ASCVD, or atherosclerotic cardiovascular disease, develops when fatty deposits called plaque build up inside your artery walls, narrowing them over time. This umbrella term covers coronary heart disease (including heart attacks and angina), stroke, peripheral artery disease, and aortic aneurysms. The risk factors that drive plaque buildup fall into two categories: ones you can change and ones you can’t.
High LDL Cholesterol
LDL cholesterol is the single most important lipid marker for ASCVD risk. Often called “bad” cholesterol, LDL particles deposit directly into artery walls and fuel plaque growth. For adults, the thresholds work like this: an LDL level of 190 mg/dL or higher is classified as severe and warrants treatment regardless of other factors. Levels between 160 and 189 mg/dL are considered a risk-enhancing factor that signals high lifetime risk. For adults aged 40 to 75, treatment discussions typically begin when LDL is at or above 70 mg/dL and estimated 10-year risk reaches 7.5% or higher.
Children and adolescents have their own scale. An LDL below 110 mg/dL is considered acceptable, 110 to 129 mg/dL is borderline, and 130 mg/dL or above is abnormal. Catching elevated cholesterol early matters because plaque buildup begins decades before symptoms appear.
High Blood Pressure
Sustained high blood pressure damages artery walls, making them more susceptible to plaque deposits. The American Heart Association defines the categories as follows:
- Normal: below 120/80 mm Hg
- Elevated: 120 to 129 systolic with diastolic still below 80
- Stage 1 hypertension: 130 to 139 systolic or 80 to 89 diastolic
- Stage 2 hypertension: 140 or higher systolic, or 90 or higher diastolic
Each step up in blood pressure category increases the mechanical stress on your arteries. Hypertension prevalence more than doubles as body weight rises: roughly 13% of normal-weight women have high blood pressure compared to 32% of those with severe obesity.
Diabetes and Blood Sugar
Diabetes is one of the strongest ASCVD risk factors. Chronically elevated blood sugar damages blood vessels from the inside, accelerates plaque formation, and promotes inflammation. The American Diabetes Association defines prediabetes as an HbA1c between 5.7% and 6.4%, while an HbA1c of 6.5% or higher meets the threshold for diabetes. Both prediabetes and diabetes carry increased cardiovascular risk in men and women.
The connection between weight and diabetes helps explain why these risk factors tend to cluster. Among normal-weight men, about 10% have type 2 diabetes. Among men with severe obesity (BMI above 40), that figure jumps to nearly 36%. For women, the gap is even steeper, rising from 5% to roughly 29%.
Smoking
Smoking damages the lining of your arteries, raises blood pressure, reduces the oxygen your blood can carry, and makes blood more likely to clot. Current smokers face two to four times the risk of coronary heart disease and two to four times the risk of stroke compared to nonsmokers.
The good news is that quitting reverses much of the damage on a surprisingly clear timeline. Heart attack risk drops sharply within one to two years of quitting. After three to six years, the added risk of coronary heart disease falls by half. Stroke risk decreases over five to ten years. And after 15 years without cigarettes, coronary heart disease risk drops to nearly the same level as someone who never smoked.
Excess Weight
Higher body weight is linked to unfavorable changes in blood sugar, cholesterol, inflammation, and blood pressure, all of which feed into ASCVD risk. One large population study found that each BMI category above normal weight was associated with a shorter ASCVD-free life span: about two years shorter for men and about one year shorter for women per category. Notably, some cardiovascular risk markers began shifting in an unfavorable direction even within the normal-weight range (BMI 20 to 25), suggesting the relationship between body composition and heart health is a continuum rather than a simple cutoff.
Where you carry fat also matters. Abdominal fat, sometimes measured by waist circumference, is considered more metabolically harmful than fat stored in the hips or thighs because it surrounds and infiltrates internal organs, driving inflammation and insulin resistance.
Age and Sex
Age is the single strongest driver of ASCVD risk. Plaque accumulates over decades, so the longer your arteries are exposed to even modest levels of cholesterol and blood pressure, the greater the total burden. European cardiovascular guidelines use progressively higher risk thresholds for each age bracket: what counts as “high risk” for someone under 50 (a 10-year event risk of 2.5% or more) is considered only moderate risk for someone over 70.
Biological sex plays a role too. Men tend to develop ASCVD roughly a decade earlier than women, partly due to the protective effects of estrogen on blood vessels before menopause. For risk-stratification purposes, a male first-degree relative who had a heart attack or stroke before age 55, or a female relative before age 65, qualifies as a premature family history of ASCVD.
Family History and Genetics
A family history of premature ASCVD is a risk-enhancing factor used in clinical guidelines. “Premature” means a first-degree relative (parent or sibling) who developed cardiovascular disease before age 55 in men or before age 65 in women. This criterion captures shared genetics, including inherited tendencies toward high cholesterol, high blood pressure, or diabetes, as well as shared lifestyle patterns.
Certain genetic conditions raise risk dramatically. Familial hypercholesterolemia, for example, can push LDL levels above 190 mg/dL from birth, leading to heart attacks in early adulthood if untreated.
Additional Risk-Enhancing Factors
Beyond the major risk factors, clinicians look at several secondary markers to refine your risk profile, particularly when your estimated risk falls in a borderline or intermediate range:
- Chronic kidney disease: reduced kidney function (estimated filtration rate between 15 and 59 mL/min) independently raises cardiovascular risk through inflammation, abnormal calcium metabolism, and fluid retention.
- High-sensitivity C-reactive protein: a blood marker of systemic inflammation. Levels at or above 2.0 mg/L are considered risk-enhancing.
- Lipoprotein(a): a genetically determined cholesterol particle that promotes clotting and plaque growth. Levels at or above 50 mg/dL (or 125 nmol/L) signal elevated risk. Unlike regular LDL, lipoprotein(a) levels are largely inherited and don’t change much with diet or standard cholesterol-lowering approaches.
How These Factors Are Combined Into a Risk Score
Doctors don’t evaluate these risk factors in isolation. The standard tool in the United States is the Pooled Cohort Equations calculator, available through the American College of Cardiology. It estimates your 10-year probability of a heart attack or stroke using your age, sex, race, total cholesterol, HDL (“good”) cholesterol, systolic blood pressure, whether you’re on blood pressure medication, diabetes status, and smoking status. The calculator works for adults aged 40 to 79 for 10-year risk, and ages 20 to 59 for lifetime risk.
Your score places you into one of four risk tiers: low (below 5%), borderline (5% to 7.4%), intermediate (7.5% to 19.9%), or high (20% or above). If your score lands in the borderline or intermediate zone, the risk-enhancing factors listed above, along with a coronary calcium scan, can tip the decision toward or away from starting preventive treatment. The value of this approach is that a single moderately elevated risk factor may not warrant intervention on its own, but several modest risk factors together can add up to a meaningfully higher chance of a cardiovascular event.