By Melissa Healy

An epidemic of despair is disproportionately claiming the lives of rural white Americans in the prime of adulthood. And for a second year in a row, their deaths by drugs, drink and self-destruction have caused life expectancy in the United States to fall.

That milestone, suggests an editorial in a respected medical journal, marks a sustained reversal of close to a century of improving health for Americans. And it raises a puzzling mystery: What is causing the despair, and what will restore hope and health to these battered Americans?

The opioid epidemic, which claimed the lives of 64,000 Americans in 2015 alone, "is the tip of an iceberg," a pair of public health scholars wrote.

In an even larger public health crisis unfolding in the United States, death rates from alcohol abuse and suicides have also seen sharp increases in recent years, wrote Steven H. Woolf of Virginia Commonweath University and Laudan Aron of the Washington-based Urban Institute.

Between 1999 and 2014, the suicide rate rose by 24%. And mounting evidence has shown that deaths linked to alcohol abuse are rising as well among white Americans.

Nowhere are these trends more dramatic than in rural counties, where decades of social and economic changes have made the lives of white Americans less secure than their parents', Woolf and Aron wrote.

About 15% of the nation's population — some 46 million persons — lived in counties outside metropolitan areas in 2014. In a January 2017 analysis, the Centers for Disease Control and Prevention reported that those living in nonmetropolitan areas were more likely to smoke cigarettes, to be physically inactive and obese and to suffer from high blood pressure than were metropolitan county-dwellers.

Fully 18.1% of rural Americans lived in poverty, compared with 15.1% of those living in and around cities. And people in rural counties reported less access to healthcare and a lower quality of healthcare than did those in metropolitan counties.

In October, a study published in the American Journal of Public Health found that, while premature deaths were down among all American adults between 1999 and 2015, nine of 48 subgroups studied saw increases in early mortality. The lives of non-Latino whites, largely in rural or small or medium metropolitan counties, were mostly being shortened by suicide, drug overdoses and liver disease — a condition closely linked to alcoholism.

That study's data showed steep declines in deaths due to HIV infection, cardiovascular disease and motor vehicle crashes among African Americans and Latinos and in urban and suburban areas. But those declines were more modest or nonexistent among whites living in any setting. And they were offset by dramatic increases in drug overdoses and suicides in whites, no matter where the victims lived.

The authors of the essay note that the roughly 15-year run-up in drug deaths and suicides has not been seen in black Americans.

While the racial gap in health is narrowing, African Americans' rates of premature death have always been starkly higher than those among whites, Woolf said. And it may be that the uptick in "deaths of despair" seen in whites will eventually be detected among blacks as well, he added.

But Woolf said it's also possible that black Americans have some "resilience factor" that white Americans do not. Perhaps, he said, African Americans' response to the discrimination, structural disadvantages and health inequities they've long endured has buffered them from following whites down their path of self-destruction.

At the same time, the despair of whites is "unclear, complex, and not explained by opioids alone," Woolf and Aron wrote. In once-thriving communities outside the nation's metropolitan areas, industries have collapsed. As steel mills and coal mines have closed, timber production has gone bust, and automation has left rural communities behind, their economies and their residents' health have suffered.

The result is a national phenomenon that has been unfolding for at least three decades. Relative to life expectancy in other affluent, industrialized countries, Americans' once-commanding lead in longevity began slipping in the early 1980s. By 1998, U.S. life expectancy had fallen below the average for industrialized countries. It is now 1.5 years behind that benchmark.

"It's really sad that a baby born today will likely live less long than one born even a year ago. It's not the direction you'd expect the richest country on Earth to be going," Woolf said.

But economic collapse might be too easy an explanation for rural white communities' epidemic of despair, said Woolf, who has studied the urban-rural health divide across the country. More important might be the fraying of communities' social fabric that followed.

"Poverty rates don't capture the frustration and hopelessness people experience when they can't get ahead or can't give their kids a better life," Woolf said. When the social fabric of a community is frayed, its residents may be more inclined to salve their woes in self-destructive behaviors, he added.

A look at broader U.S. trends and policies may also shed light on the roots of some Americans' despair, Woolf and Aron wrote. During the three decades during which U.S. life expectancy has slid, the nation's educational performance weakened. Its social divides (including income inequality) widened. Its middle-class incomes stagnated. And its poverty rates exceeded those of most rich countries.

"These are all factors we know are important to health," Woolf said.

If policy makers wanted to reverse the trend of shortening U.S. lifespans, "they would promote education, boost support for children and families, increase wages and economic opportunity for the working class, invest in distressed communities, and strengthen healthcare and behavioral health systems," Woolf and Aron wrote.

At the end of the day, Woolf said, "it's probably not a good time to make policy choices that don't invest in helping these people. A policy agenda that's focused on improving value for shareholders is not really going to bring relief to these families and communities."