The links between tobacco use and cancer shouldn’t come as a big surprise to most Labroots readers. Tobacco use, along with alcohol consumption, excess body weight, and human papillomavirus (HPV) infection, all contribute significantly to the international cancer burden. In other words, these four risk factors lead to cancer deaths and thus carry a heavy burden on global health.
A new study published in the journal eClinicalMedicine looked at the impact of four known risk factors for cancer (alcohol consumption, tobacco smoking, excess body weight, and human HPV infection on cancer mortality and years of life lost (YLLs).
Epidemiologists use YLL to describe the number of years forfeited when someone dies of cancer, based on the life expectancy of an individual. This type of statistic weighs the death of younger individuals more heavily than younger individuals by accounting for premature mortality. For example, an individual who dies at age 80 will have a lower YLL than an individual who dies at 30.
The researchers estimated how the four risk factors, as assessed in global population-based studies, impacted cancer deaths in 2020. All four risk factors considered are “modifiable risk factors,” meaning that they describe behaviors that, if changed, would reduce the associated risk. The process allowed the research team to determine the percentage of these cancer deaths that could be prevented if behaviors were modified.
The study considered the cancer burden attributed to these factors in seven countries (Brazil, Russia, India, China, South Africa, the United Kingdom, and the United States. In 2020, these seven nations experienced 326,200 cancer deaths attributed to alcohol consumption, 1.3 million cancer deaths attributed to tobacco use, 208,000 cancer deaths attributed to excess body weight, and 190,400 cancer deaths attributed to HPV infections. In total, the study estimates over 2 million lives, across seven countries, that could be saved by altering modifiable behaviors!
In 2020, an estimated 33.8 million YLL were attributed to the four modifiable risk factors. These YLL included 5.9 million YLL due to alcohol, 20.8 YLL due to smoking, 3.1 YLL due to excess body weight, and 5 YLL due to HPV infection.
The study reiterates the importance of implementing effective cancer prevention and treatment strategies. Further, the authors suggest that this study demonstrates the feasibility of using YLL to summarize cancer burden in other studies. YLL considers both the number of cancer deaths and the burden of premature deaths from people dying earlier than their life expectancy, providing valuable information for cancer research.