Job strain in the public sector and hospital in-patient care use in old age: a 28-year prospective follow-up

Synergistic Effects of Chronic Restraint-Induced Stress and Low-Dose 56Fe-particle Irradiation on Induction of Chromosomal Aberrations in Trp53-Heterozygous Mice

Astronauts can develop psychological stress (PS) during space flights due to the enclosed environment, microgravity, altered light-dark cycles, and risks of equipment failure or fatal mishaps. At the same time, they are exposed to cosmic rays including high atomic number and energy (HZE) particles such as iron-56 (Fe) ions. Psychological stress or radiation exposure can cause detrimental effects in humans. An earlier published pioneering study showed that chronic restraint-induced psychological stress (CRIPS) could attenuate Trp53 functions and increase carcinogenesis induced by low-linear energy transfer (LET) γ rays in Trp53-heterozygous (Trp53+/-) mice. To elucidate possible modification effects from CRIPS on high-LET HZE particle-induced health consequences, Trp53+/- mice were received both CRIPS and accelerated Fe ion irradiation. Six-week-old Trp53+/- C57BL/6N male mice were restrained 6 h per day for 28 consecutive days. On day 8, they received total-body Fe-particle irradiation (Fe-TBI, 0.1 or 2 Gy). Metaphase chromosome spreads prepared from splenocytes at the end of the 28-day restraint regimen were painted with the fluorescence in situ hybridization (FISH) probes for chromosomes 1 (green), 2 (red) and 3 (yellow). Induction of psychological stress in our experimental model was confirmed by increase in urinary corticosterone level on day 7 of restraint regimen. Regardless of Fe-TBI, CRIPS reduced splenocyte number per spleen at the end of the 28-day restraint regimen. At 2 Gy, Fe-TBI alone induced many aberrant chromosomes and no modifying effect was detected from CRIPS on induction of aberrant chromosomes. Notably, neither Fe-TBI at 0.1 Gy nor CRIPS alone induced any increase in the frequency of aberrant chromosomes, while simultaneous exposure resulted in a significant increase in the frequency of chromosomal exchanges. These findings clearly showed that CRIPS could enhance the frequency of chromosomal exchanges induced by Fe-TBI at a low dose of 0.1 Gy.

Retirement age and type as predictors of frailty: a retrospective cohort study of older businessmen

OBJECTIVES

To study the association between retirement characteristics and frailty in a homogenous population of former business executives.

DESIGN

Cross-sectional cohort study using data from the Helsinki Businessmen Study.

SETTING

Helsinki, Finland.

PARTICIPANTS

1324 Caucasian men, born in 1919-1934, who had worked as business executives and managers and of whom 95.9% had retired by the year 2000. Questions on age at and type of retirement, lifestyle and chronic conditions were embedded in questionnaires.

PRIMARY AND SECONDARY OUTCOME MEASURES

Frailty assessed according to a modified phenotype definition at mean age 73.3 years.

RESULTS

Mean age at retirement was 61.3 years (SD 4.3) and 37.1% had retired due to old age. The prevalence of frailty was lowest among men retiring at ages 66-67 years but increased among those who worked up to age 70 years or older. Compared with men who retired before age 55 years, those retiring at ages 58-69 years were at decreased risk of frailty in old age relative to non-frailty (adjusted ORs 0.07-0.29, p<0.05). Compared with men who transitioned into old age retirement, those who retired due to disability were at increased risk of prefrailty (adjusted OR 1.53, 95% CI 1.01 to 2.32) and frailty (adjusted OR 3.52, 95% CI 1.97 to 6.29), relative to non-frailty.

CONCLUSION

Exiting working life early and continuing to be occupationally active until age 70 years and older were both associated with increased risk of frailty among the men. Promotion of longer work careers could, however, promote healthier ageing, as the lowest prevalence of frailty was observed in former business executives who retired at ages 66-67 years.

[The medical community's perceptions of management of the layoff process]

The definition and process of layoff are evolving rapidly. This study focuses on the perceptions of physicians in Catalonia, Spain, concerning layoff and the identification of strategies and proposals that allow more satisfactory adjustment to the process. A qualitative approach was used with 16 in-depth interviews with key persons in the healthcare setting (phase 1) and 6 focus groups with 72 persons, according to sampling criteria (phase 2). The analysis was interpretative, based on Grounded Theory. Comparison and triangulation of the results generated by the different techniques and researchers revealed the social representation of the current healthcare organization (immersed in a new public management model) on the medical community and the layoff process. In this sense, retirement is seen as a personal issue, separate from human resources policies, which are more interested in staff turnover at a lower "cost". Given this situation, the article proposes alternatives that value physicians' experience and expertise before they leave the healthcare organization.

