Role of anthropometric indexes and blood pressure as determinants of left ventricular mass and geometry in adolescents. The Rio de Janeiro Study.

Abstract

To evaluate left ventricular structural changes and their relationship to blood pressure and anthropometric indexes, we examined by echocardiography 108 adolescents aged 13 to 19 years. Subjects were divided into three groups according to blood pressure tracking during three moments of observation: group 1 (n = 27), > or = 95th percentile; group 2 (n = 37), < or = 50th percentile; and group 3 (n = 44), blood pressure not stable in the original percentile. Left ventricular mass index and the prevalence of altered left ventricular geometry were greater in group 1 (P < .05 and P < .02, respectively). Of all the anthropometric indexes, body surface area showed the best correlation with left ventricular mass (P < .00001). Left ventricular mass also correlated with systolic and diastolic pressures (P < .00001 and P < .003, respectively). Ventricular septal and posterior wall thicknesses and left ventricular diastolic diameter showed good correlations with body surface area (P < .00001). These variables also correlated with systolic pressure (P < .001). In a multiple regression model when body surface area was controlled, systolic pressure did not correlate significantly with left ventricular mass. In a similar model systolic pressure maintained a significant correlation with ventricular septal and posterior wall (P < .00001) thicknesses but not with left ventricular diastolic diameter (P > .05). We conclude that left ventricular structural changes can occur early after initial abnormalities of blood pressure. Considering that body surface area and systolic pressure were the best predictors of left ventricular alterations in adolescents, the usual way of correcting left ventricular mass by body surface area should be reviewed.