Combined impact of lifestyle-related factors on total and cause-specific mortality among Chinese women: prospective cohort study.
BACKGROUND
Although cigarette smoking, excessive alcohol drinking, obesity, and several other well-studied unhealthy lifestyle-related factors each have been linked to the risk of multiple chronic diseases and premature death, little is known about the combined impact on mortality outcomes, in particular among Chinese and other non-Western populations. The objective of this study was to quantify the overall impact of lifestyle-related factors beyond that of active cigarette smoking and alcohol consumption on all-cause and cause-specific mortality in Chinese women.


RESULTS
We used data from the Shanghai Women's Health Study, an ongoing population-based prospective cohort study in China. Participants included 71,243 women aged 40 to 70 years enrolled during 1996-2000 who never smoked or drank alcohol regularly. A healthy lifestyle score was created on the basis of five lifestyle-related factors shown to be independently associated with mortality outcomes (normal weight, lower waist-hip ratio, daily exercise, never exposed to spouse's smoking, higher daily fruit and vegetable intake). The score ranged from zero (least healthy) to five (most healthy) points. During an average follow-up of 9 years, 2,860 deaths occurred, including 775 from cardiovascular disease (CVD) and 1,351 from cancer. Adjusted hazard ratios for mortality decreased progressively with an increasing number of healthy lifestyle factors. Compared to women with a score of zero, hazard ratios (95% confidence intervals) for women with four to five factors were 0.57 (0.44-0.74) for total mortality, 0.29 (0.16-0.54) for CVD mortality, and 0.76 (0.54-1.06) for cancer mortality. The inverse association between the healthy lifestyle score and mortality was seen consistently regardless of chronic disease status at baseline. The population attributable risks for not having 4-5 healthy lifestyle factors were 33% for total deaths, 59% for CVD deaths, and 19% for cancer deaths.


CONCLUSIONS
In this first study, to our knowledge, to quantify the combined impact of lifestyle-related factors on mortality outcomes in Chinese women, a healthier lifestyle pattern-including being of normal weight, lower central adiposity, participation in physical activity, nonexposure to spousal smoking, and higher fruit and vegetable intake-was associated with reductions in total and cause-specific mortality among lifetime nonsmoking and nondrinking women, supporting the importance of overall lifestyle modification in disease prevention. Please see later in the article for the Editors' Summary.
Nechuta
Sarah J
SJ
Division of Epidemiology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America.
Shu
Xiao-Ou
XO
Li
Hong-Lan
HL
Yang
Gong
G
Xiang
Yong-Bing
YB
Cai
Hui
H
Chow
Wong-Ho
WH
Ji
Butian
B
Zhang
Xianglan
X
Wen
Wanqing
W
Gao
Yu-Tang
YT
Zheng
Wei
W
D000328:Adult; D000368:Aged; D000428:Alcohol Drinking / Q000401:mortality; D044466:Asian People; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000401:mortality; D015331:Cohort Studies; D005260:Female; D006306:Health Surveys; D006801:Humans; D008019:Life Style; D008875:Middle Aged; D009026:Mortality / Q000208:ethnology / Q000639:trends*; D009369:Neoplasms / Q000401:mortality; D011446:Prospective Studies; D012907:Smoking / Q000401:mortality; D049629:Waist-Hip Ratio