Seasonal patterns of sickness absence due to diagnosed mental disorders: a nationwide 12-year register linkage study

AIMS

Although seasonality has been documented for mental disorders, it is unknown whether similar patterns can be observed in employee sickness absence from work due to a wide range of mental disorders with different severity level, and to what extent the rate of change in light exposure plays a role. To address these limitations, we used daily based sickness absence records to examine seasonal patterns in employee sickness absence due to mental disorders.

METHODS

We used nationwide diagnosis-specific psychiatric sickness absence claims data from 2006 to 2017 for adult individuals aged 16-67 (n = 636,543 sickness absence episodes) in Finland, a high-latitude country with a profound variation in daylength. The smoothed time-series of the ratio of observed and expected (O/E) daily counts of episodes were estimated, adjusted for variation in all-cause sickness absence rates during the year.

RESULTS

Unipolar depressive disorders peaked in October-November and dipped in July, with similar associations in all forms of depression. Also, anxiety and non-organic sleep disorders peaked in October-November. Anxiety disorders dipped in January-February and in July-August, while non-organic sleep disorders dipped in April-August. Manic episodes reached a peak from March to July and dipped in September-November and in January-February. Seasonality was not dependent on the severity of the depressive disorder.

CONCLUSIONS

These results suggest a seasonal variation in sickness absence due to common mental disorders and bipolar disorder, with high peaks in depressive, anxiety and sleep disorders towards the end of the year and a peak in manic episodes starting in spring. Rapid changes in light exposure may contribute to sickness absence due to bipolar disorder. The findings can help clinicians and workplaces prepare for seasonal variations in healthcare needs.

Nurse understaffing and short work experience as predictors of healthcare-associated infections

Background

Healthcare-associated infections (HAIs) are a serious risk factor for hospital patients leading to more than 90 000 deaths each year in European countries. It has been evaluated that 7% of patients in European acute care hospitals acquire an HAI, and that a large part of cases could be prevented. Good hand hygiene is central in preventing HAIs, which may be compromised under high work pressure. The aim of this study was to analyse the associations between nurse understaffing and short work experience with the risk of HAIs at patient-level. Prior evidence on this topic remains inconclusive due to a reliance on imprecise measurement of these exposures.

Methods

We utilized administrative data on employees’ working hours and patient records from one hospital district in Finland from years 2013-2019. The data included in total 281,672 inpatient periods. We used mixed-effects survival analyses to predict the overall risk of HAIs, and four types of HAIs: bloodstream, Clostridium difficile, surgical-site and pneumonia. To consider the incubation time, exposure to nurse understaffing and short work experience were measured in preceding days in moving time windows when the patients were in the hospital.

Results

Preliminary results showed that exposure to nurse understaffing within two days, measured as low nursing hours relative to planned hours, was associated with increased risk of HAIs (hazard ratio was 1.23, 95% CI 1.05-1.45). Additional analyses showed that this risk was especially pronounced in surgical-site infections, which were also carefully monitored in the hospital district. We did not find associations between exposure to short work experience among nurses and HAI risk.

Conclusions

This study showed that nurse staffing below planned levels was associated with an increased overall risk of HAIs, particularly surgical-site infections, among patients. Adequate levels of nursing staff in hospitals may be important for preventing HAIs.

Key messages

Hospital nurse understaffing and short work experience: associations with mortality among patients

Background

Determining and maintaining optimal staffing level in hospitals is crucial, as understaffing may have serious consequences and even increase mortality risk among patients. There is no consensus, however, on the optimal way to determine staffing requirements in hospitals as patients’ care needs vary between wards and days. Nurse work experience may also affect quality of care and ultimately patients’ survival but research on this topic is scarce.

Methods

Administrative register data on patients (N = 254,308) and employees of 40 hospital units was used in one hospital district in Finland from years 2013-2019. Both nurse understaffing and nurse work experience were measured with two different indicators in each unit-day. Mixed-effects survival models were used to analyse the associations of these exposures with mortality at patient-level, when adjusted for patients’ characteristics, such as age, sex and comorbidities.

Results

Preliminary results showed that every one percent increase in the cumulative proportion of understaffed days - measured as low nursing hours relative to planned - was associated with 1.002-fold mortality risk among patients (95% CI, 1.000-1.004, p-value=0.044). Short work experience was not associated with increased risk of death.

