We are excited to share this guest post from Dr. Mohammed Ruzieh from the University of Florida. He dissects a flawed study of stroke prevention in atrial fibrillation
This is a quick way to suspect observational bias. Too many studies today are expedient ways to publish, by taking samples from other work and trying to make them fit the projected outcome with statistical analysis. The really hard work in research is to work with the actual patients so confounding variables are known at the end of the study.
Interesting article. If it's expected that 12 million people will be affected with A-fib by 2030, there has to be reasons for this rising estimate. I don't believe some catch-all as old age is sufficient to explain the expected rise. I suspect it to be more related to environmental factors and lifelong lifestyle choices that have never really been studied.
My problem with cardiology is that it's usually all about drugs and procedures. Most heart problems take years and decades to evolve into serious problems. Therefore, much more study needs to be done into how lifestyle over long periods of time affects the body and heart.
Cutting things out, replacing things, plugging things, stents, and other surgeries done to the heart are purely reactive and not proactive. Changing how the body functions is not a very good idea. Its natural functions should be supported and reinforced.
Thank you for this insightful review, and for sharing it transparently not only with colleagues, but with the public.
It seems this study has parallels with the 2021 report on VSD data, which concluded that there is a non-Covid-19 mortality benefit for Covid-19 vaccinees (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8553028/). An overall mortality reduction for the vaccinated (aRR 0.34-0.54) would suggest a healthy user bias among the vaccinated population, with implications for vaccine efficacy. But this was not their conclusion.
I am not a medical expert. I subscribed to this newsletter because it is easier to understand and gives me ammunition for disagreement with some of my friends.
Thank you, Mohammed. I can think of an alternate explanation. In the treatment group, the patients were under intense frequent oversight by cardiologists and getting lots of reinforcement for adherence and proper attention to health. The control group presumably got considerably less attention. We must always look for every reasonable explanation. Some of the masking studies which showed marginal efficacy never controlled for physical distancing which masking and its institutional environment reinforce. I suspect that physical distancing was more important during late 2020-early 2021 when RSV and influenza were massively decreased in prevalence. This factor would be almost impossible to control and was not considered in publlshed studies.
Thank you for providing this. Small edit for Dr. Ruzieh: parag. 3, first line, 'crevice' not 'crevasse'--although the latter would provide a meme opportunity--mountain climbing, skiing....
Thank you for this insight. As a retired physician, I can tell you that most practicing docs don’t know how to read these nuances in study results( including me). It reminds me about the studies on kidney issues with PPIs. The study headlines used relative risk percentages to make the results seem more impressive. Many of my colleagues, including specialists, jumped on the wagon to switch to H2 blockers. The same tactic was used with the covid vaccines, I believe, to overstate their protective benefits to the lay public through media repetition. If I’m wrong on that analysis, I welcome your input on that subject!
Left atrial appendage occlusion devices GET A HIGHER class of recommendation form AHA . Is theis merited in your view?
This is a quick way to suspect observational bias. Too many studies today are expedient ways to publish, by taking samples from other work and trying to make them fit the projected outcome with statistical analysis. The really hard work in research is to work with the actual patients so confounding variables are known at the end of the study.
Interesting article. If it's expected that 12 million people will be affected with A-fib by 2030, there has to be reasons for this rising estimate. I don't believe some catch-all as old age is sufficient to explain the expected rise. I suspect it to be more related to environmental factors and lifelong lifestyle choices that have never really been studied.
My problem with cardiology is that it's usually all about drugs and procedures. Most heart problems take years and decades to evolve into serious problems. Therefore, much more study needs to be done into how lifestyle over long periods of time affects the body and heart.
Cutting things out, replacing things, plugging things, stents, and other surgeries done to the heart are purely reactive and not proactive. Changing how the body functions is not a very good idea. Its natural functions should be supported and reinforced.
I am suspicious of procedures that remove an organ and claim some benefit. What does the atrial appendage do, besides foment clotting in a few people?
Thank you so much! I love your posts. I am a retired RN with AF and congenital aortic bi-valve. So getting useful information is important to me!!
Nice synopsis and useful caveats on what to look for in studies that are not RCT. thanks.
Thank you for this insightful review, and for sharing it transparently not only with colleagues, but with the public.
It seems this study has parallels with the 2021 report on VSD data, which concluded that there is a non-Covid-19 mortality benefit for Covid-19 vaccinees (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8553028/). An overall mortality reduction for the vaccinated (aRR 0.34-0.54) would suggest a healthy user bias among the vaccinated population, with implications for vaccine efficacy. But this was not their conclusion.
I am not a medical expert. I subscribed to this newsletter because it is easier to understand and gives me ammunition for disagreement with some of my friends.
Thank you so much.
This is beautifully written, thanks you for the analysis made so simple to understand!
I am an internist/epidemiologist and this is a really helpful essay. Thank you.
Would love you guys to do a similar dissection of the [fairly] recent Acetaminophen studies regarding children in utero.
Thank you, Mohammed. I can think of an alternate explanation. In the treatment group, the patients were under intense frequent oversight by cardiologists and getting lots of reinforcement for adherence and proper attention to health. The control group presumably got considerably less attention. We must always look for every reasonable explanation. Some of the masking studies which showed marginal efficacy never controlled for physical distancing which masking and its institutional environment reinforce. I suspect that physical distancing was more important during late 2020-early 2021 when RSV and influenza were massively decreased in prevalence. This factor would be almost impossible to control and was not considered in publlshed studies.
Thank you for providing this. Small edit for Dr. Ruzieh: parag. 3, first line, 'crevice' not 'crevasse'--although the latter would provide a meme opportunity--mountain climbing, skiing....
Thank you for this insight. As a retired physician, I can tell you that most practicing docs don’t know how to read these nuances in study results( including me). It reminds me about the studies on kidney issues with PPIs. The study headlines used relative risk percentages to make the results seem more impressive. Many of my colleagues, including specialists, jumped on the wagon to switch to H2 blockers. The same tactic was used with the covid vaccines, I believe, to overstate their protective benefits to the lay public through media repetition. If I’m wrong on that analysis, I welcome your input on that subject!