What is cardiovascular risk?

Cardiovascular risk is the probability — usually expressed over the next ten years — that someone will have a heart attack, a stroke, or die from a related cause. It’s a statistic, drawn from population data, that asks a useful but limited question: given who you are right now, how likely is something bad to happen by the time you’re a decade older?

That question is worth asking. Cardiovascular disease accounts for roughly one in four deaths in the UK [1], and most of those events happen to people who didn’t think they were at risk. But the standard answer — a single percentage from a calculator like QRISK3 in the UK or ASCVD in the US — is a starting point, not an ending one. To understand your real risk, you need to know what those calculators measure, and what they miss.

What standard risk calculators capture

The most widely used tool in UK primary care is QRISK3, recommended by NICE [2]. It combines over a dozen factors to produce a single ten-year risk estimate. Each input is doing different work, and it’s worth understanding what each one is actually measuring.

What QRISK3 considers:

• Age, sex, and ethnicity. Risk rises sharply with age and differs between men and women — men accumulate risk earlier, women catch up after menopause. Ethnicity matters too: people of South Asian, African, and Caribbean heritage carry higher cardiovascular risk at lower thresholds of other markers, and QRISK3 adjusts for this.
• Smoking status. Arguably the single most powerful modifiable risk factor in the calculator. Even five or ten years after quitting, the risk reduction is substantial — though it never quite returns to that of someone who never smoked.
• Diabetes and chronic kidney disease. Both damage the inner lining of blood vessels (the endothelium) and accelerate plaque formation. Type 2 diabetes roughly doubles cardiovascular risk independently of other factors. Chronic kidney disease has a similar effect through a different mechanism.
• Systolic blood pressure and its variability. High blood pressure imposes constant mechanical strain on artery walls, leading to thickening, stiffening, and damage. QRISK3 also accounts for variability — how much your blood pressure swings between readings — which independently predicts events even when the average looks acceptable.
• Total cholesterol to HDL ratio. This is the calculator’s lipid input. It’s a useful crude marker, but limited: it doesn’t separate the kinds of particles carrying the cholesterol, and it can disguise people whose absolute particle count is high. More on this below.
• Body mass index. A proxy for body composition. Useful at the extremes, but blunt — it doesn’t distinguish lean mass from fat mass, or where the fat sits. Visceral fat around the abdomen and liver is much more cardiovascularly damaging than peripheral fat, and BMI cannot see the difference.
• Family history of premature heart disease. If a parent or sibling had a heart attack or stroke before fifty-five in men or sixty-five in women, your inherited risk is materially higher. The calculator captures this fact, but it cannot capture what you’ve inherited. Some of that is Lipoprotein(a) — which we come back to below.
• Inflammatory and medication-related conditions. QRISK3 also adjusts for rheumatoid arthritis, lupus, severe mental illness, migraine, and use of corticosteroids or atypical antipsychotics. Each has been linked independently to higher cardiovascular risk, often through chronic inflammation or metabolic side-effects.

It is, on its own terms, a good tool. If your QRISK3 score is high, you are very likely at elevated risk, and standard medicine will act on it — usually with statins, blood pressure treatment, and lifestyle advice. But the score has known blind spots, and most of them matter most in people who look low or moderate risk on paper.

What standard assessments miss

A normal QRISK3 score does not mean no risk. It means no identifiable risk under the assumptions the calculator uses. Three categories of information are routinely absent from those assumptions.

Apolipoprotein B (ApoB) — what’s actually in your cholesterol number. Standard panels report LDL-C: the total amount of cholesterol carried in low-density lipoprotein particles. But cholesterol doesn’t form plaque. The particles carrying it do. Every atherogenic lipoprotein — LDL, VLDL, IDL, and Lp(a) — carries exactly one molecule of apolipoprotein B (ApoB) on its surface. Measure ApoB and you’re counting the number of plaque-forming particles in circulation. Measure LDL-C and you’re counting the cargo, not the trucks.

Why does the distinction matter? Because the two don’t always agree. Around a quarter of people show discordance — LDL-C and ApoB give different signals. The most concerning version is low LDL-C with high ApoB: a normal-looking cholesterol number, but many small, dense particles each carrying a light load. Each particle is still capable of depositing plaque. By LDL-C, you look fine. By ApoB, you’re not.

Multiple lines of evidence — including meta-analyses of statin trials and Mendelian randomisation studies — show ApoB is a stronger predictor of cardiovascular events than LDL-C [3, 4]. European guidelines now recommend ApoB as a preferred marker in many patients, especially those with high triglycerides, diabetes, or metabolic syndrome. It is not routinely measured by the NHS.

Lipoprotein(a) — the genetic risk most people don’t know they have. Lipoprotein(a), usually written Lp(a) and pronounced “L-P-little-a”, is a peculiar particle. It resembles LDL — cholesterol on an ApoB backbone — but with an extra protein bolted on called apolipoprotein(a). That extra protein looks chemically similar to plasminogen, the molecule your body uses to dissolve clots. The result is a particle that’s both pro-atherosclerotic (driving plaque) and pro-thrombotic (encouraging clot formation). Two cardiovascular insults in one.

