title: Body mass index and all-cause mortality in a large Chinese cohort.
abstract: BACKGROUND
  Obesity is known to be associated with an increased risk of death, but current definitions of obesity are based on data from white populations. We examined the association between body mass index (BMI) and the risk of death in a large population of adult Chinese people.
  
  
  METHODS
  We examined the association between body mass index (BMI) and all-cause mortality prospectively among 58,738 men and 65,718 women aged 20 years and older enrolled in 1998-1999 from four national health screening centres in Taiwan. We used Cox proportional hazards regression analyses to estimate the relative risks of all-cause mortality for different BMI categories during a maximum follow-up of 10 years.
  
  
  RESULTS
  A total of 3947 participants died during the follow-up period. The lowest risk of death was observed among men and women who had a BMI of 24.0-25.9 (mean 24.9). After adjustment for age, smoking status, alcohol intake, betel-nut chewing, level of physical activity, income level and education level, we observed a U-shaped association between BMI and all-cause mortality. Similar U-shaped associations were observed when we analyzed data by age (20-64 or ≥ 65 years), smoking (never, < 10 pack-years or ≥ 10 pack-years) and presence of a pre-existing chronic disease, and after we excluded deaths that occurred in the first three years of follow-up.
  
  
  CONCLUSIONS
  BMI and all-cause mortality had a U-shaped association among adult Chinese people in our study. The lowest risk of death was among adults who had a BMI of 24.0-25.9 (mean 24.9). Our findings do not support the use of a lower cutoff value for overweight and obesity in the adult Chinese population.
authors.affiliation: Department of Family Medicine, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Wen-Yuan
authors.initials: WY
authors.lastname: Lin
authors.forename: Shin-Li
authors.initials: SL
authors.lastname: Tsai
authors.forename: Jeanine B
authors.initials: JB
authors.lastname: Albu
authors.forename: Cheng-Chieh
authors.initials: CC
authors.lastname: Lin
authors.forename: Tsai-Chung
authors.initials: TC
authors.lastname: Li
authors.forename: F Xavier
authors.initials: FX
authors.lastname: Pi-Sunyer
authors.forename: Pei-Kun
authors.initials: PK
authors.lastname: Sung
authors.forename: Kuo-Chin
authors.initials: KC
authors.lastname: Huang
mesh_terms: D000328:Adult; D000368:Aged; D015992:Body Mass Index; D002423:Cause of Death; D015331:Cohort Studies; D005260:Female; D015438:Health Behavior; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000401:mortality*; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D012959:Socioeconomic Factors; D013624:Taiwan; D055815:Young Adult