Influence of physical activity measurement on the association between Life's Essential 8 and incident cardiovascular disease in older women

Abstract

Objective: The American Heart Association's Life's Essential 8 (LE8) metric includes self-reported physical activity as one of the metrics for assessing cardiovascular health. Self-reported physical activity is prone to misclassification, whereas accelerometer measures are less biased. We examined associations of LE8 and incident cardiovascular disease (CVD) using self-reported and accelerometer-measured physical activity.

Methods: Participants in the Women's Health Initiative (WHI) Objective Physical Activity and Cardiovascular Health Study (n = 4,243; mean age = 79 ± 7 years) with no CVD history completed the WHI physical activity questionnaire and the Community Healthy Activities Model Program for Seniors (CHAMPS) questionnaire prior to wearing a hip-worn accelerometer for up to seven days in 2012-2014. LE8 components (physical activity, diet, sleep, body mass index, smoking, blood pressure, non-HDL cholesterol, and glucose) were scored according to guidelines. Scores were created using five physical activity measures: WHI questionnaire (LE8_WHI), CHAMPS (LE8_CHAMPS), accelerometer-measured physical activity (LE8_A), and sample quantiles of accelerometer-measured physical activity (LE8_AQ) and daily steps (LE8_STEPS). Hazard ratios (HR) for physician-adjudicated CVD were estimated using Cox regression.

Results: 707 incident CVD events occurred over an average 7.5 years. Multivariable HRs (95 % CI) comparing women in the highest vs. lowest quartiles of LE8 scores were: LE8_WHI = 0.53 (0.43-0.67), LE8_CHAMPS = 0.47 (0.38-0.60), LE8_A = 0.44 (0.36-0.56), LE8_AQ = 0.44 (0.35-0.55), and LE8_STEPS = 0.45 (0.35-0.57).

Conclusions: The LE8-incident CVD association varies by physical activity measurement, however all methods showed reduced risk. Device-measures of physical activity may be more accurate in the LE8, but when impractical to implement, also support use of self-reported measures.

Keywords: Accelerometer; Cardiovascular health; Device; Questionnaire; Steps; Women’s health.

Fig. 1

Dose-response associations of Life’s Essential 8 score and incident cardiovascular disease, by Life’s Essential 8 score separately and combined using restricted cubic spline models in the Women’s Health Initiative Objective Physical Activity and Cardiovascular Health Study in 40 United States clinical sites, 2012–2014. Abbreviations: LE8, Life’s Essential 8; LE8_A, Life’s Essential 8 score calculated using accelerometer-measured minutes per week of moderate-to-vigorous physical activity; LE8_AQ, Life’s Essential 8 score calculated using sample-based quantiles accelerometer-measured minutes per week of moderate-to-vigorous physical activity; LE8_CHAMPS, Life’s Essential 8 score calculated using the Community Healthy Activities Model Program for Seniors questionnaire; LE8_STEPS, Life’s Essential 8 score calculated using sample-based quantiles accelerometer-measured average steps per day; LE8_WHI, Life’s Essential 8 score calculated using the Women’s Health Initiative’s physical activity questionnaire. Models adjusted for age, race/ethnicity, education, alcohol use, and multimorbidity. Results were trimmed at the 1st and 99th percentiles. Associations were modeled using restricted cubic splines with knots placed at the 10th, 50th, and 90th percentiles, with the referent value placed at a score of 50. All associations were linear only (all p-non-linear > 0.50).