Loading

Reefer Madness Continues: Can Marijuana Kill You?

  • by Mitch Earleywine February 28, 2014

    (Dr. Mitch Earleywine was elected as the Chairman of the NORML Board of Directors in February 2014)

    A recent headline reads: “Can Marijuana Kill You? German Scientists Say Yes.” The article focuses on a study of two (count ‘em, two!) young men who died while they had detectable levels of THC in their blood. I take a lot of pleasure in this kind of melodrama. If prohibitionists are stooping this low, we must really be frightening them. (It’s not completely pharmacologically ridiculous. Marijuana does increase heart rate. In fact, it can jack up heart rate almost as much as an espresso or energy drink. Maybe if you already had a weak heart and a coffee and a bong hit, well, something might happen.)

    But I want to point out that we should actually expect literally thousands of reports like this. We should hear about lots of people who have heart attacks on the same day that they commune with the plant. It’s not because cannabis causes heart attacks. It’s simple chance.

    I hate for my first blog as Chair of The Executive Board to be this nerdy, but I’ve been teaching statistics for more than 20 years. If that doesn’t make me a nerd, I’m not sure what would. But given how many people use cannabis daily and how many heart attacks occur in the United States, it’s actually a miracle that we haven’t heard about this kind of thing before. We also should expect to hear it a lot more often.

    According to the National Survey on Drug Use and Health, roughly 7,600,000 Americans (over age 12) used marijuana daily or near daily in 2012. In addition, the Center for Disease Control suggests that about 715,000 of us have heart attacks in a year. (Let’s assume those under age 12 are probably not grabbing their chests with a myocardial infarction too often.) In addition, let’s guess that the United States has about 280 million people over age 12. It’s hard to know the exact number, but that’s probably in the ballpark.

    With this in mind, we can predict how many people should have a heart attack the same day that they used cannabis simply by chance. That is, even if these two things had nothing to do with each other, we should expect some folks to have a heart attack the same day that they used cannabis just by accident.

    Okay. It’s going to get nerdy here, but this is comparable to asking simpler questions. If I had a dime and a nickel, I might want to know what the chances are that I’d flip heads on both. I flip heads 1 out of 2 times on average for the dime, for a probability of .5. Then I flip heads on the nickel 1 out of 2 times on average, also for a probability of .5. So the chances of flipping heads on both is .5 * .5 for .25. So we’d expect to get heads on both coins about 1Ž4 of the time. If I flipped both coins 100 times, I’d get around 25 pairs of heads. Note that there’s nothing causal here. The nickel doesn’t know what the dime did. It doesn’t want to be like the dime. It’s not that the dime caused the nickel to flip heads.

    So it’s the same deal for the cannabis-related heart attacks. If 7.6 million people use cannabis daily out of 280 million relevant Americans, that’s a probability of .0271. And if 715 thousand of 280 million have heart attacks, that’s a probability of .0026. Multiply these the same way we did with the probabilities for flipping heads (.0271 * .0026 = .00007). Now .00007 is a dinky number. If there were only 100 people in the country, we wouldn’t expect any of them (well, .007) to have a heart attack and smoke cannabis on the same day. But we’re talking about 280 million people here. So we’d expect .00007 * 280,000,000, = 19,600. That’s over 19,000 heart attacks.

    So the question isn’t, “How did these two guys die of a heart attack with THC in their blood?” It should be, “Where are the other 19,598 guys who should have had heart attacks with THC in their blood?” In fact, the absence of this many cannabis-related myocardial infarctions inspired my wife to ask, “Does cannabis protect the heart?”

    If we repeal prohibition, we’ll get to find out.

    Go AS, Mozaffarian D, Roger VL, Benjamin EJ, Berry JD, Borden WB, Bravata DM, Dai S, Ford ES, Fox CS, Franco S, Fullerton HJ, Gillespie C, Hailpern SM, Heit JA, Howard VJ, Huffman MD, Kissela BM, Kittner SJ, Lackland DT, Lichtman JH, Lisabeth LD, Magid D, Marcus GM, Marelli A, Matchar DB, McGuire DK, Mohler ER, Moy CS, Mussolino ME, Nichol G, Paynter NP, Schreiner PJ, Sorlie PD, Stein J, Turan TN, Virani SS, Wong ND, Woo D, Turner MB; American Heart Association Statistics Committee and Stroke Statistics Subcommittee. Heart disease and stroke statistics—2013 update: a report from the American Heart Association. Circulation. 2013 Jan 1;127(1):e6-e245.

