title: Lithium and renal and upper urinary tract tumors - results from a nationwide population-based study.
abstract: OBJECTIVE
  A recent alarming finding suggested an increased risk of renal tumors among long-term lithium users. The objectives of the present study were to estimate rates of renal and upper urinary tract tumors (RUT), malignant and benign, among individuals exposed to successive prescriptions for lithium, anticonvulsants, and other psychotropic agents used for bipolar disorder, and among unexposed individuals.
  
  
  METHODS
  This was a nationwide, population-based longitudinal study including time-specific data from all individuals exposed to lithium (n = 24,272) or anticonvulsants (n = 386,255), all individuals with a diagnosis of bipolar disorder (n = 9,651), and a randomly selected sample of 1,500,000 from the Danish population. The study period was from 1995 to 2012, inclusive. Outcomes were hazard rate ratios (HR) for RUT in three groups: (i) combined malignant and benign, (ii) malignant, and (iii) benign. Analyses were adjusted for the number of prescriptions for lithium/anticonvulsants, antipsychotic agents, antidepressants, and use of all other types of medication; age; gender; employment status; calendar year; and a diagnosis of bipolar disorder.
  
  
  RESULTS
  Continued treatment with lithium was not associated with increased rates of RUT [adjusted HR malignant or benign: 0.67-1.18, p (trend) = 0.70; adjusted HR malignant: 0.61-1.34, p (trend) = 0.90; adjusted HR benign: 0.74-1.18, p (trend) = 0.70]. Similarly, continued treatment with anticonvulsants was not associated with increased rates of RUT [adjusted HR malignant or benign: 0.97-1.18, p (trend) = 0.10; adjusted HR malignant: 0.82-1.15, p (trend) = 0.80; adjusted HR benign: 0.94-1.36, p (trend) = 0.20]. The associations were confirmed among the 9,651 patients with a diagnosis of bipolar disorder.
  
  
  CONCLUSIONS
  Treatment with lithium is not associated with increased rates of RUT.
authors.affiliation: Psychiatric Center Copenhagen, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Lars Vedel
authors.initials: LV
authors.lastname: Kessing
authors.affiliation: Department of Biostatistics, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Thomas Alexander
authors.initials: TA
authors.lastname: Gerds
authors.affiliation: Department of Nephrology, University of Copenhagen, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Bo
authors.initials: B
authors.lastname: Feldt-Rasmussen
authors.affiliation: Department of Biostatistics, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Per Kragh
authors.initials: PK
authors.lastname: Andersen
authors.affiliation: Department of Clinical Medicine, Aalborg University, Aalborg, Denmark.|Aalborg University Hospital, Psychiatry, Aalborg, Denmark.
authors.forename: Rasmus W
authors.initials: RW
authors.lastname: Licht
mesh_terms: D000328:Adult; D000927:Anticonvulsants / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D001714:Bipolar Disorder / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology; D003718:Denmark / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D018020:Lithium Compounds / Q000008:administration & dosage / Q000009:adverse effects; D000069451:Long Term Adverse Effects / Q000139:chemically induced / Q000175:diagnosis / Q000453:epidemiology / Q000473:pathology; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D016016:Proportional Hazards Models; D011619:Psychotropic Drugs / Q000008:administration & dosage / Q000009:adverse effects / Q000145:classification; D012307:Risk Factors; D012959:Socioeconomic Factors; D014571:Urologic Neoplasms / Q000145:classification / Q000453:epidemiology / Q000209:etiology / Q000473:pathology
chemical_list: D000927:Anticonvulsants; D018020:Lithium Compounds; D011619:Psychotropic Drugs
keywords: bipolar disorder; lithium; renal and upper urinary tract cancer; renal and upper urinary tract tumors; renal tumor