CUD or effects of smoking? 10 Things to Consider – Cannabis | weed | marijuana

Is “Cannabis Use Disorder” (CUD) causing all sorts of perioperative problems, or is it the effects of smoking? A recent article published in JAMA Surgery magazine took a look.

Here was her question.

“Is Cannabis Use Disorder Associated with an Increased Risk of Perioperative Complications and In-Hospital Mortality After Major Elective Hospital Procedures?”

Note the assumed reality that CUD exists. They refer to the ICD-10 definition. But we are not here to criticize the results of this work.

It may well be that long-term, randomized control studies demonstrate a physiological conflict between surgery and cannabis.

Instead, it’s the paper’s methodology that leaves us wanting. Just like the media coverage. A headline from CNN reads, “Excessive marijuana use leads to surgical complications and death, study finds.”

Does the study say so? And if so, is that a valid assessment? Here are ten things to consider about the study methodology.

Ask yourself: is CUD causing these complications, or is it the effects of smoking?

CUD or effects of smoking? #10 Data Source

THE CANADIAN PRESS/Joe Mahoney

This study used retrospective data from the National Inpatient Sample (NIS). We doubt the accuracy (or completeness) of this information resulting from US inpatient billing.

Furthermore, the authors of the study have no control over this data collection. Crucial information is missing, leading to bias. Namely, is it CUD or the effects of smoking?

#9 Selection Bias

Admittedly, the study authors focused on major elective surgeries in adults between the ages of 18 and 65. However, the dependency on the NIS database leads to a selection bias. It includes only hospitalizations and excludes outpatient surgeries.

There is also no information on the shipping methods. Clogged arteries, stroke, kidney damage, blood clots, infections, and even hospital deaths have been linked to “cannabis use disorder.”

CUD or effects of smoking? #8 Covariate Selection

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are covariates Variables that affect a response variable but are not of interest to the study. The selection of covariates in this study is based on previous literature. Did the authors omit important confounding variables? Whether intentional or not?

#7 Propensity Score Matching

Researchers use propensity score matching to reduce bias. However, this technique requires that you know all the relevant disruptive factors. That is, a variable that affects dependent and independent variables and causes a false association.

If an unmeasured confounder is present, this propensity score matching process will not resolve it. Remember the basic premise of the study: does CUD cause perioperative complications?

Is it CUD or the effects of smoking?

CUD or effects of smoking? #6 Selection Distortion (Again)

In this study, “CUD” patients and the “unexposed” group are compared in a 1:1 ratio. However, the authors excluded some mismatched patients from the unexposed group from the analysis. Why?

This clearly introduces selection bias and affects the overall results. The study authors later say they performed a “sensitivity analysis,” but admit it resulted in a loss of transparency.

In other words, in this study, the matched cohort groups were compared side-by-side. But they excluded patients who did not match their bias.

You may see the validity of the question: is it CUD or the effects of smoking?

#5 Pointless statistical analysis

This study uses multiple statistical models including logistic regression and negative binomial regression. Each with its assumptions and limitations.

But what about details about missing data? What about the mismatched patients from the non-exposed group? Why ignore variables of interest?

CUD or effects of smoking? #4 Other limits

Is it CUD or the effects of smoking? The data doesn’t say that. The authors assume that it is the former. But even if it were true, it would only be between January 2016 and December 2019.

This study has found nothing universally true and scientific.

#3 Other disruptive factors

Unmeasured and unknown factors render the observed correlations of this study practically unusable. Again, we don’t want to say that there is no conflict between smoking cannabis and having surgery. However, this is not the study that confirms this.

The most blatant example is the source data for the “CUD” patients. Nowhere does it address how severe they felt their “addiction” was, what types of strains they were consuming, how they were consuming them, nor how often they were consuming them.

“CUD” is very open according to ICD-10. It might mean once a day before bed.

Given the lack of information on how cannabis is administered, our question is entirely valid. Does CUD or the Effects of Smoking Cause Perioperative Complications?

CUD or effects of smoking? #2 More information

Even the authors of the study say more research is needed. And indeed, a comprehensive study incorporating data from a controlled source would go a long way. This would include additional control groups, including cannabis users who do not smoke.

#1 Narrative Bias

Is it reasonable to conclude that cannabis use disorder is associated with a 1.16% increase in perioperative morbidity and mortality after major, elective, inpatient, and noncardiac procedures?

Based on the narrative presented in the study, yes. However, turning off CUD for “Effects of Cannabis Smoking” gives you the same results. Maybe a less biased one.

Smoking tobacco significantly increases the risk of complications after surgery. Nobody disputes that. And although cannabis contains many of the harsh chemicals that store brand cigarettes contain, you’re still inhaling burnt plant matter at the end of the day.

The study authors did not go into the specific details of cannabis administration or dosing. They simply identified patients using the ICD-10 codes and made some generalizations.

This study cannot definitively conclude whether the 1.16% increase in perioperative complications is due to cannabis or cannabis smoke.

CUD or the effects of smoking? Without a more thorough analysis, no one can say for sure.