THURSDAY, Dec. 21, 2017 (HealthDay News) -- The opioid epidemic continues to chip away at the average American life span, federal health officials reported Thursday.
Life expectancy declined in the United States for the second year in a row in 2016, driven downward by fatal drug overdoses in young and middle-aged adults, according to a new report from the U.S. National Center for Health Statistics (NCHS).
If the trend holds, "we could have more than two years of declining life expectancy in a row, which we haven't seen since the influenza pandemic of 1918," said Bob Anderson, chief of the NCHS Mortality Statistics Branch. "We haven't seen three years in a row since then, and that was a century ago."
Average life expectancy for the U.S. population in 2016 was 78.6 years, a decrease of one-tenth of a year from 2015, the researchers said. That followed another one-tenth of a year decline between 2014 and 2015.
Drug overdose deaths increased 21 percent in 2016, and appears to be the main cause for the decline in life expectancy, Anderson said.
"We need to pay attention to this," he said. "This is something akin to what we saw with the HIV epidemic, but it's gone well beyond what we saw with the HIV epidemic in terms of magnitude."
There were 63,600 overdose deaths in 2016, Anderson said. HIV deaths topped out in the mid-1990s at around 40,000 deaths per year.
The continuing decline in life expectancy is "really alarming, and really demonstrates the size and severity of the opioid epidemic and our national addiction problem," said Lindsey Vuolo. She is associate director of health law and policy with the National Center on Addiction and Substance Abuse.
Drug overdose deaths have been increasing for the last decade or so, and that increase has been accelerating in recent years, Anderson said.
But until recently those deaths have not affected overall life expectancy because of accompanying declines in heart disease-related deaths, he said.
"While the increase in drug overdose mortality has been quite substantial and very concerning, it hasn't impacted the overall picture in terms of mortality," Anderson said.
However, heart-related deaths have recently started to level off, while drug overdose deaths continue to escalate.
"Now with this leveling off, over the last couple of years we're seeing that quite substantial impact on life expectancy," Anderson said.
Adults between the ages of 25 and 54 had the highest rates of drug overdose deaths in 2016, at around 35 per 100,000 people, the researchers found. Overall death rates between 2015 and 2016 increased for younger age groups and decreased for older age groups.
"Life expectancy is declining because more young people are dying, while older people are living longer," said Vuolo. "Life expectancy of youths should not be shrinking, especially not in the United States, and that is attributable to overdoses. The overdose death rates increased in the same age groups that experienced increases in the death rates."
The states with the highest drug overdose rates are the ones hardest hit by the opioid crisis -- West Virginia (52 deaths per 100,000), Ohio (39.1), New Hampshire (39), the District of Columbia (38.8), and Pennsylvania (37.9).
Synthetic opioids like fentanyl continue to make a mark on drug overdose deaths. The rate of overdose deaths involving synthetic opioids doubled between 2015 and 2016, from 3.1 to 6.2 deaths per 100,000, according to the report.
Vuolo noted that the death rates for most chronic diseases either remained stable or decreased, including heart disease, cancer, chronic lower respiratory disease and diabetes.
On the other hand, the rates for overdoses, Alzheimer's and suicide all increased.
"While we're doing a good job of treating chronic physical diseases, we're not making the same progress with chronic brain diseases," Vuolo said. "We really need to be doing more to treat addiction as a chronic disease.
"It's important to remember these deaths are preventable," she continued. "If we start treating addiction the way we treat other diseases, with a health-based approach funded at a level commensurate with the size and scope of the problem, we will overcome this crisis."
The decline in life expectancy even occurred despite an overall decrease in U.S. mortality. The death rate for the entire U.S. population decreased by 0.6 percent from 733.1 deaths per 100,000 population in 2015 to 728.8 deaths per 100,000 in 2016.
The 10 leading causes of death in 2016 remained the same as in 2015, but accidents became the third leading cause of death, behind heart disease and cancer. Drug overdoses are counted as accidents, and they are what drove accidents into the third slot, Anderson said, while chronic lower respiratory diseases dropped to fourth place.
The report, Mortality in the United States: 2016, was published Dec. 21.
For more on the opioid epidemic, visit the U.S. Centers for Disease Control and Prevention.