title: Overweight, obesity, and depression: a systematic review and meta-analysis of longitudinal studies.
abstract: BACKGROUND
  Association between obesity and depression has repeatedly been established. For treatment and prevention purposes, it is important to acquire more insight into their longitudinal interaction.
  
  
  OBJECTIVE
  To conduct a systematic review and meta-analysis on the longitudinal relationship between depression, overweight, and obesity and to identify possible influencing factors.
  
  
  METHODS
  Studies were found using PubMed, PsycINFO, and EMBASE databases and selected on several criteria.
  
  
  METHODS
  Studies examining the longitudinal bidirectional relation between depression and overweight (body mass index 25-29.99) or obesity (body mass index > or =30) were selected.
  
  
  METHODS
  Unadjusted and adjusted odds ratios (ORs) were extracted or provided by the authors.
  
  
  RESULTS
  Overall, unadjusted ORs were calculated and subgroup analyses were performed for the 15 included studies (N = 58 745) to estimate the effect of possible moderators (sex, age, depression severity). Obesity at baseline increased the risk of onset of depression at follow-up (unadjusted OR, 1.55; 95% confidence interval [CI], 1.22-1.98; P < .001). This association was more pronounced among Americans than among Europeans (P = .05) and for depressive disorder than for depressive symptoms (P = .05). Overweight increased the risk of onset of depression at follow-up (unadjusted OR, 1.27; 95% CI, 1.07-1.51; P < .01). This association was statistically significant among adults (aged 20-59 years and > or =60 years) but not among younger persons (aged <20 years). Baseline depression (symptoms and disorder) was not predictive of overweight over time. However, depression increased the odds for developing obesity (OR, 1.58; 95% CI, 1.33-1.87; P < .001). Subgroup analyses did not reveal specific moderators of the association.
  
  
  CONCLUSIONS
  This meta-analysis confirms a reciprocal link between depression and obesity. Obesity was found to increase the risk of depression, most pronounced among Americans and for clinically diagnosed depression. In addition, depression was found to be predictive of developing obesity.
authors.affiliation: Department of Psychiatry, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, the Netherlands. f.s.lent-luppino@lumc.nl
authors.forename: Floriana S
authors.initials: FS
authors.lastname: Luppino
authors.forename: Leonore M
authors.initials: LM
authors.lastname: de Wit
authors.forename: Paul F
authors.initials: PF
authors.lastname: Bouvy
authors.forename: Theo
authors.initials: T
authors.lastname: Stijnen
authors.forename: Pim
authors.initials: P
authors.lastname: Cuijpers
authors.forename: Brenda W J H
authors.initials: BW
authors.lastname: Penninx
authors.forename: Frans G
authors.initials: FG
authors.lastname: Zitman
mesh_terms: D000328:Adult; D015992:Body Mass Index; D015897:Comorbidity; D003866:Depressive Disorder / Q000150:complications / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000453:epidemiology* / Q000209:etiology; D050177:Overweight / Q000150:complications / Q000453:epidemiology* / Q000209:etiology; D012307:Risk Factors