The “Belt and Road” (“B&R”) Initiative refers to the “Silk Road Economic Belt” and the “21st Century Maritime Silk Road”, which was first proposed by China in 2013. “B&R” countries run through Eurasia, connecting the Asia Pacific Economic Circle in the east and the European Economic Circle in the west (1). “B&R” Initiative can fully rely on the existing bilateral and multilateral mechanisms between China and relevant countries and leverage existing and effective regional cooperation platforms. Health crises are cross-border issues that require collective action to address (2, 3). In 2017, the Chinese government proposed the “Health Silk Road” (HSR) initiative to strengthen global health cooperation. “B&R” health exchange and cooperation helps to share successful experiences in the medical and health field. HSR initiative can promote cooperation in health, build a strong and resilient health system for transnational cooperation, and jointly build a “community of human health” in order to deal with disease epidemics.

Lung cancer is one of the main causes of new cancer cases and cancer-related deaths worldwide (4). In the past two decades, significant improvements have been made in understanding the biology and targeted therapy in lung cancer and the application of immune checkpoint inhibitors (ICIs), which have changed the prognosis of many patients (5). In terms of disability-adjusted life years (DALYs), the disease burden is evolving to be dominated by the years lived with disability (YLDs) (6). YLDs measure the amount of time that people lose to illnesses and injuries that do not cause death but reduce health. These areas are becoming hot topics for measuring and improving health outcomes due to transitions in aging populations and mortality in different countries.

Currently, “B&R” member countries are facing varying degrees of lung cancer threat. It is crucial to have comparable and comprehensive analysis and assessment of lung cancer incidence, mortality, disease burden, and long-term trends in China and its partner countries in order to improve public health and the success of the organizations. However, little is known about the status and extent of lung cancer in the 66 countries under the “B&R” Initiative. Our objective is to estimate the burden and trends of lung cancer from 1990 to 2019 through this study, providing a basis for formulating disease prevention and control policies and building a “community of human health” by strengthening health industry cooperation among the “B&R” countries.

With an estimated 1.79 million deaths per year, lung cancer is one of the leading causes of cancer-related deaths (5). Smoking, poor diet, lack of exercise, genetic factors, air pollution, and occupational exposure are all risk factors for cancer (13). Smoking is an important risk factor for increasing cancer risk (14). Cigarettes contain polycyclic aromatic hydrocarbons and nitrosamines. Nicotine is an addictive substance, so it leads to frequent use among smokers, and therefore, lung cancer is more common among them (15, 16). In the last decade, the age-standardized incidence rate in high-socio-demographic index countries has been decreasing due to tobacco control (17). We found that the incidence, prevalence, and YLDs increased the fastest in China from 1990 to 2019, and the age-standardized incidence, prevalence, mortality, and DALYs showed an upward trend in China, South Asia, North Africa, and the Middle East, which may be related to a large number of smokers in these countries.

Our study found significant differences in the trend of age-standardized YLDs between genders. A downward trend of the AAPC values of age-standardized YLD rate in men was shown in the “B&R” countries. For women, the upward change trend of YLDs was observed in most countries. The global incidence of lung cancer in men is declining twice as fast as in women (5). The age-standardized incidence rates of lung cancer among women are predicted to increase before 2035 and are expected to peak after the 2020s, while those among men are expected to decrease in almost all countries (18). The mortality of cancers due to smoking has substantially increased among women in most countries of the North Africa and Middle East region (19). These studies all suggest that the “B&R” and even countries around the world need to strengthen the publicity and education of female smoking cessation and attach importance to physical examination and lung screening, which will help control the incidence rate and mortality of female lung cancer.

The increase in life expectancy has led to a greater global burden of diseases. Global population aging is the principal medical and social demographic problem worldwide. In the Non-Organisation for Economic Co-operation and Development countries, the fastest-aging countries are Saudi Arabia, Brazil, and China (20). Since 2000, China has gradually entered an aging society, the aging in China has not been alleviated but has gradually increased recently, and the burden of lung cancer on elderly patients is also increasing (21). In the “B&R” member countries, the age-standardized YLDs in most countries showed an upward trend with the increase of age, and the highest AAPC value of the age-standardized YLDs in 1990–2019 was in adults aged 75 years or older. A satisfactory and appropriate understanding of the health problems of older people caused by aging is a common challenge in the world. The goal vision is to establish a world where everyone has the chance to live a healthy and long life (20). This requires close cooperation between multiple sectors and departments in the “B&R” member countries to promote healthy aging.

