The culture of different areas ―what people see others around them doing, the habits they adopt —tends to perpetuate the differences in life expectancy over time.(Photo: Shutterstock)

In an era when "deaths of despair" — from substance abuse andsuicide — are on the rise among middle-aged Americans, those whoreach age 65 are living longer than ever.

But there's a catch: Seniors in urban areas and on the coastsare surviving longer than their counterparts in rural areas and thenation's interior, according to an analysis from Samuel Preston of the University of Pennsylvania,one of the nation's leading demographers.

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This troubling geographic gap in life expectancy for olderAmericans has been widening since 2000, according to his research,which highlights growing inequality in later life.

Notably, 65-year-olds in "rural areas have had much smallerimprovements than those in large metro areas," Preston remarked."And people living in 'interior' regions ― particularly Appalachiaand the East South Central region [Alabama, Kentucky, Mississippiand Tennessee] — have done worse than those on the coasts."

These geographic differences emerged around 1999-2000 andwidened from 2000 to 2016, the study found. By the end of thisperiod, life expectancy at age 65 for women in large metropolitanareas was 1.63 years longer than for those in rural areas. For men,the gap was 1.42 years.

Differences were even starker when 65-year-olds who live inmetro areas in the Pacific region (the group with the best results)were compared with their rural counterparts in the East SouthCentral region (the group with the worst results). By 2016, seniorsin the first group lived almost four years longer. (The Pacificregion includes Alaska, California, Hawaii, Oregon andWashington.)

"Areas with the highest life expectancies at age 65 haverealized more significant improvements between 2000 and 2016, whileareas with the lowest life expectancies have gained the least,"said Yana Vierboom, a co-author of the new study and a postdoctoralresearcher at the Max Planck Institute for Demographic Research inGermany.

Disparities were also highlighted when researchers examined lifeexpectancy at 65 in the U.S. and 16 other developed nations, using2016 data. Overall, the U.S. was near the bottom of the pack:American men ranked 11th while American women were in 13th place,behind leaders such as Japan, Switzerland, Australia, France, Spainand Canada.

But when only 65-year-old American men living in Pacific regionmetro areas were considered, they topped all other countries, withan added life expectancy of 20.03 years. Women from this advantagedgroup also jumped in the rankings to the No. 4 position, with alife expectancy of 22.79 additional years.

Pockets of this country "have a life expectancy at 65, which ison par" with that of leading countries, Jennifer Karas Montez, aprofessor of sociology at Syracuse University, wrote in an email."We need to figure out what those places are doing right and thentake those lessons and apply them to other parts of the countrythat are doing poorly."

What distinguishes areas that are doing well from those thataren't?

According to the new study, the most important factor is areduction in deaths from cardiovascular illnesses, such as heartattacks and strokes — the biggest killer in America.

"It's likely that medical treatments for cardiovascular diseasehave disseminated more rapidly in large metro areas than in ruralareas," which have fewer specialist physicians and hospitals,Preston said.

The second-most important factor, especially for women, wassmoking, a contributor to cardiovascular disease, lung cancer andrespiratory diseases.

"There are large differences in smoking rates across thecountry," with more women in the South and rural areas taking upsmoking and more women in metro areas who've given up the habit,Vierboom said.

While the analysis that Preston and Vierboom conducted didn'texamine race, income or education, it's certain that these factorsplay a part in its findings.

"Geographic differentiation isn't random: People who are poor,or who smoke or who are obese tend to be concentrated in certainplaces," said Eileen Crimmins, AARP professor of gerontology at theUniversity of Southern California.

Meanwhile, the culture of different areas ― what people seeothers around them doing, the habits they adopt — tends toperpetuate these differences over time.

While enormous attention has been paid to "deaths of despair" inthe younger and middle-aged population, the "real action" regardingmortality is with the 65-and-older population, Crimmins said. Ofnearly 3 million people who die each year in the U.S., almostthree-quarters are age 65 or older.

Deaths from opioids, alcohol or suicide aren't significant inthe older population; instead, deaths from chronic illnesses, whichtake years to develop and which are influenced by social conditionsas well as personal behaviors, are far more important, Prestonnoted.

This helps explain another notable trend spotlighted in his newresearch: Life expectancy at age 65 has steadily increased, even inan era when "deaths of despair" have been on the rise.

The long-term trend is upward. In 1950, a65-year-old could expect to live an additional 13.9 years, onaverage (15 more years for women, 12 for men). A half-centurylater, in 2000, life expectancy at age 65 had climbed to 17.6additional years (19 for women, 16 for men). By 2018,it increased again, adding 19.5 years (20.7 for women, 18.1 formen).

This positive trend has persisted even as deathrates due to drug and alcohol abuse, suicide and chronicconditions, such as hypertension and diabetes, rose for middle-agedadults over the past decade. With this surge in midlife deaths,overall life expectancy (starting at birth) in the U.S. declinedfrom 2014 to 2017, followed by a slight uptick in 2018.

"I'm struck by how well older adults are doing because itcontrasts with what's happening at midlife," said Anna Zajacova, anassociate professor of sociology and a population health expert atthe University of Western Ontario.

Why have older adults seen consistent life expectancy gains?

Much credit undoubtedly goes to medical advances and toMedicare, which extended health insurance coverage to all olderAmericans (age 65 and up) in 1966, improving access to care, saidScott Lynch, a sociology professor at Duke University and trainingdirector of Duke's Population Research Institute. By contrast, tensof millions of younger and middle-aged adults are uninsured orunderinsured.

Also, Social Security probably makes a difference by providing aminimum income — albeit one that hasn't kept up with rising costs ―for most older Americans.

"Thank the Lord for social insurance programs above age 65,"David Cutler, a professor of applied economics at HarvardUniversity, wrote in an email, while acknowledging that expertshaven't yet come up with definitive explanations for mortalitytrends in the older population.

But whether life expectancy trends at age 65 will remain on anupward trajectory is an open question.

In particular, "it's yet to be determined what impact theexplosion of obesity among prime-age adults will have when thispopulation passes age 65," said Timothy Waidmann, an economist andsenior fellow at the Urban Institute. "My guess is it won't begood. But that's a story yet to be seen."

KaiserHealth News is a nonprofit news service coveringhealth issues. It is an editorially independent program of theKaiser Family Foundation, which is not affiliated with KaiserPermanente.

Read more: 

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• Rising life expectancy boosts late-life risks forretirees
• Top 5, bottom 5 countries for life expectancy andwhere the U.S. ranks