Psychological Resources and Glucoregulation in Japanese Adults: Findings from MIDJA

Abstract

Objective

To examine associations between glucoregulation and three categories of psychological resources: hedonic well-being (i.e., life satisfaction, positive affect), eudaimonic well-being (i.e., personal growth, purpose in life, ikigai) and interdependent well-being (i.e., gratitude, peaceful disengagement, adjustment) among Japanese adults. The question is important given increases in rates of type 2 diabetes in Japan in recent years, combined with the fact that most prior studies linking psychological resources to better physical health have utilized Western samples.

Methods

Data came from the Midlife in Japan (MIDJA) Study involving randomly selected participants from the Tokyo metropolitan area, a subsample of whom completed biological data collection ( N=382; 56.0% female; M(SD) _age = 55.5(14.0) years). Glycosylated hemoglobin (HbA1c) was the outcome. Models adjusted for age, gender, educational attainment, smoking, alcohol, chronic conditions, body mass index, use of anti-diabetic medication, and negative affect.

Results

Purpose in life (β = −.102, p = .022) was associated with lower HbA1c, and peaceful disengagement (β = .124, p = .004) was associated with higher HbA1c in fully adjusted models. Comparable to the effects of BMI, a one standard deviation change in well-being was associated with a .1% change in HbA1c.

Conclusions

Associations among psychological resources and glucoregulation were mixed. Healthy glucoregulation was evident among Japanese adults with higher levels of purpose in life and lower levels of peaceful disengagement, thereby extending prior research from the U.S. The results emphasize the need for considering sociocultural contexts in which psychological resources are experienced in order to understand linkages to physical health.