Correlation between Left Atrial Diameter and Renal Outcomes in Chronic Kidney Disease Patients

Abstract

BACKGROUND: An enlarged left atrium is frequently noted in chronic kidney disease (CKD) patients, and left atrial enlargement has been documented to be an independent predictor of adverse cardiovascular outcomes in CKD patients. However, little is known about the relation between left atrial diameter (LAD) and renal outcomes in this kind of patient. We assessed whether LAD was independently associated with renal function progression in patients with CKD stages 3-5.METHODS: This study is a prospective cohort study. We enrolled 398 patients, who were classified into three groups according to the degrees of LAD. The change in renal function was measured by the estimated glomerular filtration rate (eGFR) slope. Rapid renal progression was defined as an eGFR slope of 3 mL/min/1.73 m^2/year decrease or more. The renal end point was defined as commencement of dialysis. Multiple forward linear regression analysis was used to identify the factors associated with LAD. The associations between the tertile of LAD and the eGFR slope and rapid renal progression and progression to dialysis were assessed by a modified stepwise procedure in 3 modeling steps.RESULTS: Increased LAD was significantly associated with hypertension, obesity, high left ventricular mass index, low left ventricular ejection fraction, and high transmitral E wave velocity to early diastole mitral velocity ratio. Further, the highest tertile of LAD (vs. lowest tertile of LAD) was independently associated with eGFR slope (β = -0.155, P = 0.005) and rapid renal progression (odds ratio, 2.115; 95% confidence interval, 1.019 to 4.389; P = 0.044), but not to risks for progression to dialysis after adjustment of demographic, clinical, and biochemical parameters.CONCLUSION: Our findings show increased LAD is independently associated with a faster rate of renal function decline and rapid renal progression, but not with dialysis in CKD patients. Assessment of LAD by echocardiography might be useful to predict the risk of adverse renal outcomes.