title: Can familial factors account for the association of body mass index with poor mental health in men or women?
abstract: OBJECTIVE
  This study examined if associations between body mass index (BMI) and mental and physical health were independent of genetic and familial factors.
  
  
  METHODS
  Data from 2831 twins (66% female) were used in an epidemiological co-twin control design with measures of BMI and mental and physical health outcomes. Generalized estimating equation regressions assessed relationships between BMI and health outcomes controlling for interdependency among twins and demographics. Within-pair regression analyses examined the association of BMI with health outcomes controlling for genetic and familial influences.
  
  
  RESULTS
  Adjusted analyses with individual twins found associations in women between BMI and perceived stress (P=.01) and depression (P=.002), and the link between BMI and depression (P=.03) was significant in men. All physical health outcomes were significantly related to BMI. Once genetic and familial factors were taken into account, mental health outcomes were no longer significantly associated with BMI. BMI in women remained related to ratings of physical health (P=.01) and body pain (P=.004), independent of genetic and familial influences.
  
  
  CONCLUSIONS
  These findings suggest that genetic and familial factors may account for the relationship between increased weight and poor mental health.
authors.affiliation: University of Washington School of Medicine, Seattle, WA, USA.
authors.forename: Ellen
authors.initials: E
authors.lastname: Schur
authors.forename: Kathryn M
authors.initials: KM
authors.lastname: Godfrey
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Dansie
authors.forename: Dedra
authors.initials: D
authors.lastname: Buchwald
authors.forename: Sherry
authors.initials: S
authors.lastname: Pagoto
authors.forename: Niloofar
authors.initials: N
authors.lastname: Afari
mesh_terms: D000328:Adult; D015992:Body Mass Index; D002779:Cholestasis / Q000523:psychology; D003430:Cross-Sectional Studies; D003863:Depression / Q000235:genetics / Q000523:psychology; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000235:genetics* / Q000523:psychology; D009765:Obesity / Q000150:complications / Q000235:genetics / Q000523:psychology; D011014:Pneumonia / Q000523:psychology; D011569:Psychiatric Status Rating Scales; D013315:Stress, Psychological / Q000235:genetics / Q000523:psychology
keywords: Body mass index; Familial; Genetics; Mental health; Obesity