WASHINGTON — Deaths by drug overdose in the United States surged last year by more than 17 percent over 2015, another sign of the growing addiction crisis caused by opioids, according to a report released Friday by the Centers for Disease Control and Prevention.

Preliminary data from the 50 states show that from the fourth quarter of 2015, through the fourth quarter of 2016, the rate of fatal overdoses rose to nearly 20 people per 100,000 from 16.3 per 100,000. The C.D.C. had previously estimated that about 64,000 people died from drug overdoses in 2016, with the highest rates reported in New Hampshire, Kentucky, West Virginia, Ohio and Rhode Island.

Drug overdoses have become the leading cause of death for Americans under 50. In recent years, according to Dr. Robert Anderson, chief of the C.D.C. mortality statistics branch, the deaths have been driven by overdoses of synthetic opioids, mostly fentanyl, rather than heroin.

“The main message is the drug rate went up a lot again, and of course we’re worried about it,” Dr. Anderson said.