    Substance Abuse and Mental Health Services Administration, Results from the 2012 National Survey on Drug Use and Health: Summary of National Findings, NSDUH Series H-46, HHS Publication No. (SMA) 13-4795. Rockville, MD: Substance Abuse and Mental Health Services Administration, 2013.

    68 Responses to “Reefer Madness Continues: Can Marijuana Kill You?”

    1. dontnosquat says:

      Taking another perspective, just because there was THC in their blood doesn’t mean it contributed to or caused their death. To cite: “the drug, known affectionately as weed, can be detected in the body for weeks and sometimes longer. How long it remains in the system depends on how often or how much marijuana the user has been smoking.” So where’s the smoking gun?

    2. darkcycle says:

      Let’s not forget, sudden death due to cardiac arrest occurs 325,000 times a year in the U.S. alone. That’s people without a cardiac history, or any symptoms. It would stand to reason some of those people would also simply by random chance, have ingested cannabis that same day. I’d say with numbers like those, it’s a stretch to believe you could find zero incidence of cannabis use. http://www.webmd.com/heart-disease/guide/sudden-cardiac-death

    3. Don B. says:

      I offer this tale of woe for the marijuana prohibitionists…a true story:

      I’ve been smoking pot for about 47 years, with breaks of months from time to time, but pretty consistently. Over the years I’ve noticed the development of some disturbing physical issues. They include wrinkles, hair loss, weakened vision, creaky joints, bunions, and I don’t care to stay up and party all night like I did in my 20’s. It follows logically that Marijuana must have caused these things to happen to me.

      Soooo, beware all you young people who are convinced that marijuana is not very harmful. I thought that too, and now I look like a much older man…and the same has happened to every other person I know who has smoked the devil’s weed for 40-50 years.

    4. Galileo Galilei says:

      “We also should expect to hear it (death from marijuana) a lot more often.” I’m sure we will, and the media will parrot it with soundbites.

      Thanks for your efforts on behalf of NORML, Dr. Earleywine.

    5. Patricia says:

      How did an article like that ever pass peer review? One assumes that all scientists are trained to understand statistics and probability. Shocking.

    6. Derek says:

      People also have water and food in their system when they die, so I guess we should all stop eating and drinking too. Unless they prove that the death was directly related to the THC in the blood it’s just a scare tactic.

    7. Anonymous says:

      The more important question would be: Is the level of THC today vastly different from what it once was in the 70s?

      There has been studies where the % of THC today than from the past is literally night and day. People with emotional instability can be worsened with potent marijuana, possibly causing psychosis and/or schizophrenic like symptoms.

      In other words, people are cultivating marijuana for the potency of getting high and not for medical purposes (which would be CBD to my knowledge).

      Just recently there was an article on Yahoo about ‘wax’ which is a super-concentrated form of THC residuals which according to them, is so potent that it will leave you high for more than a day (24 hours). God knows how much more damaging this may be to our ‘psyche’ let alone the fact that more studies are needed in this area. That is the endgame for marijuana’s future and possible legalization. Thank you~

    8. anony says:

      The more important question would be: Is the level of THC today vastly different from what it once was in the 70s?

      There has been studies where the % of THC today than from the past is literally night and day. People with emotional instability can be worsened with potent marijuana, possibly causing psychosis and/or schizophrenic like symptoms.

      In other words, people are cultivating marijuana for the potency of getting high and not for medical purposes (which would be CBD to my knowledge).

      Just recently there was an article on Yahoo about ‘wax’ which is a super-concentrated form of THC residuals which according to them, is so potent that it will leave you high for more than a day (24 hours). God knows how much more damaging this may be to our ‘psyche’ let alone the fact that more studies are needed in this area. That is the endgame for marijuana’s future and possible legalization. Thank you~

    9. Jh says:

      Fear of having a heart attack is more harmful to your health than smoking a joint.

    Leave a Reply