SCOTT SIMON, HOST:
The opioid crisis is thought to have started in the late 1990s when physicians began to prescribe opioids more widely. But a new study shows that deaths from drug overdoses have been growing exponentially since the 1970s, long before the rise in opioid prescriptions. NPR's Rhitu Chatterjee has the story.
RHITU CHATTERJEE, BYLINE: Drug overdose deaths began to be recorded as their own separate category in 1979. In the new study, researchers at the University of Pittsburgh analyzed these deaths from 1979 all the way to 2016. Donald Burke is the dean of the School of Public Health at the University of Pittsburgh and an author of the new study.
DONALD BURKE: We were looking at the overall long-term patterns of mortality from overdoses in the United States.
CHATTERJEE: This included overdoses of all kinds of drugs, from cocaine and methamphetamine to prescription opioids and heroin.
BURKE: I expected that the overall number of deaths would vary substantially from year to year and go up and down depending on the changes in the availability of drugs or the changes in the demography.
CHATTERJEE: Now, the overdose deaths for each individual drug did indeed vary over time. For example, for cocaine overdose deaths, there was a brief spike in the mid-2000s. And they've been on the rise again in recent years. But when all the drug overdose deaths were clumped together, the numbers revealed something surprising. The deaths have been rising steadily, as if part of a single, worsening epidemic.
BURKE: There was a continuous growth of the epidemic that started at least 40 years ago.
CHATTERJEE: What this means, Burke says, is that there must be some common underlying drivers of all these different drug overdoses. One of those drivers, he speculates, has to do with the technology and economics of drug production.
BURKE: Increased efficiencies of synthesis, lower prices, higher purity - all of the things that increase the availability or supply of drugs.
CHATTERJEE: That's also made drugs more dangerous in recent years, says Kate McHugh, a psychiatrist with McLean Hospital and Harvard Medical School who wasn't involved in the new study.
KATE MCHUGH: The degree of fatality or the degree of potency of these drugs is going through the roof.
CHATTERJEE: And the new study, which was published in this week's journal Science, also shows that a growing number of people who died in recent years were not using one but multiple drugs. McHugh says another common factor driving substance use and therefore overdose deaths is mental illness.
MCHUGH: We know people with psychiatric disorders are more likely to be prescribed an opioid, are more likely to struggle with pain, are more likely to misuse opioids.
CHATTERJEE: Improving access to mental health care, she says, would not only help us tackle the ongoing opioid crisis but prevent future waves of substance use disorders.
MCHUGH: We have to be careful not to play whack-a-mole with this type of crisis, where we focus too much on what is sitting in front of us now and not think about some of the historical patterns.
CHATTERJEE: Because if there's one thing that history shows - is that the trends of overdose deaths have only worsened with time. And there will be likely another epidemic in the future.
SIMON: That was NPR's Rhitu Chatterjee. Transcript provided by NPR, Copyright NPR.