Mortality gap widened as politics influenced U.S. health years before pandemic hit

Studies examine COVID-19 and other causes of death in counties leaning Republican or Democratic.

The COVID-19 pandemic caused more deaths in counties where voters picked Republican candidates than in U.S. counties where voters favored Democrats.

But from 2001 to 2019, even before COVID-19 swept across the United States, there was a growing “mortality gap,” the difference between age-adjusted mortality rates (AAMRs), in counties that voted for Democratic or Republican candidates for president and governor. The findings were in separate studies published this week.

“In an ideal world, politics and health would be independent of each other and it wouldn’t matter whether one lives in an area that voted for one party or another,” Haider Warraich, MD, corresponding author of one of the studies, said in a news release. “But that is no longer the case. From our data, we can see that the risk of premature death is higher for people living in a county that voted Republican.”

Mortality gap

From 2001 to 2019, researchers found AAMRs decreased by 22%, from 850 deaths per 100,000 people to 664, in Democratic counties. The rate dropped by 11%, from 867 to 771 deaths per 100,000 people in Republican counties, according to the study, “Political environment and mortality rates in the United States, 2001-19: population based cross sectional analysis,” published June 7 in the British Medical Journal.

Data came from the federal Centers for Disease Control and Prevention Wide-ranging OnLine Data for Epidemiologic Research, known as CDC WONDER, and the Massachusetts Institute of Technology Election Data and Science Laboratory. Researchers classified counties as Democratic or Republican based on the way the county had voted in the previous presidential election and adjusted for age when calculating mortality rates.

The mortality gap remained consistent in counties that voted Republican or Democratic in every presidential election year studied, and when they looked at gubernatorial elections. Democratic counties experienced greater reductions in mortality rates across most common causes of death, including heart disease, cancer, chronic lower respiratory tract diseases, diabetes, influenza and pneumonia, and kidney disease, the news release said.

Political influence on health

The authors acknowledged the study detected an association, not a definitive link, but they noted the widening gap in death rates may reflect the influence of politics on health policies. For example, when the federal Affordable Care Act was passed in 2010, more Democratic states than Republican states adopted Medicaid expansion and people with lower incomes gained health insurance coverage.

“Our study suggests that the mortality gap is a modern phenomenon, not an inevitability,” said Warraich, of Brigham and Women’s Hospital in Boston and Harvard Medical School. “At the start of our study, we saw little difference in mortality rates in Democratic and Republican counties. We hope that our findings will open people’s eyes and show the real effect that politics and health policy can have on people’s lives.”

Pandemic partisanship

The mortality gap study period occurred before the COVID-19 pandemic started in 2020. After that, counties where 70% or more voted Republican had nearly 73 more COVID-19 deaths per 100,000 people, compared to Democratic counties where less than 30% voted Republican. Those findings were in a separate research article, “The Association Between COVID-19 Mortality And The County-Level Partisan Divide In The United States,” published June 6 in the journal Health Affairs.

The disparity in mortality rates between Republican and Democratic counties was due largely to structural, policy and behavioral differences in the more conservative counties, co-authors Neil Jay Sehgal, PhD, MPH, of the University of Maryland, and Dylan Roby, PhD, of the University of California Irvine Program in Public Health, said in a news release.

“Voting behaviors at the county level are likely to represent the compliance or lack of compliance with mask mandates, vaccine uptake and use of other protective policies to mitigate the impacts of the pandemic,” Roby said. The findings were based on COVID-19 deaths through October 2021 and county voting data in the 2020 presidential election.

Break with custom

Beyond the pandemic, the next key political influences on health could happen in “state governments, where tectonic shifts in policy are occurring,” said Steven Woolf, MD, MPH, of Virginia Commonwealth University’s Department of Family Medicine & Population Health. He wrote an editorial, “Politics and mortality in the United States,” that accompanied the mortality gap study in the British Medical Journal.

“While gridlock in Washington, DC incapacitates the federal government, Republican leaders in dozens of state capitols are passing laws to undermine health and safety regulations, ban abortion, limit LGBT+ rights, and implement more conservative policies on voting, school curriculums, and climate policy,” Woolf wrote. “To understand the implications for population health, researchers must break with custom; although scientific literature has traditionally avoided discussing politics, the growing influence of partisan affiliation on policies affecting health makes this covariate an increasingly important subject of study.”