title: Physical activity levels and differences in the prevalence of diabetes between the United States and Canada.
abstract: OBJECTIVE
  To examine the American-Canadian difference in physical activity and its association with diabetes prevalence.
  
  
  METHODS
  We used cross-sectional data from nationally representative samples of adults (8688 persons aged > or =18 years) participating in the 2004 Joint Canada/U.S. Survey of Health. Using data on up to 22 activities in the past 3 months, we defined 3 physical activity groups (in metabolic equivalents-hours/day) as low (<1.5), moderate (1.5-2.9), and high (> or =3.0). We employed logistic regression models in our analyses.
  
  
  RESULTS
  Self-reported diabetes prevalence was 7.6% in the U.S. and 5.4% in Canada. The prevalence of low physical activity was considerably higher in the U.S. (70.9%) than in Canada (52.3%), while levels of moderate and high physical activity were higher in Canada (24.6% and 23.1%, respectively) than in the U.S. (14.3% and 14.8%, respectively). Using nationality (Canada as reference) to predict diabetes status, the adjusted odds ratio was 1.48 (95%CI, 1.22-1.79), and became 1.38 (95%CI, 1.15-1.66) when additionally adjusting for physical activity level. We estimate that 20.8% of the U.S.-Canada difference in diabetes prevalence is associated with physical activity.
  
  
  CONCLUSIONS
  The difference in the prevalence of diabetes between U.S. and Canadian adults may be partially explained by differences in physical activity between the two countries.
authors.affiliation: Division of Diabetes Translation, Centers for Disease Control and Prevention, 4770 Buford Highway NE, Atlanta, GA 30341, USA. xbz2@cdc.gov
authors.forename: Xuanping
authors.initials: X
authors.lastname: Zhang
authors.forename: Linda S
authors.initials: LS
authors.lastname: Geiss
authors.forename: Carl J
authors.initials: CJ
authors.lastname: Caspersen
authors.forename: Yiling J
authors.initials: YJ
authors.lastname: Cheng
authors.forename: Michael M
authors.initials: MM
authors.lastname: Engelgau
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Johnson
authors.forename: Ronald C
authors.initials: RC
authors.lastname: Plotnikoff
authors.forename: Edward W
authors.initials: EW
authors.lastname: Gregg
mesh_terms: D000328:Adult; D002170:Canada / Q000453:epidemiology; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D003920:Diabetes Mellitus / Q000453:epidemiology / Q000517:prevention & control; D004734:Energy Metabolism; D015444:Exercise / Q000502:physiology; D005260:Female; D015438:Health Behavior; D006306:Health Surveys; D006801:Humans; D007182:Income / Q000706:statistics & numerical data; D016015:Logistic Models; D008297:Male; D055686:Metabolic Equivalent; D008875:Middle Aged; D015999:Multivariate Analysis; D015995:Prevalence; D011795:Surveys and Questionnaires; D014481:United States / Q000453:epidemiology