INR drops with excercise

[ajc1991]

Hello, I'm a 24 year old male and I'm one of those whose INR drops when I excercise. I am currently running 3 miles 5 times a week. I'm taking ten MGs of Coumadin every day except for Wednesday, I then take 12 MGs. I've been in range with this dosage.

I had read among some other posts, and people seem to think that your INR drops with exercise because since your heart rate revs up with exercise, the Coumadin is then metabolized quicker and not fully absorbed by your body. If that is true, here is my question:

I know Coumadin takes about 24 hours for your body to fully absorb it and for it to affect your INR, which is why I try to exercise around 4 PM so the Coumadin that I took the evening before has had nearly 24 hours to work its magic since I take my Coumadin at 5 PM every day. If I was to exercise in the morning, say around 9 or 10, would that mean that the Coumadin would not hit my body because it hasn't had long enough for it to be fully absorbed? Would it be metabolized too quickly with exercise and not have the time it needs to fully work?

 

[pellicle]

Hi

...work its magic since I take my Coumadin at 5 PM every day. If I was to exercise in the morning, say around 9 or 10, would that mean that the Coumadin would not hit my body because it hasn't had long enough for it to be fully absorbed? Would it be metabolized too quickly with exercise and not have the time it needs to fully work?

think of it as a pipeline proces, you need to prime the pipeline with warfarin to then effect the metabolism of Vit K and in turn effect the metabolism of coagulation which drops the INR.

The increase in metabolism (as I've seen it in me) does not hit in so fast as to make morning dose / evening measurement an issue. If you are doing a one hit of high exersize (like greater than 2000KCal) that may make a dent in your INR after 24 or maybe 48 hours, but it will recover again in a few more days.

If you know you'll be training hard (like greater than 1000KCal per day) for days on end (or every second day with a recovery) then you may need to put a small margin more on your daily dose. Something like the 2 mg you've mentioned ... perhaps a little less (assuming you do it daily not alternating doses daily)

does that make sense?

 

[camgough]

This is interesting. I'm having more and more energy to exercise now and have also done a few 5km runs.

I understand everyone metabolizes warfarin differently, but is 10mg and 12mg alot? I'm not sure how big you are, or if that makes a difference, but I'm a 34 yr old male, 6 foot, 186lbs and I am taking 6mg daily.

I'm glad to see you are doing well ajc, you were an inspiration to me pre-op because of your quick recovery!

 

[pellicle]

Hi Cam

glad to hear you have more energy....

I understand everyone metabolizes warfarin differently, but is 10mg and 12mg alot? I'm not sure how big you are, or if that makes a difference, but I'm a 34 yr old male, 6 foot, 186lbs and I am taking 6mg daily.

the main issues in warfarin metabolism is not dose / kg body weight as it is with many drugs, its related to genetics of the variants in a metabolism in the liver know as P450

http://journals.plos.org/plosgenetic...n-1000433-g001 A Genome-Wide Association Study Confirms VKORC1, CYP2C9, andCYP4F2 as Principal Genetic Determinants of Warfarin Dose



you'll find here people who have doses that range from 4mg / day through to over 60mg per day to keep their INR around 2.5

Read this thread ... http://www.valvereplacement.org/foru...se-of-warfarin

There are some excellent points in there, and some shocking factoids about how warfarin was historically administered. We have come a long way but many still hold fears from the past bad practices.

viva la difference

 

[ajc1991]

think of it as a pipeline proces, you need to prime the pipeline with warfarin to then effect the metabolism of Vit K and in turn effect the metabolism of coagulation which drops the INR.

The increase in metabolism (as I've seen it in me) does not hit in so fast as to make morning dose / evening measurement an issue. If you are doing a one hit of high exersize (like greater than 2000KCal) that may make a dent in your INR after 24 or maybe 48 hours, but it will recover again in a few more days.

If you know you'll be training hard (like greater than 1000KCal per day) for days on end (or every second day with a recovery) then you may need to put a small margin more on your daily dose. Something like the 2 mg you've mentioned ... perhaps a little less (assuming you do it daily not alternating doses daily)

does that make sense?

