night-shift work: 1.09 (95% CI 0.96-1.24), and we found no interaction effect between night-shift work and working hours (P=0.26). CONCLUSION: As it appears in the general working population in Denmark, night-shift work is not an important predictor of mental ill health.

Do lifestyle factors and general health predict dropout among recently qualified eldercare workers? A two-year follow-up study.

BACKGROUND: The eldercare sector in Denmark as in many industrialised countries is characterised by difficulties in retaining labour. Research suggests a possible imbalance between lifestyle and health among eldercare trainees and the demanding work encountered as eldercare employees. The aim of the present study was to determine the predictive effect of lifestyle and self-rated health on dropout from the Danish eldercare sector two years after qualification. METHODS: We included 4,526 female eldercare trainees in the analyses of lifestyle parameters and 5,023 in the analyses of self-rated health. The participants in this prospective study were recruited from 27 of the 28 Danish colleges for eldercare. We linked survey data with national register data to obtain information about labour market attachment two years after qualification. RESULTS: The results of the present study showed that the poorer self-rated health, the higher the risk for dropout from the labour market (p < 0.0001). However, the results were less consistent regarding the predictive effect of a detrimental lifestyle. We found that overweight/obesity (p = 0.0021 and p = 0.0012) as well as smoking (p = 0.0017) decreased the risk of dropout from eldercare into education. We found no support for increased likelihood of dropout among physically inactive. CONCLUSIONS: The results of the present study show that a poorer self-rated health is a predictor for dropout, not only from the eldercare two years after qualification, but from the labour market as a whole. However, the results were less consistent regarding the predictive effect of a detrimental lifestyle on dropout.

Industrial differences in female fertility treatment rates--a new approach to assess differences related to occupation?

AIMS: Infertility is highly prevalent and 16-26% of women trying to achieve a pregnancy experience infertility in one or more periods. Several exposures in the work environment have been hypothesized to affect female reproduction. This study aimed to estimate relative rates (RR) of female fertility treatment in the 57 industrial groups in Denmark. METHODS: The closed cohort of all 20-39 year old economically active women in Denmark by January 2001 (n = 567,816) were followed-up for hospital contacts due to infertility from 2001 to 2005 as registered in the Danish Occupational Hospital Register. Age-standardized relative rates for being diagnosed as infertile were estimated by industry. Further standardization with respect to socioeconomic status was also performed. RESULTS: In total, 12,575 women were diagnosed with infertility during the follow-up period. Three industries presented with statistically significant elevations in age-standardized RRs: hospitals (RR = 1.27, 95% confidence interval (CI): 1.20-1.35), general and dental practice (RR = 1.17, 95% CI: 1.02-1.35) and other health care (RR = 1.24, 95% CI: 1.09-1.41). Standardization for socioeconomic status rendered two industries that were statistically significantly elevated: manufacture of wood and wood products (RR = 1.20, 95% CI: 1.02-1.42) and hospitals (RR = 1.17, 95% CI: 1.10-1.24). CONCLUSIONS: Interpretation of the results is complex, since the relative contributions to the observed inequalities of the work environment and, for example, differences in inclination to start a family or in proneness to seek treatment are difficult to resolve. Withstanding shortcomings and limitations, register data of fertility treatment offers a possibility to suggest industries for further investigation of reproductive health.