<scp>A</scp>merican <scp>H</scp>eart <scp>A</scp>ssociation's <scp>L</scp>ife's <scp>S</scp>imple 7 and incidence of venous thromboembolism
Authors: Aaron R. Folsom, Nels C. Olson, Pamela L. Lutsey, Nicholas S. Roetker, Mary Cushman
Journal: American Journal of Hematology (2015)

The American Heart Association (AHA) has recently promoted primary prevention of cardiovascular disease (CVD) by recommending that Americans optimize "Life's Simple 7." As described in Supporting Information Table 1, Life's Simple 7 comprises seven CVD risk factors or behaviors (smoking, body mass index, physical activity, diet, total cholesterol, blood pressure, and fasting serum glucose), which AHA categorized into ideal, intermediate, or poor levels 1. The Atherosclerosis Risk in Communities (ARIC) Study reported that the number of ideal levels achieved is associated strongly and inversely with subsequent incidence of arterial CVD and cancer 2, 3. Although some of Life's Simple 7 components (e.g., high BMI) are known to increase the risk of venous thromboembolism (VTE), only one previous study has suggested that greater adherence to Life's Simple 7 can reduce VTE 4. We sought to verify whether Life's Simple 7 relates to VTE (venous thrombosis and pulmonary embolism) incidence. The ARIC Study 5 enrolled 15,792 men and women aged 45–64 years in 1987–1989, and conducted four subsequent examinations and annual telephone contact. For this analysis, we excluded those who were: not white or African American (n = 48), had a prior VTE (n = 276), were taking anticoagulants (n = 73), were not fasting for 8 hr (n = 503), had missing dietary data or had implausible energy intake (n = 336), or had incomplete information on other Life's Simple 7 components (n = 458), which left 14,098 participants (n = 10,617 whites and 3,481 African Americans). At baseline, ARIC measured risk factors within its cohort and classified each risk factor according to AHA's Simple 7 categories of ideal, intermediate, or poor (Supporting Information Table 1) 1, 2. For analysis, we further categorized adherence with Life's Simple 7 in two ways. Firstly, we simply counted the number of ideal Life's Simple 7 components that each participant met. Secondly, as done previously 4, we created a score in which each component was given points of 0, 1, or 2 to represent poor, intermediate, or ideal health categories, respectively, and these were summed to yield a Life's Simple 7 score. This score was categorized as inadequate (0–4), average (5–9), or optimal (10–14) for cardiovascular health. ARIC contacted participants annually by phone and asked about all hospitalizations in the previous year. To validate the VTE events, two physicians (ARF, MC) reviewed the hospital records using standardized criteria 6. A diagnosis of deep vein thrombosis or pulmonary embolus required positive imaging tests. For this analysis, we restricted deep vein thromboses to those occurring in the lower extremity or vena cava. Among the 14,098 ARIC participants aged 45–64, who were followed a median of 22.5 years, 629 incident VTEs were identified. As shown in Table 1, ARIC participants having ≥4 ideal components of Life's Simple 7 at baseline had approximately half the VTE incidence of those with fewer ideal health components. As shown in Fig. 1, the Life's Simple 7 score (range 0–14, giving 2 points for ideal, 1 point for intermediate, and 0 points for poor components) was likewise associated inversely with VTE incidence. The age, sex, and race adjusted hazard ratios (95% CI) of VTE were: 1.0 (reference) for a Life's Simple 7 score of 0–4 (inadequate), 0.77 (0.59, 1.01) for a score of 5–9 (average), and 0.44 (0.32, 0.61) for a score of 10–14 (optimal). Better BMI, physical activity, and blood pressure components individually contributed the most to the reduced VTE risk associated with Life's Simple 7 adherence. Cumulative incidence of venous thromboembolism (VTE) in relation to three categories of a Life's Simple 7 Score, ARIC, 1987–2011. Limitations of this study include the inability to capture VTE events treated only in the outpatient setting; yet several pilot studies in ARIC have suggested that the vast majority of initial VTEs during 1987–2011 were hospitalized. We also examined Life's Simple 7 at only a single time-point, but did so because we were interested in the potential impact of middle-age risk factors on subsequent VTE events. In conclusion, this prospective study confirmed that greater adherence to ideal levels of AHA's Life's Simple 7 in middle age is associated with reduced risk of VTE later in life. This is important because Life's Simple 7 guidelines were developed to prevent arterial CVD, not VTE, and because there are few strategies to prevent VTE other than prophylactic anticoagulation. Our findings and those from REGARDS 4 suggest that, if widely adopted by middle-age, adherence to Life's Simple 7 may reduce the public health burden of VTE. Aaron R. Folsom,1* Nels C. Olson,2 Pamela L. Lutsey,1 Nicholas S. Roetker,1Mary Cushman3,4 1Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, Minnesota; 2Department of Pathology, University of Vermont, Burlington, Vermont; 3Department of Medicine, University of Vermont, Burlington, Vermont; 4Department of Pathology, University of Vermont, Burlington, Vermont Additional Supporting Information may be found in the online version of this article. Supporting Information Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.