I didn't really understand it unfortunately

 

[ajc1991]

This is interesting. I'm having more and more energy to exercise now and have also done a few 5km runs.

I understand everyone metabolizes warfarin differently, but is 10mg and 12mg alot? I'm not sure how big you are, or if that makes a difference, but I'm a 34 yr old male, 6 foot, 186lbs and I am taking 6mg daily.

I'm glad to see you are doing well ajc, you were an inspiration to me pre-op because of your quick recovery!

I'm so glad you're doing well and everything went as planned! 10 mg is considered a bit of a high dose but there's people out there who have gone higher. It might have to do with my metabolism since I'm 24. Everyone is different so that factors in as well. I'm 5'8 and 158 pounds.

 

[pellicle]

I didn't really understand it unfortunately

OK, so before I type a shed load, what don't you understand and what would you like to understand that I didn't cover?

 

[ajc1991]

OK, so before I type a shed load, what don't you understand and what would you like to understand that I didn't cover?

Ok, so what you're saying is it doesn't matter at what time I exercise, but at how hard I'm exercising?

 

[pellicle]

Ok, so what you're saying is it doesn't matter at what time I exercise, but at how hard I'm exercising?

pretty much .. and its only when you have consistent exersize levels you need to worry about

 

[ajc1991]

pretty much .. and its only when you have consistent exersize levels you need to worry about

Thank you very much Pellicle

 

[cewilk]

This also may be why I am having a hard time staying in range. I am supposed to stay in 2.5-3.0. My most recent INRs were 1.8 and 1.6 respectively. I too have been increasing my cardiovascular exercise and just recently began lifting weights again. I don't know what else could be lowering my INR since my diet has remained pretty much unchanged since surgery.

 

[pellicle]

Hi

This also may be why I am having a hard time staying in range.

could be, although to me you are not far out of surgery, it could just be your body changing as it heals. I know my INR changes when I get sick

I am supposed to stay in 2.5-3.0.

personally I reckon that's a tight rope to walk. I personally don't even think its possible. I reckon that the idea that the Europeans use of:
*target INR = *value (say pick 2.5)
*accept lattitude and attempt to minimiise it

is the best method. Its similar to what manufactures use in quality targets.

For myself I find that I vary around 2.6 by about 0.3 either side most of the time. I found an interesting quote in the analysis of the German Experience with Low Intensity Anticoagulation study:

As > 90% of INR measurements during the entire follow-up period were within the therapeutic range of INR 2.0 to 4.5, which is the lowest erratic INR ever published

my thoughts on that was "wow, if thats the lowest variation ever in a followup no wonder people have problems" My own experience is much much tighter than that, but over a year nowhere near as tight as your goals.

My most recent INRs were 1.8 and 1.6 respectively. I too have been increasing my cardiovascular exercise and just recently began lifting weights again. I don't know what else could be lowering my INR since my diet has remained pretty much unchanged since surgery.

if I was your INR manager (or telling them what to do, I'd steer that up a bit. None the less I personally would not be so worried on the 1.8 side for a short visit because I see evidence accumulating that with all the modern bileaflet pyrolytic carbon valves such INR is not associated with significant risk. For instance

The LOWERING-IT study was a prospective, open-label, singlecentre
randomized controlled trial that compared the thromboembolic
and bleeding events between two different anticoagulation intensity
levels in low-risk patients undergoing a single aortic mechanical
replacement. The two anticoagulation intensity levels were the low
anticoagulation intensity, with a range INR of 1.5 to 2.5 (LOW-INR
group), and the currently recommended intensity, with the standard
range INR of 2.0 to 3.0 (CONVENTIONAL-INR group).

 

[tom in MO]

My range is 2.0 to 2.5, I home test and have no trouble staying in range. Right now I have been in range for 4 months, and for the past year I have been no lower than 1.9 and no higher than 2.8. I "dose the diet" and love greens : )

 

[gerrychuck]

Exercise has a profound effect on my INR, but only if it is moderate intensity or higher. For me the key is to keep my exercise routine as consistent as possible to aid in maintaining my INR within range and avoid adjusting my dosage. It's been working very well lately; haven't had to adjust dosage at all since February.

