By Nathan Seppa
Since the early 1960s, average life expectancy in the United States
has grown steadily. But this overall gain has disguised the fact that in some
locales the upward trend stalled in the 1980s and 1990s, a new study finds.
Women in particular have lost momentum. In 180 U.S. counties, their life
expectancy decreased during those decades.
“The fact that the health of a pretty large part of the population is
stagnating or getting worse is a pretty unusual thing,” says study coauthor
Majid Ezzati, a population researcher at the Harvard School of Public Health in
Boston. It’s a
trend that runs counter to other Western countries, he says.
Women still live longer than men. From 1961 to 1999, the average life
expectancy for men in the United
States increased from 67 to 74 years. For
women, it grew from 74 to 80 years.
That’s good news, but the first half of that span tells a different story from
the second. While men gained four years over the first half and women gained
five, their situations reversed in the 1980s and 1990s, when men added three
more years of life while women tacked on just one.
What’s more, the trend to live longer stopped or reversed in many parts of the
Deep South, Appalachia, Mississippi
Valley, Great Plains and Texas
in the 1980s and 1990s, Ezzati says. To a lesser extent, the trend stalled in
the Midwest and other parts of the country.
During that time frame, women’s life expectancy flattened out in nearly 1,924
counties and decreased in 180 others. Men saw it stall in 427 counties and
decline in 11, the researchers report in the April PLoS Medicine.
The researchers used data compiled by the NationalCenter
for Health Statistics and the U.S. Census. Since counties are the smallest
geographical unit for which death rates are available, the scientists
calculated each county’s average life expectancy over the decades. This allowed
them to determine whether a county had kept pace with the national average, had
exceeded it or had fallen behind. Contiguous very small counties were combined
for calculation purposes.
“The researchers have identified that there are actual pockets — geographical
areas — in the United States that have experienced certain periods in which
people fared quite poorly,” says epidemiologist Sam Harper of McGill University
in Montreal, who didn’t participate in this study. “But the long-term trend is
still quite positive.”
Meanwhile, the data confirm that the United States has become a country
in which life span is scarcely affected by infectious diseases, with only HIV
having a significant impact. Instead, the prime factors shortening lives are
high blood pressure, obesity and smoking, Ezzati says. Over the long run, these
lead to heart problems, stroke, diabetes, emphysema and lung cancer.
While women still live longer than men, women’s slowing gains in recent decades
might be due to more smoking during this four-decade period, Harper says. “The
smoking epidemic has already gone through men in some ways,” he says. Its
impact on women might still be showing up, even though many women have since
quit and fewer are starting.
Millions of people are also uninsured in the United States. “Quality of health
care services may be part of the story,” Ezzati says, with some risk arising
from fewer blood pressure checkups and less regular follow-up.
