title: Parental risk factors for oral clefts among Central Africans, Southeast Asians, and Central Americans.
abstract: BACKGROUND
  Several lifestyle and environmental exposures have been suspected as risk factors for oral clefts, although few have been convincingly demonstrated. Studies across global diverse populations could offer additional insight given varying types and levels of exposures.
  
  
  METHODS
  We performed an international case-control study in the Democratic Republic of the Congo (133 cases, 301 controls), Vietnam (75 cases, 158 controls), the Philippines (102 cases, 152 controls), and Honduras (120 cases, 143 controls). Mothers were recruited from hospitals and their exposures were collected from interviewer-administered questionnaires. We used logistic regression modeling to estimate odds ratios (OR) and 95% confidence intervals (CI).
  
  
  RESULTS
  Family history of clefts was strongly associated with increased risk (maternal: OR = 4.7; 95% CI, 3.0-7.2; paternal: OR = 10.5; 95% CI, 5.9-18.8; siblings: OR = 5.3; 95% CI, 1.4-19.9). Advanced maternal age (5 year OR = 1.2; 95% CI, 1.0-1.3), pregestational hypertension (OR = 2.6; 95% CI, 1.3-5.1), and gestational seizures (OR = 2.9; 95% CI, 1.1-7.4) were statistically significant risk factors. Lower maternal (secondary school OR = 1.6; 95% CI, 1.2-2.2; primary school OR = 2.4, 95% CI, 1.6-2.8) and paternal education (OR = 1.9; 95% CI, 1.4-2.5; and OR = 1.8; 95% CI, 1.1-2.9, respectively) and paternal tobacco smoking (OR = 1.5, 95% CI, 1.1-1.9) were associated with an increased risk. No other significant associations between maternal and paternal factors were found; some environmental factors including rural residency, indoor cooking with wood, chemicals and water source appeared to be associated with an increased risk in adjusted models.
  
  
  CONCLUSIONS
  Our study represents one of the first international studies investigating risk factors for clefts among multiethnic underserved populations. Our findings suggest a multifactorial etiology including both maternal and paternal factors.
authors.affiliation: Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California.
authors.forename: Jane C
authors.initials: JC
authors.lastname: Figueiredo
authors.affiliation: Division of Plastic & Maxillofacial Surgery, Children's Hospital Los Angeles, Los Angeles, California.|Department of Community Health Sciences and California Center for Population Research, UCLA Fielding School of Public Health, Los Angeles, California.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Ly
authors.affiliation: Operation Smile, Inc, Norfolk, Virginia.
authors.forename: Kathleen S
authors.initials: KS
authors.lastname: Magee
authors.affiliation: Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California.
authors.forename: Ugonna
authors.initials: U
authors.lastname: Ihenacho
authors.affiliation: BioRealm LLC, Los Angeles, California.|Bioinformatics and Data Science Research Center, Bina Nusantara University, Jakarta, Indonesia.
authors.forename: James W
authors.initials: JW
authors.lastname: Baurley
authors.affiliation: Departments of Pediatrics and Pathology & Laboratory Medicine, Keck School of Medicine, University of Southern California, Children's Hospital Los Angeles, Los Angeles, California.
authors.forename: Pedro A
authors.initials: PA
authors.lastname: Sanchez-Lara
authors.affiliation: Division of Plastic & Maxillofacial Surgery, Children's Hospital Los Angeles, Los Angeles, California.
authors.forename: Frederick
authors.initials: F
authors.lastname: Brindopke
authors.affiliation: Operation Smile Vietnam, Hanoi, Vietnam.
authors.forename: Thi-Hai-Duc
authors.initials: TH
authors.lastname: Nguyen
authors.affiliation: Operation Smile Vietnam, Hanoi, Vietnam.
authors.forename: Viet
authors.initials: V
authors.lastname: Nguyen
authors.affiliation: Operation Smile Philippines, Manila, Philippines.|Department of Surgery, Faculty of Medicine and Surgery, University of Santo Tomas, Manila, Philippines.
authors.forename: Maria Irene
authors.initials: MI
authors.lastname: Tangco
authors.affiliation: Operación Sonrisa Honduras, Tegucigalpa, Honduras.
authors.forename: Melissa
authors.initials: M
authors.lastname: Giron
authors.affiliation: Operation Smile South Africa, Johannesburg, South Africa.
authors.forename: Tamlin
authors.initials: T
authors.lastname: Abrahams
authors.affiliation: Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California.
authors.forename: Grace
authors.initials: G
authors.lastname: Jang
authors.affiliation: Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California.
authors.forename: Annie
authors.initials: A
authors.lastname: Vu
authors.affiliation: Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California.
authors.forename: Emily
authors.initials: E
authors.lastname: Zolfaghari
authors.affiliation: Division of Plastic & Maxillofacial Surgery, Children's Hospital Los Angeles, Los Angeles, California.
authors.forename: Caroline A
authors.initials: CA
authors.lastname: Yao
authors.affiliation: Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California.
authors.forename: Athena
authors.initials: A
authors.lastname: Foong
authors.affiliation: Departments of Pediatrics and Biochemistry and Molecular Biology, Keck School of Medicine, University of Southern California and Children's Hospital Los Angeles, Los Angeles, California.
authors.forename: Yves A
authors.initials: YA
authors.lastname: DeClerk
authors.affiliation: Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California.
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Samet
authors.affiliation: Division of Plastic & Maxillofacial Surgery, Children's Hospital Los Angeles, Los Angeles, California.
authors.forename: William
authors.initials: W
authors.lastname: Magee
mesh_terms: D000328:Adult; D000350:Africa, Central; D001210:Asia, Southeastern; D044466:Asian People; D016022:Case-Control Studies; D002489:Central America; D002675:Child, Preschool; D002972:Cleft Palate / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D006801:Humans; D007197:Indians, Central American; D007199:Indians, South American; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008954:Models, Biological; D012307:Risk Factors; D012959:Socioeconomic Factors
keywords: cleft lip/palate; cleft palate; maternal health; multiethnic populations; parental risk factors