Minnesota has seen proportionately fewer opioid-related deaths than the rest of the nation and a decline in fatal heroin overdoses, but the state’s progress has been negated by a surge of drug use involving potent synthetic drugs such as fentanyl.

That mixed news emerged Friday in a report by the U.S. Centers for Disease Control and Prevention, which found that the nation is still struggling with an opioid overdose crisis — but with a new class of drugs fueling a problem that first emerged two decades ago.

The age-adjusted rate of opioid overdose deaths increased from 13.3 deaths per 100,000 Americans in 2016 to 14.9 deaths in 2017 — despite nationwide criminal justice and public health campaigns that at least leveled off the number of deaths involving common prescription painkillers, and illicit heroin.

“Fentanyl is, in a certain sense, outpacing heroin in terms of what is the most lethal illicit opioid,” said Dr. Chris Johnson, a Twin Cities practitioner who led a recent state opioid prescribing work group. “The rate of increase in the last two years has just been staggering.”

Minnesota was one of five states to see a significant decline in its rate of heroin deaths, but its overall opioid death toll nonetheless increased from 396 in 2016 to 422 in 2017, according to the CDC’s figures. Deaths in the state related to synthetics such as fentanyl, which is 50 to 100 times stronger than common morphine painkillers, rose from 99 to 184 in the same time frame.

“The drug overdose epidemic continues to evolve,” said Dr. Debra Houry, director of the CDC’s National Center for Injury Prevention and Control.

While fentanyl exists in legal lozenges, injections and patches for management of severe pain, the forms linked to many of the deaths are compounded in China and other countries and sold illegally in the U.S. The 2016 death of Minnesota pop icon Prince was attributed to counterfeit pills that were made to look like Vicodin painkillers but contained fentanyl.

Law enforcement authorities in Minnesota are confronting that side of the opioid problem by seeking homicide charges against dealers who give out fatal doses of fentanyl.

Johnson has been a vocal critic of his own colleagues, and how they were influenced by pharmaceutical marketing messages over the past two decades to use opioids to overtreat pain. And he wasn’t ready to let them off the hook now that illicit synthetic drugs are causing more of the deaths.

“Four out of five users of heroin began with prescription pills,” he said.

While deaths from prescription opioid painkillers leveled off at 195 in 2016 and 2017, Johnson noted that is still higher than death figures a decade ago. And doctors have known for several years about the hazards of overprescribing.

Johnson’s state work group recommended new limits last year for the strength and amount of opioid pills given to patients for pain after surgeries or hospitalizations. It also discouraged the unproven use of opioids for management of long-term chronic pain.

However, Johnson said there is a population of pain patients who are already dependent on opioids, and who would probably just turn to dangerous illegal drugs if doctors cut off their prescription supplies now.

“Forced reduction in dosing can be an unsafe proposition,” he said. “That is a misfortune that we created.”