Objectives: It is estimated that there are more than 16 million adults with drug-resistant hypertension in China. Nevertheless, the prevalence of and risk factors for primary aldosteronism, a highly curable condition among adults with drug-resistant hypertension, has not been fully investigated.
Methods: Between January 2010 and October 2011, a multicenter epidemiologic study was conducted among 1656 patients with resistant hypertension in 11 provinces of China. Serum aldosterone and plasma renin activity were measured in every participant and aldosterone-to-renin ratio (ARR) was calculated. Patients with ARR more than 20 underwent an intravenous (i.v.) sodium infusion test, and diagnosis of primary aldosteronism was established by the presence of unsuppressed postinfusion aldosterone (>8 ng/dl). Patients with biochemically proved primary aldosteronism then underwent adrenal computed tomography (CT) scanning and adrenal vein sampling (AVS) for subtype classification.
Results: Among the 1656 patients, 494 (29.8%) had ARR greater than 20 and underwent i.v. sodium infusion. Of these 494, 118 were diagnosed as primary aldosteronism, yielding a prevalence of 7.1% (95% confidential interval 5.9–8.3%). Seventy of the 118 patients were categorized into unilateral (39) and bilateral (31) by AVS. Generalized additive regression analysis revealed that among all the factors investigated (age of hypertension onset, BMI, family history of hypertension, cigarette smoking, alcohol consumption, diabetes, serum potassium, hyperlipidemia, and creatinine), only age of hypertension onset and serum potassium were independently associated with the presence of primary aldosteronism.
Conclusion: The prevalence of primary aldosteronism among Chinese patients with resistant hypertension is relatively lower than that reported previously for other ethnic populations. The screening for primary aldosteronism should be focused on those with early onset hypertension and/or hypokalemia.
aDepartment of Endocrinology and Metabolism, Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Ruijin Hospital Affiliated to Shanghai Jiao-Tong University School of Medicine
bDepartment of Endocrinology and Metabolism, The Second Affiliated Hospital of Sun Yat-sen University
cDepartment of Endocrinology and Metabolism, Tongji Hospital, affiliated to Shanghai Tong Ji University School of Medicine
dDepartment of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated First People's Hospital
eDepartment of Endocrinology and Metabolism, The Second Affiliated Hospital, School of Medicine, Zhejiang University
fDepartment of Endocrinology, Fujian Provincial Hospital, Fujian Medical University
gDepartment of Endocrinology and Metabolism, Renji hospital, affiliated to Shanghai Jiao Tong University School of Medicine
*Xiaojing Sang and Yiran Jiang contributed equally to this work.
Correspondence to Guang Ning, PhD, MD, Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrinology and Metabolism, Ruijin Hospital Affiliated to Shanghai Jiao-Tong University School of Medicine, 197 Ruijin 2nd Road, Shanghai 200025, China. Tel: +086 21 64370045, ext 665340; fax: +086 21 64373514; e-mail: email@example.com
Abbreviations: APA, aldosterone producing adenoma; ARR, aldosterone/renin activity ratio; AVS, adrenal vein sampling; CI, confidential intervals; EH, essential hypertension; GLM, generalized linear models; IHA, idiopathic hyperaldosteronism; IQR, interquartile ranges; PA, primary aldosteronism; UAH, unilateral adrenal hyperplasia
Received 27 October, 2012
Revised 3 February, 2013
Accepted 4 March, 2013