Mortality rates since 2001 have decreased more in Democratic counties than in Republican counties, creating a widening mortality gap, a new study shows.
The study, conducted in part by investigators from Brigham and Women’s Hospital, examined mortality rates and federal and state election data across the country from 2001 to 2019. They found a mortality gap — or a widening difference in death rates — between counties that had voted for a Democrat or a Republican in previous elections.
Specifically, mortality rates fell 22% in Democratic counties, as compared to only an 11% decrease in Republican counties.
“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,” Dr. Haider Warraich, a corresponding author of the study and member of the Division of Cardiovascular Medicine at Brigham, said in a statement. “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.”
This pattern was consistent across various subgroups explored in the study, including sex, race and ethnicity, and urban-rural location.
The study found that the age-adjusted mortality rate for both men and women was lower and improved more in Democratic counties than Republican ones.
The researchers found Black Americans throughout the study had higher mortality rates than white or Hispanic Americans. They also found that for Black and Hispanic Americans, there was “little gap” between improvement in the mortality rates experienced in Democratic and Republican counties.
While the age-adjusted mortality rate decreased consistently for Black residents of Democratic counties, Black residents of Republican counties experienced increases in mortality rate over several age ranges, according to the researchers.
Over the 18 years covered in this study, the gap in mortality rate between white residents of Republican and Democratic counties grew fourfold — the largest increase in any gap for a racial or ethnic group.
When looking at the most common causes of death, Democratic counties saw greater reductions in mortality rate. Common causes of death include heart disease, cancer, chronic lower respiratory tract diseases, diabetes, influenza and pneumonia, and kidney disease, according to the study.
The researchers found heart disease and cancer remain the leading causes of death in counties regardless of political affiliation. But they discovered declines in death from heart disease were more pronounced, resulting in a widening gap. By the end of the study period, Republican counties saw higher mortality rates than Democratic counties for cancer as well.
The study’s authors noted that the widening gap in death rates may reflect health policies and politics; the researchers detected an inflection point in 2010 when the Affordable Care Act passed. More Democratic states adopted Medicaid expansions, according to the study, which expanded health insurance coverage to people on a low income and may be reflected in mortality statistics.
In a press release about the study, the authors also noted that their research ended before the COVID-19 pandemic, which “may have had an even more profound impact on the mortality gap.”
“Our study suggests that the mortality gap is a modern phenomenon, not an inevitability,” Warraich said. “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.”
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