Maryam Hadji1,2, Hamideh Rashidian2, Maryam Marzban3,4, Ahmad Naghibzadeh-Tahami5,6, Mahin Gholipour7, Elham Mohebbi2,8, Roya Safari-Faramani9, Monireh Sadat Seyyedsalehi2, Bayan Hosseini2,10, Mahdieh Bakhshi11, Reza Alizadeh-Navaei12, Lida Ahmadi13, Abbas Rezaianzadeh13, Abdolvahab Moradi14, Alireza Ansari-Moghaddam11, Azim Nejatizadeh15, Soodabeh ShahidSales16, Farshad Zohrabi17, Reza Mohammadi18,19, Mohammad Reza Nowroozi20, Hossein Poustchi21, Dariush Nasrollahzadeh10, Farid Najafi9,22, Ali Akbar Haghdoost6,23, Afarin Rahimi-Movaghar24, Arash Etemadi25,26, Mohammad Ali Mohagheghi2, Reza Malekzadeh21,25, Paul Brennan10, Joachim Schüz10, Paolo Boffetta27,28, Elisabete Weiderpass10, Farin Kamangar29, Kazem Zendehdel2,30, Eero Pukkala1,31. 1. Health Sciences Unit, Faculty of Social Sciences, Tampere University, Tampere, Finland. 2. Cancer Research Center, Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran. 3. Department of Public Health, School of Public Health, Bushehr University of Medical Science, Bushehr, Iran. 4. Clinical Research Development Center, Persian Gulf Martyrs, Bushehr University of Medical Science, Bushehr, Iran. 5. Social Determinants of Health Research Center, Institute for Futures Studies in Health, Kerman University of Medical Sciences, Kerman, Iran. 6. Department of Biostatistics and Epidemiology, Kerman University of Medical Sciences, Kerman, Iran. 7. Metabolic Disorders Research Center, Golestan University of Medical Sciences, Gorgan, Iran. 8. Pathology and Stem Cell Research Center, Kerman University of Medical Sciences, Kerman, Iran. 9. Research Center for Environmental Determinants of Health, School of Public Health, Kermanshah Medical Sciences University, Kermanshah, Iran. 10. International Agency for Research on Cancer, Lyon, France. 11. Health Promotion Research Center, Zahedan University of Medical Sciences, Zahedan, Iran. 12. Gastrointestinal Cancer Research Center, Non-Communicable Diseases Institute, Mazandaran University of Medical Sciences, Sari, Iran. 13. Colorectal Research Center, Shiraz University of Medical Sciences, Shiraz, Iran. 14. Golestan Research Center of Gastroenterology and Hepatology, Golestan University of Medical Sciences, Gorgan, Iran. 15. Tobacco and Health Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran. 16. Cancer Research Center, Mashhad University of Medical Sciences, Mashhad, Iran. 17. Department of Urology, School of Medicine, Busher University of Medical Science, Bushehr, Iran. 18. Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran. 19. Department of Urology, Kerman University of Medical Sciences, Kerman, Iran. 20. Uro-Oncology Research Center, Tehran University of Medical Sciences, Tehran, Iran. 21. Liver and Pancreatobiliary Diseases Research Center, Digestive Diseases Research Institute, Tehran University of Medical Sciences, Tehran, Iran. 22. Social Development and Health Promotion Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran. 23. Regional Knowledge HUB for HIV/AIDS Surveillance, Research Centre for Modelling in Health, Institute for Future Studies in Health, Kerman University of Medical Sciences, Kerman, Iran. 24. Iranian National Center for Addiction Studies (INCAS), Tehran University of Medical Sciences, Tehran, Iran. 25. Digestive Oncology Research Center, Digestive Diseases Research Institute, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran. 26. Metabolic Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD, USA. 27. Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY, USA. 28. Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy. 29. Department of Biology, School of Computer, Mathematical, and Natural Sciences, Morgan State University, Baltimore, MD, USA. 30. Cancer Biology Research Center, Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran. 31. Finnish Cancer Registry, Institute for Statistical and Epidemiological Cancer Research, Helsinki, Finland.
Abstract
BACKGROUND: Bladder cancer (BC) is the 10th most common type of cancer worldwide and the fourth most common type of cancer in Iran. Opium use is considered as one of the risk factors for BC. We aim to assess the association between various parameters of opium use, which in Iran is mainly ingested or smoked in various forms, and the risk of BC. METHOD: In this multi-centre case-referent study in Iran, 717 BC cases and 3477 referents were recruited to the study from May 2017 until July 2020. Detailed histories of opium use (duration, amount, frequency) and potential confounders were collected by trained interviewers. Multivariable unconditional logistic regression models were used to measure adjusted odds ratio (OR) and 95% confidence intervals (CI). The ORs were adjusted for age, gender, place of residence and pack-years of cigarette smoking. RESULTS: Regular opium consumption was associated with an increased risk of BC (OR 3.5, 95% CI: 2.8, 4.3) compared with subjects who never used opium. Compared with continuous users, the risk decreased to one-third for those who stopped opium more than 10 years ago. The adjusted OR for those who used both crude opium (teriak) and opium juice was 7.4 (95% CI: 4.1, 13.3). There was a joint effect of opium and tobacco (OR for users of both opium and tobacco 7.7, 95% CI: 6.0, 9.7). CONCLUSIONS: Regular opium use is associated with an approximately 4-fold risk for BC. The OR decreases along with the increasing time since stopping opium use.
BACKGROUND: Bladder cancer (BC) is the 10th most common type of cancer worldwide and the fourth most common type of cancer in Iran. Opium use is considered as one of the risk factors for BC. We aim to assess the association between various parameters of opium use, which in Iran is mainly ingested or smoked in various forms, and the risk of BC. METHOD: In this multi-centre case-referent study in Iran, 717 BC cases and 3477 referents were recruited to the study from May 2017 until July 2020. Detailed histories of opium use (duration, amount, frequency) and potential confounders were collected by trained interviewers. Multivariable unconditional logistic regression models were used to measure adjusted odds ratio (OR) and 95% confidence intervals (CI). The ORs were adjusted for age, gender, place of residence and pack-years of cigarette smoking. RESULTS: Regular opium consumption was associated with an increased risk of BC (OR 3.5, 95% CI: 2.8, 4.3) compared with subjects who never used opium. Compared with continuous users, the risk decreased to one-third for those who stopped opium more than 10 years ago. The adjusted OR for those who used both crude opium (teriak) and opium juice was 7.4 (95% CI: 4.1, 13.3). There was a joint effect of opium and tobacco (OR for users of both opium and tobacco 7.7, 95% CI: 6.0, 9.7). CONCLUSIONS: Regular opium use is associated with an approximately 4-fold risk for BC. The OR decreases along with the increasing time since stopping opium use.