Low renin hypertension (LRH) is a common condition in hypertensive patients, and mainly includes primary aldosteronism (PA) and low renin essential hypertension. To investigate the distributions and clinical manifestations of the main LRH forms, we reviewed 1267 hypertensive patients who underwent assessment for plasma renin activity (PRA) and plasma aldosterone concentration (PAC) by standardized protocols in our specialized center. LRH was defined as PRA < 1.0 ng/mL/h. A saline infusion test (SIT) was performed when LRH patients showed positive screening results for PA. The main LRH forms were defined as follows: post-SIT PAC > 10 ng/dL as ‘overt PA’, post-SIT PAC 5–10 ng/dL as ‘mild PA’, and post-SIT PAC < 5 ng/dL or negative screening results as ‘non-PA’. Overall, 760 patients were defined as LRH, with 160 classified as overt PA, 268 as mild PA, and 332 as non-PA. The total proportion of PA amounted to 56.3% with 21.0% overt PA and 35.3% mild PA. Compared with the mild PA, patients with overt PA had higher systolic and diastolic blood pressures, lower serum potassium, higher urine potassium excretion, more frequent incidence of stage 3 hypertension, hypokalemia, diabetes mellitus, and classical unilateral adenoma on computerized tomography (P < 0.05). PA including overt and mild forms is indeed a major form of LRH. Clinical manifestations in mild PA are less severe than those in overt PA. Nevertheless, mild PA is more prevalent than overt PA in LRH and should be recognized.

低肾素高血压（LRH）是高血压患者的常见病症，主要包括原发性醛固酮增多症（PA）和低肾素原发性高血压。为了研究主要 LRH 形式的分布和临床表现，我们回顾了 1267 名高血压患者，这些患者在我们的专业中心通过标准化方案接受了血浆肾素活性 (PRA) 和血浆醛固酮浓度 (PAC) 评估。LRH 定义为 PRA < 1.0 ng/mL/h。当 LRH 患者的 PA 筛查结果呈阳性时，进行盐水输注试验 (SIT)。主要的 LRH 形式定义如下：SIT 后 PAC > 10 ng/dL 为“明显 PA”，SIT 后 PAC 5–10 ng/dL 为“轻度 PA”，SIT 后 PAC < 5 ng/dL或阴性筛查结果为“非 PA”。总体而言，760 名患者被定义为 LRH，160 名患者被归类为明显 PA，268 为轻度 PA，332 为非 PA。PA 的总比例为 56.3%，其中显性 PA 占 21.0%，轻度 PA 占 35.3%。与轻度 PA 相比，明显 PA 患者的收缩压和舒张压更高，血清钾含量更低，尿钾排泄量更高，3 期高血压、低钾血症、糖尿病和计算机断层扫描显示的经典单侧腺瘤的发生率更高。P  < 0.05)。PA 包括显性和轻度形式确实是 LRH 的主要形式。轻度 PA 的临床表现不如明显 PA 严重。然而，在 LRH 中，轻度 PA 比明显 PA 更普遍，应该被识别。