Conclusions

This study supports previous findings on the associations between nurse understaffing and increased mortality risk among patients in Finland although no association with mortality was found for the other three staffing characteristics. However, the average daily shares of actualized nursing hours relative to planned hours were quite high in hospital units. An indicator based on actualized relative to planned working hours in routine administrative data could be useful in evaluating understaffing in hospitals.

Key messages

• Adequate level of nursing professional in hospitals is related to patient survival.

• It is also crucial of develop efficient ways to evaluate understaffing in hospitals.

Time period effects in work disability due to common mental disorders among young employees

Background

Previous research on period effects in risk for work disability due to common mental disorders across employment sectors and occupational classes in young employees is lacking. Temporal changes in the healthcare system or social insurance policies or other structural/organisational changes could contribute to such time period effects. We aimed to investigate time period effects in the risk of work disability, defined as long-term sickness absence (LTSA) and disability pension (DP) due to common mental disorders (CMDs), among young employees according to their employment sector (private/public) and occupational class (non-manual/manual).

Methods

Three cohorts, including all employed individuals with complete information on employment sector and occupational class, aged 19-29 years and resident in Sweden on the 31-Dec-2004, 2009 and 2014 (n = 573,516, 665,138 and 600,889 individuals in cohort 2004, 2009 and 2014, respectively) were followed for four years. Crude and multivariate-adjusted hazard ratios (HRs and aHRs, respectively) with 95% confidence intervals (CIs) were estimated regarding the risk of LTSA and DP due to CMDs using Cox regression analyses.

Results

In cohort 2004, public sector employees had a higher relative risk for LTSA due to CMDs than private sector employees (aHR, (95%CI): 1.24, 1.16-1.34 and 1.18, 1.11-1.26 among non-manual and manual workers). These associations were similar in the later cohorts. Compared to cohort 2004, the rate of DP due to CMDs was considerably lower in the later cohorts leading to uncertainties in the risk estimates limiting the comparability for time period effects regarding the risk of DP due to CMDs across employment sectors and occupational classes.

Conclusions

Stricter regulation changes regarding the receipt of DP in Sweden, rather than other time period events, may have differentially affected the risk of work disability among young non-manual and manual employees working in the private and public sectors.

Key messages

Social network ties before and after retirement: a cohort study

Social networks are associated with individual's health and well-being. Working life offers opportunities to create and maintain social networks, while retirement may change these networks. This study examined how the number of ties in social network changes across the retirement transition. The study population consisted of 2319 participants (84% women, mean age 63.2 years) from the Finnish Retirement and Aging study. Information about social network ties, including the number of ties in the inner, middle and outer circles of the social convoy model, was gathered using annual postal surveys before and after retirement. Three repeat surveys per participant covered the retirement transition and the post-retirement periods. Mean number of network ties was 21.6 before retirement, of which 5.6 were situated in the inner, 6.9 in the middle and 9.1 in the outer circle. The number of ties in the outer circle decreased by 0.67 (95% CI - 0.92, - 0.42) during the retirement transition period, but not during the post-retirement period (0.11, 95% CI - 0.33, 0.12) (interaction period * time, p = 0.006). The pattern of change in these ties did not differ by gender, occupational status, marital status, number of chronic diseases and mental health during the retirement transition period. The number of ties in the inner and middle circles overall did not decrease during these periods. The number of peripheral relationships decreased during the retirement transition but not after that, suggesting that the observed reduction is more likely to be associated with retirement rather than aging.

Social relationships as predictors of extended employment beyond the pensionable age: a cohort study

The aim is to examine whether characteristics of social relationships predict extended employment beyond the pensionable age among Finnish public sector workers. The study population consisted of 4014 participants (83% women, age 62.56 ± 1.21) of the Finnish Retirement and Aging Study followed between 2014 and 2019. Extended employment was defined as the difference between actual retirement date and individual age-related pensionable date and classified into three groups: no extension (retired on pensionable age or extended by < 3 months), short extension (3 months–< 1 year), and long extension (≥ 1 year) beyond the pensionable date. Characteristics of social relationships and engagement were assessed 18 months prior to the pensionable date. Social engagement was classified into consumptive social participation, formal social participation, informal social participation, and other social participation. Data were analyzed using multinomial regression analysis. Of total study participants, 17.8% belonged to short- and 16.5% belonged to long-extension group. Adjusted for age, occupational status, self-rated health and depression, and having a working spouse (OR 2.34, 95% CI 1.39–3.95) were associated with long extension of employment beyond the pensionable age when compared to no extension among men. Likewise, among women, living alone (OR 1.60, 95% CI 1.28–2.00), having a working spouse (1.85, 1.39–2.45), and high consumptive (1.32, 1.07–1.65), high formal (1.47, 1.17–1.85), and other social participation (0.79, 0.63–0.98) were associated with long extension. Having a working spouse, living alone, and high consumptive social participation were associated with short extension. Several characteristics of social relationships, such as having a working spouse, living alone, and high frequency of social engagement, predicted an extension of employment beyond the pensionable age.

