(Reuters Health) - Voters in counties where life expectancy has stagnated and declined in recent years were more likely to abandon the Democratic Party to help elect U.S. President Donald Trump, a new study suggests.

The study examined county-level data on voting patterns from the 2008 and 2016 presidential elections and on life expectancy for people born from 1980 to 2014.

Nationally, life expectancy increased by an average 5.3 years during the study period, researchers report in the American Journal of Public Health, online August 17.

In counties with below-average gains in life expectancy or declines, a majority of voters chose Trump, the Republican nominee. But in counties with above-average gains in life expectancy, most voters chose the Democratic candidate Hillary Clinton.

“Although economic marginalization has been cited as a reason for shifting voting patterns, the relationship between changes in life expectancy and the 2016 election results had not been previously documented,” said study author Jacob Bor of the Boston University School of Public Health.

“The very strong association is striking and suggests that the large divergence in health fortunes has mirrored the divergence in politics,” Bor said by email.

To assess the connection between survival odds and political participation, Bor looked at changes in the Republican share of votes between 2008 and 2016 as well as shifts in the absolute numbers of votes won by each of the two major political parties.

Overall, Republicans lost 67,000 votes from 2008 to 2016 in counties with above-average gains in life expectancy but gained 3.1 million votes in counties with below-average life expectancy trends.

During the same period, Democrats gained 1.4 million votes in counties with above-average life expectancy gains but lost 5 million votes in counties with below-average gains.

Counties where life expectancy stagnated or declined saw a 10-percentage-point increase in the Republican vote share between 2008 and 2016, the study found.

In counties where life expectancy increased by less than 3 years over the study period, the Republican vote share increased on average by 9.1 percentage points.

For each additional year of life expectancy gain, the change in Republican vote share was 2.3 percentage points lower.

Democrats, meanwhile, saw an average 3.5-percentage-point increase in vote share in counties where life expectancy gains exceeded 7 years.

The study wasn’t a controlled experiment designed to prove whether or how life expectancy might directly influence voting.

But Bor notes that since coming to power, the Trump administration has proposed cuts to health insurance for the poor, social programs, health research, and environmental worker protections that are all are key determinants of health at the population level and might influence life expectancy in the future.

“This study confirms what we already know,” said Dr. Vicente Navarro, a health policy researcher at the Bloomberg School of Public Health at Johns Hopkins University in Baltimore. “The standard of living and quality of life of the majority of the working class of the U.S. has been declining.”

“They are angry and channel their anger against what they consider the political establishment, voting for Trump,” Navarro, who wasn’t involved in the study, said by email. “The paradox is that President Trump is carrying out policies that will further reduce their life expectancy.”

Even though the study doesn’t prove life expectancy influences voting decisions, many health problems that can contribute to a premature death can also fuel voter dissatisfaction with the status quo, said Jose Tapia, a politics researcher at Drexel University in Philadelphia who wasn’t involved in the study.

“Higher mortality rates can be caused for instance by more frequent deaths due to diabetes, overdose of prescription or illegal drugs, alcohol abuse, suicide or heart attacks, all of which can be correlated with higher rates of dissatisfaction with standards of life or current politic, which can lead to vote against the party in power,” Tapia said by email.

SOURCE: bit.ly/2xpLmHl

Am J Public Health 2017.