title: Adult narcoleptic patients have increased risk of cancer: A nationwide population-based study.
abstract: BACKGROUND
  The comorbidity profile, especially cancer risk, of narcoleptic patients has seldom been explored. We used a nationwide database to evaluate the risk of cancer among adult narcoleptic patients.
  
  
  METHODS
  We conducted the cohort study using National Health Insurance Research Database from 2000 to 2009. Standardized incidence ratios (SIRs) of cancers were calculated to compare the cancer incidence of the study cohort with that of the general population.
  
  
  RESULTS
  2833 narcoleptic patients were identified after excluding patients with antecedent malignancy and age younger than 18 years old. The study cohort was observed for 15,913 person-years during a 10-year period. The median follow-up interval was 5.6 ± 3.0 years. Seventy-four cancers occurred in during the follow-up. The risk of all cancers was found significantly increased in adult narcoleptic patients (SIR 1.32; 95% CI, 1.04-1.66, p=0.0248). Regarding sex, the overall cancer risk was increased in female patients (SIR 1.52; 95% CI, 1.05-2.13, p=0.026). Furthermore, females were found to have more head and neck cancers (SIR 6.17; 95% CI, 1.66-15.80, p=0.009) and gastric cancers (SIR 4.87; 95% CI, 1.31-12.48, p=0.02). For males, the incidence of overall and specific cancer types was not significantly increased.
  
  
  CONCLUSIONS
  Adult narcoleptic patients had a higher risk for cancer. Further research is warranted to elucidate the mechanism underlying its association.
authors.affiliation: Division of Respiratory Therapy, Department of Medicine, Cheng Hsin General Hospital, Taipei, Taiwan; School of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Ching-Min
authors.initials: CM
authors.lastname: Tseng
authors.affiliation: Department of Medicine, Taipei City Hospital Heping Fuyou Branch, Taipei, Taiwan; School of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Yung-Tai
authors.initials: YT
authors.lastname: Chen
authors.affiliation: Division of Respiratory Therapy, Department of Medicine, Cheng Hsin General Hospital, Taipei, Taiwan.
authors.forename: Chi-Wei
authors.initials: CW
authors.lastname: Tao
authors.affiliation: Division of Nephrology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; School of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Shuo-Ming
authors.initials: SM
authors.lastname: Ou
authors.affiliation: Department of Chest Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; School of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Yi-Han
authors.initials: YH
authors.lastname: Hsiao
authors.affiliation: Division of Nephrology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Szu-Yuan
authors.initials: SY
authors.lastname: Li
authors.affiliation: Department of Family Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; School of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Tzeng-Ji
authors.initials: TJ
authors.lastname: Chen
authors.affiliation: Department of Chest Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; School of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Diahn-Warng
authors.initials: DW
authors.lastname: Perng
authors.affiliation: Department of Chest Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; School of Medicine, National Yang-Ming University, Taipei, Taiwan; Center of Sleep Medicine, Taipei Veterans General Hospital, Taipei, Taiwan. Electronic address: hbjoue@vghtpe.gov.tw.
authors.forename: Kun-Ta
authors.initials: KT
authors.lastname: Chou
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D016208:Databases, Factual; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009290:Narcolepsy / Q000150:complications*; D009369:Neoplasms / Q000453:epidemiology*; D012307:Risk Factors
keywords: Cancer risk; Comorbidity; Morbidity; Mortality; Narcolepsy