There were 63,938 drug poisoning deaths in 2016, up from 52,623 in 2015. That's a 21% increase. Out of this total, 55,071 were accidental deaths (86.1%), 5,102 were suicides (8%), 3,655 were "unknown intent" (5.7%), and 110 were "murder" (0.2%). In my analysis I mostly fixate on the accidental deaths. Suicides are tragic, but I don't think they count as "the drug problem." If we are trying to quantify the harm caused by drug use or misguided drug policy, I don't think it makes sense to count intentional deaths. Doing so is incredibly speculative ("But for his drug problem, this person would never have fallen into despair and ended his life.") This doesn't matter much, because the majority of drug poisoning deaths are accidental anyway. But I'm always a little bit put off by articles that cite the raw number without a breakdown by intent, or don't justify their methodology of adding together different things to get a bigger total. That's a warning sign. If you read anything that says there were "63,938 drug overdose deaths in 2016" without a breakdown, read the rest of it skeptically. This is similar to when people write about "gun violence" and include suicides when discussing the number of "gun deaths", except in the case of drug poisonings it's not quite as big a deal (suicides do make up a very large proportion of "gun deaths" on the other hand).
Some notable changes from 2015. Most significantly, "Other synthetic narcotics", a category that includes fentanyl and other very powerful opioids, continued its dramatic upward trend; it increased from 9,681 to 19,542. Heroin also increased, from 13,069 to 15,575. Benzodiazepines increased slightly from 9,002 to 10,898. Cocaine increased significantly from 6,945 to 10,588. "Other opioids", a category that includes most prescription opioid pills (Oxycontin, Vicodin, etc.) rose from 12,927 to 14,713. "Psychostimulants with abuse potential", a category including methamphetamine and prescription ADHD treatments like Adderall and Ritalin, increased from 6,082 to 8,036.
Most drug poisoning deaths are multi-drug interactions, so looking at the raw totals by substance will miss most of the story. That's the value of these raw data files. We can look at each individual death record and see what combinations of substances are killing people. (Don't worry, they are anonymized. When you die, the CDC doesn't publish your name and a list of the vices that killed you. So chill out.)
Take a look at the table below to see how important the "multi-drug poisoning" phenomenon is. For most classes of substances, a single-drug overdose is the exception rather than the rule. (Click to enlarge the data table. Sorry, I can't think of a more elegant way of sharing this in a blog post.)
Note that the totals don't match the text above; presumably the WONDER database is using a different filter. I am filtering the full set of death records from 2016 for deaths with a drug poisoning as the underlying cause of death. Some deaths may have a drug category listed as a contributing factor without being categorized as a drug poisoning; I think that explains part of the difference. Also, I am filtering for accidental deaths; the totals listed in the text above are showing suicides, undetermined intent, etc. All my tables and figures in this post are based on accidental deaths, excluding suicides, undetermined intent, and murder. (BTW, there were 2.75 million deaths from all causes in the US in 2016.) [12/31/2017: I edited this paragraph after posting. My original post neglected to mention filtering for accidents. Apologies for any confusion.]
I defined some of my own categories. "Any Opioids" includes heroin, "other opioids", "other synthetic opioids", and/or methadone. Most media accounts of "the opioid epidemic" count deaths this way, but I think this is wrong. It sums together two very different things. Heroin users are a very small number of people taking a very large risk, and prescription opioid users are a very large number of people doing something with very little risk. I included it because everyone else is doing it, but I should state for the record that this conflation is wrong and I don't care for it. "Prescription Opioids" is "other opioids" and/or methadone. I'm trying to capture "opioids commonly prescribed for pain." This might not be right, because a lot of the methadone deaths might be from heroin addicts on maintenance treatment. "Heroin or fentanyl" means the death had either heroin or "other synthetic narcotics" or both. I'm trying to capture the fact that a lot of "heroin overdoses" are due to fentanyl, and the coroner/medical examiner might write either one on the death certificate. But these are really part of the same problem. "Cocaine or Heroin" is exactly what it sounds like. I'm trying to capture the fact that someone who dies with one of these drugs in their system probably had a serious drug habit. So finding one of these in combination with something more innocent (like prescription opioids or benzodiazepines) probably means it wasn't an innocent slip-up by someone who is a legitimate prescription drug users. "Any alcohol" includes "ethanol", "Accidental poisoning by exposure to alcohol", and "alcohol, unspecified." (Why three categories for ostensibly the same thing? Are there specified uses for all of these categories? Or does the medical examiner just say "screw it" and pick one?)
Now take a look at what drugs tend to occur in combination with each other. (Again, click to enlarge; sorry for the terrible formatting.)
