title: Candesartan versus imidapril in hypertension: a randomised study to assess effects of anti-AT1 receptor autoantibodies.
abstract: BACKGROUND
  Anti-angiotensin II receptor subtype 1 (AT1 receptor) autoantibodies have previously been shown in sera of hypertensive patients. This study assessed whether anti-AT1-receptor autoantibody in serum is correlated with the efficacy of an AT1-receptor blocker (ARB; candesartan)-based regimen in hypertensive patients after 8 weeks of treatment.
  
  
  METHODS
  The Study of Optimal Treatment in Hypertensive Patients with Anti-AT1-Receptor Autoantibodies is a multicentre, randomised, blinded endpoint, open-label, parallel-group comparison clinical trial conducted in five centres in Wuhan, China. Treatment is designed as stepwise added-on therapy to reduce blood pressure (BP) < 140/90 mm Hg. 512 patients with moderate to severe primary hypertension were randomly assigned to an 8-week treatment with either ARB (candesartan)-based regimen (n=257) or ACE inhibitor (imidapril)-based regimen (n=255).
  
  
  RESULTS
  Systolic and diastolic BP was reduced significantly in both treatment groups. The candesartan-based regimen achieved a significantly greater systolic BP reduction than imdapril (30.8 ± 10.3 vs 28.8 ± 10.3 mm Hg, p = 0.023). In those anti-AT1 receptor autoantibody-positive hypertensive patients, the mean systolic BP at baseline was higher than in the anti-AT1 receptor autoantibody-negative group (160.5 ± 16.5 vs 156.2 ± 17.7 mm Hg; p = 0.006). The mean BP reduction was greater in the candesartan-based regimen than the imidapril-based regimen (-35.4 ± 9.8/16.9 ± 6.9 vs -29.4 ± 9.8/14.2 ± 6.9 mm Hg; p = 0.000 and 0.002, respectively), and more patients on imidapril required add-on medications to achieve BP control (94% vs 86%; p=0.03). No correlation was observed between the titre of anti-AT1 receptor autoantibody and the efficacy of candesartan-based therapy. In those anti-AT1 receptor autoantibody-negative patients similar BP lowering was reached in the candesartan and the imidapril-based regimens.
  
  
  CONCLUSIONS
  An ARB-based regimen is more effective in BP lowering than an ACE inhibitor-based regimen in the presence of anti-AT1 receptor autoantibodies. Trial registration number This trial has been registered at http://www.register.clinicaltrials.gov/ (identifier: NCT00360763).
authors.affiliation: Institute of Cardiology, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Wuhan 430022, China.
authors.forename: Fen
authors.initials: F
authors.lastname: Wei
authors.forename: Xiu-Jie
authors.initials: XJ
authors.lastname: Jia
authors.forename: Su-Qin
authors.initials: SQ
authors.lastname: Yu
authors.forename: Ye
authors.initials: Y
authors.lastname: Gu
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.forename: Xiao-Mei
authors.initials: XM
authors.lastname: Guo
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.forename: Feng
authors.initials: F
authors.lastname: Zhu
authors.forename: Xiang
authors.initials: X
authors.lastname: Cheng
authors.forename: Yu-Miao
authors.initials: YM
authors.lastname: Wei
authors.forename: Zi-Hua
authors.initials: ZH
authors.lastname: Zhou
authors.forename: Micheal
authors.initials: M
authors.lastname: Fu
authors.forename: Yu-Hua
authors.initials: YH
authors.lastname: Liao
mesh_terms: D000328:Adult; D000368:Aged; D047228:Angiotensin II Type 1 Receptor Blockers / Q000627:therapeutic use; D000959:Antihypertensive Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001323:Autoantibodies / Q000097:blood*; D001562:Benzimidazoles / Q000009:adverse effects / Q000627:therapeutic use*; D001713:Biphenyl Compounds; D001794:Blood Pressure / Q000187:drug effects; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000276:immunology / Q000503:physiopathology; D048289:Imidazolidines / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D044140:Receptor, Angiotensin, Type 1 / Q000276:immunology*; D013777:Tetrazoles / Q000009:adverse effects / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D047228:Angiotensin II Type 1 Receptor Blockers; D000959:Antihypertensive Agents; D001323:Autoantibodies; D001562:Benzimidazoles; D001713:Biphenyl Compounds; D048289:Imidazolidines; D044140:Receptor, Angiotensin, Type 1; D013777:Tetrazoles; C065166:imidapril; C081643:candesartan