Indexation of left ventricular mass to predict adverse clinical outcomes in pre-dialysis patients with chronic kidney disease: KoreaN cohort study of the outcome in patients with chronic kidney disease

BACKGROUND: No study has compared the clinical impact of indexation of left ventricular mass (LVM) on adverse clinical outcomes in pre-dialysis patients with chronic kidney disease (CKD). METHODS: We reviewed 2,101 patients from a large-scale multi-center prospective study that gathered anthropometric and echocardiographic measurements and clinical outcomes. The LVM was indexed as body surface area (LVMI-BSA) and height raised to the power of 2.7 (LVMI-H2.7). The main outcomes were composite renal and cardiovascular events and all-cause mortality. Left ventricular hypertrophy (LVH) was defined as the highest sex-specific quartile of LVMI-BSA or LVMI-H2.7. RESULTS: During a mean period of 3.5 years, 692 patients developed composite outcomes (32.9%). The area under the curve at 5 year of LVM (60.6%) for composite outcome was smaller than that for LVMI-BSA (63.2%, P <0.001) and LVMI-H2.7 (63.4%, P <0.001). The hazard ratio (HR) and 95% confidence interval (CI) per one unit increase in LVM (g), LVMI-BSA (g/m(2)), and LVMI-H2.7 (g/m(2.7)) for composite outcomes were 1.004 (1.002–1.005, P <0.001), 1.011 (1.006–1.016, P <0.001), and 1.023 (1.012–1.035, P <0.001), respectively. Patients with LVH determined by LVMI-BSA and LVMI-H2.7 (HR 1.352, 95% CI 1.123–1.626, P = 0.001) and LVH determined by only LVMI-BSA (HR 1.908, 95% CI 1.233–2.953, P = 0.004) showed an independent increase in the risk of composite-outcome development, when compared with patients without LVH, according to LVMI-BSA and LVMI-H2.7. CONCLUSION: Indexation of LVM improved the prediction of adverse outcomes. BSA may be as useful as height(2.7) in indexing of LVM for predicting adverse outcomes in pre-dialysis patients with CKD.