Multiple roles and all-cause mortality: the Japan Collaborative Cohort Study

Positive psychological factors and the risk of pneumonia-associated mortality: Japan Collaborative Cohort Study

OBJECTIVE

To examine the association between positive psychological factors and the risk of pneumonia-associated mortality in a large prospective Japanese cohort.

METHODS

The Japan Collaborative Cohort Study assessed 64,231 participants (26,293 men and 37,938 women), aged 40-79 years, without a history of stroke, myocardial infarction, cancer or tubercules at baseline (1988-1990). We used self-administered questionnaires about lifestyle, medical history, and mental states, including three positive psychological factors, and followed-up for mortality outcomes until the end of 2009. The Cox proportional hazard model was used to calculate the multivariable hazard ratios (HRs) with 95% confidence intervals (CIs) of pneumonia-associated mortality after adjustment for potential confounding factors, mutually positive psychological factors, and consideration for the competing risk.

RESULTS

Having Ikigai (in Japanese) was inversely associated with the risk of pneumonia-associated mortality in both men and women; the multivariable HRs (95% CIs) for high versus low levels were 0.68 (0.48-0.97), P trend =0.090 and 0.66 (0.43-1.00), P trend =0.146, respectively. Such inverse associations were more pronounced in working men and non-working women; the multivariable HRs (95% CIs) for high versus low levels were 0.52 (0.32-0.85), P trend =0.010 and 0.59 (0.37-0.94), P trend =0.079, respectively. Being relied upon by others and Enjoyment of life was not associated with the risk in both genders.

CONCLUSION

Having Ikigai was associated with a lower risk of pneumonia-associated mortality in both genders, especially in working men and non-working women.

Social role conflict predicts stimulated cytokine production among men, not women

OBJECTIVE

To assess whether perceived role conflict is associated with stimulated pro-inflammatory cytokine production and glucocorticoid sensitivity, and whether these associations are moderated by sex.

METHODS

153 healthy adults (aged 45.8±5.5years, 78% female) listed their 3 main social roles and indicated the amount of role conflict they perceived between each pair of social roles. Subsequently, participants underwent blood draws and leukocyte response to microbial challenge and glucocorticoid sensitivity were assessed by incubating whole blood with lipopolysaccharide (LPS) in the presence or absence of hydrocortisone. Stimulated levels of Interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor alpha (TNFα) were measured.

RESULTS

Multiple regression analyses controlling for sociodemographics revealed significant sex×role conflict interactions for LPS-stimulated production of IL-1β, IL-6, and TNFα (all interaction ps<0.05), and a marginal interaction on LPS-stimulated IL-8 production (interaction p<0.10). Greater perceived role conflict was associated with greater pro-inflammatory cytokine production in response to microbial stimulation only among men, not women. There also were significant sex×role conflict interactions with respect to glucocorticoid sensitivity for IL-1β, IL-6, and TNFα production (all interaction ps<0.05) and a marginal interaction for IL-8 (interaction p<0.10). Greater perceived role conflict was unrelated to glucocorticoid sensitivity among women, but associated with less sensitivity to glucocorticoid signaling among men.

CONCLUSIONS

Perceived social role conflict, indicating greater perceived demand across multiple social roles, may take a greater toll on the regulation of inflammatory processes among men compared to women.