Body composition and prevalence of left ventricular hypertrophy

Background-Fat-free mass (FFM) has been proposed as an optimal normalizatio n of left ventricular (LV) mass to body size. We sought to evaluate the nov el FFM-based criteria of LV hypertrophy (LVH). Methods and Results-A population sample of 1371 men and women aged 25 to 74 years was examined by echocardiography and bioelectrical impedance analysi s. Internal partition values for LVH were generated in a healthy population subgroup on the basis of LV mass divided by FFM and by the traditional ind exations to body height, height(2 7), and body surface area. In contrast to the sex-specific criteria required by traditional indexations, the value o f LV mass/FFM that divided individuals with and without LVH was identical f or men and women (4.1 g/kg). Estimates of LVH prevalence varied significant ly by type of indexation used, internally or externally derived cut points, and by population subgroups. Differences were pronounced among hypertensiv es and the obese. Thus, the application of LV mass/FFM more than halved the risk of LVH in obese versus nonobese women (odds ratio, 2.5; 95% confidenc e interval, 1.6 to 4.0) compared with criteria based on LV masskeight(2.7) (odds ratio, 5.5; 95% confidence interval, 3.6 to 8.3). Implications among hypertensives were less marked. Conclusions-Indexation of LV mass to FFM eliminates sex-specific LVH criter ia. The proportion of individuals defined as having LVH using the new crite ria deviate markedly from traditional indexations. Prospective investigatio ns will be needed to identify the prognostic implications of different inde xations, especially in subgroups such as the obese.