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

Incidence and risk factors of pancreatic cancer during 15 years follow-up in the Golestan Cohort Study in Iran

BACKGROUND

Cancer is one of the main causes of death in the worldwide. Pancreatic Cancer (PC) is prevalent in developed and increasing in developing countries. PC is important because of its low survival rate, high fatality, and increasing incidence. Therefore, identifying risk factors to prevent its development is necessary. This study aimed to determine incidence of PC and its risk factors in the Golestan Cohort Study (GCS) in Iran.

METHOD

This study is a prospective population-based cohort study in the frame of GCS with 15 years of follow-up for PC. GCS was launched in the Golestan province of Iran with 50045 participants who were 40 to 75 years old. variables included: age, gender, education status, smoking, alcohol consumption, opium usage, type of blood group, dyslipidemia, body mass index (BMI), waist circumference (WC), family history (FH) of PC, ethnicity, and history of diabetes mellitus (DM).

RESULT

Among 50045 participants of GCS during 15 years of follow up, 100 people were diagnosed PC. PC incidence was 0.2%. Age-standardized incidence rate (ASR) of PC in the study population was 11.12 per 100,000 person-years. People with age ≥60 years were 46, in 50-59 years old group were 36, and 18 of them were <50 years (p<0.001). The smoking rate in PC group was 27% (p<0.01). Univariate model of cox regression analysis showed age 50-59, ≥60 years compared to <50 years [HR:3.006, 95%CI (1.707-5.294), p<0.001], [HR: 6.727, 95% CI (3.899-11.608), p<0.001], male gender [HR:1.541, 95%CI (1.041-2.281), p = 0.031], opium use [HR:1.436, 95% CI (0.887-2.324), p = 0.141], and smoking [HR:1.884, 95%CI (1.211-2.929), p = 0.005] were predictors for PC. In the multivariate model after adjusting, age 50-59 [HR:2.99, 95% CI (1.698-5.265), p<0.001], and ≥60 years [HR: 6.564, 95% CI (3.797-11.346), p<0.001] was the only predictor for PC.

CONCLUSION

This study revealed an incidence of PC 0.2% in GCS in Iran. Main risk factor for PC was older age.

The carcinogenicity of opium consumption: a systematic review and meta-analysis

The carcinogenicity of opium consumption was recently evaluated by a Working Group convened by the International Agency for Research on Cancer (IARC). We supplement the recent IARC evaluation by conducting an extended systematic review as well as a quantitative meta-analytic assessment of the role of opium consumption and risk for selected cancers, evaluating in detail various aspects of study quality on meta-analytic findings. We searched the published literature to identify all relevant studies on opium consumption and risk of selected cancers in humans through 31 October, 2022. Meta-relative risks (mRRs) and associated 95% confidence intervals (CIs) were estimated using random-effects models for studies of cancer of the urinary bladder, larynx, lung, oesophagus, pancreas, and stomach. Heterogeneity among studies was assessed using the I2 statistic. We assessed study quality and conducted sensitivity analyses to evaluate the impact of potential reverse causation, protopathic bias, selection bias, information bias, and confounding. In total, 2 prospective cohort studies and 33 case-control studies were included. The overall pooled mRR estimated for 'ever or regular' versus 'never' use of opium ranged from 1.50 (95% CI 1.13-1.99, I2 = 0%, 6 studies) for oesophageal cancer to 7.97 (95% CI 4.79-13.3, I2 = 62%, 7 studies) for laryngeal cancer. Analyses of cumulative opium exposure suggested greater risk of cancer associated with higher opium consumption. Findings were robust in sensitivity analyses excluding studies prone to potential methodological sources of biases and confounding. Findings support an adverse association between opium consumption and cancers of the urinary bladder, larynx, lung, oesophagus, pancreas and stomach.

Opium Use and the Risk of Liver Cancer: A Case-Control Study

Limited evidence is available to acknowledge the association between opium use and liver cancer. In a case-control study, we recruited 117 cases of primary liver cancer (PLC) and 234 age and sex-matched neighborhood controls from 2016 to 2018. We calculated odds ratios (OR) for opium use and 95% confidence intervals (95% CI), using conditional logistic regressions. Compared with non-users the adjusted OR (AOR, 95% CI) for opium use was 6.5 (95% CI, 2.87-13.44). Compared with people who had no history of use, a strong dose-response effect of opium use was observed by amount of use (AOR, 10.70; 95% CI, 3.92-28.70). Cumulative use of opium also indicated that using over 30 gr-year could increase the PLC risk dramatically (AOR, 11.0; 95% CI, 3.83-31.58). Those who used opium for more than 21 years were highly at risk of PLC (AOR, 11.66; 95% CI, 4.43-30.67). The observed associations were significant even among never tobacco smokers (including cigarette and water-pipe smoking).

PREVENTION RELEVANCE

The results of this study indicate that opium use dramatically increased the risk of liver cancer. Because opioids are increasing for medical and non-medical use globally; accordingly, severe health consequences such as liver cancer have to be investigated widely.

Opium consumption and pancreatic cancer: A meta-analysis

Pancreatic cancer represents a serious public health problem worldwide. Due to its high mortality, efforts on identifying risk factors are very important since only a few risk-related factors have been well established. The present study aimed to address this knowledge gap by estimating the risk of pancreatic cancer associated with opium use. We performed a thorough literature search of PubMed, Web of Science and Scopus, which yielded 3 case-control and 1 cohort study which were included in the analysis. A meta-analysis was conducted using the DerSimonian and Laird inverse-variance approach as the random effects method. The pooled risk ratio for pancreatic cancer in opium users was significantly increased (RR=1.98, 95 % CI 1.33-2.96, p = 0.0008) compared to never users. Subgroup analyses identified a significantly increased risk for pancreatic cancer in men (RR=1.74, 95 % CI 1.22-2.47, p = 0.002), in persons who consumed both raw teriak and refined shireh opium (RR=4.21, 95 % 1.27-13.93, p = 0.02) and in persons who smoked opium (RR=4.21, 95 % 1.27-13.93, p = 0.02). The findings of this study will help in efforts aimed at prevention of pancreatic cancer. Still, further epidemiological research is necessary.