title: Adult body mass index trajectories and sexual orientation: the Nurses' Health Study II.
abstract: BACKGROUND
  Cross-sectional research has documented elevated prevalence of obesity in lesbian and bisexual women relative to heterosexual women, but little is known about disparities in longitudinal patterns in BMI change during adulthood.
  
  
  OBJECTIVE
  To examine sexual orientation-related disparities in individual BMI trajectories throughout adulthood.
  
  
  METHODS
  Data on BMI, sexual orientation, and sociodemographics were gathered prospectively from 1989 through 2005 from 90,713 U.S. women in the Nurses' Health Study II and examined in 2011 using general growth mixture modeling to identify BMI trajectories from ages 25 to 59 years. Multinomial logistic regression was used to determine whether sexual orientation was associated with BMI trajectory group membership.
  
  
  RESULTS
  Four BMI trajectory groups were identified and labeled based on mean BMI within each group at baseline and final follow-up: Group 1: slow-weight-gain trajectory; Group 2: moderate-weight-gain trajectory; Group 3: rapid-weight-gain trajectory; and Group 4: obese-to-overweight trajectory. Lesbian and bisexual women showed consistently higher odds of membership in Groups 2-4 (adverse-weight-gain trajectories) versus Group 1 (the slow-weight-gain trajectory) relative to heterosexual women.
  
  
  CONCLUSIONS
  Both lesbian and bisexual women were more likely than heterosexual women to experience adverse-weight-gain trajectories in adulthood. New research efforts are needed to understand and eliminate these pronounced disparities.
authors.affiliation: Channing Laboratory, Brigham and Women's Hospital/Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Hee-Jin
authors.initials: HJ
authors.lastname: Jun
authors.forename: Heather L
authors.initials: HL
authors.lastname: Corliss
authors.forename: Lauren P
authors.initials: LP
authors.lastname: Nichols
authors.forename: Mathew J
authors.initials: MJ
authors.lastname: Pazaris
authors.forename: Donna
authors.initials: D
authors.lastname: Spiegelman
authors.forename: S Bryn
authors.initials: SB
authors.lastname: Austin
mesh_terms: D000328:Adult; D000367:Age Factors; D001727:Bisexuality / Q000706:statistics & numerical data*; D015992:Body Mass Index; D005260:Female; D005500:Follow-Up Studies; D054624:Health Status Disparities; D020010:Heterosexuality / Q000706:statistics & numerical data; D018452:Homosexuality, Female / Q000706:statistics & numerical data*; D006801:Humans; D016015:Logistic Models; D008137:Longitudinal Studies; D008875:Middle Aged; D015233:Models, Statistical; D009765:Obesity / Q000453:epidemiology*; D050177:Overweight / Q000453:epidemiology*; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D013997:Time Factors; D015430:Weight Gain