From Cancer to Eyesight, is There Anything Cannabis Can’t Cure?

Marijuana Exposure Prenatally Helps Eyesight

This week I read an article on The Metro online with the title of: ‘Babies Exposed to Marijuana in the womb actually have better eyesight’ and I shuddered at the sheer thought of how poor a study this would have actually been. Not all too shockingly this was shared all over Facebook timelines by stoners and the ilk, I am assuming none of which have read the newspaper article or even tried to access the study (which is actually open access, so its free. There’s no excuse for ignorance here). I imagine thousands of cannabis users and pro-cannabis folk rejoiced at the new information, cannabis can cure cancer and now it helps with eyesight in children if you consume it whilst pregnant. How come this isn’t legalised? Well, Read on. 

The Study and the Media

The study is an open access study published in The Journal of Scientific Reports entitled: Prenatal Exposure to Recreational Drugs Affects Global Motion Perception in Preschool Children. This article was picked up heavily by the Daily Mail and the aforementioned metro, heralding the study, stating that babies which are exposed to cannabis have better vision by the age of 4. In the study, they tested the meconium from the children and tested for the presence of drugs. Essentially, they tested the eyesight of children who had known prenatal exposure to drugs at the age of 4.5 using the global motion perception. They found that those that had been exposed to alcohol and cannabis prenatally had better eye tracking than those of the control. Let’s look further into why none of this is as accurate as it appears and why the media are completely wrong:

·      Visual processing skills are developed at different rates and through different techniques (PDF). The old nature V.S. nurture adage, how do they know that the parents haven’t spent more time helping their children develop than the control group? Y’know, had they actually had a reliable control group.

·      The participants (n=165), were split into two groups control V.S. study. Like me, you would think that the ‘control’ would be those that haven’t had a prenatal exposure to drugs? You’d be wrong, this line is straight out of the article:

Participants in the IDEAL study were recruited to two groups on the basis of prenatal methamphetamine exposure (methamphetamine exposed vs. controls). Many mothers of methamphetamine-exposed children were poly-drug users. The control group included children who were also exposed to a range of drug combinations with the exception of methamphetamine as well as non-drug exposed children.

So, the control has been exposed to drugs, just not methamphetamine. That seems like an excellent measure. How do they know that one of the other drugs being consumed is making the eyesight worse and that the methamphetamine isn’t actually affecting the eyesight at all? Simple, they don’t, because they don’t have a proper control group. Even more, their control group only encompasses 15% of their sample group. So they have 165 subjects, 25 of which are the sample group and 140 are the analysis group. That should make for a highly unbiased statistical analysis….

·      The statistical analysis carried out compared the relationship between cannabis, nicotine, alcohol and methamphetamine on motion perception. As an add on, they assessed the relationship between the extent of drug exposure of cannabis and motion perception. Meconium analysis is an entirely feasible method for drug analysis. However, it doesn’t detect all drugs. Drug misuse has to occur in the 2^nd and 3^rd trimesters to be detected in the meconium, this study does not address this fact and includes the first trimester as a measure. It also doesn’t take into account the unreliability of the subjects’ recollection. For instance, the subjects could have taken multiple doses of drugs in one night, or even abstained but thought they had consumed more. Even more, from working in a drugs lab, I know that they may very well not be consuming what they think they’re consuming (with the exception of cannabis, I mean, that’s pretty obvious).

The alcohol and marijuana use was determined by a subset of questions, such as how much was consumed and categorised into ‘light, moderate and heavy’. Most people who drink at home don’t measure their drinks – so one drink could be classed as light but it could be stronger than the average. Which brings use to the concentration, surely that plays an effect. If someone consumes 3 vodkas, lets assume they’re measured amounts, then they have consumed more alcohol than someone who has had 3 alcopops for example. Only 40% of the subjects had been exposed to cannabis. So the media are now reporting on an article that is comparing 66 subjects to 25. More then doubling the subject group over the control more than doubles the statistical outcome of the study.

Impact Measures

The impact factor is possibly something that should be taken into account with these type of articles. Now, this is much debated in the scientific community as to whether an impact factor has any credence, in my opinion, it does. The impact factor is the frequency in which an average article within a journal has been cited for a particular year. This is used to measure the importance of a journal in its respective field. Articles that are contained to more prolific journals are more likely to be trusted due to the more rigorous peer review that the article receives. So, is the journal a well established journal with a high impact factor such as Nature (which for reference has an average impact factor of 41)? No, we are looking at The Journal of Scientific Reports with an impact factor of….5.

Conclusion

This study is the height of inaccuracy and what is incorrect with studies published in these low impact factor journals. Comparing 140 people to a control group of 25 is beyond ridiculous, as you can imagine, any differences will be prolifically highlighted in the statistical analysis, which is exactly what these studies rely on for publishing. As for the media, well they do what they normally do. Don’t read the study, just get someone which as high-school GCSE in science to write the study, as they ‘know enough science’ to be scientific reporters, right? No, the impact of these articles could be phenomenal on people who already have their preconceived notions about cannabis. I feel like I have to say this; the results of this study should not (and, unfortunately, have been) be extrapolated to mean that cannabis and alcohol consumption whilst pregnant has any benefit to foetal development. Again, tracking is something that can be improved by nurturing a child there is very little evidence here to indicate that drug consumption has helped at all. 

 

Previously I wrote an article on here about how cannabis cannot be and is not used to cure cancer, if you are a pro-cannabis aficionado who believes that it should be legalised on this basis, I suggest you read.