What should I do if my cholesterol is high? How can I lower it?

Many people have heard of the three highs and know the harms of high blood pressure and high blood sugar: severe hypertension can cause stroke, myocardial infarction, renal failure, etc.; diabetes (long-term high blood sugar) causes chronic damage and dysfunction of the eyes, kidneys, heart, blood vessels, and nerves. But what is the other high?

Many people don't know. That is high blood lipids , which are harmful to people. High blood lipids can lead to obesity, cardiovascular, liver disease, kidney disease and a series of worrying diseases. What causes hyperlipidemia? You are right, it is cholesterol. Is cholesterol bad? How to lower cholesterol? Let's talk about it today!

01. Is all cholesterol bad?

Blood lipids are the general term for cholesterol, triglycerides and lipids in the serum[1]. If the cholesterol level is high , it may cause dyslipidemia [1].

But does cholesterol have no good side at all? That can't be generalized. There are two types of cholesterol in the human body: high-density lipoprotein cholesterol (HDL-C), commonly known as "good cholesterol", and low-density lipoprotein cholesterol ( LDL-C ), commonly known as " bad cholesterol ". The specific "good" and "bad" are clear at a glance when you look at the picture below.

"Good" cholesterol works hard to reduce blood vessel blockage, while "bad" cholesterol keeps causing trouble and clogging blood vessels.

The consequence of "bad" cholesterol is that blood cannot pass through blood vessels. (Image from: Sohu)

How to distinguish good cholesterol from bad cholesterol? Generally, the test report will indicate HDL-C (good cholesterol) and LDL-C (bad cholesterol). If LDL-C is elevated, it is necessary to pay attention and sound the alarm. But don't panic, have regular blood lipid tests, and if cholesterol is high, take preventive measures as soon as possible.

The picture comes from: Screenshot of BTV's "Health Hall" program. If there is any inappropriateness, please contact us to delete it.

Let’s talk about at what specific value the “bad” cholesterol is considered “bad”, that is, what are the prevention and control standards?

02. What are the prevention and control standards for cholesterol?

For ordinary people (primary prevention of ASCVD), please refer to the following figure:

Guidelines for the prevention of dyslipidemia in Chinese adults (2016 revised edition)[1]

However, for those with a history of atherosclerotic cardiovascular disease (ASCVD) (including coronary heart disease, stroke, peripheral vascular disease, etc.), the goal of controlling cholesterol is different:

Guidelines for the prevention of dyslipidemia in Chinese adults (2016 revised edition)[1]

More and more people in the medical community believe that “ the lower the LDL-C, the better .” For example, the 2015 IMPROVE-IT study found that the risk of cardiovascular events could be further reduced if LDL-C was reduced from 1.8mmol/L (69.5mg/dl) to 1.39mmol/L (53.7mg/dl)[2].

03. How to lower cholesterol?

I think there are two main aspects to start with:

1. Diet therapy and lifestyle changes. Does diet affect cholesterol? Of course. Changes in dietary patterns and increased intake of animal foods are indisputable causes of elevated cholesterol.

However, current research has shown that the relationship between blood cholesterol and dietary cholesterol is not close. Therefore, the U.S. Dietary Guidelines and the "Dietary Reference Intakes for Chinese Residents" no longer simply limit the intake of dietary cholesterol, but instead emphasize dietary balance, nutritional balance, and changing unhealthy lifestyle habits [3]-[4].

Willett's Healthy Food Pyramid

2. Statins: Lipid-lowering drugs such as statins have a very good effect on the primary and secondary prevention of cardiovascular disease and can significantly reduce the risk of cardiovascular disease.

However, statins are less effective in treating some high-risk patients[5], and can cause adverse reactions in the liver, muscles, and other areas in people who are intolerant. There is also a " 6% effect of statin efficacy " or " statin 6 principle ", which states that doubling the dose of statins only further reduces LDL-C by about 6%[1].

[6]-[7]

04. What should I do if statins cannot bring cholesterol levels up to standard?

If statins are unable to bring cholesterol levels up to target, a combination of statins and ezetimibe can be tried, which has a good lipid-lowering effect. Studies have shown that this approach can further reduce blood lipids by about 18% on the basis of statin treatment[1]. However, among patients who have received lipid-lowering treatment, a considerable number of patients' cholesterol levels cannot reach target levels[8].

