Relative impact of blood pressure as compared to an excess adiposity on left ventricular diastolic dysfunction in a community sample with a high prevalence of obesity
Cardiovascular Pathophysiology and Genomics Research Unit, School of Physiology, University of the Witwatersrand Medical School, 7 York Road, Parktown, Johannesburg, South Africa; Department of Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
Aim: To determine whether blood pressure (BP) or an excess adiposity, both frequently observed comorbidities that independently relate to left ventricular diastolic dysfunction (LVDD), have a greater impact on LVDD at a community level. Methods: We assessed the relative independent impact of an excess adiposity versus BP on indices of LVDD as determined from the ratios of early-to-late transmitral blood flow velocity (E/A) and E/the mean of lateral and septal wall myocardial tissue lengthening at the level of the mitral annulus (e'; (E/e') in 417 randomly recruited participants of a community-based study with a high prevalence of excess adiposity (43% obese and 25% morbidly obese). Results: In multivariate adjusted models, including adjustments for appropriate BP values (SBP for E/e' and DBP for E/A), waist circumference was independently associated with E/A (partial r = -0.12, P < 0.02) and E/e' (partial r = 0.15, P < 0.005). In contrast, BMI was independently associated with E/e' (partial r = 0.11, P < 0.05), but not E/A (partial r = -0.09, P = 0.08). In multivariate models, SBP had a greater impact on E/e' (standardized β-coefficient = 0.32 ± 0.05, P < 0.0001) than did waist circumference (standardized β-coefficient = 0.16-0.05, P < 0.005; P < 0.05 for comparison), whereas DBP had a similar impact on E/A (standardized β-coefficient = -0.10 ± 0.03, P < 0.005) as did waist circumference (standardized β-coefficient = -0.10 ± 0.04, P < 0.05). Importantly, whereas SBP was the main factor independently associated with an increased E/e' (≥10) (P < 0.0005), waist circumference was not independently associated with either a decreased E/A (≤0.75) (P = 0.82) or an increased E/e' (≥10; P = 0.15). Conclusion: In a community sample with a high prevalence of excess adiposity, BP exceeds obesity as the most important modifiable risk factor for LVDD. These data suggest that in communities with a high prevalence of obesity, if weight loss programmes fail to produce sustainable target body weights, rigorous BP management to lower than normal thresholds may be sufficient to prevent LVDD. Copyright © Lippincott Williams & Wilkins.
adult; Article; blood flow velocity; blood pressure measurement; body mass; community sample; comorbidity; controlled study; diastolic blood pressure; female; heart ventricle septum; human; left ventricular diastolic dysfunction; major clinical study; male; measurement accuracy; middle aged; model; morbid obesity; obesity; prevalence; priority journal; systolic blood pressure; waist circumference; waist hip ratio; blood pressure; community care; comparative study; diastole; echocardiography; echography; heart left ventricle function; morbid obesity; obesity; pathophysiology; South Africa; Adiposity; Blood Flow Velocity; Blood Pressure; Community Health Services; Diastole; Echocardiography; Female; Humans; Male; Middle Aged; Obesity, Morbid; South Africa; Ventricular Dysfunction, Left; Waist Circumference