title: Lithium treatment and cancer incidence in bipolar disorder.
abstract: OBJECTIVE
  To investigate whether there is an increased risk of cancer associated with lithium treatment in patients with bipolar disorder compared to the general population.
  
  
  METHODS
  A nationwide Swedish register study of incidence rate ratios (IRRs) of total cancer and site-specific cancer in the 50-84-year age range was carried out in patients with bipolar disorder (n = 5,442) with and without lithium treatment from July 2005 to December 2009 compared to the general population using linked information from The Swedish Cancer Register, The National Patient Register, and The Drug Prescription Register.
  
  
  RESULTS
  The overall cancer risk was not increased in patients with bipolar disorder. There was no difference in risk of unspecified cancer, neither in patients with lithium treatment compared to the general population [IRR = 1.04, 95% confidence interval (CI): 0.89-1.23] nor in patients with bipolar disorder without lithium treatment compared to the general population (IRR = 1.03, 95% CI: 0.89-1.19). The cancer risk was significantly increased in patients with bipolar disorder without lithium treatment in the digestive organs (IRR = 1.47, 95% CI: 1.12-1.93), in the respiratory system and intrathoracic organs (IRR = 1.72, 95% CI: 1.11-2.66), and in the endocrine glands and related structures (IRR = 2.60, 95% CI: 1.24-5.47), but in patients with bipolar disorder with lithium treatment, there was no significantly increased cancer risk compared to the general population.
  
  
  CONCLUSIONS
  Bipolar disorder was not associated with increased cancer incidence and neither was lithium treatment in these patients. Specifically, there was an increased risk of respiratory, gastrointestinal, and endocrine cancer in patients with bipolar disorder without lithium treatment.
authors.affiliation: Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.|Centre for Psychiatric Research and Education, Stockholm, Sweden.
authors.forename: Lina
authors.initials: L
authors.lastname: Martinsson
authors.affiliation: Division for Family Medicine, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Jeanette
authors.initials: J
authors.lastname: Westman
authors.affiliation: Division for Family Medicine, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Jonas
authors.initials: J
authors.lastname: Hällgren
authors.affiliation: Division for Family Medicine, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden.|Center for Molecular Medicine, Karolinska University Hospital Solna, Stockholm, Sweden.|Department of Adult Psychiatry, PRIMA Barn och Vuxenpsykiatri AB, Stockholm, Sweden.
authors.forename: Urban
authors.initials: U
authors.lastname: Ösby
authors.affiliation: Centre for Psychiatric Research and Education, Stockholm, Sweden.|Neurogenetics Unit, Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Lena
authors.initials: L
authors.lastname: Backlund
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018692:Antimanic Agents / Q000627:therapeutic use*; D001714:Bipolar Disorder / Q000188:drug therapy* / Q000453:epidemiology; D004701:Endocrine Gland Neoplasms / Q000453:epidemiology; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D018020:Lithium Compounds / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000453:epidemiology*; D065840:Protective Factors; D012042:Registries; D012142:Respiratory Tract Neoplasms / Q000453:epidemiology; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology
chemical_list: D018692:Antimanic Agents; D018020:Lithium Compounds
keywords: bipolar disorder; cancer; comorbidity; lithium; register; tumors