LDL cholesterol

LDL cholesterol, known as “bad” cholesterol, is the main modifiable indicator of heart attack and stroke risk. The test shows how much is in your blood and whether you have reached the target set by your doctor. High LDL does not hurt or cause symptoms, so it is detected only through a blood test.

Who the test is for

• adults as part of cardiovascular risk assessment, on a doctor’s recommendation;
• people who smoke or have high blood pressure, diabetes, kidney disease or excess weight;
• people whose close relatives had high cholesterol or a heart attack or stroke at a young age;
• people taking statins or other cholesterol medications, to monitor their effect;
• after a heart attack or stroke, when the target is very low LDL;
• women after menopause, when LDL often rises.

What the test reveals

Cholesterol travels through the blood in particles called lipoproteins. LDL particles carry cholesterol to tissues, and excess gradually deposits in artery walls over the years, forming atherosclerotic plaques. The higher LDL is and the longer this lasts, the greater the risk, so LDL is the main target of blood lipid treatment.

For a complete picture, LDL is interpreted alongside total cholesterol, HDL cholesterol and triglycerides. European guidelines also recommend measuring at least once in a lifetime lipoprotein(a), whose level is largely inherited.

The procedure and preparation

Blood is taken from a vein, and the draw takes a few minutes. Come fasting, after 8 to 12 hours without food, with water only, as for other blood lipids. LDL changes little after a meal, but a fasting result is more reliable and easier to compare with previous ones.

Avoid alcohol and a large, fatty meal the day before. Take cholesterol medicines as usual unless your doctor says otherwise.

What your result means

There is no single “good” value for everyone. Your doctor assesses your overall risk according to age, sex, blood pressure, smoking, diabetes, kidney function and family diseases, then sets a personal target. European guidelines (ESC/EAS) give these targets:

• low risk: below 3,0 mmol/L;
• moderate risk: below 2,6 mmol/L;
• high risk: below 1,8 mmol/L and at least half the baseline value;
• very high risk, for example after a heart attack or stroke: below 1,4 mmol/L and at least half the baseline value.

The reference interval printed on the report applies, but your personal target is more important for treatment decisions.

• Elevated LDL is most often due to heredity, a diet rich in saturated fats, excess weight and too little exercise. Underactive thyroid, diabetes and kidney disease also increase it, so your doctor often also checks TSH. LDL above 5 mmol/L, particularly with early heart disease in the family, may suggest inherited (familial) hypercholesterolaemia.
• Low LDL is expected with cholesterol medication and is generally favourable. Without medication, an overactive thyroid, severe liver disease or malnutrition rarely lower it.

How to arrange testing

You can have blood taken without an appointment or referral at one of our branches across Croatia (listed under Contact). Prices for all tests and panels are available in the price list. LDL is most informative in the Lipid profile panel, which also includes total and HDL cholesterol and triglycerides from the same blood draw.

Frequently asked questions

What should LDL cholesterol be?

It depends on your risk. For a healthy low-risk person, LDL below 3,0 mmol/L is desirable; after a heart attack, the target is below 1,4 mmol/L. Agree your target with your doctor.

Can I lower LDL without medication?

Partly. Less saturated fat (fatty meat, full-fat dairy products, cakes), more vegetables, legumes, whole grains and nuts, regular exercise and losing excess weight lower LDL. Whether medication is also needed depends on your risk.

Why is my LDL high even though I eat healthily?

LDL levels depend largely on heredity. Even young, slim people with healthy habits can have high LDL, particularly with familial hypercholesterolaemia. Early treatment and checking close relatives are then important.

How often should LDL be checked?

Usually four to twelve weeks after starting treatment or changing the dose, then annually once the target is reached or as agreed with your doctor. Without treatment, frequency depends on age and risk.