The relationship between personality, life events and healthy longevity: A comparison of U.S. and Japanese centenarians.

摘要

This dissertation comprises of three manuscripts and compares a population-based sample of 239 U.S. centenarians from the Georgia Centenarians Study to 304 Japanese centenarians from the Tokyo Centenarian Study. The first study compared the most important life events reported by U.S. and Japanese centenarians. Two open-ended life events questions were categorized and grouped into different life event domains. Several cross-tabulations were computed to investigate culture and gender differences in most important life event domains. The main results suggest that events related to marriage were the most frequent event domains mentioned by U.S. centenarians. The Japanese sample was more likely to report historical events. Men from the U.S. were more likely to report events related to work and retirement compared to U.S. women, and U.S. women reported events related to family as the most important life events when compared to U.S. men. Japanese women considered events related to marriage, death and grief as the most important life events when compared to Japanese men. In addition, Japanese men reported events related to work and retirement as the most important life events. A cross-cultural difference was found in life events. U.S. centenarians were more likely to mention positive experiences related to marriage and children, whereas Japanese centenarians reported mostly negative and traumatic experiences such as historical events, death/grief, and work/retirement events. The second study investigated demographic and cultural mean differences among five NEO personality traits. In addition, it identified and compared across culture centenarians' personality trait profiles in U.S. and Japanese centenarians. Several one-way analyses of variance were performed and latent profile analyses were conducted to identify personality trait profiles in centenarians from the United States and Japan. Two personality profiles were identified in both samples: the "resilient group" (higher scores on Agreeableness and Extraversion, and lower mean scores on Neuroticism, Conscientiousness, and Openness compared to the population means) and the "non-resilient group" (higher scores on Neuroticism and lower scores on Extraversion, Openness, Agreeableness and Conscientiousness compared to the population means). No cultural differences in personality profiles were found. The third study investigated the effect of personality and life events on mental and cognitive health and the mediating and moderating effects of personality and life events on mental and cognitive health. Several structural equation models were computed for each culture to test the relationship of personality, life events (i.e., marriage and historical events), and mental and cognitive health. Results from structural equation modeling indicated that centenarians with a resilient personality had better mental health in both samples. No significant mediating and moderating effects of personality were found in either sample. Japanese centenarians who reported marriage as the most important event had better mental health compared to Japanese centenarians who did not report marriage as the most important event. Japanese centenarians reporting historical events had poor mental health compared to Japanese centenarians not mentioning an historical event. In conclusion, the results indicate that Japanese centenarians mentioning historical events were more at risk for mental health problems than U.S. centenarians.