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published cohort studies from a systematic literature search in PubMed and PsycNET and obtained 14 cohort studies with unpublished individual-level data from the Individual-Participant-Data Meta-analysis in Working Populations (IPD-Work) Consortium.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 From unpublished datasets we included 120 221 individuals and 982 first episodes of hospital-treated clinical depression.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risk of clinical depression in both published [relative risk (RR) = 1.77, 95% confidence interval (CI) 1.47-2.13] and unpublished datasets (RR = 1.27, 95% CI 1.04-1.55).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.

Impact of rheumatic diseases on oral health and quality of life.

OBJECTIVE: We investigated the effects of rheumatic diseases on oral symptoms, health habits, and quality of life in subjects with and without rheumatic diseases. The hypothesis was that patients with rheumatic diseases have more oral symptoms impairing their quality of life than healthy controls. METHODS: A questionnaire was mailed to a random sample of 1500 members of the Finnish Rheumatism Association, including those with and without rheumatic diseases. We focused on symptoms of the mouth and temporomandibular area, and health habits. Oral Health Impact Profile (OHIP14) was used to evaluate the oral health-related quality of life. We analyzed differences between subjects with and without rheumatic diseases, controlled for age, gender, smoking, and non-rheumatic chronic diseases. RESULTS: Completed questionnaires were received from 995 participants (response rate 66%). Of them, 564 reported rheumatic disease, 431 were used as controls. The patients reported significantly more all orofacial symptoms than controls. Severe dry mouth was reported by 19.6% of patients and 2.9% of controls (P < 0.001), and temporomandibular joint symptoms by 59.2% and 27.2% (P < 0.001), respectively. In the OHIP-14 questionnaire, the mean total score was significantly higher in patients (8.80 ± 11.15) than in controls (3.93 ± 6.60; P < 0.001). CONCLUSION: The study hypothesis was confirmed by showing that the patients with rheumatic diseases reported oral discomfort and reduced quality of life more often when compared with controls.

Blood parasites mediate morph-specific maintenance costs in a colour polymorphic wild bird.

Parasites can mediate profound negative effects on host fitness. Colour polymorphism has been suggested to covary genetically with intrinsic physiological properties. Tawny owl colour polymorphism is highly heritable with two main morphs, grey and brown. We show that experimental medication acts to reduce blood parasites and that medicated grey females maintain body mass during breeding, whereas medicated brown females decline in body mass similar to control females of both morphs. We find no effect of medication on general immunoglobulin levels, antigen-specific humoral response or H/L ratio. In the descriptive data, both morphs have similar blood parasite infection rates, but blood parasite infection is associated with decreased body mass in brown but not in grey females. We conclude that blood parasite infection primarily has somatic costs, which differ between the two highly heritable tawny owl colour morphs with more pronounced costs in the grey (little pigmented) morph than in the brown (heavily pigmented) morph. Because our descriptive results imply the opposite pattern, our findings highlight the need of experimental manipulation when studying heritable variation in hosts' response to parasitism.

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.

The association between team climate at work and mental health in the Finnish Health 2000 Study.

OBJECTIVES: Depression, anxiety and alcohol use disorders are common mental health problems in the working population. However, the team climate at work related to these disorders has not been studied using standardised interview methods and it is not known whether poor team climate predicts antidepressant use. This study investigated whether team climate at work was associated with DSM-IV depressive, anxiety and alcohol use disorders and subsequent antidepressant medication in a random sample of Finnish employees. METHODS: The nationally representative sample comprised 3347 employees aged 30-64 years. Team climate was measured with a self-assessment scale. Diagnoses of depressive, anxiety and alcohol use disorders were based on the Composite International Diagnostic Interview. Data on the purchase of antidepressant medication in a 3-year follow-up period were collected from a nationwide pharmaceutical register of the Social Insurance Institution. RESULTS: In the risk factor adjusted models, poor team climate at work was significantly associated with depressive disorders (OR 1.61, 95% CI 1.10 to 2.36) but not with alcohol use disorders. The significance of the association between team climate and anxiety disorders disappeared when the model was adjusted for job control and job demands. Poor team climate also predicted antidepressant medication (OR 1.53, 95% CI 1.02 to 2.30). CONCLUSION: A poor team climate at work is associated with depressive disorders and subsequent antidepressant use.

