"Cannabis for IBD (Inflammatory Bowel Disease)"
“Medical marijuana: A panacea or scourge?”
For 5,000 years, cannabis has been used throughout the world
for medicinal purposes, even prescribed by American physicians
early on, a fact that’s often used by medical marijuana
proponents to justify modern medical applications.
But the field of old-timey medicine was fraught with
patent medicine snake oil nonsense, not to mention bloodletting
and other questionable and harmful remedies.
Skeptics criticize the medical marijuana movement
as the “medical excuse marijuana movement”,
insinuating that epileptic children and the terminally ill
are just being used as props to Trojan horse in the
legalization of recreational use, or to peddle outlandish claims
about “miracle cancer cures,” frustrating researchers
in the field who just want to get at the science.
For example, what about the therapeutic use
of cannabis for inflammatory bowel diseases
like Crohn’s disease and ulcerative colitis?
Conventional therapies mainly work by suppressing
the immune system to try to tamp down the inflammation.
Given the limited therapy options and known adverse side effects
from these drugs, often people suffering these diseases ended up
having to get inflamed sections of their bowels removed surgically,
so you can see why there’s so much interest in alternative approaches.
About one in six IBD patients who use marijuana say it helps
with their symptoms, so researchers decided to put it to the test.
Thirteen patients with inflammatory bowel disease were given
a third of a pound of marijuana to smoke at their leisure
over a period of 3 months, and they felt significantly better.
Now there was no control group, so you don’t know if
they would have gotten better anyway,
or what role the placebo effect may have played.
It’s like some of the studies of cannabis used
for pediatric epilepsy: response rates of over 30 percent,
seizure frequency cut in half in a third of the kids.
That’s amazing until you realize you can sometimes get
the same kind of amazing response giving kids nothing,
giving them a sugar pill placebo.
That’s why it’s critical to do randomized, double-blind,
placebo-controlled trials, but there weren’t any
on cannabis and IBD until 2013.
Twenty-one patients with Crohn’s disease for which nothing
seemed to help, so they randomized them to either
smoke 2 joints a day of real pot or a look-alike placebo pot.
And 90 percent of the subjects in the cannabis group got better,
compared to only 40 percent in the placebo group.
Here's a graph of their symptom scores:
no big change in the placebo group over the two-month study,
but the cannabis group like cut their symptoms in half.
They acknowledge that long-term cannabis use is not without risks,
but it may be a cakewalk compared to the potential adverse
and even life-threatening side effects of some of the
more powerful conventional therapies, so the study was heralded
as offering “High Hope” for digestive disorders.
Now the study was funded by a medical marijuana advocacy organization,
in fact the main supplier in the country, and so there may have been
expectations placed on the subjects on how much better this stuff
is going to make them feel
(in other words a set-up for the placebo effect).
But they controlled for that, right?
Those getting the real stuff did significantly better
than those randomized to get the placebo pot.
But wait a second. The whole point of a placebo
is to be indistinguishable from the real thing,
so the subjects don’t know which group they’re really in.
How do you do that with a psychoactive drug?
You can’t, which is the problem. They tried to hide
which group people were in by recruiting only patients
who never tried pot before in hopes that they wouldn’t notice,
but of course most of them did.
So what we’re left with is basically another unblinded study.
They asked them a bunch of subjective questions, “how you feelin’?”,
and those who mostly knew they were taking the drug
said they were feeling better.
There was no change in the objective lab values, like CRP,
a sign of inflammation and so maybe the marijuana is just
masking symptoms without actually affecting intestinal inflammation.
Another indicator that cannabis may not be affecting the course
of the disease itself is how quickly the symptoms rebounded.
Two weeks after the study ended the cannabis group
was right back up to where they started.
So, no difference in objective inflammatory markers,
and given the rapid rebound it seems more plausible
that cannabis ameliorated the symptoms of Crohn’s disease,
rather than actually modulating the disease itself.
Okay, yeah, but the symptoms are terrible.
A reduction in pain is a reduction in pain.
From the point of view of the patients, a marked symptomatic
improvement and ability to resume normal life is not trivial,
whether or not the inflammation persists, unless, of course,
cannabis somehow made the disease worse in the long run.
This survey study published the following year found that
cannabis provided that same immediate symptomatic relief
but was associated with a worse disease prognosis over time.
Patients with inflammatory bowel disease reported that
cannabis improved their pain, cramping, and diarrhea,
but use for more than 6 months in Crohn’s patients
appeared to be a strong predictor of them ending up in surgery,
5 times the odds of them ending up under the knife.
Now there’s two possible explanations for this.
It’s quite possible that it was the increased severity
that led to the cannabis use and not the other way around.
But the alternative explanation is that cannabis use may worsen
the prognosis, leading to greater surgeries and hospitalizations.
That’s why we really need prospective clinical trials
where we follow people over time to see which came first,
but until then maybe we should consider
cannabis use in IBD as potentially harmful.
Not just to err on the side of caution, but there was
this other study on hepatitis C patients that found
that daily cannabis use was associated with nearly 7 times
the odds of worse liver fibrosis, which is like scar tissue.
And so hey, if cannabis really does make fibrosis worse,
then that could potentially explain why cannabis users with IBD
may be more likely to end up on the operating table.