The study examines the impact of alcohol consumption, excess body weight, human papillomavirus infection, and tobacco smoking on mortality from cancer and YLLs in Brazil, Russia, India, China, South Africa, the United Kingdom, and the United States.
Alcohol consumption, tobacco smoking, excess body weight and HPV infection caused a substantial burden of cancer mortality and YLLs in Brazil, China, India, Russia, South Africa, the UK, and US in 2020. While tobacco smoking was the predominant risk factor among all seven countries, the remaining risk factors varied in their contributions to cancer mortality, which largely reflect exposure in the population and differences in the mortality of risk factor-related cancers in each country. The study findings demonstrate the importance of cancer control efforts to reduce the burden of cancer death and YLLs due to modifiable cancer risk factors and the usefulness of YLLs to summarise disease burden.

Author

Harriet Rumgay (E-mail: rumgayh@iarc.who.int) Citadel J. Cabasag, Judith Offman, Marianna de Camargo Cancela, Anton Barchuk, Prashant Mathur, Shaoming Wang, Wenqiang Wei, Peter Sasieni, and Isabelle Soerjomatarama

Citation

Harriet Rumgay, Citadel J. Cabasag, Judith Offman, Marianna de Camargo Cancela, Anton Barchuk, Prashant Mathur, Shaoming Wang, Wenqiang Wei, Peter Sasieni, Isabelle Soerjomataram, International burden of cancer deaths and years of life lost from cancer attributable to four major risk factors: a population-based study in Brazil, Russia, India, China, South Africa, the United Kingdom, and United States, eClinicalMedicine, 2023, 102289, ISSN 2589-5370, https://doi.org/10.1016/j.eclinm.2023.102289.

Source
eClinicalMedicine (Part of The Lancet Discovery Science)
Release date
15/11/2023

International burden of cancer deaths and years of life lost from cancer attributable to four major risk factors: a population-based study in Brazil, Russia, India, China, South Africa, the United Kingdom, and United States

Research article

Summary

Background

The researchers provide a comprehensive view of the impact of alcohol consumption, tobacco smoking, excess body weight, and human papillomavirus (HPV) infection on cancer mortality and years of life lost (YLLs) in Brazil, Russia, India, China, South Africa, the United Kingdom (UK), and United States (US).

Methods

The researchers collected population attributable fractions of the four risk factors from global population-based studies and applied these to estimates of cancer deaths in 2020 to obtain potentially preventable cancer deaths and their 95% confidence intervals (CIs). Using life tables, the researchers calculated the number and age-standardised rates of YLLs (ASYR).

Findings

In Brazil, Russia, India, China, South Africa, the UK, and the US in 2020, an estimated 5.9 million YLLs from cancer were attributable to alcohol consumption, 20.8 million YLLs to tobacco smoking, 3.1 million YLLs to excess body weight, and 4.0 million YLLs to HPV infection.

The age-standardised rates of YLLs (ASYR) from cancer due to alcohol consumption was highest in China (351.4 YLLs per 100,000 population) and lowest in the US (113.5) and India (115.4).

5.9 Mn
Years of life were lost due to cancer caused by alcohol
In Brazil, Russia, India, China, South Africa, the UK, and the US in 2020, ca. 5.9 million years of life were lost due to cancer caused by alcohol – the second biggest burden after cancer due to tobacco.

For tobacco smoking, China (1159.9) had the highest ASYR followed by Russia (996.8).

For excess body weight, Russia and the US had the highest ASYRs (385.1 and 369.4, respectively).

The highest ASYR due to HPV infection was in South Africa (457.1).

ASYRs for alcohol consumption and tobacco smoking were higher among men than women, whereas women had higher ASYRs for excess body weight and HPV infection.

Interpretation

The study findings demonstrate the importance of cancer control efforts to reduce the burden of cancer death and YLLs due to modifiable cancer risk factors and promote the use of YLLs to summarise disease burden.

Research in context

Evidence before this study

Previous studies have estimated the impact of risk factors on cancer incidence and sometimes mortality but few have provided an analysis incorporating years of life lost (YLLs).

YLLs can be used to quantify the societal impact of premature deaths from diseases.

The researchers aimed to fill this gap in the literature by combining estimates of cancer deaths attributable to risk factors with measures of YLLs to provide a more comprehensive view of the impact that these different risk factors have on societies.

Added value of this study

The study examines the impact of alcohol consumption, excess body weight, human papillomavirus infection, and tobacco smoking on mortality from cancer and YLLs in Brazil, Russia, India, China, South Africa, the United Kingdom, and the United States. Disparities in the burden of YLLs between countries and between men and women largely reflect differences in risk factor exposure and cancer mortality in each population.

The study emphasises the strength of using a common methodology and data sources to compare the impact of risk factors on cancer mortality between countries. Through this study the researchers demonstrate that with publicly available data, public health advocates can construct a valuable tool to aid public health decision-making.

