The Cholesterol Story

Heart attacks and brain strokes are very important cause of mortality in up to 80% cases worldwide. We in India have additional peculiarities. These are that the average age of an Indians at the time of an attack is younger than the global average and the illness runs a very rapid course with high fatality.

Although there are several risk factors explaining this phenomenon, high levels of cholesterol and its components exceed high blood pressure, diabetes, over weight and obesity. Smoking however tops the list. 

Facts about Cholesterol:

Cholesterol is a fatty substance produced by the liver that performs or assists in several important functions such as building cell membranes, nerve sheaths, and much of your brain. It’s vital to hormone production and metabolizes all the fat-soluble vitamins like vitamin A, D, E and K, among other things. It is thus essential for life.

Dietary cholesterol (cholesterol from food) can only be obtained from animal products like meat, milk, yogurt and eggs. Dietary cholesterol however, only makes upto 20 percent of the cholesterol in the blood.

Cholesterol has several sub-fractions:

1.Low density lipoprotein cholesterol (LDL C) picks up cholesterol from the liver and deliver it to cells. It circulates in the blood, moving cholesterol around the body to where it is needed for cell repair and depositing it inside of artery walls. Therefore, the lower it is the better it is.

High levels however become counterproductive and makes people prone to produce clogging of arteries resulting in heart attacks and strokes.

2.HDL (good) cholesterol is large, light and fluffy. HDL c removes excess cholesterol from the blood and take it back to liver. This phenomenon is also called reverse transport. 

Normal and Abnormal Levels of Cholesterol in the blood in adults:

Cholesterol:

In both sexes: Normal 125-200 mg/dl, Borderline 201-239 mg/dl, High greater than 240 mg/dl

LDL Cholesterol:

In both sexes Normal; Less than 100 mg/dl, Borderline 130-159 and High 160-189.

HDL Cholesterol:

Males Optimal more than 40 mgs/dl

Females; Optimal More than 50 mgs/dl

In individuals who are less than 20 years of age the levels should be lower than the levels given above in each category. 

How often should Lipid profile be done in adults:

High cholesterol usually has no symptoms. This is why it’s important to get your cholesterol levels checked. According to the Centres for Disease Control and Prevention (CDC) USA, most healthy adults should get their cholesterol checked every four to six years.

Your risk factors also determine how often your cholesterol should be checked. Adults who have a history of high cholesterol, heart disease, diabetes, or obesity need more frequent readings. Because older adults are more vulnerable to these conditions, they may be checked annually during a routine physical examination.

Children should have their cholesterol checked at least once between the ages of 9 and 11 and again between 17 and 20 years of age. 

How to reduce cholesterol levels

Children and adults benefit from getting regular exercise, maintaining a healthy weight, and eating a well-balanced diet rich in fibre. Exercise in the form of equivalent to walking more than 8000 steps per day is a very useful adjunct. It is always prudent to watch your weight.

Eat fruits, vegetables, nuts and seeds in plenty to reduce your bad cholesterol and increase your good cholesterol (HDL) levels. Studies have shown that a diet rich in plants, such as fruits, vegetables, nuts, seeds, whole grains, and legumes, can reduce the risk of heart disease, stroke and death.

Fruits and vegetables are rich in fibre which acts like a sponge, binding to cholesterol and helping clear it from the body. In general, consuming 2 cups of fruits and 3 cups of vegetables per day is recommended. Besides this reduce the amount of saturated fats and trans fats. These are contained in high quantities in pure milk, butter, egg yolks, mutton, beef. Poultry and fish have much lower contents of saturated fats. 

Who need drugs to bring down cholesterol levels:

With the availability of potent and safe agents it is easy to reduce the cholesterol levels to extremely low levels. Most often used drugs are from the statin group (atorvastatin and rosuvastatin). In addition, we have ezetimibe and a recently released agent bempedoic acid. We also have injectable agents for very high-risk patients: Evolocumab needing a fortnightly injection and Inclesaran requiring a six-monthly injection.

Accepted indications for atorvastatin/ rosuvastatin use:

1.All patients with a history of a coronary event like myocardial infarction, unstable or stable angina, patients who have undergone an angioplasty with or without a stent or coronary artery bypass surgery.

2.Patients with a history of a brain stroke or transient ischemic attack.

3.Patients with disease of limb arteries leading to claudication or associated symptoms.

4.Extremely high levels of LDL c (160 mgs/lit)

In these situations, statins in adequate doses lead to reduction of CV events by 25 to 40%. In general statins are well tolerated even in high doses. A study done by the author has shown that the highest dose of 80 mgs of atorvastatin is tolerated very well like the 40 mgs in Indian patients. Side effects like muscle pains necessitating reduction of dose or stoppage is very low.

There has often been a discussion regarding cataracts, dementia, development of diabetes after prolonged use. In general, the benefits of these group of drugs far outweigh the side effects and secondary issues. So remarkable is the effect on lowering heart attacks and strokes that these drugs have been compared to penicillin for treating infections when the drug was discovered in 1930’s. Incidentally statins came into clinical use in 1987.

Bempedoic acid another potent agent recently introduced is devoid of muscle pains and can be used as an alternative and can also be combined with statins in those patients where levels need to be lowered further.

Situations in which injectable drugs are needed:

Patients at extremely high risk. Individuals who got recurrent heart attacks (more than 1 attack despite full medication within a year). These patents need to have LDL cholesterol levels less than 55 mgs/dl. At times statins and oral combinations are unable to do it.

Familial dyslipidaemias with early heart attacks

Heart attacks at young ages when we need LDL cholesterol levels at very low levels preferably around 30 to 35 mgs/dl.

Both Evolocumab and Inclisiran can achieve these extremely low levels very predictably. These agents are also indicated in persons who have diffuse blockages in their heart, brain and limb arteries all together making them very prone to recurrences. Cost is a factor when using them but a life saved can be priceless and invaluable.

Prof Upendra Kaul, Founder Director Gauri Kaul Foundation