title: Genetic mutations in African patients with atrial fibrillation: Rationale and design of the Study of Genetics of Atrial Fibrillation in an African Population (SIGNAL).
abstract: BACKGROUND
  There is an urgent need to understand genetic associations with atrial fibrillation in ethnically diverse populations. There are no such data from sub-Saharan Africa, despite the fact that atrial fibrillation is one of the fastest growing diseases. Moreover, patients with valvular heart disease are underrepresented in studies of the genetics of atrial fibrillation.
  
  
  METHODS
  We designed a case-control study of patients with and without a history of atrial fibrillation in Kenya. Cases with atrial fibrillation included those with and without valvular heart disease. Patients underwent clinical phenotyping and will have laboratory analysis and genetic testing of >240 candidate genes associated with cardiovascular diseases. A 12-month follow-up assessment will determine the groups' morbidity and mortality. The primary analyses will describe genetic and phenotypic associations with atrial fibrillation.
  
  
  RESULTS
  We recruited 298 participants: 72 (24%) with nonvalvular atrial fibrillation, 78 (26%) with valvular atrial fibrillation, and 148 (50%) controls without atrial fibrillation. The mean age of cases and controls were 53 and 48 years, respectively. Most (69%) participants were female. Controls more often had hypertension (45%) than did those with valvular atrial fibrillation (27%). Diabetes and current tobacco smoking were uncommon. A history of stroke was present in 25% of cases and in 5% of controls.
  
  
  CONCLUSIONS
  This is the first study determining genetic associations in valvular and nonvalvular atrial fibrillation in sub-Saharan Africa with a control population. The results advance knowledge about atrial fibrillation and will enhance international efforts to decrease atrial fibrillation-related morbidity.
authors.affiliation: Department of Medicine, Duke University, Durham, NC; Duke Clinical Research Institute and Duke Global Health Institute, Duke University, Durham, NC. Electronic address: gerald.bloomfield@duke.edu.
authors.forename: Gerald S
authors.initials: GS
authors.lastname: Bloomfield
authors.affiliation: Department of Epidemiology, Brown University School of Public Health, Providence, RI.
authors.forename: Tecla M
authors.initials: TM
authors.lastname: Temu
authors.affiliation: Division of Medicine, Moi Teaching and Referral Hospital, Eldoret, Kenya; AMPATH Partnership, Eldoret, Kenya.
authors.forename: Constantine O
authors.initials: CO
authors.lastname: Akwanalo
authors.affiliation: Krannert Institute of Cardiology, Indiana University, Indianapolis, IN; Department of Medicine, Indiana University, Indianapolis, IN.
authors.forename: Peng-Sheng
authors.initials: PS
authors.lastname: Chen
authors.affiliation: Division of Medicine, Moi Teaching and Referral Hospital, Eldoret, Kenya; AMPATH Partnership, Eldoret, Kenya.
authors.forename: Wilfred
authors.initials: W
authors.lastname: Emonyi
authors.affiliation: Department of Epidemiology, University of Washington, Seattle, WA.
authors.forename: Susan R
authors.initials: SR
authors.lastname: Heckbert
authors.affiliation: Division of Medicine, Moi Teaching and Referral Hospital, Eldoret, Kenya.
authors.forename: Myra M
authors.initials: MM
authors.lastname: Koech
authors.affiliation: Division of Medicine, Moi Teaching and Referral Hospital, Eldoret, Kenya; AMPATH Partnership, Eldoret, Kenya.
authors.forename: Imran
authors.initials: I
authors.lastname: Manji
authors.affiliation: Department of Biostatistics, Indiana University School of Medicine, Richard M. Fairbanks School of Public Health, Indiana University, Indianapolis, IN.
authors.forename: Changyu
authors.initials: C
authors.lastname: Shen
authors.affiliation: Department of Medicine, Indiana University, Indianapolis, IN; Department of Medical and Molecular Genetics, Indiana University, Indianapolis, IN.
authors.forename: Matteo
authors.initials: M
authors.lastname: Vatta
authors.affiliation: Department of Medicine, Duke University, Durham, NC; Duke Clinical Research Institute and Duke Global Health Institute, Duke University, Durham, NC.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Velazquez
authors.affiliation: Department of Medicine, Indiana University, Indianapolis, IN.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Wessel
authors.affiliation: Division of Medicine, Moi Teaching and Referral Hospital, Eldoret, Kenya; AMPATH Partnership, Eldoret, Kenya; Department of Medicine, School of Medicine, College of Health Sciences, Moi University, Eldoret, Kenya.
authors.forename: Sylvester
authors.initials: S
authors.lastname: Kimaiyo
authors.affiliation: AMPATH Partnership, Eldoret, Kenya; Department of Medicine, Indiana University, Indianapolis, IN; Department of Medicine, School of Medicine, College of Health Sciences, Moi University, Eldoret, Kenya.
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Inui
mesh_terms: D001281:Atrial Fibrillation / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics*; D004247:DNA / Q000235:genetics*; D004252:DNA Mutational Analysis; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D056726:Genetic Association Studies; D006801:Humans; D007630:Kenya / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009017:Morbidity / Q000639:trends; D009154:Mutation; D011159:Population Surveillance / Q000379:methods*; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends; D013997:Time Factors
chemical_list: D004247:DNA