title: Contribution of central and general adiposity to abnormal left ventricular diastolic function in a community sample with a high prevalence of obesity.
abstract: The relative independent contribution of excess adiposity, as indexed by measures of central, general, or peripheral adiposity, toward abnormal cardiac diastolic chamber function at a community level is unclear. In 377 randomly selected participants >16 years old from a community sample with a high prevalence of excess adiposity ( approximately 25% overweight and approximately 43% obese), we assessed the independent contribution of the indexes of adiposity to the variation in early-to-late (atrial) transmitral velocity (E/A). After adjustments for a number of confounders, including age, gender, pulse rate, conventional diastolic (or systolic) blood pressure, antihypertensive treatment, left ventricular mass index, and the presence of diabetes mellitus or a hemoglobin A1c level >6.1%; waist circumference was an independent predictor of a reduced E/A (p = 0.0038). Body mass index (p = 0.07), waist-to-hip ratio (p = 0.23), and skinfold thickness (p = 0.37) were not independently associated with E/A, whereas waist circumference was independently associated with E/A, even after adjustments for other adiposity indexes, including body mass index (p <0.05 to 0.005). In contrast to the effects on diastolic function, the waist circumference did not correlate with the left ventricular ejection fraction (p = 0.23). The independent relation between the waist circumference and E/A (standardized beta coefficient -0.14 +/- 0.05, p = 0.0038) was second only to age (standardized beta coefficient -0.57 +/- 0.05, p <0.0001) and similar to blood pressure (standardized beta coefficient -0.11 +/- 0.04, p = 0.0075) in the magnitude of the independent effect on E/A. The inclusion of the relative wall thickness rather than the left ventricular mass index in the regression equation produced similar outcomes. The exclusion of the left ventricular mass index and relative wall thickness from the regression equations or the inclusion of carotid-femoral pulse wave velocity or 24-hour blood pressure as confounders failed to modify the relation between waist circumference and E/A. In conclusion, the waist circumference was second only to age in the impact on an independent association with E/A in a population sample with a high prevalence of excess adiposity. This effect was not accounted for by left ventricular hypertrophy or remodeling, the 24-hour blood pressure, or arterial stiffness.
authors.affiliation: Cardiovascular Pathophysiology and Genomics Research Unit, University of the Witwatersrand Faculty of Health Sciences School of Physiology, Johannesburg, South Africa.
authors.forename: Carlos D
authors.initials: CD
authors.lastname: Libhaber
authors.forename: Gavin R
authors.initials: GR
authors.lastname: Norton
authors.forename: Olebogeng H I
authors.initials: OH
authors.lastname: Majane
authors.forename: Elena
authors.initials: E
authors.lastname: Libhaber
authors.forename: Mohammed R
authors.initials: MR
authors.lastname: Essop
authors.forename: Richard
authors.initials: R
authors.lastname: Brooksbank
authors.forename: Muzi
authors.initials: M
authors.lastname: Maseko
authors.forename: Angela J
authors.initials: AJ
authors.lastname: Woodiwiss
mesh_terms: D050153:Abdominal Fat / Q000503:physiopathology*; D050154:Adiposity; D000328:Adult; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000209:etiology; D003971:Diastole; D005260:Female; D006801:Humans; D006973:Hypertension / Q000209:etiology; D017379:Hypertrophy, Left Ventricular / Q000209:etiology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications* / Q000453:epidemiology*; D050177:Overweight / Q000150:complications / Q000453:epidemiology; D011237:Predictive Value of Tests; D015995:Prevalence; D012494:Sampling Studies; D012885:Skinfold Thickness; D013019:South Africa / Q000453:epidemiology; D018487:Ventricular Dysfunction, Left / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology*; D055105:Waist Circumference; D049629:Waist-Hip Ratio