CBD Maybe not a Miracle Cure for Childhood Seizure Disorders

One of the stories that got a lot of media time during the fight to make recreational marijuana a legal reality was the one of Haleigh–a young girl who, prior to adopting a CBD regimen to treat her seizures, was having 200 episodes a day and now is closer to 10. That is a huge success. We read a lot out here about all the families that are moving to Colorado to obtain marijuana for their children’s seizure treatment. I would say that, aside from treating chronic pain…especially chronic pain in association with chemotherapy…marijuana’s miraculous power in treating seizures in children is the driving narrative of why marijuana should be reschedule, why every state without a medical marijuana law should get one, and why recreational marijuana should be far more widespread.

I have no doubts that Haleigh’s story is a true. In fact, a recent study (abstract here) found that 33% parents of children taking CBD reported their  children’s seizures drop by half. That’s huge.

However, that same study found that 44% of children taking CBD were suffering negative health outcomes from the treatment including (and this is important) increased seizures.

In a more objective measure of seizure-related brain health, only 3 of the children in the study showed any actual improvement (which indicates that some portion of those 33% of children who saw their seizure decrease by half, may have have been over-reporting the benefit, or may be operating under some placebo effect).

In any case, those last two points are crucial and they will no doubt be completely, and tragically, overlooked.

Medicine is weird; it works for whom it works. The way we determine if a medicine works is to get two groups. Individuals are randomly selected into one of the two groups. One group receives the treatment, the other receives a placebo. If possible, even the administrators don’t know which individuals are receiving which medication and which the placebo. Then we look for improvements in both groups. For various reasons, some people in both groups will get worse and some people will get better and some people may see no change in their condition at all. Ideally we will see more people get better in the medication group and less people getting worse. In either case, the differences observed within each group will be compared to the differences observed in the other group to determine if those change are “statistically significant.” That’s a real rough description of the “double blind, randomized, placebo-controlled, trial.”  Basically if the improvements in the medication group are better than the natural improvements seen in the control group, researchers conclude that the medicine “worked.”

But something peculiar happened up there. Something that researchers know about but doesn’t always get translated out. The medicine didn’t seem to have any effect at all on some people. And worse, some got worse.

Some of those differences might be chalked up to an inability to precisely measure changes in the condition. We tend to think of illness as a thing you either have or you don’t, rather than thinking of it in terms of how much of it you have. So it might be that very minor improvements in condition were beneath a threshold where those improvements were observed and reported to researchers. It’s also possible that declining condition in the medicine group would have been more pronounced had the medicine not been present.

But it’s also entirely possible that the medicine helped some people in the medicine group and harmed other people in the medicine group. Humans are all different. Diseases manifest differently in different people, medicines react differently to different people. So when we claim that a medicine “worked” it’s not always entirely clear what is meant. So the medicine works for whom it works and not on anyone else. Ideally, we would give medicine that works only to people that it works on…and maybe even prescribe medicine that “doesn’t work” to the people it works on as well even if it doesn’t “work” any better than chance at the group level.

I’m not saying that the story linked here proves that marijuana is a crappy medicine for children with seizures. It’s entirely possible that marijuana is very good for some children, and maybe not quite as good and possibly harmful for others. The problem is that the rhetoric of these “miraculous” cures is problematic. Parents desperate to find any cure for their children may overlook problems with marijuana in their child, they may see signs of improvements that don’t exist. And worse, they may forego other, effective, treatments while hoping that the marijuana miracle works out.

I think this is an area where we definitely need more research. And marijuana is cheap and, compared to many traditional treatments, safe. So I’m glad that it’s available for parents to try. But I also wish that the conversation we were having didn’t involve the word “miracle” quite so often. And that the potential for no- or bad outcomes was more appreciated.