Green Tea Consumption and Mortality among Japanese Elderly People: The Prospective Shizuoka Elderly Cohort

Suzuki, Etsuji; Yorifuji, Takashi; Takao, Soshi; Komatsu, Hirokazu; Sugiyama, Masumi; Ohta, Toshiki; Ishikawa-Takata, Kazuko; Doi, Hiroyuki

doi:10.1016/j.annepidem.2009.06.003

« Previous Next »Annals of Epidemiology
Volume 19, Issue 10 , Pages 732-739, October 2009

Green Tea Consumption and Mortality among Japanese Elderly People: The Prospective Shizuoka Elderly Cohort

Etsuji Suzuki, MD, PhD
- Department of Epidemiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Japan
- Address correspondence reprint requests to: Etsuji Suzuki, MD, PhD, Department of Epidemiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama. 700-8558, Japan. Tel: +81(JPN)-86-223-7151 (ext. 7175). Fax: +81(JPN)-86-235-7178.
Takashi Yorifuji, MD, PhD
- Department of Epidemiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Japan
Soshi Takao, MD, PhD
- Department of Epidemiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Japan
Hirokazu Komatsu, MD, PhD
- Department of Epidemiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Japan
- Division of Community Care, Saku Central Hospital, Nagano, Japan
Masumi Sugiyama, BA
- Tobu Child Support Center of Shizuoka Prefecture, Shizuoka, Japan
Toshiki Ohta, MD, PhD
- National Hospital for Geriatric Medicine, National Center for Geriatrics and Gerontology, Aichi, Japan
Kazuko Ishikawa-Takata, PhD
- Program of Health Promotion and Exercise, National Institute of Health and Nutrition, Tokyo, Japan
Hiroyuki Doi, MD, PhD
- Department of Epidemiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Japan

Received 31 October 2008; accepted 11 June 2009. published online 23 July 2009.

Purpose

To investigate the association between green tea consumption and mortality from all causes, cancer, and cardiovascular disease (CVD) among elderly people.

Methods

In a population-based, prospective cohort study, a total of 14,001 elderly residents (aged 65–84 years), randomly chosen from all 74 municipalities in Shizuoka, Japan, completed questionnaires that included items about frequency of green tea consumption. They were followed for up to 6 years, from December 1999 to March 2006. Consequently, 12,251 subjects were analyzed to estimate the hazard ratios (HRs) for all-cause mortality, cancer, and CVD.

Results

Among 64,002 person-years, 1,224 deaths were identified (follow-up rate, 71.6%). The multivariate HRs and 95% confidence intervals (CIs) for CVD mortality compared those who consumed seven or more cups per day with those who consumed less than one cup per day, were 0.24 (0.14–0.40), 0.30 (0.15–0.61), and 0.18 (0.08–0.40) for total participants, men, and women, respectively. Although green tea consumption was not inversely associated with cancer mortality, green tea consumption and colorectal cancer mortality were inversely associated with a moderate dose-response relationship.

Conclusions

Green tea consumption is associated with reduced mortality from all causes and CVD. This study also suggests that green tea could have protective effects against colorectal cancer.

Key Words: Aged, Cohort Studies, Japan, Prospective Studies, Tea

Selected Abbreviations and Acronyms: CVD, cardiovascular disease, ICD, International Classification of Diseases, BMI, body mass index, HR, hazard ratio, CI, confidence interval