RELATIONSHIP OF CARDIOVASCULAR RISK-FACTORS TO ECHOCARDIOGRAPHIC LEFT-VENTRICULAR MASS IN HEALTHY-YOUNG BLACK-AND-WHITE ADULT MEN AND WOMEN- THE CARDIA STUDY

Background The objective of this study was to describe the distributio n of echo left ventricular (LV) mass and its association with demograp hic and cardiovascular risk factors in a large race- and sex-balanced cohort of young adults. Recent epidemiological data have suggested tha t M-mode echocardiographically determined LV hypertrophy is an indepen dent predictor of mortality and morbidity from coronary heart disease (CHD) in older adults. Echocardiographic LV mass has been associated i n middle-aged and older adults with multiple factors including age, ar terial blood pressure, body mass, and sex. However, there are few data describing the distribution of echo LV mass among black and white you ng adult men and women and relating LV mass to cardiovascular disease risk factors within race-sex subgroups. Methods and Results CARDIA (Co ronary Artery Risk Development in Young Adults) is a multicenter study of young adults, including approximately equal proportions of black a nd white men and women aged 23 to 35 years at the time of echo examina tion (1990 through 1991). Two-dimensionally guided M-mode echocardiogr ams were attempted in 4243 participants with recordings deemed accepta ble for calculation of LV mass, that is, of at least fair quality scor e, obtained in 3840 (90.5% of the 1990-1991 cohort). M-mode LV mass wa s calculated from the formula of Devereux and Reichek, adapted for use with measurements made according to the American Society of Echocardi ography Standards. LV mass was greater in men than in women and greate r in blacks than in whites (P<.001) (mean+/-SD): black men, 176+/-42 g ; white men, 169+/-40 g; black women, 135+/-38 g; and white women, 125 +/-33 g. In all race-sex groups, LV mass was positively correlated (P< .0001) in bivariate analyses with body weight, subscapular skinfold th ickness, height, and systolic blood pressure. In multivariate analyses , LV mass remained independently and positively related to body weight and systolic blood pressure and, when body weight was not considered, with subscapular skinfold thickness and height. In addition, the mult ivariate models allowed us to infer a direct relation between LV mass and both fatness and lean body mass. Weaker positive associations were noted of LV mass with pulse pressure in white participants and with p hysical activity in men. After adjustment for subscapular skinfold thi ckness, height, systolic and diastolic blood pressures, alcohol consum ption, pulmonary function, smoking history, physical activity, total s erum cholesterol, and family history of hypertension, LV mass remained higher in men than in women (P<.0001), in black men (167+/-43 g) than in white men (156+/-50 g, P<.0001), and in black women (142+/-49 g) t han in white women (137+/-43 g, P<.002). Conclusions In the healthy yo ung adults of the CARDIA cohort, LV mass was highly correlated with bo dy weight, subscapular skinfold thickness, height, and systolic blood pressure across race and sex subgroups. Furthermore, after adjustment for anthropometric, blood pressure, and other covariates, LV mass rema ined higher in men than in women and in blacks than in whites. Longitu dinal studies are necessary to delineate the possible roles of these f actors in the genesis of LV hypertrophy.