title: Risk of Celiac Disease in the First- and Second-Degree Relatives of Patients With Celiac Disease: A Systematic Review and Meta-Analysis.
abstract: OBJECTIVE
  First-degree relatives (FDRs) of patients with celiac disease (CD) are at high risk for CD and prevalence among them varies from 1.6 to 38%. The risk of having CD among FDRs if the FDR is sister, brother, mother, father, son, or daughter of index patient with CD is not known. We conducted a meta-analysis and calculated pooled prevalence of CD among FDRs, second-degree relatives (SDRs), and specific relations with index patient.
  
  
  METHODS
  On search of literature, 2,259 articles appeared of which 54 articles were included in this meta-analysis. Diagnosis of CD was based on standard criteria.
  
  
  RESULTS
  Pooled prevalence of CD was 7.5% (95% confidence interval (CI) 6.3%, 8.8%) in 10,252 FDRs and 2.3% (95% CI 1.3%, 3.8%) in 642 SDRs. Pooled prevalence of CD was highest in siblings (8.9%), followed by offsprings (7.9%) and parents (3.0%). Female FDRs had higher prevalence than male FDRs (8.4% vs. 5.2%, P=0.047). While sisters and daughters of index patient had the highest risk of having CD (1 in 7 and 1 in 8, respectively), the risk was 1 in 13 in sons, 1 in 16 in brothers, 1 in 32 in mothers, and 1 in 33 in fathers. There were also differences in the pooled prevalence of CD in FDRs according to their geographic location.
  
  
  CONCLUSIONS
  Pooled prevalence of CD among FDRs is 7.5% and varies considerably with their relationship with the index patient. The risk of CD in FDRs also varies according to gender and geographical location.
authors.affiliation: Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA.
authors.forename: Prashant
authors.initials: P
authors.lastname: Singh
authors.affiliation: Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA.
authors.forename: Shubhangi
authors.initials: S
authors.lastname: Arora
authors.affiliation: Max Healthcare, Gurgaon, India.
authors.forename: Suman
authors.initials: S
authors.lastname: Lal
authors.affiliation: Medical Services Division, Innlandet Hospital Trust, Lillehammer, Norway.
authors.forename: Tor A
authors.initials: TA
authors.lastname: Strand
authors.affiliation: Department of Gastroenterology and Human Nutrition, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Govind K
authors.initials: GK
authors.lastname: Makharia
mesh_terms: D001208:Asia / Q000453:epidemiology; D002446:Celiac Disease / Q000453:epidemiology* / Q000235:genetics*; D005060:Europe / Q000453:epidemiology; D005220:Fathers; D005260:Female; D006801:Humans; D008297:Male; D009035:Mothers; D009656:North America / Q000453:epidemiology; D010375:Pedigree; D015995:Prevalence; D012307:Risk Factors; D012737:Sex Factors; D035781:Siblings; D013020:South America / Q000453:epidemiology