Hypertension is the most common cardiovascular disease, with the number of patients increased from 650 million in 1990 to 1.3 billion in 2019, and it is expected to exceed 1.5 billion by 2025.1, 2, 3 Hypertension can significantly increase the risk of complications such as heart failure, stroke, and kidney failure.4,5 Almost 3 times as many people in low- and middle-income countries suffer from hypertension than in high-income countries, highlighting the severe burden of the disease in these regions.6 In China, the prevalence of hypertension continues to climb as the population ages, lifestyle changes and urbanization accelerate, placing a huge burden on China’s health care system.7 Although genetic, lifestyle, and environmental factors play an important role in the onset and development of hypertension, the influence of abnormal regulation of the endocrine system in the pathophysiological process of hypertension and its complications are not ignorable, particularly dysregulation of the Renin-Angiotensin-Aldosterone System (RAAS).8

Aldosterone and renin are 2 key molecules in the RAAS, and their abnormal secretion is closely associated with the development of hypertension.9 Aldosterone promotes sodium retention, while renin initiates the angiotensin cascade and contributes to blood pressure (BP) regulation.10,11 The aldosterone-to-renin ratio (ARR) is widely used to assess the state of aldosterone secretion and is particularly important in the diagnosis of primary aldosteronism (PA).12 In addition, glucocorticoids are also imperative for BP regulation.13 However, the contributions of aldosterone, renin and their ratios to the various BP phenotypes and hypertension phenotypes has not been well investigated in large scale Chinese adult population, especially in the economically underdeveloped southwestern regions.

Although previous studies have examined the relationship between aldosterone, renin and BP, the study participants were mainly non-Chinese with relatively small sample sizes (n < 2000),14, 15, 16 and the proportion of Chinese hypertensive patients with salt sensitivity is high, which may directly affect RAAS activity and thus could not reflect their true associations to some degree. In this study, we attempted to systematically examine the associations of plasma aldosterone concentration (PAC), plasma renin concentration (PRC), and ARR with BP-related phenotypes using the cross-sectional data of a large-scale population of Chinese adults from Hakka Biobank (HKB) cohort in Guangxi, China; further restricted cubic spline (RCS), subgroup and sensitivity analyses were performed to consolidate their associations.