title: Physical activity and television watching in relation to risk of type 2 diabetes: the Black Women's Health Study.
abstract: Few modifiable risk factors for type 2 diabetes have been documented in the high-risk population of US black women. The authors used data from 45,668 black women aged 21-69 years, followed biennially from 1995 to 2005 in the Black Women's Health Study, to estimate incidence rate ratios for type 2 diabetes comparing various levels of physical activity and television watching. Cox proportional hazards models were used to control confounding factors. During 10 years of follow-up, 2,928 incident cases of type 2 diabetes were identified. Vigorous activity was inversely associated with type 2 diabetes risk (P(trend)<0.0001); the incidence rate ratio for >or= 7 hours per week was 0.43 (95% confidence interval (CI): 0.31, 0.59) relative to no activity. Brisk walking for >or= 5 hours per week was associated with reduced type 2 diabetes risk (incidence rate ratio=0.67, 95% CI: 0.49, 0.92) relative to no walking. Television watching was associated with an increased type 2 diabetes risk: The incidence rate ratio was 1.86 (95% CI: 1.54, 2.24) for >or= 5 hours relative to <1 hour of television per day, independent of physical activity. These observational data suggest that black women might reduce their risk of developing type 2 diabetes by increasing their time spent walking or engaged in vigorous physical activity and by limiting television watching.
authors.affiliation: Slone Epidemiology Center, Boston University, Boston, Massachusetts 02215, USA.
authors.forename: Supriya
authors.initials: S
authors.lastname: Krishnan
authors.forename: Lynn
authors.initials: L
authors.lastname: Rosenberg
authors.forename: Julie R
authors.initials: JR
authors.lastname: Palmer
mesh_terms: D000328:Adult; D001741:Black or African American / Q000523:psychology / Q000706:statistics & numerical data*; D000368:Aged; D015992:Body Mass Index; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology* / Q000517:prevention & control; D015444:Exercise; D005260:Female; D015438:Health Behavior / Q000208:ethnology; D006801:Humans; D015994:Incidence; D007899:Leisure Activities / Q000523:psychology; D008875:Middle Aged; D018670:Monitoring, Ambulatory / Q000379:methods; D009043:Motor Activity / Q000502:physiology; D016016:Proportional Hazards Models; D012307:Risk Factors; D011795:Surveys and Questionnaires; D013690:Television / Q000706:statistics & numerical data*; D014481:United States / Q000453:epidemiology; D016138:Walking / Q000502:physiology / Q000706:statistics & numerical data; D016387:Women's Health; D055815:Young Adult