Impact of walking upon medical care expenditure in Japan: the Ohsaki Cohort Study.
BACKGROUND
Physical activity is expected to reduce medical costs by lowering the risk for a variety of chronic diseases. However, little is known about the actual magnitude of medical cost saved by physical activity. We attempted to quantify the association between time spent walking and medical care costs, based on a 4-year prospective observation of National Health Insurance (NHI) beneficiaries in rural Japan.


METHODS
In 27 431 Japanese men and women, aged 40-79 years, who had no functional limitation or conditions interfering with physical activity at the baseline survey in 1994, we ascertained all hospitalizations, outpatient visits, and the costs through computerized linkage with NHI claims history files between January 1995 and December 1998.


RESULTS
Medical costs significantly reduced with longer time spent walking. Per capita medical cost was pound 111.80 per month (95% CI: 109.3, 114.2) in those who walked for < or =30 minutes/day, pound 108.10 (95% CI: 105.7, 110.5) in those who walked for 30 minutes-1 hour, and pound 97.30 (95% CI: 95.5, 99.0) in those who walked for > or =1 hour, after multivariate adjustment of potential confounders.


CONCLUSIONS
This prospective study in Japan indicated that time spent walking was significantly associated with lower medical costs.
Tsuji
Ichiro
I
Department of Public Health, Tohoku University School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan. tsuji1@mail.cc.tohoku.ac.jp
Takahashi
Kohko
K
Nishino
Yoshikazu
Y
Ohkubo
Takayoshi
T
Kuriyama
Shinichi
S
Watanabe
Yoko
Y
Anzai
Yukiko
Y
Tsubono
Yoshitaka
Y
Hisamichi
Shigeru
S
D000328:Adult; D000368:Aged; D015331:Cohort Studies; D005260:Female; D017048:Health Care Costs / Q000706:statistics & numerical data*; D006302:Health Services Research; D006760:Hospitalization / Q000191:economics / Q000706:statistics & numerical data; D006801:Humans; D007564:Japan; D008297:Male; D008498:Medical Record Linkage; D008875:Middle Aged; D010044:Outpatient Clinics, Hospital / Q000191:economics / Q000706:statistics & numerical data; D011446:Prospective Studies; D013997:Time Factors; D016138:Walking / Q000706:statistics & numerical data*