title: Modest increase in risk of acute coronary syndrome associated with morphine use in cancer patients: a population-based nested case-control study.
abstract: BACKGROUND
  Morphine is widely used for pain management in cancer patients. Use of heroin, a morphine derivative, is a risk factor for acute coronary syndrome (ACS).
  
  
  OBJECTIVE
  This study investigates the risk of ACS associated with morphine use by comparing the incidence of ACS in cancer patients treated with and without morphine.
  
  
  METHODS
  This is a population-based nested case-control study using the Longitudinal Health Insurance Database 2000 in Taiwan. In total, 31,384 patients on the database were diagnosed with cancer without prior history of ACS during 1998-2010. In this cohort, 499 patients subsequently developed ACS and 30,885 patients did not. The 499 patients were designated as the ACS group; controls were selected from the remaining 30,885 patients and matched 3:1 to each case for age, sex, year of cancer diagnosis, and index year. Logistic regression was used to estimate the odds ratios and 95% confidence intervals, and the multivariable model was applied to control for age, sex, and Charlson comorbidity score.
  
  
  RESULTS
  Cancer patients who received morphine had a 32% higher risk of developing ACS than non-morphine users. This increase in risk was significant when evaluating the overall cancer patients, but non-significant when evaluating any specific cancer type. The risk of ACS increased significantly with increasing morphine dosage (to ≥65 mg/y).
  
  
  CONCLUSIONS
  Morphine treatment is associated with a modest increase in risk of ACS in patients with malignancy, but this association displays low significance in specific cancer types.
authors.affiliation: Center for Drug Abuse and Addiction, China Medical University Hospital, Taichung, Taiwan; College of Medicine, China Medical University, Taichung, Taiwan.
authors.forename: Cynthia Wei-Sheng
authors.initials: CW
authors.lastname: Lee
authors.affiliation: Management Office for Health Data, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Chih-Hsin
authors.initials: CH
authors.lastname: Muo
authors.affiliation: Department of Radiation Oncology, China Medical University Hospital, Taichung, Taiwan; Graduate Institute of Clinical Medicine Science and School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan.
authors.forename: Ji-An
authors.initials: JA
authors.lastname: Liang
authors.affiliation: Management Office for Health Data, China Medical University Hospital, Taichung, Taiwan; Graduate Institute of Clinical Medicine Science and School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan.
authors.forename: Fung-Chang
authors.initials: FC
authors.lastname: Sung
authors.affiliation: Graduate Institute of Clinical Medicine Science and School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan; Department of Nuclear Medicine and PET Center, China Medical University Hospital, Taichung, Taiwan. Electronic address: d10040@mail.cmuh.org.tw.
authors.forename: Chia-Hung
authors.initials: CH
authors.lastname: Kao
mesh_terms: D054058:Acute Coronary Syndrome / Q000139:chemically induced* / Q000453:epidemiology; D000368:Aged; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000009:adverse effects*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage / Q000009:adverse effects*; D009369:Neoplasms / Q000150:complications*; D010146:Pain / Q000188:drug therapy* / Q000209:etiology; D059408:Pain Management / Q000379:methods*; D012306:Risk; D012307:Risk Factors; D013624:Taiwan
chemical_list: D000701:Analgesics, Opioid; D009020:Morphine
keywords: Acute coronary syndrome; Cancers; Morphine; Pain management