title: Physical activity level and incident type 2 diabetes among Chinese adults.
abstract: OBJECTIVE
  The objective is to examine the association between physical activity level (PAL) and incident type 2 diabetes among middle-age and older Chinese men and women in urban China.
  
  
  METHODS
  This prospective study included 6348 participants (age 35 to 74 yr) who were free of diabetes and cardiovascular disease at baseline. PAL was estimated on the basis of self-reported overall physical activity on a typical day. According to PAL, participants were classified into four groups: sedentary (PAL, 1.00-1.39), low active (PAL, 1.40-1.59), active (PAL, 1.60-1.89), and very active (PAL, >1.89). The association of PAL with incident diabetes was examined by Cox proportional hazards model.
  
  
  RESULTS
  During 7.9 yr of follow-up (50,293 person-years), 478 incident cases of type 2 diabetes were identified. After adjustment for age, sex, geographic region, educational level, smoking, alcohol use, and family history of diabetes, the HR (95% CI) values for type 2 diabetes across increasing categories of PAL were 1.00 (reference), 0.82 (0.62-1.09), 0.63 (0.47-0.83), and 0.47 (0.36-0.61), respectively (P for trend <0.0001). Additional adjustment for baseline body mass index or waist circumference attenuated the magnitude of risk reduction, but it remained significant. The inverse association between PAL and risk of incident diabetes was persistent in subgroup analyses according to age, sex, hypertension, smoking, body mass index, waist circumference, and fasting plasma glucose level.
  
  
  CONCLUSIONS
  Higher PAL is associated with substantial reduction in risk of type 2 diabetes. Our findings suggest the importance of a physically active lifestyle in the prevention of diabetes.
authors.affiliation: 1Department of Evidence Based Medicine, Fuwai Hospital, National Center of Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, CHINA; 2Department of Epidemiology, Guangdong Provincial People's Hospital and Cardiovascular Institute, Guangzhou, CHINA; 3Department of Cardiology, Fujian Provincial People's Hospital, Fuzhou, CHINA; 4Division of Chronic Disease Prevention and Control, Sichuan Centre for Disease Control and Prevention, Chengdu, CHINA; 5Division of Chronic Disease Prevention and Control, Guangxi Centre for Disease Control and Prevention, Nanning, CHINA; 6Department of Cardiology, Yuxian People's Hospital, Yuxian, CHINA.
authors.forename: Sen
authors.initials: S
authors.lastname: Fan
authors.forename: Jichun
authors.initials: J
authors.lastname: Chen
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Huang
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.forename: Liancheng
authors.initials: L
authors.lastname: Zhao
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Liu
authors.forename: Jianxin
authors.initials: J
authors.lastname: Li
authors.forename: Jie
authors.initials: J
authors.lastname: Cao
authors.forename: Ling
authors.initials: L
authors.lastname: Yu
authors.forename: Ying
authors.initials: Y
authors.lastname: Deng
authors.forename: Naying
authors.initials: N
authors.lastname: Chen
authors.forename: Dongshuang
authors.initials: D
authors.lastname: Guo
authors.forename: Dongfeng
authors.initials: D
authors.lastname: Gu
mesh_terms: D000328:Adult; D000368:Aged; D002681:China / Q000453:epidemiology; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology* / Q000517:prevention & control; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D014504:Urban Health