Background Renal injury is a common target organ damage associated with hypertension. Early identification and intervention can help delay or prevent the occurrence of end-stage renal disease. Previous studies have shown that aldosterone levels are independently associated with urinary microalbuminuria in patients with essential hypertension under complete drug washout conditions. However, the impact of aldosterone on renal injury in patients with essential hypertension—including those receiving angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin Ⅱ receptor antagonists (ARBs)—remains unclear.

Objective To explore the effect of aldosterone on renal injury in treated primary hypertension patients (including those taking ACEI or ARB).

Methods Patients with treated essential hypertension who were hospitalized in the Department of Hypertension, the Sixth Medical Center of PLA General Hospital from January 2021 to October 2024 were enrolled. According to their supine aldosterone levels, participants were stratified into quintiles using the following cutoffs, Q1 group (< 4.8 ng/dL), Q2 group (4.8 - 6.39 ng/dL), Q3 group (6.4 - 8.49 ng/dL), Q4 group (8.5 - 11.24 ng/dL), and Q5 group (≥11.25 ng/dL). Data including sex, age, body mass index, duration of hypertension, blood pressure, heart rate, fasting blood glucose, renal function, lipid profile, renin, aldosterone, 24 h urine protein, and 24 h urinary microalbumin were collected. Multivariate logistic regression analysis was used to evaluate the effect of aldosterone on renal injury in patients with essential hypertension.

Results A total of 895 patients with essential hypertension were enrolled, including 501 males (55.98%), with a mean age of (54.46 ± 14.51) years. The median plasma aldosterone level was 7.40 (IQR: 5.30 - 10.30) ng/dL. The renal injury rates progressively increased across aldosterone quartiles (Q1 - Q5: 31/177, 35/184, 29/173, 40/182, and 65/179, respectively; P < 0.05), exhibiting a positive correlation with aldosterone levels. Compared with patients in the Q1, Q2, Q3, and Q4 groups, patients in the Q5 group were younger, with higher systolic and diastolic blood pressures, faster heart rates, lower levels of blood potassium and chloride, lower proportion of coronary heart disease, and higher proportion of chronic renal insufficiency. Additionally, 24 h urine protein and 24 h urinary microalbumin levels were higher in the Q5 group. After adjusting for other confounding factors (age, gender, body mass index, systolic pressure, diastolic pressure, smoking history, drinking history, blood potassium, blood uric acid, total cholesterol, triglycerides, ACEI, ARB, calcium channel blockers, diabetes, and coronary heart disease), the risk of renal injury in the Q5 group was significantly higher than that in the Q1 groups (OR=2.571, 95% CI: 1.456 - 4.538, P=0.001). In the sensitivity analysis excluding patients receiving ACEI or ARB, the risk of renal injury in the Q5 group remained significantly higher than that Q1 group (OR=2.387, 95% CI: 1.139 - 5.004, P=0.021).

Conclusion Elevated plasma aldosterone levels are independently associated with renal injury in patients with essential hypertension. Higher aldosterone levels may contribute to hypertension-mediated renal injury, suggesting the potential value of aldosterone assessment for risk stratification.