Psychological factors and mortality risk in a rural area of Japan

Yonago Acta Med. 2014 Jun;57(2):73-83. Epub 2014 Jul 30.

Abstract

Background: The purpose of this study is to assess the association between psychological factors and mortality risk from all causes.

Methods: We used follow-up data for 4,181 persons from 40 to 79 years over a period of 17.6 years from one part of the Japan Collaborative Cohort Study (JACC Study). The status of the individuals comprising the data of the study as of the end of December 2006 was determined from their registration cards and death records. We calculated the proportions of selected variables among 5 psychological factors by sex. Cox's proportional hazards model was used to evaluate the associations between psychological factors and mortality risk from all causes. Data were adjusted for age, medical history, education, job status, marital status, drinking, smoking, physical activity, sleeping duration, body mass index and breakfast.

Results: During the follow-up period, a total of 791 deaths were recorded. Men who reported feelings of being trusted had a decreased risk for mortality risk from all causes compared with the risk of those who reported "maybe", whereas those without feelings of being trusted had increased risk for mortality risk from all causes.

Conclusion: This study suggests that the absence of feelings of being trusted increases the risk of all causes of mortality among middle-aged and elderly men in a rural area. Our findings suggest that interpersonal relationships comprise an important factor in longevity.

Keywords: feeling of being trusted; long-term cohort study; mortality risk; psychological factor; survival analysis.