Differences in echocardiographic findings and systemic hemodynamics among non-diabetic American Indians in different regions: The Strong Heart Study

PURPOSE: This study was undertaken to determine whether differences in left ventricular (LV) and systemic hemodynamic findings exist between American Indians in different regions that might contribute to known differences in cardiovascular morbidity rates among American Indians. METHODS: We compared echocardiography results in 290 non-diabetic Strong He art Study (SHS) participants in Arizona, 595 in Oklahoma and 572 in North/S outh Dakota (ND/SD). RESULTS: Participants in the 3 regions were similar in age and gender but t hose in Arizona had the highest body mass indices and lowest heart rates wh ile those in ND/SD had the lowest diastolic blood pressures (BP). In analys es that adjusted for significant covariates, ND/SD participants had larger aortic (Ao) anular, Ao root, and LV chamber size as well as higher cardiac output and lower peripheral resistance, whereas Arizona participants had in creased LV wall thickness and mass and reduced LV myocardial contractility. These findings may contribute to the known high rates of cardiovascular ev ents in ND/SD Indians and to the proportionately higher rate of cardiovascu lar death than of non-fatal cardiovascular events that has been recently do cumented in Arizona Indians. CONCLUSIONS: Application of echocardiography to non-diabetic SHS participan ts reveals that LV chamber and arterial size are larger in ND/SD Indians an d that LV wall thicknesses and mass are higher and LV myocardial contractil ity lower in Arizona Indians, possibly contributing to the higher than expe cted rates of cardiovascular morbidity and mortality among Indians in Arizo na. Ann Epidemiol 2000;10:324-332. Published by Elsevier Science Inc.