The application of early renal injury markers in the detection of hypertensive kidney lesions in the elderly

Objective: To investigate the application value of early renal injury markers in the detection of hypertensive kidney lesions in the elderly. Methods: 280 elderly patients (over 60 years old) with hypertension treated at the medical examination center in our hospital during the period from January 2016 to June 2017 were selected by random inspection as the hypertension group, and 200 healthy people receiving physical examinations in the hospital during the same time period were selected as the control group. After admission, levels of serum creatinine (Scr), Cystatin C (CysC), β₂-microglobulin (β₂-MG), blood urea nitrogen (BUN), retinol binding protein (RBP) and urinary microalbumin (UmALB) in two groups were determined. Renal function indexes were compared among elderly hypertensive patients, normal healthy subjects and patients with different grades of hypertension, and the glomerular filtration rate (GFR) was determined. According to the occurrence of renal function injury, the subjects were divided into the normal renal function group and the renal function injury group, a nd renal function indexes were compared between the two groups. The correlation between the GFR level of hypertension and renal injury markers was analyzed. Results: Levels of CysC, β₂-MG, RBP and UmALB in the hypertension group were higher than those in the control group (P < 0.05). Levels of CysC, β₂-MG, RBP and UmALB in patients with grade 2 and grade 3 hypertension were higher than those in patients with grade 1 hypertension. Levels of Scr, CysC, β₂-MG, BUN, RBP and UmALB in patients with grade 3 hypertension were higher than those in patients with grade 2 hypertension (P < 0.05). The detection rates of abnormal CysC, β₂-MG, RBP and UmALB in patients with grade 3 hypertension were higher than those in patients with grade 1 or grade 2 hypertension (P < 0.05), and the detection rates of abnormal CysC, RBP and UmALB in patients with grade 2 hypertension were higher than those in patients with grade 1 hypertension (P < 0.05). Levels of CysC, β₂-MG, RBP and UmALB in patients with renal function injury were higher than those in normal renal function group (P < 0.05). CysC, β₂-MG, RBP and UmALB were negatively correlated with GFR in hypertensive patients (P < 0.05). In terms of single detection, the detection rate of early renal damage in elderly patients with hypertension by β₂-MG was the highest, followed by RBP. The positive rate of single detection was lower than that of combined detection of early renal damage markers. Conclusion: CysC, β₂-MG, RBP and UmALB are up-regulated obviously in elderly patients with hypertension. With the aggravation of hypertension, the up-regulation of above-mentioned factors is more obvious, and changes of the expression was obviously negatively correlated GFR. (authors)