(CNN) — Globally, nearly half of cancer deaths can be attributed to preventable risk factors, including the top three risks: smoking, drinking too much alcohol or having a high body mass index, a new study suggests.
“To our knowledge, this study represents the largest effort to date to determine the global burden of cancer attributable to risk factors, and contributes to a growing body of evidence aimed at estimating the burden attributable to risk for specific cancers at the nationally, internationally and globally,” Dr. Chris Murray, director of the Institute for Health Metrics and Evaluation at the University of Washington, and colleagues wrote in the study.
The paper, funded by the Bill and Melinda Gates Foundation, analyzed the relationship between risk factors and cancer, the second leading cause of death worldwide, using data from the project Global Burden of Disease from the Institute for Health Metrics and Evaluation.
The project collects and analyzes global data on death and disability. Murray and her colleagues focused on cancer deaths and disability between 2010 and 2019 in 204 countries, examining 23 cancer types and 34 risk factors.
The leading cancers in terms of deaths attributable to risk factors globally in 2019 were cancers of the trachea, bronchus and lung for both men and women, the researchers found.
The data also showed that cancer deaths attributable to risk factors are on the rise, rising worldwide by 20.4% between 2010 and 2019. Globally, in 2019, the five leading regions in terms of death rates attributable to risk factors were central Europe, America, southern Latin America, and western Europe.
“These findings highlight that a substantial proportion of the global cancer burden has potential for prevention through interventions aimed at reducing exposure to known cancer risk factors, but also that a large proportion of the cancer burden could not be preventable by controlling for currently estimated risk factors,” the researchers wrote. “Therefore, efforts to reduce cancer risk must be combined with comprehensive cancer control strategies that include efforts to support early diagnosis and effective treatment.”
The new study “clearly delineates” the importance of primary cancer prevention and “the growing number of obesity-related cancers clearly demands our attention,” Dr. William Dahut, chief scientific officer of the Society, wrote in an email to CNN. Cancer Center, which was not involved in the new study.
“Changing behavior could lead to millions more lives being saved, greatly dwarfing the impact of any drug that has ever been approved,” he wrote, adding: “Tobacco’s continued impact despite approximately 65 years of association with cancer is still very problematic.
Although tobacco use in the United States is lower than in other countries, tobacco-related cancer deaths remain a significant problem, disproportionately affecting certain states, Dahut wrote.
A separate study, published earlier this month in the International Journal of Cancer, found that the estimated proportion of cancer deaths in 2019 attributable to smoking in adults ages 25 to 79 ranged from 16.5% in Utah to 37.8% in Kentucky. The total estimated loss of income due to cancer deaths attributable to smoking ranged from $32.2 million in Wyoming to $1.6 billion in California.
“Furthermore, it is no secret that alcohol consumption, as well as the dramatic increase in mean BMI, will lead to a significant number of preventable cancer deaths,” Dahut added. “Finally, cancer screening is particularly important in those most at risk as we move toward a world where screening is precision-based and adaptive.”
In an editorial published alongside the new study in The Lancet, Dr. Diana Safarti and Jason Gurney of the Te Aho o Te Kahu Cancer Control Agency in New Zealand wrote that preventable risk factors associated with cancer tend to to be modeled according to poverty.
“Poverty influences the environments in which people live, and those environments shape the lifestyle choices people can make. Action to prevent cancer requires a concerted effort within and outside the health sector.” This action includes specific policies focused on reducing exposure to cancer-causing risk factors, such as tobacco and alcohol use, and access to vaccines that prevent cancer-causing infections, such as hepatitis B and HPV,” they wrote. Safariti and Gurney.
“Primary prevention of cancer through the eradication or mitigation of modifiable risk factors is our best hope of reducing the future burden of cancer,” they wrote. “Reducing this burden will improve health and well-being, and alleviate the combined effects on humans and fiscal resource pressure within cancer services and the broader health sector.”