Hoehner C.M.,Washington University in St. Louis |
Barlow C.E.,Cooper Institute |
Allen P.,Washington University in St. Louis |
Schootman M.,Washington University in St. Louis
American Journal of Preventive Medicine | Year: 2012
Background: Limited evidence exists on the metabolic and cardiovascular risk correlates of commuting by vehicle, a habitual form of sedentary behavior. Purpose: To examine the association between commuting distance, physical activity, cardiorespiratory fitness (CRF), and metabolic risk indicators. Methods: This cross-sectional study included 4297 adults who had a comprehensive medical examination between 2000 and 2007 and geocoded home and work addresses in 12 Texas metropolitan counties. Commuting distance was measured along the road network. Outcome variables included weekly MET-minutes of self-reported physical activity, CRF, BMI, waist circumference, triglycerides, plasma glucose, high-density lipoprotein cholesterol, systolic and diastolic blood pressure, and continuously measured metabolic syndrome. Outcomes were also dichotomized using established cut-points. Linear and logistic regression models were adjusted for sociodemographic characteristics, smoking, alcohol intake, family history of diabetes, and history of high cholesterol, as well as BMI and weekly MET-minutes of physical activity and CRF (for BMI and metabolic risk models). Analyses were conducted in 2011. Results: Commuting distance was negatively associated with physical activity and CRF and positively associated with BMI, waist circumference, systolic and diastolic blood pressure, and continuous metabolic score in fully adjusted linear regression models. Logistic regression analyses yielded similar associations; however, of the models with metabolic risk indicators as outcomes, only the associations with elevated blood pressure remained significant after adjustment for physical activity and CRF. Conclusions: Commuting distance was adversely associated with physical activity, CRF, adiposity, and indicators of metabolic risk. © 2012 American Journal of Preventive Medicine.
Willis B.L.,Cooper Institute |
Ayers C.R.,University of Texas Southwestern Medical Center
Circulation | Year: 2012
Background-Family history of coronary heart disease (CHD) has been well studied as an independent risk factor for CHD events in the short term (<10 years). However, data are sparse on the association between family history and risk for CHD across long-term follow-up. Methods and Results-We included 49 255 men from the Cooper Center Longitudinal Study. Premature family history of CHD was defined as the presence of angina, myocardial infarction, angioplasty, or bypass surgery in a relative <50 years of age. Cause-specific mortality was obtained from the National Death Index. The association between premature family history and cardiovascular disease (CVD) or CHD death was compared across 3 unique follow-up periods (0-10, >10-20, and >20 years). Lifetime risk was estimated by use of a modified survival analytic technique adjusted for competing risk with non-CVD death as the competing event. After 811 708 person-years of follow-up, there were 919 CHD deaths and 1456 CVD deaths. After adjustment for traditional risk factors, premature family history was associated with CHD mortality >10 to 20 years (1.59; 95% confidence interval, 1.14-2.22) and >20 years (1.43; 95% confidence interval, 1.05-1.95) with wider confidence intervals at 0 to 10 years (1.32; 95% confidence interval, 0.76-2.31). Similar findings were observed for CVD mortality. Compared with men without a family history of coronary artery disease, premature family history was associated with an 50% higher lifetime risk for both CHD and CVD mortality (13.7% versus 8.9% and 21% versus 14.1%, respectively). Conclusion-Premature family history was associated with a persistent increase in both CHD and CVD mortality risk across long-term follow-up, resulting in significantly higher lifetime risk estimates. © 2012 American Heart Association, Inc.
