After adjusting for covariates including age, male, hypertension, diabetes, congestive heart failure, cancer, RAS inhibitors, diuretics, body mass index, diastolic BP, white blood cells, hemoglobin, and serum levels of glucose, protein, albumin, cholesterol, bilirubin, and BUN, hyponatremia was independently associated with the increased risk of AKI development with HR 1.300 (95% CI, 1.086–1.555; P = 0.004) in multivariate Cox proportional hazard regression. This evidence concerns the gene ALB and acute kidney injury.