Population-Based Analysis Highlights Disparities in Lung Cancer Mortality in U.S.

A recent study led by Cleveland Clinic experts revealed ongoing demographic disparities in lung cancer mortality, according to data presented during the 2023 American Society of Clinical Oncology (ASCO) annual meeting.

These findings underscore the importance of targeted interventions, such as tailored health education on smoking cessation and concerted efforts to increase clinical trial participation for individuals at higher risk of worse outcomes.

“Lung cancer is the leading cause of cancer mortality in the United States, and while mortality has been decreasing overall in the last couple of decades, disparities remain among certain patient populations,” notes study author Logan Roof, MD, Chief Hematology/Oncology Fellow at Cleveland Clinic.

The Cleveland Clinic research team initiated this study to better understand the impact of demographic factors on lung cancer mortality and trends in the United States. Dr. Roof conducted this research alongside James Stevenson, MD, Vice Chair of Hematology and Medical Oncology at Cleveland Clinic, and first author Alexander J. Didier, medical student at the University of Toledo College of Medicine and Life Sciences.

Methods and findings

The Centers for Disease Control database was used to collect mortality statistics, with an underlying cause of death of lung and bronchus cancer between 1999 and 2020. Age-adjusted mortality rates (AAMR) were calculated per 100,000 deaths.

Study authors assessed age-adjusted mortality rates by several demographic factors. This included race—Hispanic, Non-Hispanic White, Non-Hispanic Black, Non-Hispanic Asian or Pacific Islander, Non-Hispanic American Indian/Native American—as well as geographic density (urban, suburban, rural), sex, age (25-44, 45-64, 65+ years) and U.S. census region.

Data showed that lung cancer led to 3,380,830 deaths between 1999 and 2020. Age-adjusted mortality rates declined during this time period, with a 42 percent decrease, according to Dr. Roof, who also reported that lung cancer is declining overall in the United States by about 2.6 percent per year.

When looking at different demographic groups, the study authors found that in 1999, men had an AAMR almost twice as high as women (76.8 vs. 40.2). However, their analysis showed that these differences became less pronounced over time. In 2020, the AAMR for men was 38.1 compared with 26.9 among women.

Findings demonstrated that non-Hispanic Black individuals had an AAMR of 49.8, with an annual decrease of -3.0%. Comparatively, non-Hispanic White individuals had an AAMR of 48.5 and an annual decrease of -2.5%.

“We also found that certain areas in the United States geographically had differences in mortality,” says Dr. Roof. “Rural populations had the highest mortality overall as compared to urban populations.”

Between 1999 and 2020, Dr. Roof and colleagues reported that rural populations experienced the highest AAMR at 52.3 as well as the slowest rate of decrease at -1.7% annually versus their urban counterparts who had an AAMR of 40.6 and an annual decrease of -3.1%.

The researchers also conducted subgroup analyses demonstrating that Non-Hispanic Black men living in rural counties had the highest mortality, with an AAMR of 60.2 and an associated decrease of -2.9% annually.

When examining geographic trends, Dr. Roof and her colleagues identified the following states with the highest lung cancer mortality: Arkansas, Kentucky and Mississippi. Conversely, the states with the lowest lung cancer mortality were Colorado, Hawaii and Utah.

Data revealed that the west had the fastest decrease in mortality at -3.1% annually, while the midwest experienced the slowest decrease at -2.0% annually.

Implications and next steps

Findings from this research confirm lung cancer mortality trends observed in other studies and highlight ongoing disparities that must be addressed. This includes targeted interventions such as tailored health education centered on smoking cessation as well as expansion of screening CT scans and telehealth platforms to improve access to care.

Another important area of focus is clinical trial enrollment. “There have been efforts nationally to increase participation of historically underrepresented populations in clinical trials,” says Dr. Roof. “One of our goals is education and sharing clinical trial information with populations who may have been underrepresented in the past, whether that be due to geographic location or certain demographic factors.”

When discussing ways to address geographic disparities in care, Dr. Stevenson notes, “In the past three to five years, we have seen Cleveland Clinic expand and partner with other regional cancer centers and healthcare facilities. This allows us to bring more resources and care to these disadvantaged areas, both in-person and via telehealth.”

“While lung cancer incidence overall as well as mortality from the disease are declining, the unfortunate reality is that it is not declining at the same rate for everyone, and there are definitely still vulnerable populations that would benefit from targeted interventions,” concludes Dr. Roof. “Dedicated efforts like the ones previously mentioned are needed to help improve care for all populations and to ensure everyone sees the same mortality benefit.”