Impact of walking on life expectancy and lifetime medical expenditure: the Ohsaki Cohort Study
- Masato Nagai1,
- Shinichi Kuriyama1,2,
- Masako Kakizaki1,
- Kaori Ohmori-Matsuda1,
- Toshimasa Sone1,
- Atsushi Hozawa1,4,
- Miyuki Kawado5,
- Shuji Hashimoto5,
- Ichiro Tsuji1
- 1Division of Epidemiology, Department of Public Health and Forensic Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
- 2Department of Molecular Epidemiology, Genome Research Center, Tohoku University Graduate School of Medicine, Sendai, Japan
- 3Department of Environment and Genome Research Center, Tohoku University Graduate School of Medicine, Sendai, Japan
- 4Department of Public Health, Yamagata University Graduate School of Medical Science, Yamagata, Japan
- 5Department of Hygiene, Fujita Health University School of Medicine, Toyoake, Japan
- Correspondence to Dr Masato Nagai;
- Received 28 June 2011
- Accepted 25 August 2011
- Published 30 September 2011
Objective People who spend a longer time walking have lower demands for medical care. However, in view of their longer life expectancy, it is unclear whether their lifetime medical expenditure increases or decreases. The present study examined the association between time spent walking, life expectancy and lifetime medical expenditure.
Method The authors followed up 27 738 participants aged 40–79 years and prospectively collected data on their medical expenditure and survival covering a 13-year-period. Participants were classified into those walking <1 and ≥1 h per day. The authors constructed life tables and estimated the life expectancy and lifetime medical expenditure from 40 years of age using estimate of multiadjusted mortality and medical expenditure using a Poisson regression model and linear regression model, respectively.
Results Participants who walked ≥1 h per day have a longer life expectancy from 40 years of age than participants who walked <1 h per day. The multiadjusted life expectancy for those who walked ≥1 h per day was 44.81 years, significantly lower by 1.38 years in men (p=0.0073) in men and 57.78 years in women, non-significantly lower by 1.16 years in women (p=0.2351). In addition to their longer life expectancy, participants who walked ≥1 h per day required a lower lifetime medical expenditure from 40 years of age than participants who walked <1 h per day. The multiadjusted lifetime medical expenditure for those who walked ≥1 h per day was £99 423.6, significantly lower by 7.6% in men (p=0.0048) and £128 161.2, non-significantly lower by 2.7% in women (p=0.2559).
Discussion Increased longevity resulting from a healthier lifestyle does not necessarily translate into an increased amount of medical expenditure throughout life. Encouraging people to walk may extend life expectancy and decrease lifetime medical expenditure, especially for men.
Correction notice The “To cite: …” information and running footer in this article have been updated with the correct volume number (volume 1).
To cite: Nagai M, Kuriyama S, Kakizaki M, et al. Impact of walking on life expectancy and lifetime medical expenditure: the Ohsaki Cohort Study. BMJ Open 2011;1:e000240. doi:10.1136/bmjopen-2011-000240
Funding This study was supported by a Health Sciences Research Grant for Health Services (H21-Choju-Ippan-001, H20-Junkankitou (Seisyu)-Ippan-013, H22- Junkankitou (Seisyu)-Ippan-012, H23- Junkankitou (Seisyu)-Ippan-005), Ministry of Health, Labour and Welfare, Japan. MN is a recipient of a Research Fellowships of the Japan Society for the Promotion of Science for Young Scientists.
Competing interest None.
Patient consent Obtained.
Ethical approval Ethics approval was provided by the Ethics Committee of Tohoku University School of Medicine.
Contributors All authors contributed to the design of the study. MN, SK, MK, KO-M, TS and IT carried out the data collection. MN, SK, AH, MK and SH carried out the data analysis. MN, MK, KO-M, TS, AH, MK and SH wrote the report. SK and IT carried out a critical revision of the manuscript. All authors approved the final version of the report for submission.
Provenance and peer review Not commissioned; externally peer reviewed.
Data sharing statement No additional data available.
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