Aldosterone/direct renin concentration ratio as a screening test for primary aldosteronism: a systematic review and meta-analysis

Background: Primary aldosteronism (PA) refers to a spontaneous increase in adrenal aldosterone secretion, and is considered the main cause of secondary hypertension. The main aldosterone screening methods include plasma aldosterone-to-renin ratio (ARR) and plasma aldosterone/direct renin concentration ratio (ADRR). The ARR method has many limitations such as complex operation, several influencing factors, and difficulty in standardization. Relatively speaking, ADRR has gradually attracted attention due to its simple operation, stable results, and easy standardization. However, different research results have suggested that the diagnostic efficacy of ADRR in the screening of primary aldosteronism varies greatly. Meta-analysis may be a way to provide evidence-based medicine. Therefore, it is necessary to conduct a meta-analysis of the diagnostic efficacy of ADRR in primary aldosteronism to clarify the role of ADRR in the screening of PA. Methods: The words "primary aldosteronism", "primary hyperaldosteronism", "aldosterone", "renin concentration", "hypertension" and "screening test" were used as search terms. Literature searches were conducted in the databases of PubMed, Embase, Cochrane Library, and China National Knowledge Infrastructure (CNKI), Wanfang, and Weipu. According to the PICOS principles studies exploring the effectiveness of ADRR in screening for PA were included in the analysis. The research data were independently extracted and analyzed by 2 researchers. Quality assessment of diagnostic accuracy studies (QUADAS-2) was used to analyze the risk bias of the included studies. Results: The results showed that 10 studies met the inclusion criteria, with a total of 2,806 subjects. The meta-analysis found that the overall sensitivity and specificity were 0.87 [95% confidence interval (CI): 0.85-0.89], 0.85 (95% CI: 0.83-0.86), respectively. The area under the curve (AUC) of the summary receiver operating characteristic (SROC) curve was 0.9333. The pooled positive likelihood ratio (PLR), pooled negative likelihood ratio (NLR), and pooled diagnostic odds ratio (DOR) were 5.84 (3.67-9.30), 0.16 (0.12-0.22), and 39.82 (22.84-69.44), respectively. Discussion: This study confirmed that ADRR screening for PA has good sensitivity and specificity. Therefore, ADRR can be used to screen for PA. But the risk and problematic control should be considered.