Welcome to Dr. Warrick's podcast channel. Warrick is a practicing cardiologist and author with a passion for improving care by helping patients understand their heart health through education. Warrick believes educated patients get the best health care. Discover and understand the latest approaches and technology in heart care and how this might apply to you or someone you love. Hi, my name is Dr. Warrick Bishop and welcome to my podcast station and to the Healthy Heart Network. Today I'd like to talk a little bit about D and fish oil and really where they sit because there was a recent trial that came out looking at vitamin D and fish oil. The trial was called the vital rhythm study and quite reasonably the researchers were asking the question should people be taking omega-3 oils and vitamin d supplements to reduce the incidence of atrial fibrillation now we know that omega-3 oils and to a lesser degree vitamin d have been implicated in sort of benefits for the heart so this trial that took about 25,000 people, so a good-sized trial, really wanted to answer that question. They followed these people over about a five-year period, actually. So a really quite a robust sort of study. And during that time, out of those 25,000 people, there were about 900 cases of atrial fibrillation that allowed the statistical data that they could, or the data that they could get some statistical information from. Now, the randomizations were to a vitamin D supplement of about 2,000 international units a day, and that's a pretty standard sort of dose. The other randomization was to omega-3 oils, which was an equivalent of just about one gram a day broken down into EPA and DHA, the two components of marine triglyceride. pharmaceutical grade epa and dha so they were pretty good quality stuff and better than you would get from your local vitamin store supermarket or chemist so what did this study show well in in essence they looked at the rate of atrial fibrillation in the omega-3 group and that came out at 3.74% rate of atrial fibrillation over that time period, over that study period. And they also compared that to the placebo arm. Now, the placebo arm had a rate of 3.43% over that period of time. Now, you've already figured out that the rate of event was higher in the omega-3 group. Well, what does that mean? It was a small relative risk increase. And to be honest, based on the statistics that we use for proving statistical significance, which is the term that we say that means it's better than a 95% chance of it occurring by fluke, by accident, then it didn't fulfill statistical significance. But interestingly, there've been a number of other trials as well that raise the possibility that omega-3 oils may increase the risk of atrial fibrillation. Well, I'm not sure we know the full story on that yet, and I'll come back to it in just a second. The second arm of the randomization was in regard to vitamin D supplementation, and really at the end of that five-year period there was no difference in the rates of atrial fibrillation. fibrillation at all so where does that leave us does that tell us that we shouldn't bother with vitamin d supplementation because it doesn't make a difference or does it tell us that we shouldn't bother about fish oil supplementation well i think it's more complicated than that and the important part of what i wanted to discuss today was that taking these small bits of information from studies which are very specific can I guess question the bigger picture that we're often trying to deal with. So for omega-3 oils, we do know that they will lower triglycerides. And this is particularly so in people who are insulin resistant. So the pre-diabetic population who may have insulin resistance are going to likely benefit from omega-3 oil supplementation for lowering triglycerides. And that same group will get some reduction of blood pressure. And as a consequence of all these good things happening, we do know that in the right population, we can see a reduction of cardiovascular disease. So this vital rhythm trial tells us that the fish oils don't necessarily help us for atrial fibrillation, but they don't give us a clear answer on the bigger picture of omega-3 oils in an individual and their overall health and well-being. Because remember, we know from the GC-P study or the GC-Provencioni study, the GC-Prevention trial from many years ago, that the group given omega-3 oils had a significant reduction in sudden cardiac death. And this was attributed to a reduction in the rate of malignant or nasty rhythm disturbance that occurred in the bottom part of the heart, the ventricle. And so the GCP data and some of the observational data in populations would point to reduced rhythm disturbance in people with omega-3 oils. So how do we reconcile that? Still very difficult to figure out. We know that omega-3 oils are probably also beneficial for brain development, particularly for children. They may be important for maintenance of brain function in elderly. And we also know that they can help with joints and inflammation if taken in reasonable enough doses. So from my perspective... I take a little bit of fish oil and I think this vital rhythm study tells me that if I'm taking it just for the purpose of avoiding atrial fibrillation, I may not get a lot of joy from that. But if I'm taking it with a more holistic view, then there may still be some upside to it. Personally, I think it leaves me with better skin and better joints. The other issue is that of vitamin D and where that fits in. So we know, of course, that vitamin D is important for your bones and calcium metabolism. Lack of vitamin D is a condition called rickets. We know that vitamin D is important for the immune system and therefore inflammation. So people who are further from the equator run a greater risk of developing multiple sclerosis, an immune and inflammatory condition. Vitamin D can have a role in the cholesterol profile and alter risk of heart attack. In certain studies, this has been shown to be associative or suggestive. And importantly, vitamin D, particularly in locations where there are dark, cold winters where people don't get the sun, is implicated in what we call seasonal affective disorder, where people's mood may be down. during those winter months. So, what's the take-home? Does vital rhythm tell us that fish oil and vitamin D are just not useful supplements? Well, I don't think it tells us that per se. I think it tells us... that in the doses given in a broad population without a closer look at some of the defining differences between those populations, it doesn't seem to make a great deal of difference for atrial fibrillation alone, and a very small question mark as to whether that fish oil increases the risk of atrial fibrillation in the population studied. If we step back from it, I think there's a lot of good reasons to want to make sure that we're eating good fatty fish, and if you don't eat a lot of fatty fish, you might supplement. I take a few... grams of fish oil daily and similarly you want to make sure you're out in the sun when you can if you're like me and you live in a place where winters are long and dark then you may well wish to supplement with vitamin d when you can't get out in the sun and get good sun exposure just as a by the way the recommendation for sun exposure is about 10 odd minutes about three times a week but you need to do that to a reasonable part of your body you can't just have a small part of the back of your hand exposed to the sun you probably need your back exposed or your abdomen or legs so that you get a decent if you like dose of sun to the skin well that just about sums it up for me and the vitamin d fish oil study that I wanted to share. I hope you've learned a little bit from this and found it engaging and entertaining. If you have any queries or questions, please drop us a line at members at drWarrickbishop.online. If you've got any suggestions for future podcasts, of course, please let us know as well. For now, I'm going to wish you the very best. Thank you for joining me. Please come back again and have a listen and get some more information. Until next time, I wish you the very best. Take care and please don't die from a heart attack. Goodbye. You have been listening to another podcast from Dr. Warrick. Visit his website at drWarrickbishop.com for the latest news on heart disease. If you love this podcast, feel free to leave us a review.
