What To Do If You Have An Early Family History Of Heart Disease
The steps most people should take if they have an early family history of heart disease.
If you have an early family history of heart disease, there are specific steps you need to take to define if you have an increased risk and what to do about it.
Heart disease is the leading cause of death worldwide, and the probability of someone in your family having heart disease is likely to be high.
This does not mean it was genetic.
Just that heart disease is common.
The question most people are trying to answer is whether the heart disease that is in their family has a genetic cause.
And if so:
Can they work out what it is?
And.
What can they do to reduce their risk?
What Defines Early?
There is no clear cut-off here.
Some groups will state that any heart events at less than 55 years of age for males and less than 65 for females define early heart disease.
But there is no hard and fast rule here.
A heart attack in a 56-year-old male is early in anyone's books.
However, the above age cut-offs give a good idea of what we consider the early presentation of heart disease.
The 55- and 65-year-old cut-offs are also the age at which, on average, 50% will go from a zero CT calcium score to a CT calcium score greater than zero.
Therefore, if someone presents with an event earlier than this age, they likely have been building up plaque for a considerable period prior to this.
Here is what I DON’T consider as early heart disease.
“Dad had a heart attack at 78. He had high blood pressure and high cholesterol most of his life, and he wasn’t great at taking his tablets.”
Here is what I DO consider as early heart disease.
“Mum had bypass surgery at 63. She never smoked, and her brother died suddenly from a heart attack at age 50.”
See the difference.
But what about this scenario?
“Dad had a heart attack at 62. He smoked 20 a day since he was a teenager.”
In this scenario, we don’t really know.
A genetic cause could have accelerated the process, but so also could 40 years of smoking.
When smoking is in the mix, it seriously muddies the water.
The same is true of uncontrolled diabetes or high blood pressure.
What I am trying to get across is that it is very common for a parent to have had heart disease, but that does not mean it has a genetic origin.
Inheritance And Expression
It is also worth noting that although a family member may have had early heart disease for genetic reasons, it does not automatically mean that you have inherited that risk.
This is a crucial point that is often overlooked.
Yes, you may be at a higher risk of inheriting a risk variant, but that doesn’t mean you will.
Secondly, just because you HAVE inherited a genetic risk factor, it does not mean you will manifest the disease as early as a parent.
Most genetic risks for heart disease increase risk, but with close attention to other risk factors, overall cardiovascular risk can be reduced.
Even in those with increased genetic risk for heart disease, adherence to good lifestyle factors can reduce risk by about 50%1.
Not All Early Heart Deaths Are Due To Heart Attacks
Lastly, it is always important to be clear about the cause of death in family members with suspected heart disease.
If a parent or an uncle had coronary artery bypass surgery at age 50 and then died suddenly with a heart attack being shown at autopsy, then you can be pretty certain coronary artery disease was the cause.
Most of the time, coronary artery disease will be the cause.
But not always.
When you hear the story, my cousin died suddenly in their sleep at age 26.
That is unlikely to be due to coronary artery disease and more likely to do with a sudden irregular rhythm of the heart.
The workup in this instance is VERY different.
And confusing this as early coronary artery disease can lead you down the wrong path.
What To Look For
Ok. So, you fall into the category of true early heart disease as a result of coronary artery disease.
You are 35 years old.
What do you do next?
The first thing I would advise is to ensure you are getting the lifestyle basics right. (If you don’t know what those are, I suggest you go back to the many prior articles I have written on the topic)
But let’s assume you have these down.
Lipoprotein (a)
Lipoprotein (a) or Lp(a), pronounced “L P Little A”, is the most common genetic cholesterol particle disorder in the population.
It impacts about 10 to 20% of the population2.
You know loads of people who have an elevated Lp(a).
They just don’t know they have.
When I hear, “Dad had a heart attack at 45, and his brother had a heart attack at 50.”
The first thing I think of is Lp(a).
The problem is that Lp(a) is rarely tested for.
Which is bonkers.
The excuse given for not testing it is that there are no specific approved treatments to lower it. (This is very likely to change in the next few years).
Also, just because you cannot reduce Lp(a) does not mean you cannot reduce overall risk.
Lastly, as crazy as this might sound to some physicians, sometimes, just sometimes, patients want to just know if they are at increased risk by being a carrier.
I have written extensively about Lp(a) in previous posts (Here, Here, Here, Here) so I will just mention a few points.
You can have normal LDL cholesterol levels and an elevated Lp(a).
And even in this setting, your risk is increased.
An elevated Lp(a) does increase your risk of early heart disease, but with a more aggressive strategy for overall risk reduction, e.g. lowering ApoB and blood pressure, overall risk can be reduced.
Lastly, accessing Lp(a) testing can be tricky.
Which blows my mind, given how much of the population it impacts.
It is often done only in hospital labs, and only some primary care practices may be able to order this test.
In my view, everyone should have an Lp(a) assessed at least once in their lives, but this is a must-do test if you have an early family history of heart disease.
The next point I also cannot emphasise enough.
An elevated Lp(a) is a RISK FACTOR for heart disease.
It does not mean you HAVE heart disease.
Familial Hyperlipidemia (FH).
FH is a genetic cholesterol disorder present in about 1 in 300 people3.
When people say they have ‘high cholesterol,’ they typically note Total Cholesterol figures of 5 to 6 mmol/L ( 200-230 mg/dl).
This is generally NOT the range we see in FH.
When someone starts quoting figures of 8 mmol/l (309 mg/dl) then we are starting to move into FH territory.
