The U.S. death rate is on the rise for the first time in more than 15 years, with life expectancy for a baby born in 2015 dropping slightly, the government reported Thursday.
In a trend that's worrying experts, the nation's death rate — or the number of deaths for every 100,000 U.S. residents — rose 1.2 percent from 2014 to last year, the first noteworthy uptick since 1999.
"The increase is significant," Jiaquan Xu, the report co-author and an epidemiologist at the CDC's National Center for Health Statistics, told TODAY. "It's a widespread increase in terms of causes and in terms of gender."
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The death rate increased for white men, white women, and black men. All of the major diseases were more lethal, except cancer. Deaths from suicide and accidents were also up.
"Everybody in this country wants to live a long, healthy life, so we should be very concerned," said Dr. Christopher Murray, director of the Institute for Health Metrics and Evaluation at the University of Washington.
"We've been fortunate to experience steadily improving health in the U.S. ... and we should be very concerned if that trend is going to reverse."
At this point, the CDC doesn't know what caused the changes, with a more detailed report to be released next year, Xu said. Murray believes part of the reason is obesity, which is linked to cancers, heart disease and diabetes.
But other experts disagreed. Dr. Peter Muennig, professor of health policy and management at Columbia University Mailman School of Public Health, said obesity rates aren't increasing that heavily to explain the changes.
"Why is it that Americans' health has started to decline? We don't have concrete answers," Muennig said.
This troubling trend has been widely expected because of the ongoing opioid epidemic and increases in suicide, traffic deaths, and infant mortality in recent years, added Dr. Guohua Li, director of the Center for Injury Epidemiology and Prevention at the Columbia University Mailman School of Public Health.
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Meanwhile, life expectancy for a baby born in 2015 dropped one-tenth of year — from 78.9 years to 78.8. That may not sound like much, but Xu called it "a big deal." Life expectancy can fluctuate among men and women, but it hasn't declined for the total U.S. population since 1993, Xu said.
Muennig called the development huge.
"Historically, life expectancy increases," Muennig said. "Barring any major public health catastrophe, it's unusual to see a decrease in life expectancy. You should be seeing an increase from year to year."
He was also not encouraged by the drop in cancer deaths, noting that experts have been expecting much larger drops since cigarette smoking has declined dramatically among Americans.
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The 10 leading causes of death in 2015 were the same as 2014 and accounted for 74 percent of all deaths in the U.S. The year-over-year age-adjusted rate changes are in parentheses.
- Heart disease (up 0.9 percent)
- Cancer (down 1.7 percent)
- Chronic lower respiratory diseases (up 2.7 percent)
- Unintentional injuries, like accidents (up 6.7 percent)
- Stroke (up 3 percent)
- Alzheimer's disease (up 15.7 percent)
- Diabetes (up 1.9 percent)
- Influenza and pneumonia (no change)
- Kidney disease (up 1.5 percent)
- Suicide (up 2.3 percent)
The Alzheimer's statistic may be the most startling, but Murray doesn't believe it reflects a real trend. Rather, he thinks doctors are now much more likely to list Alzheimer's as the cause of death than they were in the past.