About 14,500 new cases of invasive cervical cancer are diagnosed each year in the United States and nearly 4,300 women die from the disease. Studies show that those living in higher-poverty areas experience higher rates of morbidity and mortality from many preventable cancers, including cervical cancer. Although the human papillomavirus (HPV) vaccine has made the near-elimination of cervical cancer in the United States possible, health disparities may delay reaching this goal.

The results from a study by Spencer et al published in Cancer Epidemiology, Biomarkers & Prevention investigating the effects of HPV vaccination on disparities in cervical cancer incidence between high- and low-poverty counties in the United States showed that low-poverty counties will achieve near-elimination targets 14 years earlier than high-poverty counties—by 2029 vs 2043, respectively. As a result, it is estimated that there will be 21,604 excess cases of cervical cancer in high-poverty areas over the next 50 years.

Study Methodology

The researchers created a simulation model of HPV infection to reflect average counties in the highest and lowest quartile of poverty (the percentage of population below federal poverty level) in the United States, incorporating data on HPV prevalence, cervical cancer screening, and HPV vaccination rates. They developed two versions of the model: one of a hypothetical county in the lowest-poverty quartile and one of a county in the highest-poverty quartile. The researchers used immunization data for low- vs high-poverty areas from the National Immunization Survey-Teen; screening and follow-up data from the National Health Interview Survey; and HPV prevalence data from the National Health and Nutrition Examination Survey. They then projected cervical cancer incidence through 2070; estimated absolute and relative disparities in incident cervical cancer for high- vs low-poverty counties; and compared incidence with the near-elimination target (4 cases per 100,000 women annually).

Results

The models estimated that, on average, low-poverty counties will achieve near-elimination targets 14 years earlier than high-poverty counties—in 2029 vs 2043, respectively. The models predicted that absolute disparities by county poverty will decrease, but relative differences are estimated to increase. The researchers estimated that there will be 21,604 cumulative excess cervical cases in high-poverty counties over the next 50 years.

Increasing HPV vaccine coverage nationally to the Healthy People 2020 goal of 80% would reduce excess cancer cases, but not alter the estimated time to reach the near-elimination threshold, according to the researchers.

“High-poverty U.S. counties will likely be delayed in achieving near-elimination targets for cervical cancer and as a result, will experience thousands of potentially preventable cancers,” concluded the study authors.

“Other studies have predicted that, as a whole, the U.S. will hit the elimination target in the middle of that range,” said lead study author Jennifer Spencer, PhD, Assistant Professor at the Dell Medical School at The University of Texas at Austin, in a statement. “The fact that some places will hit it a decade before other places is a little bit of gut punch. Vaccination can do a lot of good, but it’s unlikely that the disparities can be addressed through just vaccination. The next step is to identify what policies we can use to close these gaps in the future.”

Disclosure: Funding for this study was provided by the University of North Carolina’s Cancer Care Quality Training Program and the Dana-Farber/Harvard Cancer Center Training in Oncology Populations Sciences Program. For full disclosures of the study authors, visit cebp.aacrjournals.org.