T. Theorell

Bio: T. Theorell is an academic researcher from Stockholm University. The author has contributed to research in topics: Job strain & Job control. The author has an hindex of 7, co-authored 8 publications receiving 504 citations.

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

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published cohort studies from a systematic literature search in PubMed and PsycNET and obtained 14 cohort studies with unpublished individual-level data from the Individual-Participant-Data Meta-analysis in Working Populations (IPD-Work) Consortium.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 From unpublished datasets we included 120 221 individuals and 982 first episodes of hospital-treated clinical depression.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risk of clinical depression in both published [relative risk (RR) = 1.77, 95% confidence interval (CI) 1.47-2.13] and unpublished datasets (RR = 1.27, 95% CI 1.04-1.55).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

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

Abstract: 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.

Job strain and the risk of stroke : an individual-participant data meta-analysis

Abstract: BACKGROUND AND PURPOSE: Psychosocial stress at work has been proposed to be a risk factor for cardiovascular disease However, its role as a risk factor for stroke is uncertain METHODS: We conducted an individual-participant-data meta-analysis of 196 380 males and females from 14 European cohort studies to investigate the association between job strain, a measure of work-related stress, and incident stroke RESULTS: In 18 million person-years at risk (mean follow-up 92 years), 2023 first-time stroke events were recorded The age- and sex-adjusted hazard ratio for job strain relative to no job strain was 124 (95% confidence interval, 105;147) for ischemic stroke, 101 (95% confidence interval, 075;136) for hemorrhagic stroke, and 109 (95% confidence interval, 094;126) for overall stroke The association with ischemic stroke was robust to further adjustment for socioeconomic status CONCLUSION: Job strain may be associated with an increased risk of ischemic stroke, but further research is needed to determine whether interventions targeting job strain would reduce stroke risk beyond existing preventive strategies

Job insecurity and risk of diabetes: a meta-analysis of individual participant data

Abstract: BACKGROUND: Job insecurity has been associated with certain health outcomes. We examined the role of job insecurity as a risk factor for incident diabetes.METHODS: We used individual participant da ...

Job insecurity and risk of diabetes: a meta-analysis of individual participant data

Abstract: BACKGROUND: Job insecurity has been associated with certain health outcomes. We examined the role of job insecurity as a risk factor for incident diabetes.METHODS: We used individual participant da ...

Loneliness and social isolation as risk factors for coronary heart disease and stroke: systematic review and meta-analysis of longitudinal observational studies

Abstract: Background The influence of social relationships on morbidity is widely accepted, but the size of the risk to cardiovascular health is unclear. Objective We undertook a systematic review and meta-analysis to investigate the association between loneliness or social isolation and incident coronary heart disease (CHD) and stroke. Methods Sixteen electronic databases were systematically searched for longitudinal studies set in high-income countries and published up until May 2015. Two independent reviewers screened studies for inclusion and extracted data. We assessed quality using a component approach and pooled data for analysis using random effects models. Results Of the 35 925 records retrieved, 23 papers met inclusion criteria for the narrative review. They reported data from 16 longitudinal datasets, for a total of 4628 CHD and 3002 stroke events recorded over follow-up periods ranging from 3 to 21 years. Reports of 11 CHD studies and 8 stroke studies provided data suitable for meta-analysis. Poor social relationships were associated with a 29% increase in risk of incident CHD (pooled relative risk: 1.29, 95% CI 1.04 to 1.59) and a 32% increase in risk of stroke (pooled relative risk: 1.32, 95% CI 1.04 to 1.68). Subgroup analyses did not identify any differences by gender. Conclusions Our findings suggest that deficiencies in social relationships are associated with an increased risk of developing CHD and stroke. Future studies are needed to investigate whether interventions targeting loneliness and social isolation can help to prevent two of the leading causes of death and disability in high-income countries. Study registration number CRD42014010225.

Stress and cardiovascular disease

Abstract: The physiological reaction to psychological stress, involving the hypothalamic-pituitary-adrenocortical and sympatho-adrenomedullary axes, is well characterized, but its link to cardiovascular disease risk is not well understood. Epidemiological data show that chronic stress predicts the occurrence of coronary heart disease (CHD). Employees who experience work-related stress and individuals who are socially isolated or lonely have an increased risk of a first CHD event. In addition, short-term emotional stress can act as a trigger of cardiac events among individuals with advanced atherosclerosis. A stress-specific coronary syndrome, known as transient left ventricular apical ballooning cardiomyopathy or stress (Takotsubo) cardiomyopathy, also exists. Among patients with CHD, acute psychological stress has been shown to induce transient myocardial ischemia and long-term stress can increase the risk of recurrent CHD events and mortality. Applications of the 'stress concept' (the understanding of stress as a risk factor and the use of stress management) in the clinical settings have been relatively limited, although the importance of stress management is highlighted in European guidelines for cardiovascular disease prevention.

Stress and Cardiovascular Disease: An Update on Current Knowledge

Abstract: Considerable progress has been made during the past decade in research on cardiovascular effects of stress. Early-life stressors, such as childhood abuse and early socioeconomic adversity, are linked to increased cardiovascular morbidity in adulthood. Our updated meta-analyses of prospective studies published until 2011 show a 1.5-fold (95% confidence interval 1.2–1.9) increased risk of coronary heart disease among adults experiencing social isolation and a 1.3-fold (1.2–1.5) excess risk for workplace stress; adverse metabolic changes are one of the underlying plausible mechanisms. Stress, anger, and depressed mood can act as acute triggers of major cardiac events; the pooled relative risk of acute coronary syndrome onset being preceded by stress is 2.5 (1.8–3.5) in case-crossover studies. Stress is also implicated in the prognosis of cardiovascular disease and in the development of stress (takotsubo) cardiomyopathy. A major challenge over the next decade is to incorporate stress processes into the mainst...

Effects of stress on the development and progression of cardiovascular disease

Abstract: Cardiovascular disease remains the leading cause of disease burden globally, which underlies the continuing need to identify new complementary targets for prevention. Over the past 5-10 years, the pooling of multiple data sets into 'mega-studies' has accelerated progress in research on stress as a risk and prognostic factor for cardiovascular disease. Severe stressful experiences in childhood, such as physical abuse and household substance abuse, can damage health and increase the risk of multiple chronic conditions in adulthood. Compared with childhood stress and adulthood classic risk factors, such as smoking, high blood pressure, and high serum cholesterol levels, the harmful effects of stress in adulthood are generally less marked. However, adulthood stress has an important role as a disease trigger in individuals who already have a high atherosclerotic plaque burden, and as a determinant of prognosis and outcome in those with pre-existing cardiovascular or cerebrovascular disease. In real-life settings, mechanistic studies have corroborated earlier laboratory-based observations on stress-related pathophysiological changes that underlie triggering, such as lowered arrhythmic threshold and increased sympathetic activation with related increases in blood pressure, as well as pro-inflammatory and procoagulant responses. In some clinical guidelines, stress is already acknowledged as a target for prevention for people at high overall risk of cardiovascular disease or with established cardiovascular disease. However, few scalable, evidence-based interventions are currently available.