Diabetes and risk of occupational injury: a cohort study

AIMS

To investigate if diabetes is associated with a higher risk of occupational (workplace or commuting) injury.

METHODS

Medication data from the Finnish Prescription Register were used to identify diabetes cases in 2004 in a large employee cohort (the Finnish Public Sector study). These data were linked to injury records obtained from the Federation of Accident Insurance Institutions. A total of 1020 diabetes cases (median age 52 years, range 20 to 65 years; 66% women) and their 5234 age- and sex-matched controls were followed up until 2011. Sex-stratified Cox proportional hazards models, adjusting for age, occupational status, obesity and health behaviours, were applied. Because of the small number of men in the cohort, injury types and locations were only examined among women.

RESULTS

During the median follow-up of 6.7 years, 25% of the participants with diabetes (n=252) and 20% of those without (n=1051) experienced an occupational injury. The association between diabetes and injury was stronger in women than men (P=0.048). Diabetes was associated with a higher risk of workplace (hazard ratio 1.37, 95% CI 1.11 to 1.69) and commuting (hazard ratio 1.36, 95% CI 1.03 to 1.79) injury in women. With regard to different injury types and locations, diabetes was associated with bone fractures, dislocations, sprains and strains, and injuries to upper and lower extremities. In men, there was an association between insulin-treated diabetes and commuting injury (hazard ratio 3.14, 95% CI 1.52 to 6.49).

CONCLUSIONS

Diabetes was associated with workplace and commuting injuries in women. Men with insulin-treated diabetes had a higher risk of commuting injuries.

Job strain as a risk factor for clinical depression: systematic review and meta-analysis with additional individual participant data

BACKGROUND

Adverse psychosocial working environments characterized by job strain (the combination of high demands and low control at work) are associated with an increased risk of depressive symptoms among employees, but evidence on clinically diagnosed depression is scarce. We examined job strain as a risk factor for clinical depression.

METHOD

We identified published cohort studies from a systematic literature search in PubMed and PsycNET and obtained 14 cohort studies with unpublished individual-level data from the Individual-Participant-Data Meta-analysis in Working Populations (IPD-Work) Consortium. Summary estimates of the association were obtained using random-effects models. Individual-level data analyses were based on a pre-published study protocol.

RESULTS

We included six published studies with a total of 27 461 individuals and 914 incident cases of clinical depression. From unpublished datasets we included 120 221 individuals and 982 first episodes of hospital-treated clinical depression. Job strain was associated with an increased risk of clinical depression in both published [relative risk (RR) = 1.77, 95% confidence interval (CI) 1.47-2.13] and unpublished datasets (RR = 1.27, 95% CI 1.04-1.55). Further individual participant analyses showed a similar association across sociodemographic subgroups and after excluding individuals with baseline somatic disease. The association was unchanged when excluding individuals with baseline depressive symptoms (RR = 1.25, 95% CI 0.94-1.65), but attenuated on adjustment for a continuous depressive symptoms score (RR = 1.03, 95% CI 0.81-1.32).

CONCLUSIONS

Job strain may precipitate clinical depression among employees. Future intervention studies should test whether job strain is a modifiable risk factor for depression.

Organizational fairness and psychological distress in hospital physicians

Aims: Prior research has reported high levels of stress for physicians, but determinants of this stress are poorly understood. We explored whether problems in decision-making procedures and treatment of employees, as expressed in the theory of organizational fairness, may contribute to psychological distress in hospital physicians. Methods: Structural equation modelling (LISREL) was based on survey responses from 251 male and 196 female physicians working in 11 public hospitals in Finland. Results: Low organizational fairness increased the risk of psychological distress in male physicians but not in female physicians. In the former group, the association between organizational fairness and psychological distress was partially mediated by decreased job control and increased workload. Conclusions: These findings suggest that broadening the view from the traditional psychosocial work characteristics to justice in management may assist in efforts to promote physicians' health and well-being.