Effects of chronic restraint-induced stress on radiation-induced chromosomal aberrations in mouse splenocytes

Both ionizing radiation (IR) and psychological stress (PS) cause detrimental effects on humans. A recent study showed that chronic restraint-induced PS (CRIPS) diminished the functions of Trp53 and enhanced radiocarcinogenesis in Trp53-heterozygous (Trp53^+/-) mice. These findings had a marked impact on the academic field as well as the general public, particularly among residents living in areas radioactively contaminated by nuclear accidents. In an attempt to elucidate the modifying effects of CRIPS on radiation-induced health consequences in Trp53 wild-type (Trp53^+/+) animals, investigations involving multidisciplinary analyses were performed. We herein demonstrated that CRIPS induced changes in the frequency of IR-induced chromosomal aberrations (CAs) in splenocytes. Five-week-old male Trp53^+/+ C57BL/6J mice were restrained for 6h per day for 28 consecutive days, and total body irradiation (TBI) at a dose of 4Gy was performed on the 8th day. Metaphase chromosome spreads prepared from splenocytes at the end of the 28-day restraint regimen were painted with fluorescence in situ hybridization (FISH) probes for chromosomes 1, 2, and 3. The results obtained showed that CRIPS alone did not induce CAs, while TBI caused significant increases in CAs, mostly translocations. Translocations appeared at a lower frequency in mice exposed to TBI plus CRIPS than in those exposed to TBI alone. No significant differences were observed in the frequencies of the other types of CAs (insertions, dicentrics, and fragments) visualized with FISH between these experimental groups (TBI+CRIPS vs. TBI). These results suggest that CRIPS does not appear to synergize with the clastogenicity of IR.

Physical occupational exposures and health expectancies in a French occupational cohort

Objectives

To examine the relationships of strenuous and hazardous working conditions and rotating shifts that involve night working with life expectancy in good perceived health and life expectancy without chronic disease.

Methods

The sample contained male gas and electricity workers from the French GAZEL cohort (n=13 393). Six measures of physical working conditions were examined: Self-reports from 1989 and 1990 of ergonomic strain, physical danger, rotating shifts that involve night working and perceived physical strain; company records of workplace injuries and a job-exposure matrix of chemical exposures. Partial healthy life expectancies (age 50–75) relating to (1) self-rated health and (2) chronic health conditions, obtained from annual questionnaires (1989–2014) and company records, were estimated using multistate life tables. The analyses were adjusted for social class and occupational grade.

Results

Participants with physically strenuous jobs and who had experienced industrial injuries had shorter partial life expectancy. More physically demanding and dangerous work was associated with fewer years of life spent in good self-rated health and without chronic conditions, with the exception of shift work including nights, where the gradient was reversed.

Conclusions

Strenuous and hazardous work may contribute to lost years of good health in later life, which has implications for individuals' quality of life as well as healthcare use and labour market participation.

Revisiting the health effects of psychological stress-its influence on susceptibility to ionizing radiation: a mini-review

Both psychological stress (PS) and ionizing radiation (IR) cause varied detrimental effects on humans. There has been no direct evidence so far showing PS alone could cause cancer; however, long-lasting PS may affect our overall health and ability to cope with cancer. Due to their living conditions and occupations, some people may encounter concurrent exposure to both PS and IR to a high extent. In addition to possible health effects resulting directly from exposure to IR on these people, fear of IR exposure is also a cause of PS. The question of whether PS would influence susceptibility to IR, radiocarcinogenesis in particular, is of great concern by both the academic world and the public. Recently, investigations using animal PS models demonstrated that PS could modulate susceptibility to IR, causing increased susceptibility to radiocarcinogenesis in Trp53-heterozygous mice, hematological toxicity in peripheral blood and elevated chromosome aberration (dicentrics) frequency in splenocytes of Trp53-wild-type mice. To actively reduce health risk from exposure to IR, further studies are needed to cumulate more evidence and provide insights into the mechanisms underlying the alterations in susceptibility due to PS modulation. This mini-review gives a general overview of the significance of PS effects on humans and experimental animals, with a special focus on summarizing the latest weight-of-evidence approaches to radiobiological studies on PS-induced alterations in susceptibility in experimental animal models. The susceptibility being investigated is mainly in the context of the impact of the modulatory effect of PS on radiocarcinogenesis; we seek to improve understanding of the combined effects of exposure to both PS and IR in order to facilitate, via active intervention, strategies for radiation risk reduction.

