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 National Center 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.