 

[realkarl]

I know theory says exercise activity level does not influence the INR levels as a function of Warfarin dosage. Be that as it may, but when I started ramping up my exercise levels significantly, to bicycling an hour or more every day, I had to increase my Warfarin dosage quite a bit. Then it stabilized and even went the other way, but not as far back as it was before the exercise change.

After the FDA approved On-X's reduced INR range for low-risk aortic valve patients, I was allowed by my INR clinic to reduce my range to 1.5-2.5. It took a little effort, and I had to involve On-X and possibly my surgeon (I don't know what went on behind the scenes) to be approved, since the clinic initially refused to change their practices. I usually stay around 2, but don't worry if it drops a little below.

 

[yotphix]

I'm so glad you're doing well and everything went as planned! 10 mg is considered a bit of a high dose but there's people out there who have gone higher. It might have to do with my metabolism since I'm 24. Everyone is different so that factors in as well. I'm 5'8 and 158 pounds.

I also take a very high dose. I take 11mg every day. I'm 46 though, so maybe age isn't key! When my dose slowly crept up from the 5mg they started me on, to the 11mg I take each day now, I thought it was because I exercise so much. Then, work got busy, and I stopped finding the time to run. (I was doing 3 miles 4-5 times/week). It made no difference at all. I still take the same dose, and I'm still in range. I also thought it might be my high vitamin K diet, with lots of leafy greens, but then I started to eat at work quite a bit, and again, it made no difference. I'm now more or less convinced that we are all basically individuals, and some of us are stable, while others are not. Some of us need 10+ mg daily, and others need just 1mg daily. Figuring out who you are and what you need is the hard part.

 

[Thomas]

I've been running a small experiment on myself to see how my body reacts to exercise and found this older thread.

I lift weights 3-4 times per week
My Warfarin dose is 10mg and I've been in range (reading around 3.0, Range 2.5-3.5) for a long time now without issue.

A few weeks ago I travelled for a week and did not work out. Diet was normal and minimal drinking. Same climate (if that matters).
When I tested after the trip, my INR jumped about .7 of a point. This surprised me as it's a pretty big jump and is the reason for looking at how exercise affects my INR. It was the only change I could think of.
Got back, worked out for the next week as normal; INR dropped by .5 at next reading.
Last week I was too busy to work out and tested .4 up.
This week, I've worked out twice so far and tested; INR dropped .5

I can't think of anything else that's been changing in my routine other than exercise regimen.
Seems a bit overly sensitive with the swings but management works fine so no issues.
Just interesting to see my body react the way it does. I imagine everyone is different.

 

[tom in MO]

Two data points that correlate with your theory is nice but not significant nor proof of causation. I find that when I travel, my INR changes and I don't work out.

 

[Thomas]

Have you tried to figure out why your INR drops when travelling? It's interesting. Could be diet, sleep patterns, who knows. As long as you are aware of it, it's to your benefit.

Agreed, 2 points are not proof; disagree with your assessment of it not being significant (at least from a personal standpoint). I'm far from being a scientist but I am to quote Seinfeld, "Master of my Domain" all be it a different area of domain.
When I compete in a couple of triathlons this summer I'll be watching my level pretty closely to see what happens. I suspect I'll be in for a dip post race maybe a day or two later.
If nothing else I have an idea going into the races of what might cause INR fluctuation in my body afterwards.

 

[pellicle]

Have you tried to figure out why your INR drops when travelling?

I can't speak for Tom, but myself no. After over seven years of detailed collection of data points and examining theories and applying that to the data (including regression analysis among other techniques) I can find no theory (which is simple) to explain what I see in my own variance.

I no longer care because through out all that I've done the one thing which works: measure my INR weekly and adjust dose as required by the intention to be between 2 and 3.

Simple really. My full notes for INR guidance here:
Managing my INR (some practical tips observations and theories)