Odagiri Youichi, Uchida Hiroyuki, Koyama Katsuhiro
Division of Public Health Nursing, Graduate school of Yamanashi Prefectural University.
Nihon Koshu Eisei Zasshi. 2013 Jun;60(6):356-69.
The increase in the overweight or underweight student population in Japanese schools is an important health issue. To assess the independent effects of age, period, and birth cohorts, we analyzed trends in the rates of overweight and underweight students from 1977 to 2006 using a Bayesian age-period-cohort (APC) analysis. Additionally, we predicted the rates overweight and underweight students in 2007-2016.
We created a data set of the rates of overweight and underweight students aged 6-14 years using the annual school health survey report data. We then analyzed a cohort table that plotted age against calendar time using a Bayesian APC model. We also made a prediction of the rates of overweight and underweight students in 2007-2016.
For overweight students, the age effect increased from 6 to 11 years of age for male students and from 6 to 12 years of age for female students; thereafter, the effects decreased. The period effects consistently increased until late 1990, and decreased thereafter for both male and female students. The cohort effects increased for male students born between 1963 and 1969, and later decreased for those born in 1981. However, this trend for male students later increased. For female students, the cohort effects decreased for those born between 1963 and 1975, and later increased for those born in 1990, indicating a plateau or slight increase in the trend. For underweight students, the age effect in male students increased from 7 to 10 years of age, and then plateaued; whereas, the age effect increased from 7 to 12 years of age for female students before reaching a plateau. The period effects increased consistently by 2000 and decreased slightly in both male and female students. The birth cohort effect in male students increased for those born after the mid-1980s, and then plateaued in the early 1990s. The cohort effect increased for female students born after 1984, and then plateaued in 1993. The projections for the rates of overweight and underweight student population indicated a steady trend until 2016.
The rate of overweight and underweight students was strongly influenced by age; however, period and birth cohort also played a role. The projections for the rates of overweight and underweight students indicated a steady trend until 2016. These results suggest that strategies based on age-, period-, and cohort-specific measures may be required for future interventions for preventing overweight and underweight among students.
日本学校中超重或体重过轻学生人数的增加是一个重要的健康问题。为了评估年龄、时期和出生队列的独立影响，我们使用贝叶斯年龄-时期-队列（APC）分析方法，分析了1977年至2006年超重和体重过轻学生比例的趋势。此外，我们还预测了2007年至2016年超重和体重过轻学生的比例。
我们利用年度学校健康调查报告数据，创建了一个6至14岁超重和体重过轻学生比例的数据集。然后，我们使用贝叶斯APC模型分析了一个将年龄与日历时间相对应的队列表。我们还对2007年至2016年超重和体重过轻学生的比例进行了预测。
对于超重学生，男生的年龄效应在6至11岁时增加，女生在6至12岁时增加；此后，效应下降。时期效应在1990年代后期之前持续增加，此后男女生的效应均下降。1963年至1969年出生的男生队列效应增加，1981年出生的男生队列效应随后下降。然而，男生的这一趋势后来又有所增加。对于女生，1963年至1975年出生的队列效应下降，1990年出生的队列效应随后增加，表明该趋势趋于平稳或略有上升。对于体重过轻的学生，男生的年龄效应在7至10岁时增加，然后趋于平稳；而女生的年龄效应在7至12岁时增加，之后趋于平稳。时期效应在2000年之前持续增加，男女生均略有下降。1980年代中期以后出生的男生出生队列效应增加，然后在1990年代初趋于平稳。1984年以后出生的女生队列效应增加，然后在1993年趋于平稳。超重和体重过轻学生比例的预测表明，到2016年趋势稳定。
超重和体重过轻学生的比例受年龄的影响很大；然而，时期和出生队列也起到了一定作用。超重和体重过轻学生比例的预测表明，到2016年趋势稳定。这些结果表明，未来预防学生超重和体重过轻的干预措施可能需要基于年龄、时期和队列特定的措施。
