New Risk Factors for Heart Disease:

Mr. Sunil Shah is a 40-year-old trader, who used to walk daily for one hour, is a pure vegetarian, and does not smoke or drink alcohol.  He does not have diabetes or high blood pressure and his cholesterol was ‘borderline high’.

Last week he had a massive heart attack at 6 am on Monday morning, and had to have a bypass surgery within three days.  After his recovery, he went into severe depression because he found it difficult to accept as to how a ‘healthy’ person like himself could have a heart attack.

Mr. Shah did not have the well-established risk factors of smoking, diabetes, blood pressure and high cholesterol.  After doing detailed investigations, it was found that he had a high homocysteine level and a high Lipoprotein (a) level.  These proteins have been discovered in the past few years and are known as new risk factors for heart disease.

In studies done on Indians living in England and North America it has been seen that they have high levels of both these conditions and are therefore more prone to heart disease.  It is therefore even more important to keep our risk factors in control.

Homocysteine –

Homocysteine is a common amino acid (one of the building blocks that make up proteins) found in the blood. High levels of homocysteine are related to the early development of heart disease. High homocysteine is associated with low levels of vitamin B6, B12 and folic acid and renal disease.

Levels of the amino acid are related partly to a genetic mechanism and diet.   The good news is that diet, especially one high in folic acid and B vitamins, favorably affects the levels of homocysteine.

How Does Homocysteine Increase Heart Disease Risk?

Doctors believe that homocysteine may contribute to the buildup of fatty substances in the arteries, increase the stickiness of blood platelets (clotting), and make blood vessels less flexible, less able to widen to permit increased blood flow.  

Do I Need to Have My Homocysteine Level Checked?

Currently, there is no universal recommendation for checking homocysteine in everyone. The test is still relatively expensive and isn't widely available. However, testing for homocysteine is useful in people with other risk factors for heart disease or those who have a personal or family history of cardiovascular disease, but do not have any of the standard risk factors.  The normal blood level of homocysteine is 5-15 micromoles per liter.

Can High Homocysteine Levels Be Prevented? 

Patients with high homocysteine levels can increase their intake of B-vitamins (folic acid, vitamins B-12, and B-6) through supplements or a diet rich in fruits, green leafy vegetables, and whole grains. While doing this will successfully lower the homocysteine number on a blood test, it is crucial to note that large-scale clinical trials have not shown that this actually reduces the risk of having a heart attack. Therefore, lowering homocysteine is no longer considered a primary target for cardiovascular treatment compared to more critical factors like Lp(a) or ApoB.

Lipoprotein (a)

Lipoprotein(a) is a major, independent, and genetically inherited risk factor for cardiovascular disease. It is essentially a variant of "bad" LDL cholesterol attached to an extra protein particle, making it particularly "sticky." One study estimates that each Lp(a) particle can be up to 6.6 times more atherogenic (plaque-causing) than normal cholesterol.

Do I Need to Have My Lipoprotein (a) Level Checked? Yes. The medical consensus has completely changed on this in recent years. The 2026 ACC/AHA Dyslipidemia Guidelines now explicitly issue a Class 1 recommendation that every adult have their Lp(a) measured at least once in their lifetime. Because it is genetically determined, it will generally remain stable throughout your life, so one test is usually sufficient. It is especially critical to test if you have a family history of early heart disease. The normal blood level of lipoprotein (a) is generally considered to be less than 30 mg/dL (or <75 nmol/L).

Can High Lipoprotein (a) Levels Be Prevented? Lp(a) is largely an inherited risk factor and cannot be prevented through lifestyle or diet. However, if your Lp(a) is high, it is extremely important to work with a cardiologist to aggressively lower your standard LDL cholesterol and manage all other risk factors. While standard statins do not lower Lp(a), newer, advanced therapies like PCSK9 inhibitors are now recommended in the 2026 guidelines for specific high-risk patients to help manage this condition. Furthermore, if you test high, your first-degree relatives (parents, siblings, children) should immediately be tested as well.

Apolipoprotein B (ApoB) In addition to Lp(a), modern 2026 guidelines highly recommend testing for Apolipoprotein B (ApoB). While a standard lipid panel measures the weight of cholesterol in your blood, ApoB measures the actual number of plaque-causing particles. Many individuals—especially South Asians and those with metabolic syndrome—can have a "normal" LDL cholesterol number but a dangerously high number of ApoB particles, meaning they are at a high risk for a heart attack without knowing it.

As Mr. Shah’s story shows, a healthy lifestyle and normal standard cholesterol do not always tell the whole story. Hidden genetic markers like Lp(a) and ApoB can elevate your risk without warning. Don't wait for a wake-up call—ask your cardiologist about testing for these specific proteins so you can take proactive steps to protect your heart.

Author: Dr. Aashish Contractor is India's pioneer in cardiac rehabilitation and the Founding Medical Director of the Mumbai Marathon. With over 25 years of experience, he has guided hundreds of heart patients to run safely.