Occupational burnout and chronic work disability: an eight-year cohort study on pensioning among Finnish forest industry workers.

BACKGROUND: The objective was to explore if burnout, a syndrome from chronic work stress, predicts work disability during eight years among industrial employees. We investigated whether burnout would predict disability in initially healthy employees and all subgroups by the most common causes for disability. METHODS: Of the participants in a company-wide survey (n=9705, 63%) performed in 1996, 8371 employees were identified and 7810 provided full information. The impact of burnout and its sub-dimensions, assessed with the Maslach Burnout Inventory-General Survey, on being granted register-based new disability pension till 2004 was analysed with Cox hazard regression and multinomial regression. The analyses were adjusted for socio-demographic factors, registered medication use, and self-reported chronic illness at baseline. RESULTS: The hazard ratio (HR) for new disability pension was 3.8 (95% confidence interval CI 2.7-5.4) with severe burnout. The risk of severe burnout and severe exhaustion for work disability attenuated but remained significant after adjustments. The association between severe burnout and work disability was significant also in the subpopulation of employees without registered medication at baseline but not among employees healthy by self-report. Crude associations between burnout and all categories of cause-specific disability were significant. The exhaustion dimension predicted work disability due to mental and miscellaneous disorders after adjustments. LIMITATIONS: A non-random one-branch sample was used. The final sample covered 50% of eligible employees. CONCLUSIONS: In industrial work, burnout-related chronic work disability is general in nature. Burnout predicts work disability among healthy employees when health is assessed with registered use of medication but not when it is determined by self-report.

Occupational burnout as a predictor of disability pension: a population-based cohort study.

OBJECTIVES: The aim of this study was to investigate whether burnout predicts new disability pension at population level during a follow-up of approximately 4 years. The diagnosis for which the disability pension was granted was also examined in relation to the level of burnout. METHODS: We used a population-based cohort sample (n = 3125) of 30-60-year-old employees from an epidemiological health study, the Health 2000 Study, gathered during 2000-2001 in Finland. The data collection comprised an interview, a clinical health examination including a standardised mental health interview, and a questionnaire including the Maslach Burnout Inventory-General Survey. Disability pensions and their causes until December 2004 were extracted from national pension records. The association between burnout and new disability pension was analysed with logistic regression models adjusted for sociodemographic factors and health at baseline. RESULTS: Altogether 113 persons were granted a new disability pension during the follow-up: 22% of those with severe burnout, 6% of those with mild burnout, and 2% of those with no burnout at baseline. After sociodemographic factors and health were adjusted for, each one-point increase in the overall burnout sum score was related to 49% increase in the odds for a future disability pension. A disability pension was most often granted on the basis of mental and behavioural disorders and diseases of the musculoskeletal system among those with burnout. After adjustments, exhaustion dimension among men and cynicism dimension among a combined group of men and women predicted new disability pensions. CONCLUSION: Burnout predicts permanent work disability and could therefore be used as a risk marker of chronic health-related work stress. To prevent early exit from work life, working conditions and employee burnout should be regularly assessed with the help of occupational health services.

Contribution of non-work and work-related risk factors to the association between income and mental disorders in a working population: the Health 2000 Study.

