What does the epidemic of prescription painkillers have to do with the results of the 2016 presidential election? Perhaps more than one might think, suggests a study from University of Texas researchers.

The counties with the highest opioid prescription rates in 2015 were also more likely to favor presidential candidate Donald Trump in 2016, the national study found.

Support for Trump was as strong a marker of an area’s opioid rates as some commonly used socioeconomic factors — such as household income, education levels and unemployment, the study said.

The cross-sectional analysis, published Friday in JAMA Network Open, used data from the U.S. Census, Medicare Part D and uselectionatlas.org to explore a phenomenon some others have deemed an "oxy electorate."

But terms like that may be misleading, and in no way does the study suggest people abusing painkillers voted for Trump, said Dr. James Goodwin, the study's lead author and chair of geriatric medicine at the UT Medical Branch in Galveston.

"With an ecological analysis, you can't say that. And not only can't you say it, but it's probably not true," said Goodwin, who has authored several studies looking at opioid use among Medicare beneficiaries, which piqued his curiosity in the topic.

"If you're stoned out on opioids, you're probably not voting," he said.

The study simply suggests an association at the county level. And the overlap, he and others say, could indicate that people in depressed areas, where feelings of being disenfranchised or left out run rampant, may be more likely to support candidates promising to bring big changes.

“Trump tapped into something in that segment of voters,” said Katharine Neill Harris, a drug policy fellow at the Baker Institute, a nonpartisan think tank at Rice University in Houston. She was not involved in the study, but says it’s an interesting area of research that should be more thoroughly explored.

“It’s about more than just prescriptions,” she said. “This is a very complex relationship, and representative of a deeper problem ... of problems we are not addressing as a society.”

That sentiment was shared by Zachary Simoni, a medical sociologist in UT Dallas' School of Economic, Political and Policy Sciences. He noted the departure of manufacturing and other jobs that has created an economic downturn and shared frustration in rural communities.

The study focused on legally available prescription pain relievers, like oxycodone and hydrocodone, codeine and morphine, but not illegal substances like heroin.

The drugs' addictive qualities have resulted in a national opioid crisis. An estimated 11.5 million Americans misused prescription opioids and 2.1 million had an opioid use disorder in 2016, according to the U.S. Department of Health and Human Services.

The concern has led local governments in Texas and other states to file lawsuits against drug companies, claiming they oversold the benefits but downplayed the risks of addiction.

Discussions about election patterns that focus on socioeconomics should spill over into conversations about solving the opioid epidemic, Goodwin said.

The study looked at the records of more than 3.7 million people enrolled in Medicare Part D, whose identities were hidden. The enrollees represented 3,128 of the 3,142 counties listed by the census for that year.

Those who had received at least a 90-day supply of opioids in 2015 fell into the category of high opioid users. A total of 693 counties — often in areas with populations of fewer than 1 million — had adjusted rates of opioid prescriptions that were significantly higher than the national mean. There were 638 counties with rates of opioid overuse that were significantly lower.

A vote for Trump in 2016 was one of the biggest differences between counties with the highest and lowest rates, the study found. Of the people in counties with the highest rates, 59.96 percent voted for Trump in 2016, compared to 38.67 percent in areas with the lowest usage of the prescription medications.

The counties where the overlap was greatest were clustered in the South, Midwest and the lower part of the Appalachia region, a map in the study showed.

Map A shows the counties where residents had the highest percentage of long-term opioid use in 2015. Map B shows the the percentage of votes by county for presidential candidate Donald Trump in 2016. (JAMA Network Open)

The authors noted several limitations. For example, while the 2016 county presidential vote included all voters, the prolonged opioid rates only accounted for about 72 percent of the Medicare population, generally seniors. Also, prescriptions only account for about half of all opioid-related deaths in the U.S.

And the study could explore only county-level data and did not look at other factors influencing an individual’s voting decisions.

Still, the findings add to the literature by showing that public health does not exist in a vacuum, and if the results can be replicated, they can be used to highlight how public policies affect mental status, said Dr. James Rosenquist of Massachusetts General Hospital in commentary that accompanied the study.

Interestingly, fewer Texas counties experienced the overlap that the study highlighted.

There were a significant number of counties where more than 70 percent of the votes went to the Republican candidate in 2016, but there were relatively few counties with the highest opioid rates.

The introduction of 2010 "pill mill" legislation in Texas led to clinically significant reductions in opioid dose, volume, prescriptions and pills dispensed, previous studies have found.

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