[Evaluation of a cut-off value for the plasma aldosterone-to-renin ratio in screening for primary aldosteronism in different age and gender groups].

To explore the optimal cut-off value of aldosterone-to-renin ratio (ARR) for primary aldosteronism screening in hypertensive populations stratified by sex and age. This study was a cross-sectional study. Patients who were diagnosed with hypertension from November 2016 to December 2023 at the First Affiliated Hospital of Dalian Medical University were included. Upright direct renin concentration (DRC) and plasma aldosterone concentration (PAC) were measured using chemiluminescence, and the ARR was calculated as PAC/DRC. Patients were divided into primary aldosteronism and primary hypertension groups based on the results of comprehensive screening tests and confirmatory tests (saline infusion test and/or captopril challenge test). Spearman correlation analysis was used to explore the correlation between ARR and age. Patients were stratified by age (≤40, >40 to 50, >50 to 60, and >60 years) and sex. The efficacy of ARR for primary aldosteronism screening was assessed by drawing the receiver operating characteristic curve and calculating the area under curve (), and to explore the optimal cut-off values for different ages and sexes. A total of 1 282 hypertensive patients were enrolled, aged 46.0 (37.0, 56.0) years with 746 males. ARR showed a positive correlation with age in both primary aldosteronism (=0.168, =0.007) and primary hypertension patients (=0.327, <0.001). In the general population, male patients, and female patients, the values of ARR screening for primary aldosteronism were 0.975 (95% 0.967-0.982), 0.989 (95% 0.983-0.995), 0.957 (95% 0.942-0.972), respectively. In the four groups of patients ≤40, >40 to 50, >50 to 60, and >60 years, the values of ARR screening for primary aldosteronism were 0.990 (95% 0.983-0.997), 0.973 (95% 0.958-0.988), 0.965 (95% 0.947-0.982), 0.958 (95% 0.933-0.984), respectively. In the four groups of patients aged ≤40, >40 to 50, >50 to 60, and >60 years, the optimal ARR cut-off values for primary aldosteronism screening were 2.31, 2.67, 2.94, and 3.68 (ng·dl)/(mU·L)(1 ng/dl=27.7 pmol/L), respectively. The optimal ARR cut-off values for primary aldosteronism screening were 2.37 and 2.94 (ng·dl)/(mU·L) in male and female patients, respectively. The optimal cut-off value of ARR in the screening of primary aldosteronism increases with age, and the optimal cut-off value of ARR in female patients is higher than that in male patients. The ARR cut-off value should be selected individually based on the patient's characteristics in clinical practice.