The researchers examined seven countries and four risk factors only, but this exercise could be undertaken for countries across the world where population data are available and should be extended to further risk factors.

Implications of all the available evidence

Primary prevention of cancer is key in reducing cancer mortality and its impact on society internationally. Together with the existing evidence, the study observations should be used to demonstrate the importance of implementing further cancer control efforts to reduce the preventable burden of cancer mortality due to modifiable cancer risk factors.

Alcohol-specific results

Cancer mortality attributable to four risk factors

In Brazil, Russia, India, China, South Africa, the UK, and the US in 2020, an estimated 326,300 cancer deaths and 5.9 million YLLs were due to alcohol consumption.

According to country, the ASYR due to alcohol consumption was highest in China (351.4 YLLs per 100,000) and lowest in the US (113.5) and India (115.4).

Overall, for both alcohol consumption and tobacco smoking, men had higher ASYRs in each country compared to women. China, India, and Russia had the largest sex differences in ASYR due to alcohol-related cancers and tobacco smoking, with ASYRs among men up to nine times higher than those among women.

The cancer types contributing the highest proportion of YLLs from cancer due to alcohol consumption varied between countries and between men and women (Fig. 2).

Fig. 2. Proportion of years of life lost from cancer deaths attributable to four risk factors: (a) alcohol consumption, (b) tobacco smoking, (c) excess body weight, (d) human papillomavirus by sex, cancer type, and country in 2020.
  • Liver cancer contributed the most YLLs among men in China (44.7%, 1.5 million of 3.3 million) and the US (40.1%, 93,300 of 232,700).
  • Colorectal cancer contributed the largest proportion of YLLs in the UK (36.5%, 24,400 of 67,000).
  • Head and neck cancers contributed more than half of YLLs from cancer due to alcohol among men in India (53.6%, 376,100 of 701,400) and more than a third in Brazil (34.5%, 60,100 of 174,200) and Russia (36.3, 77,700 of 214,100).
  • Oesophageal cancer also contributed over 40% of YLLs due to alcohol among men in China (43.3%, 1.4 million of 3.3 million) and South Africa (43.4%, 14,000 of 32,400).
  • Oesophageal cancer was also the major contributor of alcohol YLLs among women in China (48.6%, 259,900 of 534,900), South Africa (36.8%, 4600 of 12,500), and India (42.0%, 46,900 of 111,600).
  • Breast cancer was the most important contributor to alcohol-related YLLs among women in Brazil (50.0%, 21,700 of 43,300), Russia (45.4%, 37,300 of 82,200), the UK (47.1%, 13,800 of 29,300), and US (54.0%, 41,600 of 77,000).

The distribution of YLLs by cancer type varied between men and women and between countries for alcohol consumption, highlighting differences in the impact of premature death from cancer attributable to the four risk factors.

Alcohol consumption has also contributed to the elevated ASYRs the study found in China, Russia, and the UK. Alcohol use in Russia and the UK has decreased over recent decades but alcohol control efforts have recently stalled, and alcohol consumption is projected to grow in Russia by 2025. Alcohol consumption is also predicted to increase in China unless policies to reduce population alcohol use such as increases in excise taxes, restrictions on marketing, and limiting the availability of alcohol products are implemented at the highest levels.

Moreover, although a significant part of the population in Brazil abstains from alcohol use, prevalence of heavy alcohol use is on the rise.

Meaning and context

The study found stark differences in the rate of preventable YLLs between men and women in each country which varied according to risk factor. Generally, men had a higher burden of YLLs attributable to alcohol use and tobacco smoking in all seven countries, which is largely linked to higher consumption among men. This variation was much smaller in the UK and US where alcohol consumption and tobacco smoking among women have increased to similar rates to those of men.

For these four risk factors, cultural norms might have influenced differences in exposure due to how men and women’s roles in societies are perceived, including more social activities among men and stigma towards women’s use of substances associated with the male identity.

Exposure has been further impacted by commercial determinants such as the tobacco, alcohol, and food industries which have targeted gender roles to increase sales and consumption in many economically developed countries, and increasingly in low- and middle-income countries.

Cancer prevention policies should counteract these societal and commercial influences to reduce inequalities in deaths and YLLs between men and women.

Other studies such as the Global Burden of Disease (GBD) study have also estimated YLLs due to cancer attributable to major risk factors as part of their estimation of disease burden. Using the WHO world standard life table, GBD reported 32.6 million cancer YLLs due to tobacco smoking, 7.2 million due to alcohol consumption, 5.6 million due to high BMI, and 4.0 million due to unsafe sex in the seven countries of this study in 2019. The estimates made by the researchers of this study, using the WHO world standard were generally comparable to those of GBD but differences at the country and cancer type level stemmed from several sources. 

Source Website: Science Direct