title: Gestational influenza and bipolar disorder in adult offspring.
abstract: OBJECTIVE
  Gestational influenza has been associated previously with schizophrenia in offspring, but the relationship between this exposure and bipolar disorder (BD) is unclear. The identification of gestational influenza as a risk factor for BD may have potential for preventive approaches.
  
  
  OBJECTIVE
  To test the hypothesis that maternal influenza during pregnancy is related to BD among offspring.
  
  
  METHODS
  Nested case-control study of a population-based birth cohort from the Child Health and Development Study (CHDS). From January 1, 1959, through December 31, 1966, the CHDS recruited nearly all pregnant women receiving obstetric care from the Kaiser Permanente Medical Care Plan, Northern California Region (KPNC). Data on treated maternal influenza from the CHDS were used. Potential cases with BD from the cohort were identified by database linkages of identifiers among the CHDS, Kaiser Permanente database, and a large county health care database; by a mailed questionnaire to the CHDS cohort with subsequent interviews; and from an earlier psychiatric follow-up study on this birth cohort.
  
  
  METHODS
  The CHDS, Kaiser Permanente, and county health care databases.
  
  
  METHODS
  Cases of BD (n = 92) confirmed by structured research interviews and consensus diagnosis among the 214 subjects (48% of those ascertained) who participated and control subjects (n = 722) matched on date of birth, sex, and membership in KPNC or residence in Alameda County.
  
  
  METHODS
  Influenza.
  
  
  METHODS
  Bipolar I or II disorder, BD not otherwise specified, or BD with psychotic features.
  
  
  RESULTS
  We found a significant, nearly 4-fold increase in the risk of BD (odds ratio, 3.82 [95% CI, 1.58-9.24; P = .003]) after exposure to maternal influenza at any time during pregnancy. The findings were not confounded by maternal age, race, educational level, gestational age at birth, and maternal psychiatric disorders.
  
  
  CONCLUSIONS
  Maternal influenza may be a risk factor for BD. Although replication is required, the findings suggest that prevention of maternal influenza during pregnancy may reduce the risk of BD.
authors.affiliation: Department of Virology, National Health Laboratory Service and University of KwaZulu-Natal, Albert Luthuli Central Hospital, Durban, South Africa.
authors.forename: Raveen
authors.initials: R
authors.lastname: Parboosing
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Bao
authors.forename: Ling
authors.initials: L
authors.lastname: Shen
authors.forename: Catherine A
authors.initials: CA
authors.lastname: Schaefer
authors.forename: Alan S
authors.initials: AS
authors.lastname: Brown
mesh_terms: D000328:Adult; D001714:Bipolar Disorder / Q000150:complications* / Q000453:epidemiology; D002140:California / Q000453:epidemiology; D016022:Case-Control Studies; D005260:Female; D005865:Gestational Age; D006801:Humans; D007251:Influenza, Human / Q000150:complications* / Q000151:congenital* / Q000453:epidemiology; D018811:Maternal Exposure / Q000009:adverse effects; D008954:Models, Biological; D016017:Odds Ratio; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious; D011297:Prenatal Exposure Delayed Effects / Q000523:psychology / Q000821:virology*; D015995:Prevalence; D012307:Risk Factors