In the previous article, I introduced the association between H pylori and cardiovascular disease.
If you haven’t yet read that post, it will really help you, so I humbly request that you please read it first by clicking here.
Now, having read the previous post, you’ll be familiar with the basic associations between H pylori and cardiovascular disease.
H pylori symptoms don’t just include heartburn, acid reflux, belching, bloating, stomach pain and ulcers.
In later posts, we’ll cover how certain H pylori strains influence a host of processes and chemicals in your body that promote cardiovascular disease.
These factors include chronic inflammation, cholesterol, blood pressure, insulin resistance, C-reactive protein, homocysteine and others.
Ultimately, these cardiovascular effects can develop into heart disease – angina, heart attacks and even strokes.
In this post, I want to show you specific research connecting H pylori with the incidence of heart disease.
We’ll cover other cardiovascular diseases like high blood pressure, insulin resistance and high cholesterol later.
This post is about full-blown heart disease.
To do this, I want to introduce an important concept about different H pylori strains.
Before we go any further, I’d like to point out that simply having a plain old H pylori infection might not increase you heart disease risk one iota.
To investigate H pylori and cardiovascular/heart disease properly, we have to split H pylori down into different sub-types or strains.
Some H pylori strains have what we call “virulence factors”.
Keeping it simple, these virulence factors make H pylori more angry or aggressive.
These virulence factors increase the level of threat to your health, or H pylori’s ability to trigger symptoms and disease.
Why is this important?
Well, it’s becoming more widely accepted that H pylori might actually be a normal constituent of our gut microbe population.
In fact, H pylori might even be protective in some instances in ways we don’t yet fully understand.
H pylori appears to protect against certain symptoms and diseases, including asthma, allergies and oesophageal cancer.
Putting it bluntly, you can’t tarnish all H pylori strains with the same brush – some cause more problems than others.
When it comes to heart disease and other H pylori complications such as ulcers, it appears that certain H pylori strains are more influential than others.
Two H pylori strains in particular seem problematic
These are CagA and VacA.
(long names: cytotoxin-associated gene A (CagA) and vacuolating cytotoxin A (VacA)
H pylori has the ability to inject or secrete these toxins.
The net result? More symptoms and more disease.
So when I’m talking about H pylori and cardiovascular disease, it’s the CagA and VacA strains that are of utmost importance.
For all we know, other H pylori strains might not have any bearing whatsoever on cardiovascular disease.
Put plainly, the scientific literature shows it’s the CagA and VacA H pylori strains that are most closely associated with cardiovascular diseases.
Unfortunately, general medical H pylori testing doesn’t generally tell you whether you have CagA or VacA strains.
In my opinion, this is a problem.
If you want to get tested for CagA or VacA H pylori, you’ll need to run a test through a private lab.
Two labs I know of – DRG and Diagnostic Solutions Laboratory do this testing.
It’s a single stool sample that is assessed for the DNA of H pylori in general, as well as CagA H pylori and VacA H pylori.
You simply do the test at home and send it to the lab.
If you want to do one of these specific H pylori stool tests, you can check out details here.
The European Helicobacter Study Group has been writing about H pylori and cardiovascular disease for some time.
The study group has its very own medical journal, called Helicobacter, which is published monthly.
I do my best to read every edition, which is how I get to know the inside scoop on so many issues that doctors are often unaware of.
Along with other medical journals, they’ve published loads of information on H pylori and cardiovascular disease.
Their info is very much worth checking out if you want more detail on anything that’s H pylori-related, but it’s quite “sciency” and not always easy to read.
In 2007, a group of researchers from Rome studied 40 people who had been diagnosed with ischemic heart disease.
Ischemic simply means arteries around the heart have been narrowed, reducing blood flow and oxygen delivery.
The patients did a coronary angiography, were assessed for classical heart disease risk factors and for CagA H pylori antibodies.
The researchers found statistically significant correlations between anti-CagA antibodies and the severity of arterial narrowing, or plaque build-up.
Furthermore, by looking at the CagA antibody levels, they were able to predict how severe the patients’ heart disease would be.
Here is what they said:
“The results support the association between CagA-positive H pylori infection and coronary atherosclerotic burden. Further studies are now needed to elucidate the mechanism behind this association.” 1
Next, a 2010 study conducted in China looked at how CagA H pylori strains might be involved in coronary heart disease.
Researchers estimated the severity of heart disease in each patient and H pylori status was assessed using a breath test.
IgG antibodies against CagA H pylori were analyzed to determine whether the CagA strain was present.
The researchers then divided the study subjects into three groups:
The severity of artery narrowing was higher in people who had H pylori CagA.
In this study, total cholesterol, “bad” LDL cholesterol, apolipoprotein B, C-reactive protein and oxidized LDL were also higher in the CagA-positive subjects.
These are all cardiovascular disease risk factors.
The researchers concluded:
“More serious coronary atherosclerosis was observed in CHD patients with H pylori-positive, CagA-positive infection. (This type of) infection might be involved in coronary atherosclerosis by modifying serum lipids, enhancing LDL oxidation, and activating the inflammatory responses.” 2
Another study looked at 20 patients with coronary artery disease and 20 patients with normal coronary arteries.
