Raising the minimum wage could lower the suicide rate, according to a study published last week, delivering labor advocates a tantalizing new finding about the broader impacts of wage changes even as some experts said other factors could explain the decrease.
More than 47,000 Americans died by suicide in 2017, and with other so-called deaths of despair — drug overdoses and alcoholism — it has grown into a slow-motion public health crisis. The phenomenon is difficult to study, and researchers have struggled to find effective prevention strategies.
The new study examined suicide rates from 1990 through 2015 across all 50 states and Washington, and measured how they changed as the minimum wage increased. The researchers focused on adults between 18 and 64 years old with a high school education or less — a group more likely than others to be affected by changes in the minimum wage.
When controlling for changes in a state’s economy and welfare policies, the researchers estimated that a $1 increase in the minimum wage corresponded with a 3.5 percent decrease in the suicide rate for those with a high school education or less. Without some of the controls, the decrease in the suicide rate was 6 percent. The effect was most pronounced during times of high unemployment.
“The real world is a living natural experiment,” said John Kaufman, a doctoral student in epidemiology at Emory University and the lead author of the study, which was published on Jan. 7 in the Journal of Epidemiology and Community Health.
“Yes, there are possible alternative explanations to what we saw, but these aren’t crude associations, these aren’t mere correlations,” he said. “We designed the study to account for multiple types of alternative explanations.”
The study echoed other findings about the nonfinancial effects of minimum wage increases. They have been linked to less chronic disease in adults, lower premature mortality and fewer cases of child maltreatment, said Yannet Lathrop, a researcher and policy analyst at the National Employment Law Project, a nonprofit organization based in New York that supports workers’ rights.
Mr. Kaufman’s research drew national attention in recent days, coming as suicide rates continue to climb and a movement to raise minimum wages sweeps across the country. Democrats in the House pushed through a bill in July that would more than double the federal minimum wage, raising it to $15, and dozens of states and cities have enacted similar wage increases.
“Raising the minimum wage by $1 could’ve prevented thousands of suicides a year,” Senator Bernie Sanders of Vermont, a leading progressive candidate in the presidential race, said in a tweet about the study. “We will end the 40-year assault on the working class and the suffering it has caused for our people.”
Some politicians raised questions about the study’s findings.
A spokesman for Senator Mike Lee, Republican of Utah, who leads a congressional committee that has examined suicides, told The Washington Post last week that the office had a different interpretation.
“Our reading,” said the spokesman, Conn Carroll, was that the paper showed that a higher “state minimum wage over the federal minimum wage is correlated with less suicide.”
“By this logic, if we raised the federal minimum wage while keeping state minimum wages constant, suicide would go up!” he said. “Or, we could really reduce suicide by eliminating the federal minimum wage entirely thus creating a huge gap between state minimum wages and the federal one. These seem nonsensical.”
Mr. Carroll declined to answer further questions seeking clarification.
Mr. Kaufman said that he did not expect the study to draw so much attention, and that it was part of a series examining changes in economic policy — unemployment programs and tax credits, for example — and how they affect people’s health.
“My approach is, when there’s a disagreement, there’s room to learn,” he said. “But only if people recognize that maybe they don’t know everything.”
Aparna Mathur, a resident scholar in economic policy studies at the American Enterprise Institute, a conservative think tank, said the study’s findings made sense. But she said she was concerned about not knowing what specifically drove decreases in the suicide rate.
“Are we adequately controlling for everything else?” she said. “Do we know that when people have high minimum wages they tend to go to the doctor more? They seek more help for depression?”
She said policymakers focusing on suicides may be ignoring potential costs of raising minimum wages, such as a reduction in hours worked.
Dr. Mark Olfson, a professor at Columbia University who studies the impact of socioeconomic factors on suicide rates, said he did not find the results of Mr. Kaufman’s study persuasive.
He said looking at large groups of people, instead of homing in on specific individuals, allows for other factors to affect the suicide rates — even if the study tried to control for some of them.
“It introduces room for spurious associations or associations that are hidden in their overall finding,” Dr. Olfson said.
He said that when taking into account the margin of error, the change the researchers found in the suicide rate was too small to make solid conclusions.
“You make sound public policy decisions in part based on strong empirical evidence — at least that’s the hope,” he said. “Studies that don’t meet some basic standard, really, I think don’t think have much of a role in the discourse.”
But Dr. Margot Kushel, the director of the Center for Vulnerable Populations at the University of California, San Francisco, said there would most likely be no other way to study the impact of minimum wage on suicide. Dr. Kushel, who is also a professor of medicine, said the study was “well done,” noting that it was not the first to link minimum wage increases to decreases in suicide.
“When you start to see so many well-done studies pointing in the same direction, it has to get you to think there may be something here,” she said.
She said researchers can “never adjust for all confounders.”
To Fran Marion, a shift manager at a McDonald’s in Kansas City, Mo., who has been pushing for a higher minimum wage, the study’s findings were not surprising.
She said she knew workers who had died by suicide and who were stressed about providing for themselves or their families. She said she herself had been depressed when she struggled to pay for her health care or healthy food for her children.
“I’ve been in those dark places, too,” she said, “where I don’t want to wake up or I just want to give up because I’m tired of struggling.”