Medicine & Science in Sports & Exercise:
F-25 Free Communication/Poster - Epidemiology - Diabetes, Obesity, Metabolism, CVD: JUNE 3, 2011 1:00 PM - 6:00 PM: ROOM: Hall B
Jackson, Andrew S. FACSM1; Lee, Duck-Chul2; Sui, Xuemei2; Church, Timothy S.3; O'Connor, Daniel P.1; Blair, Steven N. FACSM2
1University of Houston, Houston, TX. 2University of South Carolina, Columbia, SC. 3Pennington Biomedical Research Center, Baton Rouge, LA.
(No relationships reported)
Findings from prospective studies show that elevated fasting plasma glucose (FPG) is linked to variation in body composition (BC) and cardiorespiratory fitness (CRF). Higher FPG levels increase the risk of impaired fasting glucose, a strong predictor of type 2 diabetes.
PURPOSE: To define the independent association of BC and CRF on longitudinal changes with aging in FPG.
METHODS: The sample studied was 7266 men with an average of 5.3 tests between 1975 and 2006 for a total of 38383 observations. The men were from the Aerobics Center Longitudinal Study and ranged in age from 20 to 96 y. CRF was measured with a maximal Balke exercise test and BC was assessed by percent body fat (%BF) and BMI.
RESULTS: Linear mixed models regression (LMM) showed that FPG increased with aging at a non-linear rate. Adding BC, CRF and the interaction of age and CRF to the LMM significantly improved fit over aging alone. Using BMI or %BF to sample BC produced equivalent results. The model showed that FPG increased with aging and adiposity. A graphic examination of the CRF by age interaction found that CRF was associated with longitudinal changes in FPG. Examination of the FPG change trajectories showed that the relation between CRF and FPG was negative and that the CRF effect increased with aging after age 40 y.
CONCLUSIONS: Aging, BC and CRF are independent determinants of longitudinal changes in FPG. The statistical models showed that FPG increases with aging and adiposity. The inverse effect of CRF on longitudinal changes in FPG is age-related, after age 40 y the CRF effect increases with aging.
Supported by NIH Grants AG06945, HL62508, and R21DK088195, and an unrestricted research grant from the Coca-Cola Company.