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Declining longevity advantage and low birthweight in Okinawa
1Graduate School of Health Sciences, University of the Ryukyus, 207, Uehara, Nishihara, Okinawa, Japan 903-0215. b987390@med.u-ryukyu.ac.jp
Asia-Pacific Journal of Public Health
|June 18, 2009
Summary
Okinawan longevity advantage declined as low birthweight rates increased. This study suggests a cohort effect, where post-war low birthweight infants now face higher non-communicable disease risks, impacting life expectancy.
Area of Science:
- Gerontology
- Public Health
- Epidemiology
Background:
- Okinawa historically held the highest life expectancy in Japan for three decades.
- This longevity advantage significantly declined around the year 2000, particularly for males.
- Recent trends indicate a potential shift in Okinawan population health dynamics.
Purpose of the Study:
- To investigate the cohort effect of low birthweight on the declining longevity advantage in Okinawa.
- To explore the link between increased non-communicable diseases and birthweight in Okinawan cohorts.
- To understand the factors contributing to the loss of Okinawa's historical life expectancy advantage.
Main Methods:
- Observational study utilizing existing demographic and health statistics.
- Analysis of life expectancy, mortality rates, and low birthweight data.
- Comparison of Okinawan data with Japanese mainland statistics.
Main Results:
- Okinawan males lost their longevity advantage over mainland Japan by 2000; female life expectancy also declined.
- A reversed mortality ratio for heart disease suggests a cohort effect, with younger Okinawans showing higher rates.
- Okinawa's low birthweight rate is 20% higher than mainland Japan's.
Conclusions:
- The decline in Okinawan longevity is linked to the post-World War cohort experiencing higher low birthweight rates.
- Increased non-communicable disease rates in this cohort appear to be a primary factor in the diminished life expectancy advantage.
- Public health strategies may need to address the long-term health impacts of low birthweight in Okinawa.
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