Opium use as an independent risk factor for pancreatic cancer: A case-control study.

Background: Pancreatic cancer (PC) is ranked as the seventh leading cause of cancer deaths worldwide. The current study was conducted to explore the correlation between the use of opium and its derivatives (opium) and PC in Iran.
Methods: In this case-control study which was conducted in Kerman province, south east part of Iran; 176 patients with PC, and 352 healthy individuals as the control group were matched in terms of age, sex, and place of residence. A structured questionnaire including questions of opium usage, alcohol usage, cigarette smoking, and diet was used to collect the data. The relation between the use of opium and PC was adjusted for tobacco smoking, education, daily intake of fruit, vegetables, red meat, and hydrogenated fats and analyzed using the conditional logistic regression.
Results: There was a positive relationship between the opium use and the increased risk of PC (Adjusted Odds Ratio (AOR) = 4.33, 95 % CI: 2.09-8.95), which was even stronger than its association with cigarette smoking (AOR = 1.67, 95 % CI: 0.86-3.24), although their difference was not statistically significant. A significant dose-response relation was detected between the use of opium; as the relation was stronger in heavy users (AOR low users = 4.93, 95 % CI: 1.79-13.54 and AOR heavy users = 5.10, 95 % CI: 2.10-12.35). Moreover, PC was higher among participants starting the use of opium at a younger age than those who started opium at an older age (AOR = 8.03, 95 % CI: 3.19-20.23).
Conclusion: This study demonstrated that opium use is associated with a high and strong risk of PC as an independent risk factor. Further studies should be done to reduce the use of opium in Iran and other world countries.
(Copyright © 2021. Published by Elsevier Ltd.)