title: Effect of ghrelin on mortality and cardiovascular outcomes in experimental rat and mice models of heart failure: a systematic review and meta-analysis.
abstract: BACKGROUND
  Heart failure (HF) continues to be a challenging condition in terms of prevention and management of the disease. Studies have demonstrated various cardio-protective effects of Ghrelin. The aim of the study is to determine the effect of Ghrelin on mortality and cardiac function in experimental rats/mice models of HF.
  
  
  METHODS
  Data sources: PUBMED, Scopus. We searched the Digital Dissertations and conference proceedings on Web of Science. Search methods: We systematically searched for all controlled trials (upto November 2014) which assessed the effects of Ghrelin (irrespective of dose, form, frequency, duration and route of administration) on mortality and cardiac function in rats/ mice models of HF. Ghrelin administration irrespective of dose, form, frequency, duration and route of administration. Data collection and analysis: Two authors independently assessed each abstract for eligibility and extracted data on characteristics of the experimental model used, intervention and outcome measures. We assessed the methodological quality by SYRCLE's risk of bias tool for all studies and the quality of evidence by GRADEpro. We performed meta-analysis using RevMan 5.3.
  
  
  RESULTS
  A total of 325 animals (rats and mice) were analyzed across seven studies. The meta-analysis revealed that the mortality in Ghrelin group was 31.1% and in control group was 40% (RR 0.83, 95% CI 0.46 to 1.47) i.e Ghrelin group had 68 fewer deaths per 1000 (from 216 fewer to 188 more) as compared to the control group. The meta-analysis reveals that the heart rate in rats/mice on Ghrelin was higher (MD 13.11, 95% CI 1.14 to 25.08, P=0.66) while the mean arterial blood pressure (MD -1.38, 95% CI -5.16 to 2.41, P=0.48) and left ventricular end diastolic pressure (MD -2.45, 95% CI -4.46 to -0.43, P=0.02) were lower as compared to the those on placebo. There were insignificant changes in cardiac output (SMD 0.28, 95% CI -0.24 to 0.80, P=0.29) and left ventricular end systolic pressure (MD 1.48, 95% CI -3.86 to 6.82, P=0.59).
  
  
  CONCLUSIONS
  The existing data provides evidence to suggest that Ghrelin may lower the risk of mortality and improve cardiovascular outcomes. However; the quality of evidence as assessed by GRADEpro is low to very low. Clinical judgments to administer Ghrelin to patients with HF must be made on better designed animal studies.
authors.affiliation: Department of Physiology, Datta Meghe Institute of Medical Sciences, Wardha, Maharashtra State, India.
authors.forename: Mahalaqua Nazli
authors.initials: MN
authors.lastname: Khatib
authors.affiliation: Department of Nutrition, Harvard School of Public Health, Harvard University, Cambridge, Massachusetts, United States of America.
authors.forename: Anuraj
authors.initials: A
authors.lastname: Shankar
authors.affiliation: South Asian Cochrane Centre, Christian Medical College, Vellore, India.
authors.forename: Richard
authors.initials: R
authors.lastname: Kirubakaran
authors.affiliation: Department Biostatistics, University of Western Sydney, Sydney, Australia.
authors.forename: Kingsley
authors.initials: K
authors.lastname: Agho
authors.affiliation: Centre for Public Health, Liverpool John Moores University, Liverpool, United Kingdom.
authors.forename: Padam
authors.initials: P
authors.lastname: Simkhada
authors.affiliation: Department of Medicine, Datta Meghe Institute of Medical Sciences, Wardha, Maharashtra State, India.
authors.forename: Shilpa
authors.initials: S
authors.lastname: Gaidhane
authors.affiliation: Indian Institute of Public Health-Gandhinagar, Public Health Foundation of India, New Delhi, India.
authors.forename: Deepak
authors.initials: D
authors.lastname: Saxena
authors.affiliation: Department of Community Medicine, Manipal University, Manipal, India.
authors.forename: Unnikrishnan
authors.initials: U
authors.lastname: B
authors.affiliation: Datta Meghe Institute of Medical Sciences, Wardha, Maharashtra State, India.
authors.forename: Dilip
authors.initials: D
authors.lastname: Gode
authors.affiliation: Department of Community Medicine, Datta Meghe Institute of Medical Sciences, Wardha, Maharashtra State, India.
authors.forename: Abhay
authors.initials: A
authors.lastname: Gaidhane
authors.affiliation: Department of Community Medicine, Datta Meghe Institute of Medical Sciences, Wardha, Maharashtra State, India.
authors.forename: Syed Quazi
authors.initials: SQ
authors.lastname: Zahiruddin
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002316:Cardiotonic Agents / Q000494:pharmacology*; D004195:Disease Models, Animal; D054439:Ghrelin / Q000008:administration & dosage / Q000494:pharmacology*; D006333:Heart Failure / Q000188:drug therapy* / Q000401:mortality*; D006339:Heart Rate / Q000187:drug effects; D051379:Mice; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D016277:Ventricular Function, Left
chemical_list: D002316:Cardiotonic Agents; D054439:Ghrelin