It's a lot to digest. What is so striking is the increase in the co-occurrence of cocaine and other synthetic narcotics. In the 2015 data 23% of cocaine-related deaths also included very powerful synthetic opioids like fentanyl. In the 2016 data this is up to 40%. Really, this co-occurrence is up across the board in 2016, for all substances. Someone without access to the detailed data (in other words, someone who is only looking at the summarized data from the WONDER database) might suspect that drug use across the board has increased, so we're seeing more overdoses from every category. That doesn't appear to be what's happening. Use rates haven't shot up in the most recent year, so a more likely story is that fentanyl and its analogues are infesting other drug habits. Fentanyl is very powerful, so it is easy for drug dealers to concentrate, conceal, and transport. But someone has to mix it into street drugs for retail. There is no guarantee that the person doing this understands what they are doing or knows how to dose it. The final consumer of the drugs often has no idea what they are getting. (Mike Riggs at Reason magazine totally called this one.) This is bad. Drug use is becoming deadlier without the total number of users growing.
Consider also "psychostimulants with abuse potential", where deaths increased from ~6000 to ~8000 in 2015 and 2016. Well, in that same one-year span the overlap with "other synthetic narcotics increased from 461 to 991. (As in, 461 deaths involved both in 2015 and 991 deaths involved both in 2016.) The overlap with "heroin" increased from 1058 to 1509. This is a point we have to be very careful about. One substance can drive up the mortality rates of other substances, even if use patterns for those other substances aren't changing. The multi-drug poisoning effect is an underappreciated thing. Benzodiazepines are a more extreme example. A pure "overdose" of benzodiazepines is incredibly rare, but if you look at the aggregated data from the CDC's WONDER database it looks like one of the most dangerous substances. (Again, see my post from a few days ago.) If any substance is driving up the overall mortality from drug poisonings, it will probably drive up benzodaizapine-related deaths. But it would be foolish to describe this as a "benzodiazepines epidemic." Just so for an "opioid epidemic."
I also think it's worth looking at the age distribution of these overdose deaths. Here are the average ages of the decedent for the most deadly substances or categories:
For most substances, the average age is around 40. This should leave a lot of readers scratching their heads, because we're used to sad stories about young people overdosing. For every 19-year-old heroin overdose victim, there's a corresponding 59-year-old. (I know, I know, distributions don't have to be perfectly symmetric. See the graph below for the details of the distribution.) In reality, drug use skews young, even though poisoning deaths skew old. I've written about that here and here. There are two possible interpretations of this pattern. One is that age is a huge risk factor in overdose death. That's perfectly believable. The more infirm you are and the more health problems you have, presumably the more susceptible you are to that one last straw. Another interpretation is that many of these deaths have nothing to do with drugs. They are mislabeled as "drug overdoses", perhaps because there was no other obvious cause of death. It's easy to imagine that some of these older individuals might die of a sudden cardiac arrhythmia, which may leave no obvious trace. If a family member mentions that the decedent was a drug user or if a toxicology screening turns up evidence of cocaine or heroin or prescription painkillers (which are used by ~1/3 of the population in any given year!), that might be a handy explanation for an otherwise inexplicable death. I've written about this here and here, with both posts drawing heavily on Karch's Pathology of Drug Abuse. It is incredibly difficult to establish the cause of anything, and it's important to remember that the "cause of death" on a death certificate is just some guy's educated guess. It may be the best possible guess under limited information, and in some cases it may be more obvious than in others. But don't dismiss the possibility that some of the recent increase in "drug overdose deaths" is due to miscoding and misattributing the cause of death.
Here are the age distributions for some of the most deadly substances:
Kind of surprising. At least it was to me. The distribution doesn't taper off until about the mid 60s or early 70s. (Age 999 is the code for "We didn't know the age of the decedent." Of course it's pretty rare. )
Here's my overall takeaway from the 2016 data. I feel like I called this. I didn't predict a sustained increase in poisoning deaths, but I did see the importance of fentanyl early on. The sustained increase in poisoning deaths is due to fentanyl and other even more powerful opioids. It's worth pointing out that this trend is entirely a result of the illegal status of recreational drugs. There is simply no natural demand for fentanyl (recreationally speaking anyway; chronic pain patients are often prescribed the fentanyl gel patch and some of them find it a godsend). Heroin users are afraid of it. The increase in cocaine-related poisoning deaths is sort of a smoking gun. I seriously doubt that cocaine users were telling their dealers to "Get me some of those hot shots!" I think it's far more likely that a roughly unchanged population of cocaine users were clandestinely given something they didn't ask for. It didn't have a label listing the various active ingredients and their dosages. It wasn't subjected to the kind of quality checks you see in legal markets. And people died.
In my previous work-ups of this data (for 2014 and 2015, linked to above), I stressed my skepticism of the raw numbers. Are things coded correctly? Are "heroin" deaths mislabeled? Should some of them be "other synthetic opioid" deaths? Are substances that were irrelevant to the death listed on the death record anyway? Were some of these actually drug poisonings at all? I think my skepticism holds up pretty well, too, but I should concede that there is little doubt that drug poisoning deaths really have been rising in the past few years. I don't want to adopt a stance of extreme skepticism, where we can't know anything about anything. But I think there is a lot to be skeptical of in the CDC's data. And even if we are to interpret it literally, there are extremely important details that typical media stories overlook.
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