Antidepressant use and work-related injuries

BACKGROUND

Adverse effects of antidepressants are most common at the beginning of the treatment, but possible also later. We examined the association between antidepressant use and work-related injuries taking into account the duration of antidepressant use.

METHOD

Antidepressant use and work-related injuries between 2000 and 2011 were measured among 66 238 employees (mean age 43.8 years, 80% female) using linkage to national records (the Finnish Public Sector study). We analysed data using time-dependent modelling with individuals as their own controls (self-controlled case-series design).

RESULTS

In 2238 individuals who had used antidepressants and had a work-related injury during a mean follow-up of 7.8 years, no increase in the risk of injury was observed in the beginning of antidepressant treatment. However, an increased injury risk was seen after 3 months of treatment (rate ratio, compared with no recent antidepressant use, 1.27, 95% confidence interval 1.10-1.48). This was also the case among those who had used only selective serotonin reuptake inhibitors (n = 714; rate ratio 1.41, 95% confidence interval 1.08-1.83).

CONCLUSIONS

Antidepressant use was not associated with an increased risk of work-related injury at the beginning of treatment. Post-hoc analyses of antidepressant trials are needed to determine whether long-term use of antidepressants increases the risk of work-related injury.

Psychosocial factors associated with work disability in men and women with diabetes: a pooled analysis of three occupational cohort studies

AIMS

To examine the extent to which adverse psychosocial factors, such as living alone, psychological distress, job strain and low support from supervisor, increase the risk of work disability (sickness absence and disability pension) among employees with diabetes.

METHODS

In this pooled analysis of individual-participant data from three occupational cohort studies (the Finnish Public Sector Study, the British Whitehall II study, and the French GAZEL study), 1088 women and 949 men with diabetes were followed up to determine the duration (number of days) and frequency (number of spells) of work disability. The mean follow-up periods were 3.2 years in the GAZEL study, 4.6 years in the Whitehall II study and 4.7 years in the Finnish Public Sector Study. Psychosocial factors and potential confounding factors were assessed at baseline using standard questionnaires. Study-specific estimates were pooled using fixed-effects meta-analysis.

RESULTS

In analysis adjusted for sociodemographic factors, health behaviours and comorbidities, participants with psychological distress had longer (rate ratio 1.66; 95% CI 1.31-2.09) and more frequent absences (rate ratio 1.33; 95% CI 1.19-1.49) compared with those with no psychological distress. Job strain was associated with slightly increased absence frequency (rate ratio 1.19 95% CI 1.05-1.35), but not with absence duration. Living alone and low supervisor support were not associated with absence duration or frequency. We observed no sex differences in these associations.

CONCLUSIONS

Psychological distress was associated with increased duration and frequency of work disability among employees with diabetes. Job strain was associated with increased absence frequency but not with absence duration.

Lifestyle-related risk factors and trajectories of work disability over 5 years in employees with diabetes: findings from two prospective cohort studies

AIMS

To examine work disability trajectories among employees with and without diabetes and identify lifestyle-related factors associated with these trajectories.

METHODS

We assessed work disability using records of sickness absence and disability pension among participants with diabetes and age- sex-, socio-economic status- and marital status-matched controls in the Finnish Public Sector Study (1102 cases; 2204 controls) and the French GAZEL study (500 cases; 1000 controls), followed up for 5 years. Obesity, physical activity, smoking and alcohol consumption were assessed at baseline and the data analysed using group-based trajectory modelling.

RESULTS

Five trajectories described work disability: 'no/very low disability' (41.1% among cases and 48.0% among controls); 'low-steady' (35.4 and 34.7%, respectively); 'high-steady' (13.6 and 12.1%, respectively); and two 'high-increasing' trajectories (10.0 and 5.2%, respectively). Diabetes was associated with a 'high-increasing' trajectory only (odds ratio 1.90, 95% CI 1.47-2.46). Obesity and low physical activity were similarly associated with high work disability in people with and without diabetes. Smoking was associated with 'high-increasing' trajectory in employees with diabetes (odds ratio 1.88, 95% CI 1.21-2.93) but not in those without diabetes (odds ratio 1.32, 95% CI 0.87-2.00). Diabetes was associated with having multiple ( ≥ 2) risk factors (21.1 vs. 11.4%) but the association between multiple risk factors and the 'high-increasing' trajectory was similar in both groups.

