The Association Between Salt Taste Threshold and Hypertensive Nephropathy in Patients With Essential Hypertension

Background To investigate the relationship between salt taste threshold and hypertensive nephropathy in patients with essential hypertension. Methods A cross-sectional study was conducted in 346 hypertensive patients in Daping Hospital from 2017 to 2019. Among them 94 patients were hypertensive nephropathy and 252 hypertensive patients without renal damage served as controls. The salt taste threshold of patients was measured by taking different concentrations of NaCl solution. The difference in salt taste threshold between the 2 groups of patients was compared, and the correlation between salt taste threshold and hypertensive nephropathy was analyzed. Receiver operating characteristic (ROC) curve was used to analyze the value of salt taste threshold to predict hypertensive nephropathy. Results The salt taste threshold of the hypertensive nephropathy patients was significantly higher than that in hypertensive patients without renal damage [0.075 (0.050–0.100) vs. 0.050 (0.050–0.100) mol/l, P = 0.010]. As salt taste threshold increased, the renal function decreased gradually, which was manifested by the increase of urine microalbumin to creatinine ratio, blood creatinine, blood urea nitrogen, urine N-acetyl-β-glucosaminidase, and the decrease of estimated glomerular filtration rate. Logistic regression analysis showed that after adjusting for traditional risk factors, a higher salt taste threshold was an independent risk factor for hypertensive nephropathy (odds ratio = 1.299, 95% confidence interval [CI] 1.020–1.655, P = 0.034). The area under ROC curve was 0.586 (95% CI 0.520–0.652). Conclusions Salt taste threshold correlates with biochemical indicators of renal damage, and a higher salt taste threshold is a risk factor of hypertensive nephropathy in patients with essential hypertension.