So I had a patient recently that had been worked up in the past for high
fibrinogen levels, he was very concerned about it, and my policy is to
go ahead and get a lab if a patient's concerned about it, unless there's some
major reason not to do so. I tend not to follow fibrinogen and this video is a
discussion on why fibrinogen was first discovered to be a risk - Gosh - 30, 40 years
ago. Here's one of the original studies. It was Framingham, you've heard of
Framingham, it's the large study of the - Harvard folks used it. It was a community
longitudinal study. They discovered that fibrinogen and some others as well -
fibrinogen was strongly associated as a risk factor for cardiovascular disease.
The impact of fibrinogen value - this was in '87 by the way in JAMA, so it was a - it
was a big deal at the time. The impact considered as a separate variable was
this comparable - oh, it was comparable to major risk factors such as blood
pressure, hematocrit, being overweight, cigarette smoking; again, it was seen as a
big deal. Now, you started to get a lot of information from groups like LEI.
Here, this is an LEI article which basically describes a lot more about
fibrinogen - how it kills agents that lower fibrinogen, etc. That was, again,
still at least ten years ago. Now, let's get a little bit closer to present-day
and you'll see there was an update in the American Journal of Epidemiology.
That's an excellent journal. This was 1992. So now, we're going from 40 years to
about 30 years (20 - 30 years) and they did surveillance on about 1300 people.
They did find fibrinogen as a risk. It was very much associated, and here's
one of the reasons why. Fibrinogen has fallen out of favor. It's very much
associated with the other risk factors, such as cigarette smoke especially, but
also high blood pressure, diabetes, obesity, etc. So, yes, you heard me mention
those in the originals and, yes, same thing here. Fibrinogen is associated with
being obese, smoking, blood pressure, all of the other or most of the other
standard risk factors for cardiovascular disease. So you begin to get the picture
that maybe the things that I do to manage all of those is also going to
manage fibrinogen. Well, actually, one of the things that this article says is
they thought it was - it appeared to be (from statistical analysis) an
independent risk factor, which means that you take that - so, however, there is an
independent contribution of fibrinogen to cardiovascular disease in general
hypertensive diabetics and cigarette smokers. About half the cardiovascular
risk of cigarette smoking appears to be due to higher fibrinogen levels. So, again,
these fibrinogen is tied up with the other risk factors. There is some
independence, but the question is - how does - how is that independence impacted
when you manage those other risk factors? and I think that's one of the major
conundrums that we have with fibrinogen. Now, again, for those of you who are big
LEI (Life Extension Institute) fans, an article - gosh, again, another - again, about
ten years ago, '08, '06, '08 era - mentioned the top ten tests that LEI
would do for cardiovascular risk screening. Item number two was fibrinogen.
So, again, they - those guys felt it was very important to look at it.
Now, let's get a little bit closer to today. This article actually is a very
interesting article to me and, for our purposes, because one of the things that
that I do look at a lot, is plaque, CIMT. We've got several series on plaque.
Now, these guys actually decided to take a look at association between plasma
fibrinogen and non calcified plaque, which is, again, hot or unstable plaque,
and mixed coronary atherosclerotic plaque. So they did go on - now, this is in an
interesting journal - it's the biology of sex differences. So they did find a
difference in gender on this specific area.
This was 2018, so, again, fast-forwarding to present time regarding fibrinogen and
fibrinogen's continuing link up with all of the other indicators and risk factors
for heart attack and stroke. What was their methods that - ? they took - we'll go to
the next slide. That'll help us show a little bit more about that.
They took 329 subjects and they looked at plaque. They also looked at fibrinogen
levels, what's called enzyme linked immunosorbent assay, (that's
a another long term) people just call it by "ELISA" - it's a lab test where you
basically find an antibody, label it, and then use that antibody to find what
you're looking for. In this case fibrinogen. Again, that parts more of the
geeky stuff for those who are interested. The reality is - and the basic message is
this: For patients that had plaque - this NCP plaque (that's non calcium plaque)
They've mentioned that before here - Non calcified -
the NCP plaque and the mixed plaque had significantly higher fibrinogen so if
you had plaque, whether non calcified or mixed, you still had higher fibrinogen.
Again, that same old song about fibrinogen being mixed up with other
indicators and other risk factors. Well, what was interesting in this one was -
they found that significant relationship in females but not in males. Now, what's
the answer to that riddle? or the question that brings up? I don't think we
know yet. But, again, bottom line is: there is that association. Now, pardon me, this
is another one of those issues - we're having a little bit of trouble trying to
get the visuals to work. I'm - I can see these. Although I have to go up close to
my screen to do it - and I'll read those off to you; the bottom line is - So what?
What - what do you do with fibrinogen when you find elevated levels? This is another
reason why you don't see a lot of discussion about fibrinogen among the
standard medical practitioners, cardiologists, folks like that. Bottom line,
there aren't FDS-approved drugs that
work for this and the things that you do for it are the things that you would do
for the other indicators and the other risk factors - platelet aggregation
inhibitors, such as aspirin, green tea, ginkgo, vitamin E, vitamin A, as well; fish
and olive oil; As a side point, elevated homocysteine levels do tend to decrease
the breakdown of fibrinogen and, again, another relation of fibrin - fibrinogen to
another, may be soft indicator of risk, and then, finally, for those of you who
are interested in supplements and the impact, there's a significant amount of
question and debate around - around giving vitamin C. So, the antioxidants: vitamins A,
C, and E, aspirin, green tea, ginko, and, of course, the major risk
factors, again, you can't out supplement a bad lifestyle. If you're smoking, game
over. So stop smoking. That decreases
fibrinogen. Obesity - avoiding obesity, again, obesity a major risk factor and
then lowering LDL. That one's not quite as quite as strong and quite as
well-documented; and here's a weird one - just to hit - Red herring, totally out of
the cold, (pardon me, pardon the pun) but it's avoiding
exposure to cold; Now, there's a lot of information which would indicate that
maybe some of the - there's some other biomarkers that might be healthy from
brief exposures to cold. I'm not going to get go down that bunny trail today. If
you've made it this far, I appreciate your interest and if you're interested
in some of the bunny trails, some of the questions that come up from this, please
let us know in the - in the comments below.