CONCLUSIONS

The majority of employees with diabetes have low disability rates, although 10% are on a high and increasing disability trajectory. Lifestyle-related risk factors have similar associations with disability among employees with and without diabetes, except smoking which was only associated with poorer prognosis in diabetes.

Interleukin-6 as a predictor of symptom resolution in psychological distress: a cohort study

BACKGROUND

Elevated levels of interleukin-6 (IL-6) have been associated with the development of common mental disorders, such as depression, but its role in symptom resolution is unclear.

METHOD

We examined the association between IL-6 and symptom resolution in a non-clinical sample of participants with psychological distress.

RESULTS

Relative to high IL-6 levels, low levels at baseline were associated with symptom resolution at follow-up [age- and sex-adjusted risk ratio (RR) = 1.15, 95% confidence interval (CI) 1.06-1.25]. Further adjustment for covariates had little effect on the association. Symptomatic participants with repeated low IL-6 were more likely to be symptom-free at follow-up compared with those with repeated high IL-6 (RR = 1.21, 95% CI 1.03-1.41). Among the symptomatic participants with elevated IL-6 at baseline, IL-6 decreased along with symptom resolution.

CONCLUSIONS

IL-6 is potentially related to the mechanisms underlying recovery from symptoms of mental ill health. Further studies are needed to examine these mechanisms and to confirm the findings in relation to clinical depression.

Job strain and risk of obesity: systematic review and meta-analysis of cohort studies

Job strain, the most widely used indicator of work stress, is a risk factor for obesity-related disorders such as cardiovascular disease and type 2 diabetes. However, the extent to which job strain is related to the development of obesity itself has not been systematically evaluated. We carried out a systematic review (PubMed and Embase until May 2014) and meta-analysis of cohort studies to address this issue. Eight studies that fulfilled inclusion criteria showed no overall association between job strain and the risk of weight gain (pooled odds ratio for job strain compared with no job strain 1.04, 95% confidence interval (CI) 0.99–1.09, N_Total=18 240) or becoming obese (1.00, 95% CI 0.89–1.13, N_Total=42 222). In addition, a reduction in job strain over time was not associated with lower obesity risk (1.13, 95% CI 0.90–1.41, N_Total=6507). These longitudinal findings do not support the hypothesis that job strain is an important risk factor for obesity or a promising target for obesity prevention.

Excess mortality among the elderly in European countries, December 2014 to February 2015

Since December 2014 and up to February 2015, the weekly number of excess deaths from all-causes among individuals?≥?65 years of age in 14 European countries have been significantly higher than in the four previous winter seasons. The rise in unspecified excess mortality coincides with increased proportion of influenza detection in the European influenza surveillance schemes with a main predominance of influenza A(H3N2) viruses seen throughout Europe in the current season, though cold snaps and other respiratory infections may also have had an effect.

A Scandinavian case of skin fragility, alopecia and cardiomyopathy caused by DSP mutations

Congenital skin fragility is a heterogeneous disorder with epidermolysis bullosa and various skin infections as the leading causes. However, even rare diseases must be considered in the differential diagnosis of neonatal skin blistering, including some genetic syndromes with extracutaneous involvement. One such syndrome is ectodermal dysplasia due to deficiency of desmoplakin, a desmosomal protein essential for cellular cohesion in both epithelia and cardiac tissues. Desmoplakin is encoded by the DSP gene, which is localized on chromosome 6p24. Both dominant and recessive mutations in this gene have been reported to cause skin fragility and keratinization defects. We report a child born with a fragile epidermis, alopecia, thick nails, and focal hyperkeratoses on the digits and knees. She was found to have a deficiency of desmoplakin caused by compound heterozygous DSP mutations. She has gradually developed signs of a left ventricular cardiomyopathy.

Job strain and the risk of severe asthma exacerbations: a meta-analysis of individual-participant data from 100 000 European men and women

Background

Many patients and healthcare professionals believe that work‐related psychosocial stress, such as job strain, can make asthma worse, but this is not corroborated by empirical evidence. We investigated the associations between job strain and the incidence of severe asthma exacerbations in working‐age European men and women.

