NEW YORK — Cocaine deaths have been rising in the U.S., health officials said Thursday in their latest report on the nation’s deadliest drug overdose epidemic.

After several years of decline, overdose deaths involving cocaine began rising around 2012. And they jumped by more than a third between 2016 and 2017.

The increase at least partly reflects trends in deaths from heroin, fentanyl and other opioid drugs. Many overdose deaths involve several different drugs. The CDC researchers found that nearly three-quarters of the deaths involving cocaine in 2017 were among people who had also taken opioids.

But deaths involving cocaine alone also increased, said Lawrence Scholl of the Centers for Disease Control and Prevention, one of the study’s authors.

The researchers did not look at why cocaine deaths have been increasing.

Ohio Was the State With Highest Cocaine Death Rate

Health officials say about 70,000 Americans died of drug overdoses in 2017. Nearly 48,000 involved at least one type of opioid. About 28,000 deaths involved fentanyl or some other kind of synthetic opioid, 15,500 involved heroin, and 14,500 involved prescription opioid painkillers.

Just under 14,000 involved cocaine, according to the new report.

Ohio was the state with highest cocaine death rate, but the largest relative increases were seen in Wisconsin and Maryland.

The new report goes through 2017, the last year for which complete statistics are available.

Some preliminary data from CDC suggests that deaths from cocaine continued to rise early in 2018 but may have leveled off last summer. However, “this is provisional data and this may not reflect what we see when we get the final data” for 2018, cautioned one of the CDC other authors, Mbabazi Kariisa.