Study Documents Rise in Global Lung Cancer Rates Over 30 Years

Results of an epidemiological study that spanned 30 years and 204 countries concluded lung cancer remains a major public health issue globally, prompting authors to call for implementation of tailored scientific and effective interventions. Findings were published in BMC Public Health.

In 2020, a total of 1,796,144 lung cancer deaths were reported, accounting for around 18% of all global cancer deaths, researchers explained. In an effort to better classify and understand prevalence, incidence, and years lived with disability (YLDs), investigators assessed data from the Global Burden of Disease Study (GBD) 2019. They also evaluated the spatiotemporal dynamics of the disease by looking at global, regional, and national trends between 1990 and 2019.

The GBD 2019 includes information from all World Health Organization (WHO) member states, in addition to “a comprehensive assessment on 87 risk factors, 369 diseases and injuries from 1990 to 2019 in 204 countries and territories.”

The countries and territories were grouped into 21 GBD regions and the globe into 5 regions based on sociodemographic index (SDI).

Data showed that in 2019, 3,212,307 individuals had lung cancer, marking a 1.32-fold increase from 1990 (1,385,579), with increases also seen in the age-standardized prevalence rate (ASPR) throughout the same time period.

Additional analyses revealed:

• Globally, the age-standardized rates (ASR) of lung cancer prevalence, incidence and YLDs in 2019 were 38.84/100,000 persons, 27.66/100,000 persons, and 6.62/100,000 persons, respectively.
• Over the past 30 years, the ASR of incidence (estimated annual percentage change [EAPC] = –0.09) decreased, although those of prevalence (EAPC = 0.51) and YLDs (EAPC = 0.03) increased.
• The global prevalence counts were greater in men than women at all age groups and increased with age, peaking in the group aged 65 to 69 years for both sexes.
• The increase in incidence was mainly attributed to population aging.
• For YLDs, EAPC was negatively correlated with the human development index (P = .0008) and ASR (P < .0001) in 1990 across nation-level units.

Low SDI nations reported the lowest absolute number and ASP of lung cancer prevalence in 2019, while the highest absolute number and ASR were reported in high SDI nations, the authors wrote.

Regional assessments found:

• The number of patients with lung cancer increased in all SDI regions, with the largest increase in middle SDI regions (2.52-fold), while the ASPR only decreased in high-middle SDI regions (EAPC = -0.49) from 1990 to 2019.
• Among 21 GBD regions, East Asia (1,163,481), high-income North America (499,571) and Western Europe (466,299) exhibited the highest prevalent cases in 2019.
• The highest ASPR was observed in high-income North America (80.37/100,000 persons), followed by high-income Asia Pacific (74.32/100,000 persons), Australasia (58.50/100,000 persons) and Western Europe (57.24/100,000 persons).
• Over the past 30 years, the most significant increase in lung cancer patients (3.03-fold) was observed in East Asia, with the highest EAPC of ASPR (1.97) in Southern Latin America.

Although Monaco, Greenland, and Canada had the largest ASPR reported, and China, the United States, and Japan reported the greatest prevalent cases in 2019, the number of patients with lung cancer increased in 95.59% of all countries surveyed, with an 8.43-fold increase seen in the United Arab Emirates and a 7.37-fold increase in Qatar.

The lack of decreasing global trends could be due to a myriad of factors, the authors noted, including high consumption of tobacco in developing countries, ramifications of environmental deterioration and ecological destruction leading to more outdoor air pollution, and increased exposure to indoor hazardous conditions elevated from industrialization and urbanization.

“As per WHO estimates, more than 107,000 people die each year from lung cancer, mesothelioma, and asbestosis resulting from exposure to asbestos in the workplace,” researchers explained.

However, advancements in treatment and surgical techniques over the past 30 years have contributed to improved mortality rates.

Sex differences in lung cancer rates are mainly attributed to differences in smoking, occupational hazards, particulate matter pollution and exposure to carcinogens, while men also have higher blood sugar levels than women, resulting in a disproportionate cancer risk in this population.

Disease burden was not assessed in countries lacking organized architecture to register, record, and report diseases, marking a limitation to the study. Data also did not differentiate between the burden of small cell and non–small cell lung cancer.

“Differences in geographic and country-specific population characteristics emphasize the need for targeted strategies to reduce the lung cancer burden,” the authors concluded.

Reference

Chen X, Mo S, Yi B. The spatiotemporal dynamics of lung cancer: 30-year trends of epidemiology across 204 countries and territories. BMC Public Health. Published online May 16, 2022. doi:10.1186/s12889-022-13281-y