Now, an innovative and highly safe biological monoclonal antibody has been launched on the market, which can solve the bottleneck problem of traditional cholesterol-lowering drugs. It is a PCSK9 inhibitor . It can further reduce LDL-C levels by 50%-60% on the basis of statin treatment[9].

How does it do this? Here we have to introduce another "good guy" in the blood: the low-density lipoprotein (LDL) receptor (LDLR). The "good guy" LDLR can remove "bad" cholesterol[10]. But once PCSK9 binds to LDLR, it is difficult to eliminate "bad" cholesterol. Therefore, PCSK9 inhibitors are used to inhibit the binding of PCSK9 and LDLR and control the overall level of "bad" cholesterol[10].

This PCSK9 inhibitor, which protects the "good guy" and removes the "bad" cholesterol, can significantly reduce LDL-C levels and improve other blood lipid indicators with good safety [11]. A study called FOURIER showed that if statins are combined with PCSK9 therapy, LDL-C levels can be reduced to extremely low levels, cardiovascular events can be further reduced, and safety is good[12].

So, is high cholesterol a problem? The key is to look at the "bad" cholesterol (LDL-C) value, which is an important risk factor for cardiovascular disease; how to lower cholesterol? Going to bed and getting up early, eating healthy, and exercising are the basics. If necessary, consult a doctor to see if medication is needed.

It is worth adding that at the 2017 ACC (American College of Cardiology) Asia Pacific Conference, Professor Anthony Keech announced that PCSK9 inhibitors are equally effective in reducing the risk of cardiovascular events in Asians compared with other populations, and the safety data are comparable [13]. Patients in need can consult their doctors.

[1] Joint Committee on the Revision of the Guidelines for the Prevention and Treatment of Dyslipidemia in Chinese Adults. Guidelines for the Prevention and Treatment of Dyslipidemia in Chinese Adults (2016 Revised Edition) [J]. Chinese Journal of Cardiovascular Diseases, 2016, 44(10): 833-853. DOI: 10.3760/cma.j.issn.0253-3758.2016.10.005

[2] Outpatient Clinic. New Perspective on Blood Lipids | Peng Daoquan: Analysis of the Viewpoint of “Lower LDL-C is Better” and Discussion on Practical Strategies. New Perspective on Outpatient Clinic, 2017.

[3] US Department of Health and Human Services and US Department of Agriculture. 2015–2020 Dietary Guidelines for Americans. 8th Edition. December 2015.

[4] Chinese Preventive Medicine Association Health Communication Branch, Chinese Preventive Medicine Association Chronic Disease Prevention and Control Branch, etc. Correctly understand the scientific statement of cholesterol, 2016: 3.

[5] Aggarwal J, et al. Abstract from AMCP Managed Care & Specialty Pharmacy Annual Meeting 2016, April 19-22 2016; San Francisco, CA.

[6] Knopp RH.N Engl J Med. 1999;341 (7):498-511.

[7] Stein E. Am J Cardiol 2002;89(5A): 50C-57C.

[8] Zhao S, Wang Y, et al., Prevalence of dyslipidaemia in patients treated with lipid-lowering agents in China: results of the DYSlipidemia International Study (DYSIS), Atherosclerosis (2014), doi: 10.1016/j.atherosclerosis.2014.05.916

[9] Sabatine MS, Giugliano RP, Keech AC et al. Evolocumab and Clinical Outcomes in Patients with.

[10] Shen Li, Zhao Shuiping. Current status of research on new lipid-lowering drugs PCSK9 inhibitors[J]. Chinese Journal of Internal Medicine, 2013, 52(7):27-28.

[11] Meta-analysis of the efficacy and safety of PCSK9 inhibitors in the treatment of familial hypercholesterolemia. DOI: 10.3969/j.issn.1002-266X.2016.46.014.

[12] Outpatient Clinic. Peng Daoquan: The lower the LDL-C level, the lower the risk of ASCVD, and the failure threshold has not yet been found. New Horizons in Outpatient Clinic, 2018.

[13] FOURIER study Asian population analysis released!. Cardiovascular Remote Platform, 2018.