In recent decades, countries within the Middle East have faced social, political, and financial instability brought about by war. These conflicts have directly led to a significant decline in the overall level of local medical services and a shortage of professional experts, seriously affecting the provision of cancer diagnosis services. The cancer patients in these areas cannot be diagnosed early and cannot receive effective healthcare (22, 23). In addition, the use of depleted uranium and white phosphorus bombs in wars may cause environmental pollution and even cancer (24). Therefore, many cancer patients must bear the cost of traveling to neighboring countries in order to receive medical services. Our study also found that from 1990 to 2019, the AAPC of age-standardized incidence rate, morbidity, mortality, and DALYs showed an upward trend in most countries in the Middle East. It is important to alleviate the shortage of medical services for these countries through the “B&R” Initiative.

With a deeper understanding of the biology of lung cancer, many advances have been made in the treatment of lung cancer, such as minimally invasive techniques, stereotactic ablative radiotherapy, targeted therapies, and ICIs (25). New therapies have benefited patients and reduced the burden of disease. However, due to various reasons such as economic development and healthcare systems, countries have varying opportunities to access drugs and healthcare (5). In low-income countries, new lung cancer cases and mortality continue to increase, which may be related to limited access to healthcare and outdated treatment methods in these countries (5). By implementing large-scale infrastructure construction and trade facilitation, poor and low-income countries can return to the mainstream of global development from a state of global marginalization, thereby providing bright prospects for comprehensive and long-term economic growth in the “B&R” member countries. In addition, the medical field should also be highly valued. The exchange of medical knowledge and experience among medical institutions in the “B&R” countries should be continuously promoted so that medical technology and health services will be extended from higher-level countries to lower-level ones, thus improving the medical level of each country and benefiting low-income people.

YLDs can reflect the amount of time lived in states of less than good health due to a specific disease or injury and are calculated as the prevalence of a sequela of any given cause multiplied by the average duration until death or remission and by the disability weight for that sequela. The YLDs are the sum of each of the sequelae associated with the disease or injury (26, 27). YLL refers to the loss of life caused by early death. Although YLDs and YLLs can reflect the burden on society, YLDs are more likely to be affected by diseases and injuries in their lives. Reducing the burden of disease involves not only prolonging the survival period of patients but also improving the quality of life of patients. The interventions required to reduce the causes of death may differ from those needed to reduce risk factors and disability rates for disease burden. This is why we chose to calculate YLDs in this study.

Globally, from 2010 to 2019, the number of lung cancer increased by 23.3%, and the age-standardized incidence rates decreased by 7.4% in men and increased by 0.9% in women (4). Compared to the USA and UK, China had lower incidence but higher cancer mortality and DALYs (28). All the age-standardized incidences had a decreasing trend in men and an increasing trend in women from 1990 to 2019 in the North Africa and Middle East region. Over 80% of DALYs could be decreased by controlling tobacco use (23). The number of new cases is predicted to increase by 50.19% from 2010 to 2035. When stratified by geographic region, the most rapid increases were predicted in Eastern Asia (79.00% for men and 140.05% for women) (18). We found that in the “B&R” countries, especially in middle SDI regions, DALYs due to all risk factors showed an upward trend, while globally, DALYs had a downward trend.

Unlike previous lung cancer burden studies based on GBD data, this study focuses on the “B&R” countries proposed by China, the world’s second-largest economy, under the global community of shared future strategy. It not only describes the changes in disease burden in a specific region or globally but also provides targeted data support for how countries with significant differences in social demographic indices but strong political and economic connections can formulate policies to reduce the burden of lung cancer. Preventive measures such as smoking control interventions and air quality management should be prioritized in low and middle SDI regions. Our research also suggested that we should pay more attention to female lung cancer patients. For women, the upward trend of YLDs was observed in the “B&R” countries, and it may continue to rise in the future (18). By studying the continuous transformation of epidemiology in the “B&R” countries, the necessity of resource redistribution and improvement of lung cancer control measures is highlighted.

This study also has several limitations. First, GBD 2019 has inherent limitations that are applicable to this study. Second, the GBD database lacks lung cancer’s pathological staging and classification. In the future, the “B&R” countries can use economic development as a link to drive the construction of information-based disease monitoring systems, providing sufficient support for the estimation of disease burden and policy adjustments.

In summary, the overall burden of lung cancer in the “B&R” countries is still huge, especially in China, South Asia, North Africa, and the Middle East. There are significant differences between genders and ages. The lung cancer prevention and treatment policies in women and adults aged 75 years or older need to be improved. With the background of the health “B&R” Initiative, multi-country cooperation and experience sharing will play an important role in jointly facing the challenges caused by lung cancer and promoting the positive development of healthcare in all member countries.

The original contributions presented in the study are included in the article/ Supplementary Material . Further inquiries can be directed to the corresponding author.

XL conceived and designed the study. ZZhu, WY, LZ, WJ, BC,QW, XC, SY, and ZZhang analyzed the data. ZZhu, XL, and YD provided significant advice and consultation. WY and XL wrote the manuscript. All authors contributed to the article and approved the submitted version.