Opium as a risk factor for upper gastrointestinal cancers: a population-based case-control study in Iran.
BACKGROUND
Gastrointestinal cancers, including esophageal, gastric, liver and pancreatic are relatively common in Iran. Furthermore, consumption of opium and its derivatives (O&D) are considerable. This study, aimed to examine the association between consumption of O&D and the incidence of upper gastrointestinal (UGI) cancers.


METHODS
In a matched case-control study in Kerman (located in southeast of Iran), 142 patients with UGI cancers and 284 healthy people (matched in terms of age, sex and residence (urban/rural)) were recruited. Variables (using O&D, smoking, alcohol use and diet) were collected using a structured questionnaire. Conditional logistic regression models were used to assess the above mentioned association.


RESULTS
Opium use was associated with an increased risk of UGI cancers with an adjusted OR 4.0 (95% CI=2.2-7.0). A very strong dose-response relation was observed between consumption of O&D and the incidence of UGI cancers. (Three consumption levels-none, low and high; OR=18.7; 95% CI=5.5-63.3). This dose-response relationship was also strong even in patients with gastric cancers (OR=9.2; 95% CI=2.5-33.7).


CONCLUSIONS
The results of this study showed that opium consumption can be a strong risk factor for UGI cancers in Iran.
Research Center for Social Determinants of Health, Institute for Futures Studies in Health, Kerman University of Medical Sciences, Kerman, Iran, Physiology Research Center, Kerman University of Medical Sciences, Kerman, Iran. Ahaghdoost@gmail.com.
Ahmad
A
Naghibzadeh Tahami
Enviromental Health Research Center, School of Public Health, Kerman University of Medical Sciences, Kerman, Iran.
Narges
N
Khanjani
Reseach Center for Health Services Management, Institute for Futures Studies in Health, Kerman University of Medical Sciences, Kerman, Iran Department of Health Management and Economics, School of Public Health, Tehran University of Medical Sciences.
Vahid
V
Yazdi Feyzabadi
Department of Forensic Medicine, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
Masoomeh
M
Varzandeh
Research Center for Modeling in Health, Institute for Futures Studies in Health, Kerman University of Medical Sciences, Kerman, Iran.
Ali-Akbar
AA
Haghdoost
D000368:Aged; D000428:Alcohol Drinking / Q000453:epidemiology; D016022:Case-Control Studies; D004938:Esophageal Neoplasms / Q000453:epidemiology*; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D007492:Iran / Q000453:epidemiology; D008113:Liver Neoplasms / Q000453:epidemiology*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000453:epidemiology*; D009293:Opioid-Related Disorders / Q000453:epidemiology*; D009892:Opium; D010190:Pancreatic Neoplasms / Q000453:epidemiology*; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology; D013274:Stomach Neoplasms / Q000453:epidemiology*; D011795:Surveys and Questionnaires
D009892:Opium