Although FH is a genetic disorder, diagnosing FH usually does not require a gene test.
The diagnosis is usually made by integrating LDL cholesterol lab tests, family history, and other physical signs, such as xanthelasma, which are cholesterol deposits on the skin.
With this information, the probability of FH can be calculated using various tools, including the Dutch Criteria for FH and others.
If there is still some uncertainty, gene testing can be done.
The key thing here is that LDL cholesterol levels can be lowered safely and effectively to substantially reduce the future risk of an early heart event.
Not treating FH is a major missed opportunity, given the tools we have to diagnose and treat it.
Again, this is why everyone should have a standard cholesterol test early in life.
This is not a disease of lifestyle; this is genetics, pure and simple.
The treatment, then, is not lifestyle; it is medications (And lifestyle).
Compared to Lp(a), there are many options for FH.
Don’t miss this one.
Other Genetic Risks.
There are other reasons someone can develop heart disease early in life.
Type 2 diabetes is one of the most significant risk factors for heart disease but also has very high levels of heritability.
If one parent has type 2 diabetes, the probability of one of their children having it also is about 40%.
If both parents have type 2 diabetes, the probability rises to 70%4.
But again, just because something is highly heritable, it does not mean it cannot be avoided with appropriate or aggressive lifestyle interventions.
High blood pressure is also highly heritable and a major risk factor for early heart disease.
It is estimated that 30 to 70% of high blood pressure has a genetic heritability5.
Risk Versus Disease
When it comes down to it most people are less interested in if they have the RISK FACTOR for early heart disease (Lp(a), FH etc.) and are much more interested in answering the question if they have the DISEASE that is coronary artery disease.
Because you can have lots of risk factors, even serious ones, but that does not mean you WILL develop heart disease early in life.
It certainly does increase the odds, but it does not guarantee it.
And even if we have been diligent in searching for specific genetic causes, there may be other unmeasured variables at play that have resulted in early heart disease.
And the amount of heart disease a person has is one of the best predictors of a heart event.
This is when we need to consider additional tests, such as cardiac CT, to look directly for the disease.
A cardiac CT scan is a CT scan of the heart that looks directly at the heart arteries to assess whether a person has heart disease and, if so, how much.
A CT CAC score of 0 means a person has no calcified coronary artery plaque and also means their risk of a heart attack over the next ten years is probably less than 2%.
On the other hand, if their CAC score is greater than 100, they have a considerable amount of calcified plaque and also a much higher risk of a heart attack over the next ten years6.
So regardless of risk factors, if someone has no calcified plaque in their coronary arteries, their risk of a heart attack over the NEAR term is low.
That is the question most people are looking for an answer to.
Their lifetime risk is a totally different story.
There are some major caveats when considering cardiac CT.
Firstly, if you are young and have a CT CAC score of 0, that is, of course, good news.
But it is exactly what we would expect.
It does not mean that any risk factors you have do not matter; it just means that they haven’t yet resulted in advanced visible plaque.
Secondly, and often the bigger issue, is the potential impact on life insurance.
When applying for life insurance, you must disclose all relevant medical test results (Genetic results are different and vary by geography).
But if you have a CAC score of 15 as a 35-year-old male, this means you are accumulating plaque and risk much earlier in life.
As a result, a life insurance company may choose to deny you life insurance or charge you a very hefty premium.
So, if you are still at the point of your life where you have not gotten life insurance or a mortgage (for which you will need separate life insurance) sorted, then you need to tread VERY carefully here.
My advice is to focus on aggressively treating any risk factors and assume you are at high risk until you can demonstrate otherwise.
Family History Is Not Fate
If you have an early family history of heart disease, you MIGHT be at an increased risk of early heart disease.
Might.
But I am not in the business of guessing.
The first thing to do is find out.
Do you REALLY have an early family history?
Was it heart disease or something else?
Were they all heavy smokers?
What specific risk factors do you have?
Do you have the disease? Not just the risk.
How aggressive do you need to be?
These are the questions I would be asking myself in the setting of an early family history of heart disease.
But most of all, you must remember that your family history is not destiny.
If a parent had a serious heart event at a young age, it does not mean that you will also.
And the earlier you can define and act on your risk, the better.
Genetic Risk, Adherence to a Healthy Lifestyle, and Coronary Disease. N Engl J Med. 2016 Dec 15;375(24):2349-2358.
A Test in Context: Lipoprotein(a): Diagnosis, Prognosis, Controversies, and Emerging Therapies. J Am Coll Cardiol. 2017 Feb 14;69(6):692-711.
What Is the Prevalence of Familial Hypercholesterolemia? Arterioscler Thromb Vasc Biol. 2021 Oct;41(10):2629-2631.
Genetics of type 2 diabetes-pitfalls and possibilities. Genes (Basel). 2015 Mar 12;6(1):87-123.
The genetics of blood pressure and hypertension: the role of rare variation. Cardiovasc Ther. 2011 Feb;29(1):37-45.
JACC: Cardiovascular Imaging May 2015, 8 (5) 579-596;
Brilliant and clearly stated as always. Thanks for this content.
I believe there's a mistype in the unit conversion of cholesterol here:
"When someone starts quoting figures of 8 mmol/l (10 mg/dl) then we are starting to move into FH territory."
Like many people, I had to insist on LP(a) testing. The test was not covered by insurance but it was inexpensive. Knowing that I do not have elevated LP(a) is valuable information. People need to be informed. The medical community will not do the work for us. Thanks for the article.