title: Association of asthma and bipolar disorder: a nationwide population-based study in Taiwan.
abstract: BACKGROUND
  The relationship between asthma and bipolar disorder has received little research. We sought to investigate this in a large national sample. Previous studies have found mood changes after prednisone use in asthma patients, and we therefore also investigated this exposure in relation to bipolar disorder.
  
  
  METHODS
  Cases were identified from Taiwan׳s National Health Insurance Research Database with a new primary diagnosis of asthma (ICD-9:493) between 2000 and 2007. Case status required the presence of any inpatient diagnosis of asthma and/or at least one year diagnosis of asthma in outpatient service. These 46,558 cases were compared to 46,558 sex-, age-, residence- and insurance premium-matched controls and both groups were followed until the end of 2008 for first diagnosis of bipolar disorder (ICD-9 codes 296.0 to 296.16, 296.4 to 296.81 and 296.89). Competing risk adjusted Cox regression analyses were applied, adjusting for sex, age, residence, insurance premium, prednisone, hyperthyroidism, COPD (chronic obstructive pulmonary disease), Charlson comorbidity index, and hospital admission days for any disorder.
  
  
  RESULTS
  Of the 93,116 subjects, 161 were ascertained as having bipolar disorder during a mean (SD) follow-up period of 5.7 (2.2) years. Asthma was an independent risk for bipolar disorder in the fully adjusted model. Higher daily dose of prednisone was a risk factor in asthma cases.
  
  
  CONCLUSIONS
  The severity of asthma and bipolar disorder, and the route/duration of prednisone treatment were not evaluated.
  
  
  CONCLUSIONS
  Asthma was associated with increased risk of bipolar disorder. Higher daily dose of prednisone was associated with a further increased risk.
authors.affiliation: Department of Psychiatry, Chung Shan Medical University Hospital, No.110, Sec.1, Jianguo N. Rd., Taichung 40201, Taiwan; Department of Psychiatry, School of Medicine, Chung Shan Medical University, Taichung, Taiwan.
authors.forename: Tzu-Chin
authors.initials: TC
authors.lastname: Lin
authors.affiliation: Department of Public Health, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Charles Tzu-Chi
authors.initials: CT
authors.lastname: Lee
authors.affiliation: Department of Psychiatry, Chung Shan Medical University Hospital, No.110, Sec.1, Jianguo N. Rd., Taichung 40201, Taiwan; Department of Psychiatry, School of Medicine, Chung Shan Medical University, Taichung, Taiwan; Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan.
authors.forename: Te-Jen
authors.initials: TJ
authors.lastname: Lai
authors.affiliation: Department of Psychiatry, Chung Shan Medical University Hospital, No.110, Sec.1, Jianguo N. Rd., Taichung 40201, Taiwan; Department of Psychiatry, School of Medicine, Chung Shan Medical University, Taichung, Taiwan.
authors.forename: Chun-Te
authors.initials: CT
authors.lastname: Lee
authors.affiliation: Division of Pulmonary Medicine, Department of Internal Medicine, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan; Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
authors.forename: Kang-Yun
authors.initials: KY
authors.lastname: Lee
authors.affiliation: Department of Psychiatry, Chung Shan Medical University Hospital, No.110, Sec.1, Jianguo N. Rd., Taichung 40201, Taiwan; Department of Psychiatry, School of Medicine, Chung Shan Medical University, Taichung, Taiwan; Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan. Electronic address: hjcch@yahoo.com.tw.
authors.forename: Vincent Chin-Hung
authors.initials: VC
authors.lastname: Chen
authors.affiliation: Institute of Psychiatry, King׳s College London, London, UK.
authors.forename: Robert
authors.initials: R
authors.lastname: Stewart
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage / Q000009:adverse effects*; D001249:Asthma / Q000150:complications* / Q000453:epidemiology*; D001714:Bipolar Disorder / Q000139:chemically induced / Q000453:epidemiology* / Q000209:etiology*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D006980:Hyperthyroidism / Q000150:complications / Q000453:epidemiology; D007223:Infant; D038801:International Classification of Diseases; D008297:Male; D008875:Middle Aged; D011241:Prednisone / Q000008:administration & dosage / Q000009:adverse effects*; D016016:Proportional Hazards Models; D018570:Risk Assessment; D012307:Risk Factors; D013624:Taiwan / Q000453:epidemiology; D055815:Young Adult
chemical_list: D018927:Anti-Asthmatic Agents; D011241:Prednisone
keywords: Asthma; Bipolar disorder; Prednisone