title: Risk of cancer among patients with depressive disorder: a meta-analysis and implications.
abstract: The question of cancer risk in individuals with depression is unclear, primarily because of the heterogeneity of the assessment of depression in the published literature. To clarify the mixed findings, this analysis was limited to articles that used a reliable method of ascertaining depressive disorder.
  
  
  
  We searched PubMed, EMBASE, and the Cochrane Library to identify studies investigating the effect of depression on subsequent risk of cancer, defining depression based on the criteria in the Diagnostic and Statistical Manual of Mental Disorders (DSM) and/or the International Classification of Disease (ICD). We calculated a pooled odds ratio (OR) for developing cancer with the 95% confidence interval (CI).
  
  
  
  Nine studies fulfilled the eligibility criteria. In a random-effects model, patients with depressive disorder were at increased risk for cancer (OR, 1.26; 95% CI, 1.06-1.50, P = 0.01). However, a significant effect was observed only in low-quality studies (OR, 1.31; 95% CI, 1.05-1.63, P = 0.018), and not in high-quality studies (OR, 1.15; 95% CI, 0.85-1.56, P = 0.366).
  
  
  
  Our results did not demonstrate that people with depressive disorder are at increased risk for developing cancer. Well-designed prospective studies of recurrent or persistent depressive disorder that control for lifestyle factors including smoking are warranted. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: Division of Hematology and Oncology, Department of Internal Medicine, Gachon University Gil Medical Center, Incheon, Korea.
authors.forename: Hee Kyung
authors.initials: HK
authors.lastname: Ahn
authors.affiliation: Department of Ophthalmology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jeong Hun
authors.initials: JH
authors.lastname: Bae
authors.affiliation: Department of Statistics, Dongguk University, Seoul, Korea.
authors.forename: Hong Yup
authors.initials: HY
authors.lastname: Ahn
authors.affiliation: Department of Family Medicine, Gachon University Gil Medical Center, Incheon, Korea.
authors.forename: In Cheol
authors.initials: IC
authors.lastname: Hwang
mesh_terms: D003866:Depressive Disorder / Q000453:epidemiology* / Q000523:psychology*; D015438:Health Behavior; D006801:Humans; D008019:Life Style; D009369:Neoplasms / Q000453:epidemiology* / Q000523:psychology*; D011446:Prospective Studies; D036301:Qualitative Research; D012306:Risk; D012907:Smoking / Q000009:adverse effects / Q000453:epidemiology