Know your cholesterol level to avert heart attack and stroke

Cholesterol is a term used to describe lipid molecules that deposit on the arterial wall and slowly cause narrowing, distortion or blockage of the blood vessels. The progressive plaque build-up and clot formation can cause heart attack, stroke and blockage of arteries. The deformation of the blood vessels also causes aneurysms of the aorta, which could rupture and lead to serious consequences, including death.

 Is cholesterol synonymous with body fat that causes obesity?

No. Indeed, many people are surprised when told their BMI (body mass index) is normal yet the blood cholesterol is high. On the other hand, some obese people may have normal blood cholesterol. The two differ in that the body fat that causes obesity is fat globules stored under the skin when the body cannot process excess fat; whereas blood cholesterol are lipoprotein particles that circulate in the blood and contribute to the development of plaque build-up in the arteries.

Is it true that elevated cholesterol causes heart attacks and stroke?

Multiple studies have consistently shown a clear correlation between the level of cholesterol and the likelihood of developing a heart attack or stroke. There is a clear correlation between the level of blood cholesterol and the extend of plaque build-up in the arteries. In addition, treatment of lipid disorders has been shown to lower possibility of heart attack and stroke.

The likelihood of developing heart attack increases in those who smoke, have hypertension or diabetes and those with family history of heart attack.

What causes lipid disorders?

Lipid disorders arise from a multiplicity of conditions. These include liver disease, excessive alcohol consumption, diabetes, thyroid disease, pancreatic disorders and genetic abnormalities. These are compounded by unhealthy dietary habits, sedentary lifestyle and genetics. Genetic abnormalities commonly run in families; and patients are particularly advised to have their cholesterol checked if heart attack has affected a first degree relative who is younger than 40 years for men and 50 years for women.

How do I know my cholesterol is elevated?

Many patients with elevated cholesterol are discovered for the first time after coming to the hospital with a heart attack or stroke. This is because lipid abnormalities can stay dormant for many years without causing harm. It is therefore imperative for one to measure their lipid levels in advance to determine if they are at risk. This is recommended annually for those with hypertension, diabetes and family history of heart disease or stroke. Some patients with high cholesterol levels may show some skin abnormalities around the eye or around the Achilles tendon — a fibrous band of tissue that links the muscles in your calf to your heel.

Are lipid disorders treatable?

Yes. The first line treatment for lipid disorders are lifestyle measures. These include exercise of at least 45 minutes for five days a week, and diet modification to avoid foods rich in saturated and trans-fats such as ham, bacon and deep fried fast foods. Foods that could help reduce cholesterol include fruits and vegetables (avocado, olives), nuts, legumes such as beans and lentils and white meat such as fish. Patients are advised to limit alcohol intake and avoid salt.

Physicians will commonly perform a risk stratification to determine the risk to the patient. Risk refers to the likelihood of developing a complication (heart attack, stroke, blocked artery) over the next 10 years. If the risk is high, then drug therapy is beneficial. These medications drop the level of cholesterol in the blood by preventing cholesterol synthesis and prevent further cholesterol deposition in the arteries. In addition, they cause existing plaque build-up to because more stable and less likely to rupture and cause heart attack or stroke. They have been shown to reduce heart attack and stroke in multiple clinical trials

How long is medication for cholesterol required?

Once someone has been diagnosed with a lipid disorder,  treatment is usually life-long. This means applying lifestyle measures and lifestyle modification. It is therefore imperative for the patient and physician to have a candid discussion about first line of therapy (lifestyle modification) and goals of therapy before medication is started. Once medication is withdrawn, the lipid levels rise to pre-medication levels and process of plaque build-up continues.

Dr Ngunga is a consultant interventional cardiologist at Aga Khan University Hospital