Cancer Mortality Down 20 Percent Since 1980, but Regional Disparities Persist

According to a population-based modeling study published in JAMA, cancer mortality rates decreased by 20.1 percent (95% CI 18.2-21.4) between 1980 and 2014 – down from 240.2 deaths per 100,000 person-years in 1980 to 192 deaths per 100,000 person-years in 2014.

The rate varied across the country, though. For example, in Summit County, Colorado, cancer mortality in 1980 was 130.6 deaths per 100,000 person-years, dropping to 70.7 deaths in 2014. In North Slope Borough, Alaska, however, the cancer mortality rate rose from 386.9 deaths per 100,000 person-years in 1980 to 503.1 deaths in 2014.

“Such significant disparities among U.S. counties is unacceptable,” Ali H. Mokdad, PhD, from the Institute for Health Metrics and Evaluation at the University of Washington, Seattle, and authors wrote. “Every person should have access to early screenings for cancer, as well as adequate treatment.”

Dr. Mokdad and authors analyzed de-identified death records from the National Center for Health Statistics (NCHS) and population data from the Census Bureau, NCHS, and the Human Mortality Database. Deaths and population were analyzed by county, age group (in 5-year intervals), sex, year, and cause of death (when applicable). Validated models were used to estimate county-level mortality rates from 29 cancers, including Hodgkin lymphoma, non-Hodgkin lymphoma, multiple myeloma, and leukemia.

The highest mortality rates were seen in several areas of the southern United States (including Kentucky, West Virginia, Alabama, and areas along the Mississippi River) and Western Alaska. Overall, there were statistically significant increases in cancer mortality between 1980 and 2014 in 160 U.S. counties, with the highest rates of increase observed in Kentucky and scattered throughout the South.

The researchers cited several potential explanations for these geographic disparities. First, cancer incidence could be high due to risk factor profiles and poor prevention and screening programs. Second, late cancer detection due to lack of screening, lack of awareness in the population and health-care clinicians, and poor access to health care could affect outcomes. Lastly, obesity is a major risk factor for cancer, and rates of overweight and obesity have increased steadily in the United States, with higher rates of obesity documented in southern parts of the country.

Source: Mokdad AH, Dwyer-Lindgren L, Fitzmaurice C, et al. Trends and patterns of disparities in cancer mortality among US counties, 1980-2014. JAMA. 2017;317:388-406.