Global Study on Cancer Burden: Asbestos Exposure Remains a Leading Risk Factor
Occupational exposure to asbestos is among the top risk factors contributing to the burden of cancer worldwide, according to research published last month in The Lancet. The research is based on the 2019 iteration of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD), a long-running project led by the University of Washington that provides estimates of global health for causes of death and disability and their associated risk factors.
The GBD uses disability-adjusted life years, or DALYs, to estimate the burden of cancer attributable to more than 80 risk factors. These factors are grouped into three main categories: behavioral, metabolic, and environmental and occupational. The metrics that comprise DALYs are years of life lost (YLLs) due to premature mortality and years of healthy life lost due to disability (YLDs). The paper also describes differences in cancer burden through the lens of the GBD socio-demographic index, a measure of a country’s development that incorporates rankings of income per capita, educational attainment, and fertility rates.
According to the 2019 iteration of GBD, the leading age-adjusted risk factors contributing to worldwide cancer burden in 2019 were almost identical to those in 2010. Occupational exposure to asbestos ranked seventh in both years, with 61.1 DALYs per 100,000 person years in 2010 and 50.9 DALYs per 100,000 person years in 2019. The percentage change of 16.7 DALYs for occupational asbestos exposure was the largest drop among the top ten risk factors but not enough to change its position in the rankings.
The top risk factor was smoking, with 774.1 DALYs per 100,000 person years in 2010 and 677.3 DALYs per 100,000 person years in 2019. Other top risk factors were alcohol use, high body-mass index, and unsafe sex. Ambient particulate matter pollution ranked sixth, with 86.3 DALYs per 100,000 person years in 2010 and 84.2 DALYs per 100,000 person years in 2019.
Supplemental material provided by the authors further breaks down the 2019 GBD data by gender and by SDI quintiles. For men in countries in the top SDI quintile, occupational exposure to asbestos is the third leading cancer risk factor, with an age-adjusted rate of 215.6 DALYs per 100,000 person years in 2019. For men in countries with a high-middle SDI rating, occupational exposure to asbestos was the sixth leading risk factor for cancer in 2019. Occupational asbestos exposure does not appear among the top 10 risk factors for men or women in countries whose SDI rating is in the middle quintile or lower.
The paper “The Global Burden of Cancer Attributable to Risk Factors, 2010–19: A Systematic Analysis for the Global Burden of Disease Study 2019,” including its supplemental materials, is an open-access publication. More information about the GBD is available from The Lancet.