Either the severity of artery hardening or the extent of plaque build-up was evaluated in the heart disease patients.
H pylori CagA patients had more extensive coronary artery disease compared with CagA-negative patients.
Here is the study’s conclusion:
“These results support the association between CagA-positive H pylori infection and coronary atherosclerotic burden. Further studies are needed to better elucidate the mechanism by which CagA strains of Helicobacter pylori may promote atherosclerosis.” 3
In a 2008 Chinese study, subjects were examined for aorta thickening (the main artery leaving the heart).
They were also tested for H pylori and the CagA strain.
Patients who had CagA H pylori infections had a 63% incidence of aortic atheroma (plaque).
Patients who had H pylori infections but not CagA had a 46.7% incidence of aortic atheroma.
Patients without H pylori infections had a 29% incidence of aortic atheroma.
The researchers concluded that once other risk factors such as smoking had been taken into account, CagA H pylori infection was independently associated with aortic atherosclerosis (plaque).
Their conclusion was:
“This study suggests a gradient of atherosclerosis between uninfected individuals and patients with CagA-positive H pylori infection and should prompt research into the role of CagA-positive H pylori infections in the inflammatory atherosclerotic process.” 4
From these studies, the trend seems to be that CagA H pylori strains have an ability to contribute to heart disease.
Let’s not “cherry pick” the data
Being honest, data from four studies are not really robust enough to draw convincing conclusions.
For all you know, there could be, say 100 studies and 96 of them may show no association between H pylori and cardiovascular disease.
If I chose to show you the four studies showing an association, whilst ignoring the other 96, you would be misled.
This concept is called “cherry- picking” in the medical and scientific world and it happens a lot.
How to avoid cherry picking
To avoid the cherry-picking issue, let’s look at papers where scientists collated data from multiple studies and examined them for trends between H pylori and cardiovascular disease.
These studies are called “meta-analyses”.
Here, researchers take data from lots of studies, pool the data and run complex statistical analyses to find trends and associations.
Meta analyses usually provide stronger and more robust evidence than individual studies.
In 2008, Zhang and colleagues examined 26 different case-controlled studies.
The data showed that CagA H pylori strains appear to increase the risk of strokes and heart disease.
The main conclusions were:
“Our results support the hypothesis that CagA strain infection is significantly associated with susceptibility to strokes and coronary heart disease.” 5
In other words, data from 26 separate studies confirmed an association between CagA H pylori and cardiovascular disease.
A further meta-analysis examined data from 17 separate studies and drew similar conclusions.
In 10 of the studies, data revealed an association between CagA H pylori and heart disease.
There was no association between heart disease and non-CagA H pylori infection.
In 3 more of the studies, the association between CagA H pylori infection and heart disease was weaker, but still present.
In 4 studies, CagA H pylori was significantly associated with a narrowing of blood vessels / lack of blood supply in and to the brain (with the potential to cause strokes).
Again there was no association for non-CagA negative strains .
The researchers stated:
“We found a small but significant association between vascular diseases and virulent CagA positive strains of H pylori. The lack of association with CagA negative strains further supports the hypothesis of an independent relationship between virulent strains of H pylori and vascular diseases.” 6
By the way, the information I’m presenting here is available to the general public at the PubMed website.
Isn’t it interesting that despite being publicly available, the info is not reported by the mainstream media?
Nor do we hear many doctors talking about it.
I find this interesting because heart disease kills more people than any other condition.
Surely people have a right to know what’s going on?
Pooled data from meta-analyses indicates that H pylori infection is associated with cardiovascular disease.
“Association” does not prove cause and effect.
We can’t say “you have Cag-A H. pylori, so you’re going to get heart disease”.
It doesn’t work that way.
What the data actually suggest is that folk infected with the Cag-A H. pylori strain are:
If CagA H pylori strains are associated with increased incidence and severity of cardiovascular diseases, we might also expect to see the occurrence of “acute events”.
These include angina attacks, strokes and heart attacks.
Furthermore we might see changes in some of the metabolic markers associated with heart disease risk such as cholesterol levels and blood pressure.
The next few posts in this series explore these possibilities, starting with H pylori and its effect on blood pressure.
The blog series is split into several easy-to-read posts.
Each post is a snapshot of a chapter from my e-book, H pylori: From Heartburn to Heart Attacks.
In each post I’ve provided links to the other articles in the series.
I recommend you read them in sequence given below.
I also recommend you get the book, not because I’m a salesman but because I want you to have the information at your fingertips, for a lifetime.
The book contains info that is not included in the blog posts on how to use diet, lifestyle and supplement modifications to minimize your heart disease risk.
Next, I recommend you read the posts in this sequence (if you can’t link through to the articles, it just means they have not been published yet, and are coming very soon.)
1 H pylori and high blood pressure (hypertension)
2 H pylori and insulin resistance, diabetes and cholesterol (metabolic syndrome)
3 H pylori and inflammation
4 H pylori and oxidative stress
5 H pylori, vitamin B12, folic acid and homocysteine
It’s over to you – do you have any comments, questions or stories relating to H pylori, digestive health or even cardiovascular disease?
If so, we’d love to hear from you and you’re very welcome to join the discussion by leaving a comment, below.