Diastolic dysfunction and its association to renal outcomes in patients with chronic kidney disease

Abstract

Abstract Background Left ventricular diastolic dysfunction is frequent in chronic kidney disease (CKD) and is suspected to be linked to a worse renal prognosis. Purpose To investigate the association between the ratio of early mitral inflow velocity to early diastolic tissue velocity (E/e') measured by Doppler echocardiography and development of end-stage kidney disease in patients with non-dialysis-dependent CKD. Methods This prospective cohort study included individuals with non-dialysis-dependent CKD with previous nephrology-related hospital contact. All participants underwent thorough, protocolized echocardiographic examination. Exclusion criteria were inadequate image quality for E/e'-assessment and prevalent heart failure at baseline. The primary endpoint was the composite outcome of time to dialysis treatment and/or kidney transplantation. The association between E/e' and the composite outcome was assessed with multivariable Cox proportional hazards regression models adjusted for age, sex, estimated glomerular filtration rate (eGFR), diabetes, Body Mass Index, albuminuria, systolic blood pressure, heart rate, coronary artery disease, and left ventricular ejection fraction. Results A total of 731 participants were included in the final study sample. Mean age was 57 ± 13 years and 61% were male. Median E/e' was 7.8 (IQR: 6.4; 9.5), median eGFR was 43 mL/min/1.73 m² (IQR: 28; 62), and 36% had a urine albumin/creatinine ratio >300. During a median follow-up of 3.8 years (IQR: 3.3; 4.5), 102 individuals met the composite outcome. In univariable Cox regression both continuous E/e' and elevated E/e' (E/e' >14) were significantly associated with the outcome (P<0.001). Following multivariable adjustments, increasing E/e' remained significantly associated with the outcome (HR = 1.09, 95% CI [1.03; 1.15], P=0.004, per 1 unit increase) (Figure 1A). Elevated E/e' also remained significantly associated with the outcome following adjustments (HR = 2.95, 95% CI [1.33; 6.53], P=0.008), and more than 40% of patients with E/e' >14 were estimated to have reached the primary endpoint after 4 years (Figure 1B). Conclusion In patients with non-dialysis dependent CKD increasing E/e' and E/e' >14 were both associated with worse renal prognosis.