title: Prevalence of and risk factors for primary aldosteronism among patients with resistant hypertension in China.
abstract: OBJECTIVE
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department 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, Shanghai, China.
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Sang
authors.forename: Yiran
authors.initials: Y
authors.lastname: Jiang
authors.forename: Weiqing
authors.initials: W
authors.lastname: Wang
authors.forename: Li
authors.initials: L
authors.lastname: Yan
authors.forename: Jiasheng
authors.initials: J
authors.lastname: Zhao
authors.forename: Yongde
authors.initials: Y
authors.lastname: Peng
authors.forename: Wei
authors.initials: W
authors.lastname: Gu
authors.forename: Gang
authors.initials: G
authors.lastname: Chen
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Guang
authors.initials: G
authors.lastname: Ning
mesh_terms: D002681:China / Q000453:epidemiology; D005260:Female; D006801:Humans; D006929:Hyperaldosteronism / Q000150:complications / Q000453:epidemiology*; D006973:Hypertension / Q000150:complications / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors