Relationship between objectively measured physical activity and cardiovascular aging in the general population--the EVIDENT trial.

BACKGROUND: Aging has been associated with an increase in arterial stiffness. We analyzed the relationship between regular physical activity and cardiovascular aging evaluated by the radial augmentation index (rAIx), ambulatory arterial stiffness index (AASI), pulse pressure (PP) and heart age in subjects without atherosclerotic disease. METHODS: A cross-sectional study was performed including 1365 subjects from the EVIDENT trial (mean age 54.9±13.7 years; 60.3% women). As a measure of total volume of physical activity we used counts/minute recorded in an accelerometer (Actigraph GT3X) that participants wore for seven days, collecting data in 60-sec epochs, and respondents with ≥4 valid days were retained for the analysis. Arterial stiffness was evaluated using measures of rAIx, AASI, and central and peripheral PP on the B-pro device. rAIx was adjusted to 75 heart rate(rAIx75). Cardiovascular risk and heart age was estimated by the Framingham Risk Score. RESULTS: The median (IQR) of counts/min was 236.9 (176.3-307.8), rAIx75 90 (77-100), sleep PP 40 mmHg (33-47), central PP 39 mmHg (32-47) and heart age 57 years (45-73) and the mean±SD of the ASSI was 0.44±0.07. We found an inverse correlation between counts/minute and rAIx75 (r=-0.086; p<0.01), AASI (r=-0.146; p<0.001), heart age (r=-0.163; p<0.001) and peripherals PP. These associations were remained after controlling for potential confounders, except for rAIx75. In the multiple regression analysis, after adjustment, an inverse association persisted between counts/minute and AASI, sleep PP and heart age, but not with rAIx75. Accordingly, for every 100 higher counts/minute of accelerometer measures, both AASI and sleep PP would be lower by one measurement unit (beta=-0.979 and -1.031 respectively, p<0.001) and the estimated heart age by half year (beta=-0.525, p=0.023). CONCLUSIONS: Regular physical activity was inversely associated with parameters related to advanced cardiovascular aging after adjustment for potentially influencing variables. TRIAL REGISTRATION: Clinical Trials.gov Identifier: NCT01083082.

Confirmatory factor analysis to assess the measure of adiposity that best fits the diagnosis of metabolic syndrome and relationship to physical activity in adults.

PURPOSE: The objective of the study is to assess the goodness of fit for the diagnosis of metabolic syndrome in adults of four models with different measures of adiposity using confirmatory factor analysis, to develop a cardio metabolic risk index and to analyze its relationship to physical activity. METHODS: Cross-sectional descriptive multicenter study including 636 patients from the EVIDENT study. Considering as fixed variables, triglycerides/HDL-C ratio, HOMA-IR index and mean arterial pressure, we will compare which single-factor model of metabolic syndrome shows better goodness of fit. The models only differ by the measure of adiposity used: waist circumference, waist circumference/height, body mass index or adiposity index. With the factorial weights obtained, we created a quantitative metabolic index and analyzed its relationship to physical activity, quantified with the accelerometer for 1 week and measured at counts/min. RESULTS: The single-factor model including waist circumference in women and body mass index in men were those that were better indicators of goodness of fit. The estimated quantitative metabolic index shows a mean value in men of -0.022 ± 1.29 with a range of values between -3.36 and 4.57 and in women of 0.0001 ± 1.53 with a range of values between -3.17 and 5.55. The quantitative index shows an inverse relationship to physical activity. CONCLUSIONS: Waist circumference in women and body mass index in men are the measures of adiposity that were better indicators goodness of fit. This quantitative index may be useful to quantify the risk of metabolic syndrome in clinical practice.