title: β1 adrenergic receptor polymorphisms and heart failure: a meta-analysis on susceptibility, response to β-blocker therapy and prognosis.
abstract: OBJECTIVE
  The risk stratification of patients for heart failure (HF) remains a challenge, as well as the anticipation of the response to β-blocker therapy. Since the pivotal role of β1 adrenergic receptor (β1-AR) in HF, many publications have studied the associations between the β1-AR polymorphisms (Ser49Gly and Arg389Gly) and HF, with inconsistent results. Thus, we performed a meta-analysis of studies to evaluate the impact of β1-AR polymorphisms on susceptibility to HF, the response to β-blocker therapy and the prognosis of HF.
  
  
  RESULTS
  Electronic databases were systematically searched before August 2011. We extracted data sets and performed meta-analysis with standardized methods. A total of 27 studies met our inclusion criteria. It was found that in East Asians, the Gly389 allele and Gly389 homozygotes significantly increased the HF risk, while the Gly389 allele and Gly389 homozygotes trended to decrease the risk of HF in whites. With the similar reduction of heart rate, overall, the Arg389 homozygotes showed a better response to β-blocker therapy. Furthermore, the Arg389 homozygotes were significantly associated with better LVEF improvement in East Asians and a mixed population. And in white people, the Arg389 homozygotes made a greater LVESd/v improvement and trended to be associated with better LVEDd/v improvement. However, the prognosis of Arg389 homozygotes HF patients was similar to those with Gly389 carriers. The Ser49Gly polymorphism did not impact the risk or prognosis of HF.
  
  
  CONCLUSIONS
  Based on our meta-analysis, the Gly389 allele and Gly389 homozygotes were risk factors in East Asians while trending to protect whites against HF. Furthermore, Arg389 homozygote is significantly associated with a favorable response to β-blocker treatment in HF patients. However, neither of the two polymorphisms is an independent predictor of the prognosis of HF.
authors: Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Public Health, Ji'nan, People's Republic of China.
authors: Wen-Nan
authors: WN
authors: Liu
authors: Kai-Li
authors: KL
authors: Fu
authors: Hai-Yang
authors: HY
authors: Gao
authors: Yuan-Yuan
authors: YY
authors: Shang
authors: Zhi-Hao
authors: ZH
authors: Wang
authors: Gui-Hua
authors: GH
authors: Jiang
authors: Yun
authors: Y
authors: Zhang
authors: Wei
authors: W
authors: Zhang
authors: Ming
authors: M
authors: Zhong
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006333:Heart Failure / Q000175:diagnosis* / Q000235:genetics / Q000628:therapy*; D006801:Humans; D011110:Polymorphism, Genetic; D011379:Prognosis; D018342:Receptors, Adrenergic, beta-1 / Q000235:genetics*; D016896:Treatment Outcome
chemical_list: D000319:Adrenergic beta-Antagonists; D018342:Receptors, Adrenergic, beta-1