Chronic restraint-induced stress has little modifying effect on radiation hematopoietic toxicity in mice

Both radiation and stresses cause detrimental effects on humans. Besides possible health effects resulting directly from radiation exposure, the nuclear plant accident is a cause of social psychological stresses. A recent study showed that chronic restraint-induced stresses (CRIS) attenuated Trp53 functions and increased carcinogenesis susceptibility of Trp53-heterozygous mice to total-body X-irradiation (TBXI), having a big impact on the academic world and a sensational effect on the public, especially the residents living in radioactively contaminated areas. It is important to investigate the possible modification effects from CRIS on radiation-induced health consequences in Trp53 wild-type (Trp53wt) animals. Prior to a carcinogenesis study, effects of TBXI on the hematopoietic system under CRIS were investigated in terms of hematological abnormality in the peripheral blood and residual damage in the bone marrow erythrocytes using a mouse restraint model. Five-week-old male Trp53wt C57BL/6J mice were restrained 6 h per day for 28 consecutive days, and TBXI (4 Gy) was given on the 8th day. Results showed that CRIS alone induced a marked decrease in the red blood cell (RBC) and the white blood cell (WBC) count, while TBXI caused significantly lower counts of RBCs, WBCs and blood platelets, and a lower concentration of hemoglobin regardless of CRIS. CRIS alone did not show any significant effect on erythrocyte proliferation and on induction of micronucleated erythrocytes, whereas TBXI markedly inhibited erythrocyte proliferation and induced a significant increase in the incidences of micronucleated erythrocytes, regardless of CRIS. These findings suggest that CRIS does not have a significant impact on radiation-induced detrimental effects on the hematopoietic system in Trp53wt mice.

Type of retirement as a determinant of pre- and post-retirement hospital in-patient care use: a prospective study

BACKGROUND

We examined prospectively the use of all-cause hospital in-patient care among public sector employees by using a 3-year pre- and post-retirement study window.

METHODS

A total of 5269 participants of the Finnish Longitudinal Study of Municipal Employees had retired during January 1984 and July 2000. They had register-based data on retirement (non-disability retirement n = 3411, men 40%, and diagnose-specific disability retirement n = 1858, men 50%) and all-cause hospital in-patient admissions and discharges. Analyses were conducted using Generalized Estimating Equation model.

RESULTS

The prevalence of hospital care use for non-disability retirees remained stable during the 6-year study window. The rate ratio (RR) for hospital care use increased in the year prior to retirement for men and women who transitioned into disability retirement due to cardiovascular disease and for women with disability due to mental disease. The RRs for hospital care use in the post-retirement year decreased for men who retired due to cardiovascular disease or mental disorders and for women who retired due to cardiovascular or musculoskeletal diseases.

CONCLUSIONS

An increase in hospital care preceding retirement in major diagnosis-specific disability retirement groups was followed by various patterns of decrease in the need of care indicated a beneficial health effect of retirement.

Job demand and control in mid-life and physical and mental functioning in early old age: do childhood factors explain these associations in a British birth cohort?

OBJECTIVES

Adverse work-related exposures have been linked with decreased physical and mental functioning in later life, however, whether childhood factors explain the associations between work exposures and functioning is unknown. Our aim was to investigate if job demand and control in mid-life were related to self-reported physical and mental functioning in early old age and whether childhood factors explained these associations.

DESIGN

Prospective cohort study.

SETTING

England, Scotland and Wales.

PARTICIPANTS AND OUTCOME MEASURES

Data come from the UK Medical Research Council National Survey of Health and Development, a cohort with follow-up since birth in 1946. 1485 occupationally active study members had data available on job demand and control in mid-life and on physical and mental functioning assessed using the Short Form-36 questionnaire at 60-64 years.

RESULTS

Those with higher job control in mid-life had better physical functioning than those who reported lower job control (β 0.51, 95% CI 0.02 to 1.01, p=0.04 adjusted for adult confounders). Those with higher job demand in mid-life had poorer mental functioning (β -0.82, 95% CI -1.14 to -0.51, p<0.001). Associations between job control and mental functioning were similar but less pronounced. Adjustment for childhood factors (father's and mother's educational attainment, parents' interest in school at age 7 and cognitive ability at age 8) partially explained the association between job control and physical functioning, but did not explain the association between job demand and mental functioning.

CONCLUSIONS

Job demand and control in mid-life are differentially associated with mental and physical functioning in early old age and some of these associations may be partially explained by childhood factors.