Head and Neck Cancer Mortality in the Appalachian Region

Abstract

This cross-sectional study analyzes whether different head and neck cancer mortality trends exist among the Appalachian population.

A recent study by Balanchivadze et al¹ demonstrated that rural areas in the US had higher head and neck cancer (HNC) mortality rates and slower rate improvement than urban areas despite advances in HNC care. One factor not addressed, however, was the heterogeneity among rural populations. The Appalachian region—designated as a special population by the National Cancer Institute—spans 423 counties across 13 eastern states and includes approximately one-fifth of all US rural residents.² We analyzed whether different HNC mortality trends existed among the Appalachian population.

Methods

We used the Appalachian Regional Commission to identify counties belonging to the Appalachian region and specific Appalachian subregions.² We obtained HNC mortality rates from the Centers for Disease Control and Prevention WONDER (Wide-Ranging Online Data for Epidemiologic Research) underlying cause of death, 1999-2020, dataset.³ HNC deaths were defined as those with International Classification of Diseases, Tenth Revision, codes C00 to C14, C30 to C32, and C73. Five-year rates from 2016 to 2020 were calculated and age-adjusted to the 2000 US standard population. Annual rates from 1999 to 2020 were collected for trend analysis. Data were extracted for nonmetropolitan/rural areas using 2013 urbanization codes. Average annual percentage changes (AAPCs) in age-adjusted mortality rates (AAMRs) were estimated using Joinpoint software, version 5.2.0 (National Cancer Institute). All statistical tests used P < .05 and were 2-sided. Data were analyzed using R, version 4.4.1 (R Project for Statistical Computing). The institutional review board at the University of Kentucky waived need for approval and patient informed consent because data used were deidentified. We followed the STROBE reporting guidelines.

Results

From 2016 to 2020, there was a statistically significant higher AAMR for HNC in the Appalachian region (4.62 [95% CI, 4.52-4.72] per 100 000 population) than in non-Appalachia (4.03 [95% CI, 4.00-4.06] per 100 000 population) (Table). Statistically significant diverging trends were observed in the 2 regions between 1999 and 2020, with AAMRs stable in Appalachia (AAPC, −0.05% [95% CI, −0.24% to 0.13%] per year), but decreasing in non-Appalachia (AAPC, −0.85% [95% CI, −1.01% to −0.69%] per year; P < .001). Within Appalachia, the highest AAMRs were found in the Central (5.64; 95% CI, 5.22-6.05) and North Central subregions (5.17; 95% CI, 4.82-5.51) (Figure). HNC mortality trends for 1999 to 2020 increased a statistically significant 0.52% (95% CI, 0.05%-0.99%) per year in the North Central subregion but were stable in all other subregions.

Table. Head and Neck Cancer Age-Adjusted Mortality Rates (AAMRs; 2016-2020) and Average Annual Percentage Change (AAPC; 1999-2020) by Appalachian Status and Urbanicity^a.

Location	2016-2020			1999-2020
	Average population	No. of deaths	AAMR (95% CI)	AAPC (95% CI), %
US	326 747 554b	83 477	4.09 (4.06 to 4.12)	−0.79 (−0.95 to −0.63)
Rural US, No. (%)	46 076 207 (14.1)	15 710	4.74 (4.66 to 4.81)	0.02 (−0.15 to 0.19)
Appalachia	25 803 508	8278	4.62 (4.52 to 4.72)	−0.05 (−0.24 to 0.13)
Rural Appalachia, No. (%)	8 706 254 (33.7)	3212	5.06 (4.88 to 5.24)	0.46 (0.20 to 0.72)
Non-Appalachia	300 942 177	75 199	4.03 (4.00 to 4.06)	−0.85 (−1.01 to −0.69)
Rural Non-Appalachia, No. (%)	37 369 953 (12.4)	12 498	4.66 (4.58 to 4.74)	−0.08 (−0.26 to 0.11)

^a Data are from the Appalachian Regional Commission² and Centers for Disease Control and Prevention WONDER (Wide-Ranging Online Data for Epidemiologic Research) underlying cause of death, 1999-2020, dataset.³

^b A total of 9436 individuals were included with unknown county of residence.

Figure. Head and Neck Cancer Mortality by Appalachian Subregion.

This map illustrates age-adjusted mortality rates (AAMRs) per 100 000 people by Appalachian subregion. The average annual percentage change (AAPC) in AAMRs between 1999 and 2020 is also presented.

^aAAPC is statistically significantly different than 0.

In rural Appalachia, HNC mortality increased 0.46% (95% CI, 0.20%-0.72%) per year, with a statistically significant divergence from stable trends in rural non-Appalachia (−0.08% [95% CI, −0.26% to 0.11%]; P < .001). Increases in the North Central subregion included statistically significant increases among the 44.1% of the population living in rural areas (0.83% [95% CI, 0.10%-1.56%] per year).

Discussion

In contrast to non-Appalachian US, where HNC mortality rates declined considerably between 1999 and 2020, HNC mortality rates in the Appalachian region have remained stubbornly stable. Moreover, statistically significant increasing rates of HNC mortality in rural Appalachia provide evidence that the lack of rural HNC mortality improvements nationwide are associated with Appalachian disparities.

While the exact factors driving these trends are unknown, the Appalachian region has an increased prevalence of multiple risk factors associated with cancer mortality, such as adverse social determinants of health, heightened alcohol and tobacco use, later stage at diagnosis, and limited access to care.^1,4,5 One limitation of this study is that further investigation into the specific factors driving mortality in the Appalachian region, such as smoking prevalence and human papillomavirus vaccination rates, is currently hindered by the lack of an Appalachian variable in most national surveillance datasets. Investments in the Appalachian region—such as through the Bipartisan Infrastructure Law or by expanding coverage of the National Cancer Institute’s Surveillance, Epidemiology, and End Results Program among Appalachian states—could help reduce the burden of HNC mortality by improving cancer surveillance and serving the unique needs and experiences of the Appalachian population. These investments could also aid efforts to improve other cancer sites with known disparities in Appalachia, such as lung and colorectal cancers.⁶

Supplement.

Data Sharing Statement