Is opium use associated with an increased risk of lung cancer? A case-control study.

BACKGROUND: In recent years, lung cancer (LC) incidence has increased in Iran. The use of opium and its derivatives (O&D) has increased as well. This study aimed to investigate the association between the use of O&D and LC incidence. METHODS: In this case-control study conducted in Kerman, Iran; 140 patients with lung cancer and 280 healthy controls matched by age, sex, and place of residence were included. Data, including O&D use, cigarette smoking, alcohol use, and diet, were collected using a structured questionnaire. The relation between the use of O&D and LC was evaluated using conditional logistic regression adjusted for tobacco smoking, education, daily intake of fruit, vegetables, red meat, and hydrogenated fats. RESULTS: Opium ever-use was associated with an increased risk of LC (Adjusted Odds Ratio (AOR) =5.95, 95% CI: 1.87-18.92). Participants were divided into low and high use groups based on the median of opium use in the control group. A significant dose-response relation was observed between the amount of daily O&D use and LC; and the relation was stronger in high users (AOR low users = 3.81% CI: 1.13-12.77 and OR high users = 9.36, 95% CI: 2.05-42.72). Also, LC was higher among participants starting the use of O&D at younger ages (≤ 41 years old vs never users AOR = 8.64, 95% CI: 1.90-39.18) compared to those who started at an older age (> 41 years old vs never users, AOR = 4.71, 95% CI: 1.38-16.08). The association between opium, and lung cancer among non-smokers was OR: 6.50 (95% CI: 2.89 to 14.64). CONCLUSION: The results of this study show that opium use is probably a dose related risk factor for lung cancer.

Opium Use and Head and Neck Cancers: A Matched Case-Control Study in Iran.

BACKGROUND: Head and Neck (H and N) cancers include malignant tumors of the nasal cavity, pharynx, paranasal sinuses, oral cavity, larynx and salivary glands. Opium use might be related to these cancers. The aim of this study was to investigate the relation between Opium and its Derivatives (O and D) use and the incidence of H and N cancers. METHODS: In this case-control study conducted in Kerman, 140 patients with HandN cancers and 280 healthy controls (matched for age, gender, and place of residence) were included. Information about their use of O and D, cigarette smoking, alcohol and diet were collected using a structured questionnaire. Conditional logistic regression was used to investigate the relation between variables. RESULTS: The use of opioids was associated with an increased risk of H and N cancers (Adjusted OR: 8.13; CI: 4.08-16.2). A significant dose-response relation between O and D use was observed, with high use Adjusted OR=8.91; 95% CI: 4.03-19.65 and low use Adjusted OR=6.52; 95% CI: 3.18- 13.36. This dose-response association was stronger in patients with laryngeal cancer and opioids use, with high use Adjusted OR = 11.17; 95% CI=4.48-28.09 and low use Adjusted OR = 9.46; 95% CI= 3.97- 22.52. CONCLUSION: The results show that opium use can be considered as an important risk factor for H and N cancers. Also in Iran, opium seems to play a more important role than cigarette smoking.

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). CONCLUSION: The results of this study showed that opium consumption can be a strong risk factor for UGI cancers in Iran.