Methods

We analysed individual‐level data, collected between 1985 and 2010, from 102 175 working‐age men and women in 11 prospective European studies. Job strain (a combination of high demands and low control at work) was self‐reported at baseline. Incident severe asthma exacerbations were ascertained from national hospitalization and death registries. Associations between job strain and asthma exacerbations were modelled using Cox regression and the study‐specific findings combined using random‐effects meta‐analyses.

Results

During a median follow‐up of 10 years, 1 109 individuals experienced a severe asthma exacerbation (430 with asthma as the primary diagnostic code). In the age‐ and sex‐adjusted analyses, job strain was associated with an increased risk of severe asthma exacerbations defined using the primary diagnostic code (hazard ratio, HR: 1.27, 95% confidence interval, CI: 1.00, 1.61). This association attenuated towards the null after adjustment for potential confounders (HR: 1.22, 95% CI: 0.96, 1.55). No association was observed in the analyses with asthma defined using any diagnostic code (HR: 1.01, 95% CI: 0.86, 1.19).

Conclusions

Our findings suggest that job strain is probably not an important risk factor for severe asthma exacerbations leading to hospitalization or death.

Job strain in relation to body mass index: pooled analysis of 160 000 adults from 13 cohort studies

BACKGROUND

Evidence of an association between job strain and obesity is inconsistent, mostly limited to small-scale studies, and does not distinguish between categories of underweight or obesity subclasses.

OBJECTIVES

To examine the association between job strain and body mass index (BMI) in a large adult population.

METHODS

We performed a pooled cross-sectional analysis based on individual-level data from 13 European studies resulting in a total of 161 746 participants (49% men, mean age, 43.7 years). Longitudinal analysis with a median follow-up of 4 years was possible for four cohort studies (n = 42 222).

RESULTS

A total of 86 429 participants were of normal weight (BMI 18.5-24.9 kg m(-2) ), 2149 were underweight (BMI < 18.5 kg m(-2) ), 56 572 overweight (BMI 25.0-29.9 kg m(-2) ) and 13 523 class I (BMI 30-34.9 kg m(-2) ) and 3073 classes II/III (BMI ≥ 35 kg m(-2) ) obese. In addition, 27 010 (17%) participants reported job strain. In cross-sectional analyses, we found increased odds of job strain amongst underweight [odds ratio 1.12, 95% confidence interval (CI) 1.00-1.25], obese class I (odds ratio 1.07, 95% CI 1.02-1.12) and obese classes II/III participants (odds ratio 1.14, 95% CI 1.01-1.28) as compared with participants of normal weight. In longitudinal analysis, both weight gain and weight loss were related to the onset of job strain during follow-up.

CONCLUSIONS

In an analysis of European data, we found both weight gain and weight loss to be associated with the onset of job strain, consistent with a 'U'-shaped cross-sectional association between job strain and BMI. These associations were relatively modest; therefore, it is unlikely that intervention to reduce job strain would be effective in combating obesity at a population level.

Long working hours and symptoms of anxiety and depression: a 5-year follow-up of the Whitehall II study

BACKGROUND

Although long working hours are common in working populations, little is known about the effect of long working hours on mental health.

METHOD

We examined the association between long working hours and the onset of depressive and anxiety symptoms in middle-aged employees. Participants were 2960 full-time employees aged 44 to 66 years (2248 men, 712 women) from the prospective Whitehall II cohort study of British civil servants. Working hours, anxiety and depressive symptoms, and covariates were measured at baseline (1997-1999) followed by two subsequent measurements of depressive and anxiety symptoms (2001 and 2002-2004).

RESULTS

In a prospective analysis of participants with no depressive (n=2549) or anxiety symptoms (n=2618) at baseline, Cox proportional hazard analysis adjusted for baseline covariates showed a 1.66-fold [95% confidence interval (CI) 1.06-2.61] risk of depressive symptoms and a 1.74-fold (95% CI 1.15-2.61) risk of anxiety symptoms among employees working more than 55 h/week compared with employees working 35-40 h/week. Sex-stratified analysis showed an excess risk of depression and anxiety associated with long working hours among women [hazard ratios (HRs) 2.67 (95% CI 1.07-6.68) and 2.84 (95% CI 1.27-6.34) respectively] but not men [1.30 (0.77-2.19) and 1.43 (0.89-2.30)].

CONCLUSIONS

Working long hours is a risk factor for the development of depressive and anxiety symptoms in women.