OBJECTIVES: To examine the contribution of non-work and work factors to the association between income and DSM-IV depressive and anxiety disorders in a working population. METHODS: A representative sample of the Finnish working population aged 30-64 (1667 men, 1707 women) in 2000-2001 responded to a survey questionnaire on non-work factors (marital status, housing conditions, non-work social support, violence victimisation, smoking, physical symptoms), work factors (job demands, job control, social support at work, educational prospects, job insecurity) and household income. Somatic health was examined in a standard health examination. The 12-month prevalence of depressive and anxiety disorders was examined with the Composite International Diagnostic Interview. RESULTS: The risk of having a depressive or anxiety disorder was 2.8 times higher in the low-income group than in the high-income group among men and 2.0 times higher among women. For men, non-work and work factors explained 20% and 31% of this association, respectively. For women, the corresponding figures were 65% and 23%. CONCLUSIONS: Low income is associated with frequent mental disorders among a working population. In particular, work factors among men and non-work factors among women contribute to the income differences in mental health.

Frontal tests do not detect frontal infarctions after ruptured intracranial aneurysm.

The series of 155 patients operated on for a ruptured intracranial arterial aneurysm was examined using typical frontal tests (the Stroop test, word fluency tasks, and a sorting task), as well as a learning and memory test. Patients with frontal infarction were not significantly inferior to patients with non-frontal infarction or to patients with no infarction. Frontal patients, however, were unable to return to work as often as non-frontal patients and more frequently than those with no infarction. These results indicate that the frontal tests used in this study are not selectively sensitive to mainly medial frontal infarctions that follow the rupture of an anterior cerebral artery aneurysm.

Prediction of psychosocial recovery after head injury with cognitive tests and neurobehavioral ratings.

A series of 53 patients was studied using a battery of tests and a neurobehavioral rating scale on average 4 months after closed-head injury (CHI). Social outcome was assessed 1 year after injury by interviewing a family member. The results supported the hypothesis that tests of flexibility and programming rather than tests of cognitive skills predict psychosocial recovery after CHI. Spatial Learning with Self-Set Goals and Sorting were measures of flexibility and programming. Contrary to expectation, word fluency performance was unrelated to these measures, but was associated with conventional intelligence tests, which did not predict psychosocial recovery. Cognition/Energy deficit on the Neurobehavioral Rating Scale and increased age were useful predictors of poor psychosocial outcome, whereas computed tomography findings or the Glasgow Coma Score were weakly related to the outcome indices. Evidently, cognitive flexibility and mental programming are very important psychological prerequisites of social recovery after CHI.

Diminished arterial elasticity in diabetes: association with fluorescent advanced glycosylation end products in collagen.

OBJECTIVE: Non-enzymatic glycosylation of proteins occurs in diabetes and advanced glycosylated end products can accumulate in long lived proteins such as vascular collagen and reduce the elasticity of vessel walls. To evaluate the potential association of advanced glycosylated end products in collagen with diminished arterial elasticity in diabetes, 14 diabetic and 14 age and sex matched non-diabetic patients with coronary artery disease were studied. METHODS: Arterial elasticity was assessed in terms of carotid to femoral pulse wave velocity and by measuring the change in ascending aortic diameter induced by pulse pressure. Collagen linked fluorescence, a measure of advanced glycosylated end products, was determined from tissue specimens of the skin, ascending aorta, and right atrial appendage taken during coronary bypass surgery. RESULTS: As a sign of diminished arterial elasticity, carotid to femoral pulse wave velocity was raised (p < 0.01) and change in ascending aortic diameter tended to be diminished (p = 0.09) in the diabetic patients. Collagen linked fluorescence was increased (p < 0.05) in the myocardium of the diabetic group, but the difference in skin and aorta was not significant. Collagen linked fluorescence between the aorta, skin, and myocardium correlated with each other (r = 0.64-0.77). Collagen linked fluorescence in the aorta and myocardium correlated with carotid to femoral pulse wave velocity (r = 0.63 and r = 0.67, respectively) in the diabetic group but not in the control group. CONCLUSIONS: These data suggest that non-enzymatic glycosylation of matrix proteins, and specifically collagen, may modify arterial elasticity in diabetic patients with coronary artery disease.