Marijuana: It's like catnip for views here on Healthcare Triage. It's also one of the most controversial and complex subjects we cover. And, it's time for an update on what we know versus what we think when it comes to the drug. That's the topic of this weeks Healthcare Triage.

[Intro]

We've done previous episodes on pot, and what we know about it with respect to its medical use. But, the National Academies of Sciences, Medicine, and Engineering recently weighed in with pretty much the most comprehensive report I've ever seen on the topic. It's almost 400 pages long, and it covers just about everything you could want to know.

A bunch of experts from all over the country, including one who happens to have an office a couple doors down from me, reviewed something like 24,000 papers. We could spend the rest of the year going through their conclusions in detail, but we're going to try to boil this down to the high points. Pun intended.

As with our previous reviews, this report found that marijuana works to treat chronic pain in adults. This is such a no-brainer. Given the horrific outcomes from over-use and misuse of opioids, you'd think we'd be for anything in the toolbox that might help relieve pain without, you know, killing tons and tons of people. Marijuana happens to be one.

Marijuana works to improve the symptoms of nausea and vomiting in cancer patients. So, why do we deny them that? I can't tell you how many times people, including parents of kids who have cancer here in Indiana, have asked me why their kids suffering with cancer can't get relief. I wish I had an answer for them.

There also appears to be "conclusive or substantial evidence" that marijuana can improve multiple sclerosis spasticity. There's moderate evidence that marijuana can improve short-term sleep outcomes in people with obstructive sleep apnea, fibromyalgia, chronic pain, and multiple sclerosis. There's limited evidence that marijuana increases appetite for people with HIV/AIDS, that it improves the symptoms of Tourette's syndrome, and that it improves anxiety or reduced the symptoms of PTSD.

On the other hand, there's limited evidence, which means there's some, that marijuana does not improve symptoms associated with dementia, nor that it improved the intraocular pressure that comes with glaucoma. Also, there's evidence that it doesn't improve depressive symptoms in people with chronic pain or MS. Which is ironic, cause I hear that's one of the popular problems patients cite when they're seeking a prescription.

There's lots of stuff for which there really isn't any evidence for or against. These include treatment of cancers, irritable bowel syndrome, epilepsy, ALS, Huntington's disease, Parkinson's disease, dystonia, or schizophrenia.

Now, let's talk about some of the things people worry about. Let's start with cancer. There's moderate evidence that there is no association between smoking pot and getting lung cancer, or head and neck cancer. There is, however, limited, and I mean limited, evidence of a link between heavy pot smoking and non-seminoma-type testicular germ cell tumors. But, not any other types of testicular cancer, so take that one with a grain of salt.

There's no evidence, or not enough to say, whether there's a link between pot use and esophageal cancer, prostate cancer, cervical cancer, non-hodgkin lymphoma, pineal cancer, or bladder cancer. There's also no evidence, or not enough to say, whether smoking pot affects the chance of your kids getting cancer.

Heart disease: there's limited evidence that pot use can be associated with the triggering of a hearth attack, or to having a stroke or subarachnoid hemorrhage (or brain bleed). There's also a limited link to an increased risk of pre-diabetes. But, there's also a limited link to decreased risk of metabolic syndrome or actual diabetes, so I don't know. There's not enough evidence to comment on a link between chronic use and an increase risk of a heart attack, though.

Lung disease: there's substantial evidence of an association between smoking pot and worsening respiratory symptoms and bronchitis (from long-term smoking). But, there's moderate evidence for an association with use and acute improved airway dynamics and higher forced vital capacity. But, there's moderate evidence that those who stop smoking see improved respiratory symptoms. So, again, I don't know.

There's limited evidence for the risk of developing chronic obstructive pulmonary disease. There's no evidence, or not enough to comment, on the link between pot use and being hospitalized for COPD, or getting or worsening asthma. So, again, the jury's still out on the whole pot-respiratory system thing.

There's not much evidence to comment on problems with immunity. There's substantial evidence between the use of pot and an increase risk of motor vehicle crashes. There's moderate evidence that in states where it's legal, kids are more likely to suffer an injury from overdose. There's no evidence, or not enough to comment, on whether any of these things lead to actual death.

Smoking pot is associated with a lower birth weight in babies. There's limited evidence for pregnancy complications for mothers. There's not enough evidence to comment on much else about babies or outcomes.

There's moderate evidence that pot use can lead to acutely lower levels of learning, memory, and attention. There's limited evidence that it leads to worse outcomes like poor academic achievement, unemployment, lower income, or impaired social functioning.

Mental health gets complicated. There's substantial evidence that it seems linked to the development of schizophrenia. There's moderate evidence that in people with mental health issues, it can worsen symptoms, cognitive performance, and suicidal ideation and attempts at suicide. There's also substantial evidence that treatment for ADHD with stimulants is not a risk factor for using pot.

Those that use pot at a younger age and those who smoke cigarettes are more likely to progress to problem pot use. Those who use it more are more likely to progress as well. Some mental health issues do not appear to be a risk factor for problem use, nor is ADHD itself. Abusing other drugs is, though.

Let's recap. What do we know? Pot can be used to treat chronic pain, to treat nausea and vomiting in those with cancer, and to treat muscle spasticity in those with MS. Long term use can worsen bronchitis. Driving under the influence makes you more likely to get in an accident. You need to keep your pot away from your kids, and pregnant moms shouldn't smoke. It's also a risk factor for developing schizophrenia. We also know that pot works. It messes you up while you're high.

The truth of the matter, is that how you read this report is going to be clouded by how you feel about pot in general. Those that support its use, will say that there are clear benefits, and that the harms are way overblown by many. Those that oppose its use will say its benefits are limited, and look, it's harms are real.

We need to be clear, though, in saying that people use pot for various reasons. And, like other substances, people use it for benefits they perceive which may be greater than the harms they're taking on. That's a personal choice. As we've covered before, the harms are nothing compared to other drugs, and certainly much less than tobacco or alcohol abuse (and both of those are totally legal).

We also need to note that this is all for adults. Kids should not be using it recreationally. We also need to note that almost all the benefits are from studies of cannabinoid compounds, as opposed to smoked marijuana. So, we actually know very little about the therapeutic effects of smoked marijuana, which is almost entirely what's available in the marketplace. Conversely, almost all the harms literature focuses on smoking pot, and we know very little to nothing about edibles and other means of administration. Nor do we have any consistent manner of measuring level of exposure.

In that spirit, the report concludes by noting the challenges and barriers to conducting better research so that many more questions can be answered. These included the classification of pot as a Schedule 1 substance, which impedes research immensely. They include the difficulty researchers face in obtaining enough, and enough of a high-quality, pot with which to do research. No one wants to fund the work, either, which is an issue. We also need to use better methods and get more scientists interested in doing this important work.

[Outro]

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