Sickness absence among Finnish special and general education teachers

BACKGROUND

Although teaching is considered a high-stress profession, research on stress-related outcomes among teachers, such as absence from work due to illness (i.e. sickness absence), remains scarce. It is possible that teachers are not a homogeneous group but include subgroups with particularly high risk of sickness absence, such as special education teachers.

AIMS

To examine differences in sickness absence rates between special and general education teachers in a large cohort of 2291 Finnish lower secondary school teachers.

METHODS

Register data on teachers' job titles, sociodemographic characteristics and sickness absence were obtained from 10 municipal employers' registers. Indices of sickness absence included rates of short-term (1-3 days) and long-term (>3 days) absence spells during 2003-05.

RESULTS

With multi-level models adjusted for individual- and school-level covariates, we found that although the absolute level of sickness absence was higher among women than among men, male special education teachers were at a 1.36-fold (95% CI: 1.15-1.61) increased risk of short-term and a 1.33-fold (95% CI: 1.01-1.76) increased risk of long-term sickness absence compared with male teachers in general education. Among women, there were no differences in sickness absence between special and general education teachers.

CONCLUSIONS

Compared to male teachers in general education, male teachers in special education appear to have an excess risk of absence from work due to illness. Future studies should examine the causes for this excess risk and determine the need for preventive interventions.

Immortalized keratinocytes derived from patients with epidermolytic ichthyosis reproduce the disease phenotype: a useful in vitro model for testing new treatments

BACKGROUND

Epidermolytic ichthyosis (EI) is a skin fragility disorder caused by mutations in genes encoding suprabasal keratins 1 and 10. While the aetiology of EI is known, model systems are needed for pathophysiological studies and development of novel therapies.

OBJECTIVES

To generate immortalized keratinocyte lines from patients with EI for studies of EI cell pathology and the effects of chemical chaperones as putative therapies.

METHODS

We derived keratinocytes from three patients with EI and one healthy control and established immortalized keratinocytes using human papillomavirus 16-E6/E7. Growth and differentiation characteristics, ability to regenerate organotypic epidermis, keratin expression, formation of cytoskeletal aggregates, and responses to heat shock and chemical chaperones were assessed.

RESULTS

The cell lines EH11 (K1_p.Val176_Lys197del), EH21 (K10_p.156Arg>Gly), EH31 (K10_p.Leu161_Asp162del) and NKc21 (wild-type) currently exceed 160 population doublings and differentiate when exposed to calcium. At resting state, keratin aggregates were detected in 9% of calcium-differentiated EH31 cells, but not in any other cell line. Heat stress further increased this proportion to 30% and also induced aggregates in 3% of EH11 cultures. Treatment with trimethylamine N-oxide and 4-phenylbutyrate (4-PBA) reduced the fraction of aggregate-containing cells and affected the mRNA expression of keratins 1 and 10 while 4-PBA also modified heat shock protein 70 (HSP70) expression. Furthermore, in situ proximity ligation assay suggested a colocalization between HSP70 and keratins 1 and 10. Reconstituted epidermis from EI cells cornified but EH21 and EH31 cells produced suprabasal cytolysis, closely resembling the in vivo phenotype.

CONCLUSIONS

These immortalized cell lines represent a useful model for studying EI biology and novel therapies.

Preoperative levosimendan infusion in combined aortic valve and coronary bypass surgery

BACKGROUND

Cardiopulmonary bypass may have detrimental effects on intestinal function and decrease the concentrations of the active, long-acting metabolites of levosimendan, an inodilator used to improve cardiac function. The aim of this study was to evaluate the haemodynamic effects of preoperative levosimendan in patients undergoing high-risk cardiac surgery.

METHODS

Twenty-four patients were randomized to receive levosimendan (12 µg bolus followed by an infusion of 0.2 µg kg(-1) min(-1)) or a placebo 24 h before surgery. The inclusion criteria were left ventricular ejection fraction (LVEF) <50% or LV hypertrophy indicated by a wall thickness of >12 mm. Haemodynamics were recorded every hour for 24 h (pulmonary artery catheter) and daily until postoperative day 4 (whole-body impedance cardiography). Doppler echocardiography with tissue Doppler imaging was used to assess systolic and diastolic cardiac function.

