#4 Wart is the best treatment for warts?

This episode delves into the highest quality trial ever done on the treatment for warts. This randomised controlled trial published in the CMAJ compared cryotherapy with liquid nitrogen to salicylic acid wart creams to doing nothing.

250 patients were recruited in primary care and follows up for 13 weeks, The primary outcome was complete resolution of the wart by that time.

The bottom line was that for plantar warts there was no difference between cryotherapy, salicylic acid cream or doing nothing in terms of cure rates or patient satisfaction at 13 weeks. For other warts, there is a 35% absolute increase in cure with using cryotherapy over salicylic acid and a 46% absolute increase in patient satisfaction. The prognosis is worse for warts that have been there for longer than 6 months, and for plantar warts, the prognosis is worse if the patient is 12 years old or older.

In this episode we also discuss the importance of allocation concealment.

Reference: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2952009/

music by Polyrhythmics, song El Fuego

#3 Does CPAP Reduce CVD in Sleep Apnoea? – SAVE trial

In this episode we delve into the SAVE study which was THE landmark trial that investigated whether using CPAP (Continuous Positive Airway Pressure)  to treat Obstructive Sleep Apnoea (OSA) also improved cardiovascular disease. The trial also assessed the impact of CPAP on quality of life.

The study randomised 2,687 patients to either receive CPAP or not. These patients were at very high risk of cardiovascular disease, having a previous history of stroke or myocardial infarction. They all underwent an overnight sleep study in a core sleep laboratory and all had to have moderate to severe sleep apnoea. Those who were dangerously sleepy, with an Epworth Sleepiness Scale of greater than 15, were excluded.

After and average of 3.7 years they found no difference in cardiovascular disease between those getting CPAP versus those who did not. 15.4% of those not getting CPAP developed cardiovascular disease versus 17% of those who did get CPAP. This was not statistically significant but it was favouring those who did not get CPAP.

There was an improvement in sleepiness in the CPAP group, with an average reduction of 2.5 points on the 24 point Epworth Sleepiness Scale. There was also a slight reduction in anxiety and depression scores, but the average change was not clinically significant.

So what’s the bottom line?  In patients who have obstructive sleep apnoea, and are not severely sleepy, as defined by an Epworth sleepiness scale score of 15 or less, CPAP will marginally improve sleepiness but have no impact on their cardiovascular disease.

In this episode we also discuss associations versus causations, appropriate participant numbers for cardiovascular trials and Star Wars?…yep….Star Wars!

The trial was published in NEJM in September 2016 and can be found here: http://www.nejm.org/doi/full/10.1056/NEJMoa1606599#t=article

Music by Polyrhythmics, song title El Fuego

#2 SPRINT trial – which blood pressure target is best?

In episode 2 of the Evidence Based Medicine Podcast we delve into the SPRINT trial.
This trial assessed whether targeting systolic blood pressure to less than 120mmHg is better than targeting to less than 140mmHg it terms of harms and reduction in cardiovascular disease.

The trial was conducted in 9,361 patients with very a very high risk of cardiovascular disease but who didn’t have diabetes or a past history of stroke. They were randomised to 2 groups: A standard blood pressure group who were targeted to a systolic BP of less than 140mmHg or an intensive blood pressure group who were targeted to less than 120mmHg systolic. They were followed for an average of 3.3 years

In this episode we go through the results of the trial, it’s impact on hypertension guidelines across the world and how it sits in the face of other similar trials, most notably the ACCORD BP trial. We also discuss some of the controversy about the trial as reported in many commentaries in the literature.

I was a very well done and important trial published in NEJM in November 2015 and stands for “Systolic Blood Pressure Intervention Trial”…I guess SBPRINT trial wouldn’t have sounded as good!

The bottom line is that for patients with hypertension, at high risk of cardiovascular disease, but without diabetes or previous stroke, treating them to a systolic blood pressure target of less than 120, compared to less than 140 will decrease their chance of cardiovascular disease by 1.6% over 3.3 years and will decrease their chance of dying by about 1%. But it comes at a cost, most important of which is an increase in acute renal failure by 1.8%, an increase in worsening renal function by 2.7% and an increase in being seriously harmed by episodes of hypotension, syncope or electrolyte abnormalities by about 3%

Here is a more in depth look at the results:

