Survey of Midlife in Japan (MIDJA): Biomarker Project, 2009-2010

The MIDJA Biomarker study obtained biological assessments from a subsample (n=382) of MIDJA Survey (ICPSR 30822) respondents (N=1027). Participants traveled to a clinic near the University of Tokyo campus where Biomarker data (vital signs, morphometric assessments, blood assays, and medication data) were obtained. Participants also provided daily saliva samples for cortisol assessment and completed a self-administered medical history questionnaire. The questionnaire included assessments of conditions and symptoms, major health and life events, nutrition/diet, and additional psychosocial measures (anxiety, depression, relationship quality, control etc.). These measures parallel those in a national longitudinal sample of midlife Americans known as MIDUS (ICPSR 4652: MIDUS II and ICPSR 2760: MIDUS I). The central objective is to compare the Japanese sample (MIDJA) with the United States sample (MIDUS) to test the hypotheses regarding cultural differences in aging health and well-being as well as in how psychosocial factors are linked with biological factors known to influence profiles of disease and disability.