Physical activity and television viewing in relation to risk of undiagnosed abnormal glucose metabolism in adults.
OBJECTIVE
The goal of this study was to assess the associations of physical activity time and television (TV) time with risk of "undiagnosed" abnormal glucose metabolism in Australian adults.


METHODS
This population-based cross-sectional study using a stratified cluster design involving 42 randomly selected Census Collector Districts across Australia included 8,299 adults aged 25 years or older who were free from new type 2 diabetes and self-reported ischemic disease and did not take lipid-lowering or antihypertensive drugs. Abnormal glucose metabolism (impaired fasting glycemia [IFG], impaired glucose tolerance [IGT], or new type 2 diabetes) was based on an oral glucose tolerance test. Self-reported physical activity time and TV time (previous week) were assessed using interviewer-administered questionnaires.


RESULTS
After adjustment for known confounders and TV time, the odds ratio (OR) of having abnormal glucose metabolism was 0.62 (95% CI 0.41-0.96) in men and 0.71 (0.50-1.00) in women for those engaged in physical activity >or=2.5 h/week compared with those who were sedentary (0 h/week). The ORs of having abnormal glucose metabolism were 1.16 (0.79-1.70) in men and 1.49 (1.12-1.99) in women who watched TV >14 h/week compared with those who watched <or=7.0 h/week. Higher TV viewing (>14 h/week) was also associated with an increased risk of new type 2 diabetes in men and women and IGT in women compared with those watching <14 h/week. Total physical activity of >or=2.5 h/week was associated with a reduced risk of IFG, IGT, and new type 2 diabetes in both sexes; however, only the association with IGT in women was statistically significant.


CONCLUSIONS
These findings suggest a protective effect of physical activity and a deleterious effect of TV time on the risk of abnormal glucose metabolism in adults. Population strategies to reduce risk of abnormal glucose metabolism should focus on reducing sedentary behaviors such as TV time, as well as increasing physical activity.
Dunstan
David W
DW
International Diabetes Institute, Melbourne, Australia 3162. ddunstan@idi.org.au
Salmon
Jo
J
Owen
Neville
N
Armstrong
Timothy
T
Zimmet
Paul Z
PZ
Welborn
Timothy A
TA
Cameron
Adrian J
AJ
Dwyer
Terence
T
Jolley
Damien
D
Shaw
Jonathan E
JE
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000209:etiology* / Q000517:prevention & control; D005215:Fasting / Q000097:blood; D005260:Female; D018149:Glucose Intolerance / Q000209:etiology* / Q000517:prevention & control; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D016017:Odds Ratio; D012307:Risk Factors; D011795:Surveys and Questionnaires; D013690:Television; D013997:Time Factors
D001786:Blood Glucose