title: Opium use and mortality in Golestan Cohort Study: prospective cohort study of 50,000 adults in Iran.
abstract: OBJECTIVE
  To investigate the association between opium use and subsequent risk of death.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  The Golestan Cohort Study in north-eastern Iran collected detailed validated data on opium use and other exposures at baseline. Participants were enrolled between January 2004 and June 2008 and were followed to May 2011, with a follow-up success rate of over 99%.
  
  
  METHODS
  50,045 participants aged 40-75 at baseline.
  
  
  RESULTS
  Mortality, all cause and major subcategories.
  
  
  RESULTS
  17% (n = 8487) of the participants reported opium use, with a mean duration of 12.7 years. During the follow-up period 2145 deaths were reported. The adjusted hazard ratio for all cause mortality associated with ever use of opium was 1.86 (95% confidence interval 1.68 to 2.06). Opium consumption was significantly associated with increased risks of deaths from several causes including circulatory diseases (hazard ratio 1.81) and cancer (1.61). The strongest associations were seen with deaths from asthma, tuberculosis, and chronic obstructive pulmonary disease (11.0, 6.22, and 5.44, respectively). After exclusion of people who self prescribed opium after the onset of major chronic illnesses, the associations remained strong with a dose-response relation.
  
  
  CONCLUSIONS
  Opium users have an increased risk of death from multiple causes compared with non-users. Increased risks were also seen in people who used low amounts of opium for a long period and those who had no major illness before use.
authors.affiliation: Digestive Disease Research Centre, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Hooman
authors.initials: H
authors.lastname: Khademi
authors.forename: Reza
authors.initials: R
authors.lastname: Malekzadeh
authors.forename: Akram
authors.initials: A
authors.lastname: Pourshams
authors.forename: Elham
authors.initials: E
authors.lastname: Jafari
authors.forename: Rasool
authors.initials: R
authors.lastname: Salahi
authors.forename: Shahryar
authors.initials: S
authors.lastname: Semnani
authors.forename: Behrooz
authors.initials: B
authors.lastname: Abaie
authors.forename: Farhad
authors.initials: F
authors.lastname: Islami
authors.forename: Siavosh
authors.initials: S
authors.lastname: Nasseri-Moghaddam
authors.forename: Arash
authors.initials: A
authors.lastname: Etemadi
authors.forename: Graham
authors.initials: G
authors.lastname: Byrnes
authors.forename: Christian C
authors.initials: CC
authors.lastname: Abnet
authors.forename: Sanford M
authors.initials: SM
authors.lastname: Dawsey
authors.forename: Nicholas E
authors.initials: NE
authors.lastname: Day
authors.forename: Paul D
authors.initials: PD
authors.lastname: Pharoah
authors.forename: Paolo
authors.initials: P
authors.lastname: Boffetta
authors.forename: Paul
authors.initials: P
authors.lastname: Brennan
authors.forename: Farin
authors.initials: F
authors.lastname: Kamangar
mesh_terms: D000328:Adult; D002423:Cause of Death; D004305:Dose-Response Relationship, Drug; D005260:Female; D005500:Follow-Up Studies; D006306:Health Surveys; D006801:Humans; D007492:Iran / Q000453:epidemiology; D008297:Male; D009293:Opioid-Related Disorders / Q000401:mortality*; D009892:Opium / Q000009:adverse effects*; D016016:Proportional Hazards Models; D011446:Prospective Studies; D011795:Surveys and Questionnaires
chemical_list: D009892:Opium