Population attributable proportion and number of cancer cases attributed to potentially modifiable risk factors in Iran in 2020

Potential impact of controlling opium use prevalence on future cancer incidence in Iran

Background

The International Agency for Research on Cancer (IARC) recently classified opium consumption as carcinogenic to humans. This study aimed to estimate the potential reduction in incident cancers by 2035 in Iran, which accounts for 42% of global opium consumption, through decreasing opium use prevalence.

Methods

The population attributable fraction (PAF) of opium-related cancers was projected using national cancer incidence, age- and gender-specific opium use prevalence, relative cancer risks associated with opium use, and annual percentage changes in cancer incidence rates in Iran. Opium-related cancers were defined based on IARC monographs as cancers of lung, larynx, bladder, esophagus, stomach, pancreas, and pharynx. The number of preventable cancer cases under different opium prevalence scenarios was determined by subtracting attributable cases in each year based on current prevalence from those in alternative scenarios.

Findings

By 2035, an estimated 3,001,421 new cancer cases are expected in Iran, with 904,013 (30.1%) occurring in opium-related sites. Maintaining the current opium prevalence (5.6%) is projected to cause 111,130 new cancer cases (3.7% of all cancers, 12.3% of opium-related). A 10%, 30%, and 50% reduction in opium prevalence could prevent 9,016, 28,161, and 49,006 total incident cancers by 2035 in Iran, respectively. Reducing opium use prevalence by 10%-50% is projected to have the highest impact on lung cancer (prevention of 2,946-15,831 cases), stomach cancer (prevention of 2,404-12,593 cases), and bladder cancer (prevention of 1,725-9,520 cases).

Interpretation

Our results highlight the significant benefits that can be achieved through effective cancer prevention policies targeting opium use in Iran. Neglecting this risk factor is estimated to pose a significant burden on cancer incidence in the next decade in this population.

Funding

None.

Survey of awareness and beliefs about cancer (ABC) in Tehran Province, Iran

INTRODUCTION

Knowledge, attitudes, and practices are essential measures for planning and evaluating cancer control programs. Little is known about these in Iran.

METHODS

We conducted a population-based interview survey of adults aged 30-70 using the Farsi version of the Awareness and Beliefs about Cancer questionnaire in the capital province of Tehran, Iran, 2019. We calculated weighted estimates of levels of cancer knowledge, attitudes, and practices to allow for different selection probabilities and nonresponse. We used multivariate logistic regression to understand demographic factors associated with bowel, cervix, and breast screening practices.

RESULTS

We interviewed 736 men and 744 women. The mean number of recalled cancer warning signs was less than one; 57.7% could not recall any cancer warning signs. Participants recognized 5.6 out of 11 early cancer warning signs and 8.8 of 13 cancer risk factors. Most (82.7%) did not know that HPV infection was a cancer risk factor. Approximately, half had negative attitudes towards cancer treatment, but over 80% had positive attitudes towards the effectiveness of screening for improving survival. Colorectal, breast, and cervical screening rates were 24%, 42%, and 49%, respectively. Higher socioeconomic status increased the odds of taking up screening for cancer. Women aged 60-70 were less likely to report taking up breast and cervical screening than younger women.

DISCUSSION

The Iranian population has poor awareness and negative attitudes about cancer, and participation in screening programs is low. Public awareness and early detection of cancer should be promoted in Iran.

Time trends of 16 modifiable risk factors on the burden of major cancers among the Chinese population

The cancer burden in China is increasing. We aimed to assess the time trends in the prevalence of 16 modifiable risk factors involved in lifestyle, diet, infection, and air pollution between 1997 and 2025 based on the China Health and Nutrition Survey, the Global Burden of Disease website, and publically available studies. The population attributable fraction (PAF) and its 95% uncertainty interval (UI) from 2007 to 2035 were calculated to quantify the attributable cancer burden in major 12 anatomic sites using the comparative risk assessment method, considering a 10-year lag effect. As a result, 1,559,476 cancer cases (PAF = 54.1%, 95% UI: 36.8%-65.8%) from the 12 anatomic sites were attributable to these modifiable risk factors in 2007, with lung, liver, and gastric cancer raging the top three. It was predicted that by 2035, the attributable cancer cases would reach 1,680,098 (PAF = 44.2%, 95% UI: 29.1%-55.5%), with the top three of lung, liver, and colorectal cancer. Smoking, physical inactivity, insufficient fruit consumption, HBV infection, and Helicobacter pylori infection were the most attributable risk factors in 2007, contributing to 480,352, 233,684, 215,009, 214,455, and 187,305 associated cancer cases, respectively. In 2035, the leading factors for cancer would be smoking, physical inactivity, insufficient fruit intake, HPV infection, and HBV infection, resulting in 427,445, 424,327, 185,144, 156,535, and 154,368 cancer cases, respectively. Intervention strategies should be swiftly established and dynamically altered in response to risk factors like smoking, physical inactivity, poor fruit intake, and infectious factors that may cause a high cancer burden in the Chinese population.

A decade of tobacco control efforts: Implications for tobacco smoking prevalence in Eastern Mediterranean countries

BACKGROUND AND OBJECTIVES

This study aimed to assess the association between the 10-year implementation of tobacco control policies, cigarette affordability index and changes in tobacco smoking prevalence across Eastern Mediterranean (EMR) countries.

MATERIALS AND METHODS

An ecologic study was conducted using EMR countries as the analytical unit. Data from three sources were utilized: the MPOWER scale to measure tobacco control policy implementation (2010-2020), the tobacco affordability index (expressed as a percentage of GDP per capita required to purchase 2000 cigarettes, from 2010 to 2020), and national tobacco smoking prevalence data for EMR countries (2010-2023). Linear Fixed-effect regression was employed to investigate associations between changes in MPOWER scores, the cigarette affordability index, and alterations in tobacco prevalence over a decade.

RESULTS

Statistically significant inverse associations were observed between changes in MPOWER scores and tobacco smoking prevalence among both men and women in EMR countries (P-value<0.05). Each unit increase in MPOWER score corresponded to a 0.26% reduction in tobacco prevalence among men and a 0.12% reduction among women. The regression model revealed that each unit increase in the cigarette affordability index was linked to a 0.9% decrease in tobacco smoking prevalence across EMR countries (P-value<0.05). Furthermore, even after adjusting for multiple confounders, significant inverse associations were noted between tobacco monitoring (β = -0.41), health warning (β = -0.45), and changes in tobacco smoking prevalence (P-value<0.05).

CONCLUSION

This study underscored the effectiveness of enhancing the implementation of tobacco control policies and increasing the cigarette affordability index as preventive measures to reduce tobacco smoking prevalence in EMR countries over the past decade.