RESULTS

The cardiac index (CI) and stroke volume index (SI) were higher in the levosimendan group (LG) for the 4 day postoperative period (P<0.05); on the fourth postoperative day, the CI was 3.0 litre m(-2) min(-1) in the LG compared with 2.4 litre m(-2) min(-1) in the control group (CG) and the SI was 30 vs 25 ml m(-2), respectively. The LVEF measured at baseline and on the fourth postoperative morning decreased in the CG, but was maintained in the LG.

CONCLUSIONS

Levosimendan improved haemodynamics compared with a placebo in patients undergoing high-risk cardiac surgery. The concentrations of levosimendan's metabolites were higher compared with earlier studies using perioperative dosing.

Early retirement from work among employees with a diagnosis of personality disorder compared to anxiety and depressive disorders

OBJECTIVE

Risk of retirement from work before statutory retirement age among employees with personality disorders is unknown.

METHOD

We used diagnoses of awarded medical rehabilitations and hospitalisations to select two clinical cohorts from a population of 151,618 employees: participants in rehabilitation (total N=1942, 233 personality disorder, 419 anxiety disorder and 1290 depression cases) and hospitalised patients (N=1333, 354, 126 and 853, respectively). Early retirement from work was tracked through national registers during a period of 5 years. Cox proportional hazard models were used to examine the association of diagnostic groups with risk of early retirement.

RESULTS

In models adjusted for age, sex and socioeconomic position, the relative risk of early retirement for patients with personality disorders was 3.5-fold (95% CI 2.1 to 5.8) in the rehabilitation cohort and 2.3-fold (95% CI 1.6 to 3.5) in the hospital cohort compared with anxiety disorders. The corresponding hazard ratios of early retirement for personality disorders compared with depressive disorders were 1.1 (95% CI 0.8-1.5) and 1.7 (95% CI 1.4-2.1), respectively.

CONCLUSIONS

Personality disorders increase the risk of early retirement at least to an equal extent as depression and more than twice that of anxiety disorders.

Work disability following major organisational change: the Whitehall II study

BACKGROUND

Privatisation and private sector practices have been increasingly applied to the public sector in many industrialised countries. Over the same period, long-term work disability has risen substantially. We examined whether a major organisational change--the transfer of public sector work to executive agencies run on private sector lines--was associated with an increased risk of work disability.

METHODS

The study uses self-reported data from the prospective Whitehall II cohort study. Associations between transfer to an executive agency assessed at baseline (1991-1994) and work disability ascertained over a period of approximately 8 years at three follow-up surveys (1995-1996, 1997-1999 and 2001) were examined using Cox proportional hazard models.

RESULTS

In age- and sex-adjusted models, risk of work disability was higher among the 1263 employees who were transferred to an executive agency (HR 1.90, 95% CI 1.46 to 2.48) compared with the 3419 employees whose job was not transferred. These findings were robust to additional adjustment for physical and mental health and health behaviours at baseline.

CONCLUSIONS

Increased work disability was observed among employees exposed to the transfer of public sector work to executive agencies run on private sector lines. This may highlight an unintentional cost for employees, employers and society.

Physical and cognitive function in midlife: reciprocal effects? A 5-year follow-up of the Whitehall II study

BACKGROUND

Cognitive and physical functions are closely linked in old age, but less is known about this association in midlife. Whether cognitive function predicts physical function and whether physical function predicts cognitive function were assessed in middle-aged men and women.

METHODS

Data were from Whitehall II, an ongoing large-scale, prospective occupational cohort study of employees from 20 London-based white-collar Civil Service departments. The participants, 3446 men and 1274 women aged 45-68 years at baseline (1995-1997), had complete data on cognitive performance and physical function at both baseline and follow-up (2002-2004). A composite cognitive score was compiled from the following tests: verbal memory, inductive reasoning (Alice Heim 4-I), verbal meaning (Mill Hill), phonemic and semantic fluency. Physical function was measured using the physical composite score of the short form (SF-36) scale. Average follow-up was 5.4 years.

RESULTS

Poor baseline cognitive performance predicted poor physical function at follow-up (beta = 0.08, p<0.001), while baseline physical function did not predict cognitive performance (beta = 0.01, p = 0.67). After full adjustment for sociodemographic, behavioural and biological risk factors, baseline cognitive performance (beta = 0.04 p = 0.009) remained predictive of physical function.

CONCLUSION

Despite previous work indicating that the association between physical and cognitive performance may be bidirectional, these findings suggest that, in middle age, the direction of the association is predominantly from poor cognition to poor physical function.