Psychological Resources and Glucoregulation in Japanese Adults: Findings From MIDJA
Objective: To examine associations between glucoregulation and 3 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. Method: Data came from the Midlife in Japan 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 (BMI), use of antidiabetic medication, and negative affect. Results: Purpose in life (β = −.104, p = .021) was associated with lower HbA1c, and peaceful disengagement (β = .129, p = .003) was associated with higher HbA1c in fully adjusted models. Comparable to the effects of BMI, a 1 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 United States. The results emphasize the need for considering sociocultural contexts in which psychological resources are experienced in order to understand linkages to physical health.