Barlow C.E.,Cooper Institute
American Journal of Cardiology | Year: 2010
Lowering the voltage to 100 kV is an effective method of reducing the radiation of coronary computed tomographic angiography (CTA). It is unknown, however, whether one could use a 100-kV CTA protocol with overweight or obese patients. We, thus, evaluated the effect of increasing body mass index (BMI) on various image quality parameters of 100-kV CTA. We also compared the radiation dose and diagnostic accuracy of 100-kV CTA with CTA performed at 120 kV. Three different protocols were studied: 120 kV, retrospective; 100 kV, retrospective; and 100 kV, prospective. The image quality and radiation doses were analyzed for each protocol. The effect of increasing BMI was also examined. A worsening of the noise, contrast-to-noise, and signal-to-noise ratios occurred with increasing BMI and decreasing voltages. The radiation exposure was significantly lowered with the 100-kV protocol and with prospective gating. Despite this image degradation, however, diagnostic images were obtained with 100-kV CTA, even in overweight and many obese subjects. Of the 66 subjects referred for invasive angiography because of the findings from CTA, 55 were correctly characterized (overall positive predictive value [PPV] of 83.3%). This PPV remained reasonable, irrespective of the voltage, until a BMI of 35 kg/m 2 was reached (PPV for 100-kV protocol 90.0% [27 of 30]; PPV for a BMI of <25 kg/m2 but <30 kg/m2 84.4% [27 of 32]; and PPV for a BMI of <30 kg/m2 but <35 kg/m2 81.8% [18 of 22]). In conclusion, 100-kV coronary CTA is feasible in overweight and many obese subjects. © 2010 Elsevier Inc. All rights reserved.
Cooper K.H.,Cooper Institute
Research Quarterly for Exercise and Sport | Year: 2010
The passage of Senate Bill 530 in June 2007 increased visibility about the importance of health-related fitness in Texas. As a result of the mandate, more than 2.6 million 3rd- through 12th-grade students from all Texas counties were evaluated between January 1, 2008, and June 1, 2008, using a standardized test of health-related physical fitness (FTTNESSGRAM®). This number represented 84.8% of all public school districts in Texas. In the subsequent 2 years, 2.8 and 2.9 million children were tested, which represents more than 90% of all public school districts in Texas. This summary provides reflections on the test results and implications for future school-based fitness initiatives, both in Texas and in other states. © 2010 by the American Alliance for Health, Physical Education, Recreation and Dance.
Farrell S.W.,Cooper Institute |
McAuley P.A.,Winston-Salem State University |
Barlow C.E.,Cooper Institute
Medicine and Science in Sports and Exercise | Year: 2010
Purpose: To determine the prospective associations among cardiorespiratory fitness (CRF), different measures of adiposity, and all-cause mortality in women. Methods: A total of 11,335 women completed a comprehensive baseline examination between 1970 and 2005. Clinical measures included body mass index (BMI), waist circumference (WC), waist-to-height ratio (W/HT), waist-to-hip ratio (W/Hip), percent body fat (%BF), and CRF quantified as duration of a maximal exercise test. Participants were classified by CRF as low (lowest 20%), moderate (middle 40%), and high (highest 40%) as well as by standard clinical cut points for adiposity measures. Hazard ratios (HR) were computed using Cox regression analysis. Results: During a mean follow-up of 12.3 ± 8.2 yr, 292 deaths occurred. HR for all-cause mortality were 1.0, 0.60, and 0.54 for low, moderate, and high fit groups, respectively (P for trend <0.01). Adjusted death rates of overweight/obese women within each adiposity exposure were somewhat higher compared with normal-weight women and approached statistical significance for BMI, %BF, and W/HT (P = 0.08, P = 0.08, and P = 0.07, respectively). When grouped for joint analyses into categories of fit and unfit (upper 80% and lower 20% of CRF distribution, respectively), HR were significantly higher in unfit women within each stratum of BMI compared with fit-normal BMI women. Fit women with high %BF (HR = 1.0), high WC (HR = 0.9), and high W/HT (HR = 1.2) had no greater risk of death compared with fit-normal-weight women (referent). Conclusions: Low CRF in women was a significant independent predictor of all-cause mortality. Higher CRF was associated with lower mortality within each category of each adiposity exposure. Using adiposity measures as predictors of all-cause mortality in women may be misleading unless CRF is also considered. Copyright © 2010 by the American College of Sports Medicine.