Left atrial enlargement (LAE) reflects diastolic dysfunction and predicts mortality in end-stage renal disease patients. However, little is known of its prevalence and factors associated with subclinical LAE in earlier stages of chronic kidney disease (CKD).Methods
We conducted a prospective, cross-sectional study in 261 Stage 3–5 non-dialysis CKD patients without symptomatic cardiovascular disease with two-dimensional echocardiography performed to estimate left atrial volume index and other cardiac parameters.Results
One hundred and nine (41.8%) patients had LAE. Mild and moderate/severe LAEs were observed in 22.9 and 41.3% of patients with left ventricular (LV) hypertrophy (n = 109) versus 13.2 and 12.5% of patients with no LV hypertrophy (n = 152), respectively (P < 0.001). On univariate analysis, plasma sodium concentration showed a significant association with LAE [odds ratio (OR) 1.22, 95% confidence interval (95% CI) 1.09–1.37; P = 0.001]. In the stepwise multiple logistic regression, plasma sodium concentration emerged as one of the most significant factors associated with LAE (adjusted OR 1.29, 95% CI 1.14–1.47; P < 0.001]. Its significance was well maintained (adjusted OR 1.23, 95% CI 1.07–1.43; P = 0.005) when including LV mass and volume index and N-terminal pro-brain natriuretic peptide in the model, while blood haemoglobin and systolic blood pressure were displaced.Conclusions
This study for the first time alerted to a very high prevalence of subclinical LAE and reported a strong novel, independent relationship between plasma sodium concentration and subclinical LAE in Stage 3–5 CKD patients. Longitudinal studies are needed to establish causality between high plasma sodium concentration and LAE and their usefulness as therapeutic targets in CKD.