CHD on a blood test stands for coronary heart disease. It’s not a single measurement but rather a risk assessment that uses several blood values together to estimate how likely you are to develop heart disease. When you see CHD referenced on lab results, it typically appears as a risk score or ratio calculated from your cholesterol numbers.
What CHD Actually Measures
Coronary heart disease is a narrowing of the blood vessels that supply oxygen to your heart. Blood tests can’t directly detect this narrowing, but they can measure substances in your blood that strongly predict whether it’s happening or likely to happen. The main blood values used to assess CHD risk are:
- Total cholesterol: ideally below 200 mg/dL
- LDL cholesterol (“bad” cholesterol): below 130 mg/dL for most people, below 100 mg/dL if you have diabetes or other risk factors
- HDL cholesterol (“good” cholesterol): above 40 mg/dL for men, above 50 mg/dL for women
- Triglycerides: below 150 mg/dL
Some labs also measure a protein called high-sensitivity C-reactive protein, which reflects inflammation in your blood vessels. A level above 2.0 mg/L signals higher heart disease risk.
The CHD Risk Ratio on Your Lab Report
One of the most common places you’ll see “CHD” on a lab printout is next to a ratio comparing your total cholesterol to your HDL cholesterol. This ratio is a quick snapshot of your cardiovascular risk. You get it by dividing your total cholesterol by your HDL number.
A ratio below 3.5:1 is considered very good. Most doctors want to see it below 5:1. The higher the ratio, the higher your risk, because it means you have a lot of total cholesterol relative to the protective HDL type that helps clear fatty buildup from your arteries.
How Your 10-Year Risk Score Is Calculated
Beyond simple ratios, doctors use a more comprehensive tool to estimate your chance of developing heart disease over the next 10 years. The standard calculator, developed by the American College of Cardiology and the American Heart Association, combines your blood test results with other personal information: age, sex, race, total cholesterol, HDL cholesterol, systolic blood pressure, whether you take blood pressure medication, whether you have diabetes, and whether you smoke.
The result is a percentage. Someone with a 10-year risk below 5% is considered borderline or low risk. A score between 5% and 10% is intermediate. At 10% or higher, you’re in the high-risk category, and your doctor will likely recommend more aggressive cholesterol management. This is often the number labeled “CHD risk” or “ASCVD risk” on your results.
Target Cholesterol Levels Based on Your Risk
Your ideal cholesterol numbers depend on where you fall on that risk spectrum. The most recent guidelines from the American Heart Association and American College of Cardiology, published in 2026, set specific LDL targets for different groups:
If you’re at borderline or intermediate risk (3% to under 10% over 10 years), the goal is an LDL below 100 mg/dL. If you’re at high risk (10% or above), the target drops to below 70 mg/dL. And if you already have established heart disease, the target is even lower: below 55 mg/dL. These are tighter targets than many people expect, and they reflect strong evidence that lower LDL levels translate directly into fewer heart attacks and strokes.
People with diabetes face their own category. Adults aged 40 to 75 with diabetes but no existing heart disease are generally advised to aim for LDL below 100 mg/dL, even if their overall risk score seems moderate.
A More Precise Marker Most Labs Don’t Run
Standard lipid panels measure LDL cholesterol, but there’s a more accurate predictor of heart disease that most labs don’t include: apolipoprotein B, or apoB. This protein sits on the surface of every cholesterol particle that can build up in artery walls, so it gives a direct count of how many dangerous particles are circulating rather than just measuring the cholesterol they carry.
In about 18% of people, LDL cholesterol and apoB tell different stories. A large analysis of UK Biobank data found that when the two measurements disagreed, apoB predicted heart disease risk but LDL cholesterol did not. Despite this, apoB testing hasn’t become routine. If your LDL looks fine but you have other risk factors (family history, metabolic syndrome, high triglycerides), asking about apoB testing can give a clearer picture.
Do You Need to Fast Before the Test?
Traditionally, lipid panels require an 8- to 12-hour fast to get accurate readings. That’s still the preferred approach if your doctor is focusing on LDL cholesterol or total cholesterol, because eating can temporarily shift those numbers. However, HDL cholesterol, the total-to-HDL ratio, and triglycerides change only minimally in a nonfasting state, so some doctors now accept nonfasting samples for initial screening.
If your lab report is specifically calculating a CHD risk score or ratio, fasting gives the most reliable input values. When in doubt, skip food and drink anything other than water for at least 8 hours before your blood draw. Black coffee technically breaks a fast for lipid testing purposes because it can slightly alter triglyceride levels.
What an Abnormal CHD Risk Result Means
An elevated CHD risk score doesn’t mean you have heart disease right now. It means the combination of your blood markers and personal health factors puts you at higher-than-average odds of developing it. The practical next steps depend on how high your risk is and which specific numbers are off.
For many people, the first intervention is lifestyle changes: reducing saturated fat intake, increasing physical activity, and losing weight if needed. These steps alone can lower LDL by 10% to 15% in some cases. If your risk is high enough, or if lifestyle changes don’t move the numbers enough, medication becomes part of the conversation. The specific thresholds for starting treatment are tied directly to the risk categories and LDL targets outlined above.
Repeat testing is typically done every 4 to 12 weeks after starting treatment to check whether your numbers are moving toward target, then annually once they’re stable. If your initial results were normal, most adults should have a lipid panel repeated every 4 to 6 years, or more often if they have risk factors like family history or diabetes.