The benefits of treating blood pressure to 120 versus 140 systolic are as follows:
1. A reduction in cardiovascular disease from 6.8% to 5.2% with an absolute reduction of 1.6% or a Number Needed to Treat (NNT) of 63 over 3.3 years.
2. Death from any cause decreased by 1.2% – It went from 4.5% to 3.3% with a NNT of 83 over 3.3 years
3. Cardiovascular death decreased by 0.6% – It went from 1.4% to 0.8% with a NNT of 167
4. Heart failure decreased by 0.8% – It went from 2.1% vs 2.3% with a NNT 125
5. There was no difference in AMI or stroke

The harms of treating blood pressure to 120 versus 140 systolic are as follows:
1. Worsening renal function increased by 2.7% – it went from 1.1% to 3.8% with a Number Needed to Harm (NNH) of 37
2. – Acute renal failure increased by 1.8% – it went from 2.6% in the 140 systolic group to 4.4% in the 120 systolic group. NNH 56
3. Serious adverse events increased (events that were either fatal or life threatening, or required prolonged hospitalisation, or resulting in significant disability). Episodes of hypotension increased from 2% to 3.4% with a NNH 71
– Syncope increased from 2.4% to 3.5%, with a NNH 91
– Electrolyte abnormality also increased from from 2.8% to 3.8% with a NNH 100
– There was no difference in injurious falls, it was about 2.2% in both groups.

Reference: http://www.nejm.org/doi/full/10.1056/NEJMoa1511939
Music by Polyrhythmics, track titled “El Fuego”

#1 – Introducing EBM podcast

Welcome to the Evidence Based Medicine Podcast

Hello and welcome to the evidence based medicine podcast where every episode we will discuss a landmark clinical trial that has shaped medicine as we know it. My name is Daniel Aronov and I am so excited to launch this podcast.

In this podcast we will discuss the most important clinical trials in medicine. The ones that have shaped our current practice of medicine, the ones that have been the basis of guidelines and the ones we should all probably know about to improve the care of our patients.

I must admit I didn’t really like evidence based medicine during medical school. I found it boring and complicated and echchc. But now I love it and I want to share it with everyone. I want to show you that it’s not boring. I want to show you that it’s actually really important.

Why Evidence Based Medicine Is Important

Firstly its important because unfortunately its the only way to access information in the details that our patients deserve to know. I mean we can look at guidelines, but all they will do is say: “if such and such a clinical scenario, use drug A”.  But they don’t give you details about the magnitude of benefit. The guidelines won’t tell you how likely drug A will help your patient when fall into this clinical scenario.

For example, a guideline may say to use amitryptaline first line for migraine prevention.  But it won’t tell you how likely it is to reduce your patients migraines. To know that you have to look at the evidence. There you’ll find a systematic review that shows that 40% of people had improvement in their migraine symptoms with daily amitryptaline versus 25% of people who took placebo. It was also tell you the harms and how often they are likely to occur. So it can give you better tools to be able to talk to your patients about therapies that you want to initiate.

Another example would be a guideline recommending say, ezetemibe for prevention of cardiovascular disease in those with high cholesterol. But it will never tell you the decrease in cardiovascular disease you can expect from the drug. You’ll only get that by looking at the evidence. In this case it was the IMPROVE-IT trial and there you’ll see that over 7 years of use, in very high risk patients ezetemibe reduced cardiovascular disease by 2%. We should definitely cover this trial in another episode.

And again, this can help you talk to your patients about this drug.

The second reason why evidence based medicine is important is because we’re constantly being barraged by drug company reps. You know, with their free lunches and drug samples and ridiculously good looking features. Well they will come at you with a very biased perspective of what they are trying to sell you, knowing how to use evidence based medicine can put you back in control to see the information in an unbiased way so that you can be better informed about when its right for your patients.

The aim of Evidence Based Medicine Podcast

There is so much medical literature out there it can be impossible to keep up. That’s why this podcast was created, so that you know about the most important studies, about the most important medications and so that you don’t need to rely on drug companies to keep up to date.

This podcast is the product of a really immense passion for evidence based medicine. Musicians might understand the feeling of being so in love with a song that the only way you can release or express that love is by actually playing the song. Listen to it a million times won’t quench that love for the song, only playing it will. So that’s why I’m doing this podcast. To express my love for evidence based medicine and to get more people to appreciate the beauty and the importance of it.

So thanks for listening. Please subscribe wherever you listen to podcasts, feel free to tweet me @ DrAronov or leave a comment right here.

 

Music by Polyrhythmics, track titled “El Fuego”