Purpose: To investigate quality of life (QOL) and associated factors in centenarians, we conducted a visitation interview survey for all male and one half of the female centenarians living in Japan, and studied QOL, lifestyle and health status.
Methods: All the male centenarians and a randomly-sampled half of the female centenarians living in Japan were included in the study based on the National Census. Finally, 556 male and 1341 female centenarians participated in the present visitation interview survey and were studied using a structured questionnaire. QOL was assessed from 3 aspects; activities of daily life (ADL), cognitive function (CF) and mental health (MH).
Results: Individuals having superior ADL accounted for 30.9% of the male and 13.6% of the female centenarians, those with superior CF were 58.1% and 35.6%, respectively, and those with superior MH were 39.2% and 26.8%, providing evidence that superior QOL was more dominant in males than in females. There were no effects of residential areas (north, east, middle, west, southwest and south of Japan) on the prevalence of ADL, CF and MH. Multiple logistic regression analyses conducted independently, for ADL, CF and MH as dependent valuables revealed that habitual exercise, less decline in visual ability and preservation of masticating ability were associated with better results for these 3 aspects of male centenarians' QOL, and that habitual exercise, less decline in visual ability, spontaneous awakening in the morning, good appetite and having cohabitating family members were associated with superior QOL in the females, suggesting that more factors are operating in the latter.
Conclusions: Several lifestyle factors were found to be associated with preservation of QOL in centenarians in Japan. These results should facilitate establishing a public health and welfare policy for the most senior citizens, a group that has been increasing in Japan.