title: Pulmonary embolism is associated with current morphine treatment in patients with deep vein thrombosis.
abstract: OBJECTIVE
  This study investigates the relationship between current morphine use and the risk of pulmonary embolism (PE) development in deep vein thrombosis (DVT) patients.
  
  
  METHODS
  We conducted a population-based nested case-control retrospective analysis using the Longitudinal Health Insurance Database 2000 of Taiwan. A DVT cohort of 3668 patients with no history of PE from 1998 to 2010 and the other cohort of 174 patients who subsequently developed PE were evaluated. Morphine use was designated as 'current' if the prescription duration covered the index date or ended within 30 days before the index date. Logistic regression was used to estimate the odds ratios and 95% confidence intervals (CI), and the multivariable model was applied to control for age.
  
  
  RESULTS
  Compared with non-morphine users, DVT patients who received morphine within 30 days of the index date had a 4.54-fold (95% CI = 2.30-8.97) chance of developing PE. The risk of PE development increased with an increase in cumulative dosage and in the average dosage of morphine.
  
  
  CONCLUSIONS
  The incidence of PE in DVT patients in Taiwan is associated with current morphine treatment (≤30 days) and is dependent on dosage.
authors.affiliation: Center for Drug Abuse and Addiction, China Medical University Hospital and College of Medicine, China Medical University, Taichung, Taiwan.
authors.forename: Cynthia Wei-Sheng
authors.initials: CW
authors.lastname: Lee
authors.forename: Chih-Hsin
authors.initials: CH
authors.lastname: Muo
authors.forename: Ji-An
authors.initials: JA
authors.lastname: Liang
authors.forename: Fung-Chang
authors.initials: FC
authors.lastname: Sung
authors.forename: Chia-Hung
authors.initials: CH
authors.lastname: Kao
authors.forename: Jun-Jun
authors.initials: JJ
authors.lastname: Yeh
mesh_terms: D000368:Aged; D000701:Analgesics, Opioid / Q000627:therapeutic use*; D016022:Case-Control Studies; D015331:Cohort Studies; D016208:Databases, Factual; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000627:therapeutic use*; D009313:National Health Programs; D016017:Odds Ratio; D010146:Pain / Q000188:drug therapy* / Q000209:etiology; D011655:Pulmonary Embolism / Q000453:epidemiology*; D012307:Risk Factors; D013624:Taiwan / Q000453:epidemiology; D020246:Venous Thrombosis / Q000150:complications*
chemical_list: D000701:Analgesics, Opioid; D009020:Morphine
keywords: deep vein thrombosis; morphine; nested case-control study; pulmonary embolism