Photos.com/Hemera/Thinkstock(NEW YORK) — The white working class in the U.S. has bucked a global trend of improved mortality rates in recent years as a host of factors including suicide, opioid addiction and alcohol-related liver disease have increasingly claimed lives.

A new report published in the Brookings Papers on Economic Activity focuses on looking at this trend of rising mortality and possible factors that have led to it.

“Ultimately, we see our story as about the collapse of the white, high school educated, working class after its heyday in the early 1970s, and the pathologies that accompany that decline,” the authors Anne Case and Angus Deaton, of Princeton University wrote in the report.

Case and Deaton both drew attention after publishing a 2015 paper that found the white working class has had growing mortality rates, while other groups including white people with college degrees continued to have declining rates of mortality. They now are expanding on the research to better understand that trend and to see if they can could come up with a preliminary hypothesis for the rise in mortality in this group.

According to the report, white non-Hispanic people of all ages show an increased mortality rate from 1999 to 2015 with some age groups seeing nearly a 50 percent rise in mortality rates. People aged 25-29 went from a mortality rate of 145.7 deaths per 100,000 in 1999 to 266.2 per 100,000 in 2015 and people aged 40-44 went from 332.2 deaths per 100,000 to 471.4 deaths per 100,000.

Case and Deaton found that while gains were made as fewer people died of heart disease and cancer, these gains have mostly stagnated and did not cancel out the rising number of “deaths of despair” or related to alcohol, drugs or suicide.

In 1990, France, Germany and Sweden outpaced the U.S. in these deaths which totaled approximately 40 per 100,000 from those countries. After 2000 white non-Hispanic people in the U.S. were far more likely to die of these causes then their foreign counterparts with the related mortality rate reaching 80 deaths per 100,000 people, according to the report. Opioids alone kill an estimated 91 people in the U.S everyday according to the U.S. Centers for Disease Control and Prevention.

Case and Deaton theorize multiple factors have helped cause this worrying rising mortality rate, but are careful to acknowledge these are preliminary theories. They point out that while stagnating wages can lead to feelings of hopelessness and despair, they say there is not clear enough evidence that it was a sole factor. Instead they theorize that a steady deterioration in job opportunities for people with only a high school education as well as weakening social structures may have contributed to increasing numbers of “deaths by despair.”

The researchers say that automation and globalization diminished the opportunities for people with a high school diploma or less, while diminishing wages may have affected marriage rates and led to a rise of less stable partnerships. They also point to past studies that have found more people are moving away from the churches of their parents and grandparents to churches focused “seeking an identity” or no church at all.

“These changes left people with less structure when they came to choose their careers, their religion, and the nature of their family lives. When such choices succeed, they are liberating; when they fail, the individual can only hold him or herself responsible,” they wrote.

With longstanding forces possibly contributing to this rise in mortality rates, the authors have some suggestions but acknowledge little will be “quickly reversed by policy.”

“Controlling opioids is an obvious priority, as is trying to counter the negative effects of a poor labor market on marriage, perhaps through better safety nets for mothers with children,” they wrote.

Dr. Peter Muenning, the Director for the Global Research Analytics for Population Health at the Columbia University Mailman School of Public Health, said public health experts have still been stymied by the rise in mortality rates for this group and for the drop in life expectancy in the U.S. overall.

Last December life expectancy in the U.S. dropped for the first time since 1993. He said the other times they’ve seen a dip in life expectancy include major traumatic events like the 1918 influenza outbreak, the break up of the Soviet Union and the rise of HIV in Africa.

“When we see a slowing and a decline that’s a huge warning sign for me,” Muenning said. “It’s not a one point blip and going down, it’s the long term trend of the slowing.”

Muenning said overall there is not a clear reason for the mortality increase or the drop in American life expectancy.

“It’s probably a multi-factorial problem but it seems like the inequality story is one of the bigger contributors.” Muenning explained that inequality and less opportunity is associated with an increase in mortality but it is difficult to pinpoint a reason why. Additionally he said it’s not clear that unequal opportunities for this group compared to others would explain such a large increase.

“We don’t really in public health have a strong explanation for why inequality kills people but it is correlated with mortality and higher crime … those correlations are not strong enough to explain something like this,” he said.

Additionally he points out that when life-expectancy decreased it was in part due to other factors that did not match up with the “deaths by despair” explanation.

“There’s lots of things like kidney failure and random things that have really increased over the last few years” to cause deaths, said Muenning. “That sort of in my mind deepens the mystery.”

While obesity has also been looked at as a factor, Muenning points out that other countries have experienced huge increases in obesity with mortality rates still decreasing.

“We should definitely be better than we’re doing,” he said.

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