For example, some studies defined early dialysis in terms of GFR levels, while other studies are defined by a comprehensive determination of laboratory indicators (such as hemoglobin, serum albumin, blood urea nitrogen, serum creatinine, potassium, phosphorus, and so on) and/or clinical symptoms (including acute heart failure, pulmo-nary edema or hypertension that was difficult to control with medication). This evidence concerns the gene ALB and hypertensive disorder.