Your Lp(a) level is roughly 80–90% genetically determined. It is set early in life and stays stable; lifestyle barely moves it. About one in five people globally — and disproportionately, those of African and South Asian heritage — carry elevated levels.

The consequences are significant. High Lp(a) raises the lifetime risk of heart attack, stroke, and aortic valve stenosis. It is invisible to QRISK3, invisible to a standard cholesterol panel, and is the most under-tested clinically important lipid marker in modern medicine [5].

Current treatment options are limited. Statins don’t meaningfully reduce Lp(a) — some can slightly raise it. PCSK9 inhibitors lower it by around 20–30%. New RNA-based therapies — drugs like pelacarsen and olpasiran — are in late-stage trials and could change the picture meaningfully within the next several years. For now, knowing your Lp(a) level once in adulthood is what matters. People with elevated Lp(a) are typically treated to lower ApoB targets, lower blood pressure targets, and earlier intervention thresholds, because their underlying risk is higher.

Coronary Artery Calcium scoring — looking directly at the artery. If everything above is indirect — markers, calculators, proxies — the coronary artery calcium (CAC) scan is direct. It’s a low-dose CT scan of the heart that detects and quantifies calcified plaque already present in the coronary arteries. The output is the Agatston score, a single number summarising the volume and density of calcified plaque present.

The scoring rubric is straightforward: zero means no detectable calcified plaque; one to one hundred is mild; one hundred to four hundred is moderate; over four hundred is severe.

A zero score, particularly in someone over forty-five, is one of the most reassuring findings in cardiology. The risk of an event over the next five to ten years is very low — what some cardiologists call a “warranty period” [6]. A high score, conversely, means atherosclerosis has already started, regardless of how clean your blood markers look. This is why CAC has moved into mainstream international guidelines for risk reclassification. Someone with a borderline QRISK3 and a CAC of zero often doesn’t need a statin. Someone with the same QRISK3 and a CAC of 200 almost certainly does — and probably should have been on one earlier.

The standard score answers “what’s your risk profile on paper?” The fuller assessment answers “what’s actually happening in your arteries?” Those are not the same question.

How modern risk assessment is changing

Internationally, the picture is moving. The 2019 European guidelines on dyslipidaemia recommend measuring Lp(a) at least once in adulthood, and ApoB as a preferred marker over LDL-C in many patients [3]. The 2018 American guidelines and updates since have given CAC scoring a central place in deciding who needs aggressive prevention [6]. These are not fringe positions; they are increasingly mainstream cardiology. They just haven’t yet filtered into how most people are assessed.

What that means in practice: if you’ve had a “normal” cholesterol panel and a QRISK3 score in the green, you have not had a comprehensive cardiovascular risk assessment. You’ve had a screening, against a population-level rubric, with most of the modern tools missing.

A more complete picture includes:

1. ApoB, alongside or in place of LDL-C
2. Lipoprotein(a), measured at least once
3. A coronary artery calcium score, particularly from the mid-forties onward
4. Detailed blood pressure assessment — at home, across the day, not just in clinic
5. Markers of metabolic health: fasting insulin, HbA1c, body composition

None of this is exotic. All of it is well-evidenced. Most of it is simply not done in the time and budget available to standard primary care.

What this means for you

Cardiovascular risk is not destiny. It’s a moving picture — shaped by genetics, but largely written by what you do over decades. The earlier you understand your own picture in detail, the more powerful the levers you can pull: blood pressure, ApoB, glucose, body composition, sleep, fitness, and — where indicated — medication that starts earlier and is targeted more precisely. The data on early, sustained intervention is overwhelming [7].

What changes when you assess properly isn’t usually drama. It’s clarity. Most members come out of a comprehensive cardiovascular workup with a clear answer to two questions: how worried do I actually need to be, and what are the two or three things that will move the needle most in my case. From there, the work is sustained and quiet — measured every year, reviewed with continuity, adjusted over time. Not catching up to risk, but staying ahead of it.

References

1. British Heart Foundation. UK CVD Statistics Factsheet. London: BHF, 2024.
2. Hippisley-Cox J, Coupland C, Brindle P. Development and validation of QRISK3 risk prediction algorithms to estimate future risk of cardiovascular disease: prospective cohort study. BMJ 2017;357:j2099.
3. Mach F, Baigent C, Catapano AL, et al. 2019 ESC/EAS Guidelines for the management of dyslipidaemias. European Heart Journal 2020;41(1):111–188.
4. Sniderman AD, Thanassoulis G, Glavinovic T, et al. Apolipoprotein B Particles and Cardiovascular Disease: A Narrative Review. JAMA Cardiology 2019;4(12):1287–1295.
5. Nordestgaard BG, Chapman MJ, Ray K, et al. Lipoprotein(a) as a cardiovascular risk factor: current status. European Heart Journal 2010;31(23):2844–2853.
6. Greenland P, Blaha MJ, Budoff MJ, et al. Coronary calcium score and cardiovascular risk. Journal of the American College of Cardiology 2018;72(4):434–447.
7. Visseren FLJ, Mach F, Smulders YM, et al. 2021 ESC Guidelines on cardiovascular disease prevention in clinical practice. European Heart Journal 2021;42(34):3227–3337.