Individuals with PCOS are 2x more likely to have high cholesterol (also known as dyslipidemia) than those without PCOS.[1]  Dyslipidemia is characterized by abnormally high levels of lipids or fats in the blood and is a significant risk factor for cardiovascular (CV) diseases.[2]

In this article we explore the link between PCOS and dyslipidemia.

PCOS is associated with elevated levels of androgens[3], sex hormones that are produced in the ovaries, start at puberty and play a key role in reproductive health.[4] 

• An Increase in the level of circulating androgens disrupts the way that adipose tissue, the body fat or connective tissue that extends throughout your body,[5] metabolizes glucose;[6]

• The adipose tissue produces less adiponectin, a hormone that helps with insulin sensitivity and inflammation,[7] and more leptin,[8] a hormone that causes you to feel hungry in efforts to maintain enough fat stores for long-term health;[9]

• Reduced adiponectin leads to insulin resistance, whereby the body doesn’t respond as it should to the effects of insulin;[10] 

• Insulin resistance in fat cells stimulates the release of fatty acids into the blood;[11],[12]

• Increased levels of fatty acids in the blood stimulate the liver to produce and secrete very low-density lipoprotein (VLDL);[13]

• The release of VLDL into the blood results in an increased level of lipids in the blood overall, hypertriglyceridemia, and stimulates the exchange of cholesteryl esters (a type of dietary fat that is a derivative of cholesterol)[14] from both high-density lipoprotein (HDL) and low-density lipoprotein (HDL);[15]

• The triglyceride (TG) enriched HDL then releases Apolipoprotein A-1 (ApoA-1) protein into the blood;[16]

• ApoA-1 is cleared rapidly from the blood, partly through excretion via the kidney, leaving HDL less available to play a role in removing cholesterol from the body;[17]

• In parallel the TG enriched HDL undergoes lipolysis (the process through which lipids are broken down to access stored energy)[18] and becomes smaller and more dense;[19] and

• There is a resulting low level of available HDL and high levels of small dense LDL.[20],[21]

  
  

HDL is often known as the “good” cholesterol as it picks up excess cholesterol from the blood, carries it to the liver and then the liver gets rid of the excess cholesterol by breaking it down and excreting it.[22]  LDL is known as the “bad” cholesterol as it the form of cholesterol that can build up within the walls of blood vessels, narrowing them and increasing the risk of a clot getting stuck and causing a stroke or heart attack.[23]

Insulin resistance can lead to additional health complications, including:[24]

• Hyperinsulinemia, elevated production of insulin;

• Hyperglycemia, or high blood sugar;

• High blood pressure or hypertension, where increased retention of sodium in the kidneys alters the renin-angiotensin-aldosterone system (RAAS) leading to increased arterial blood pressure[25] and elevated levels of insulin (through hyperinsulinemia) stimulate the sympathetic nervous system and cause thickening of the smooth muscle layers in arteries;[26] 

• Elevated inflammatory markers, where insulin resistance promotes the accumulation of microphages, small white blood cells, in fat cells which in turn attract, macrophages, white blood cells that stimulate the immune system;[27]

• Endothelial dysfunction, a type of coronary artery disease,[28] where the elevated inflammatory markers increase circulating levels of free fatty acids causing vascular insulin resistance;[29]

• A prothrombotic state, a heightened level of blood coagulation that increases the risk of thrombosis,[30] caused by changes in number and activity of white blood cells;[31] and

• Type 2 diabetes (T2D).

Individuals with high cholesterol may not experience symptoms at first.  As plaque builds up in the arteries, the individual can develop coronary artery disease (CAD) with symptoms including:[32]

• Chest pain with exertion;

• Jaw pain; and

• Shortness of breath.

There are a variety of other causes of dyslipidemia including:[33]

• Genetic pre-disposition to high triglycerides or LDL cholesterol due to a variety of inherited conditions;

• Obesity, especially excess weight around the waist;

• Diabetes;

• Hypothyroidism;

• Alcohol use disorder;

• Metabolic syndrome;

• Excessive consumption of saturated and trans fats;

• Cushing’s syndrome;

• Inflammatory bowel disease (IBD/IBS);

• Severe infections, such as HIV; and

• An abdominal aortic aneurysm.

High cholesterol or dyslipidemia is diagnosed with a blood test known as a lipid panel or lipid profile.[34]  This measures total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides.  For this test, you will likely be asked to avoid consuming food or liquids other that water for 9-12 hours beforehand.

Your doctor will likely recommend lifestyle changes to lower your cholesterol at first, including:[35]

• Reduced intake of saturated fats, found in meat and dairy products;

• Reduced intake of trans sats, found in vegetable oil, margarines and processed foods;

• Increased intake of omega-3 fatty acids, found in oily fish, walnuts and flaxseeds;

• Increased intake of soluble fibre, found in oatmeal, kidney beans and some fruits and vegetables;

• Increased intake of whey protein;

• Increased level of moderate intensity physical activity;

• Quitting smoking;

• Losing weight; and

• Drinking alcohol in moderation.

• If lifestyle changes are not sufficient, medications such as statins, may be prescribed.[36]

Reviewed by Riya Ganguly PhD., MBA, ICD.D, expert on technology transfer, new venture development and research facilitation

Sources

[1] https://pubmed.ncbi.nlm.nih.gov/20807166/

[2] https://www.ncbi.nlm.nih.gov/books/NBK560891/

[3] https://www.uptodate.com/contents/polycystic-ovary-syndrome-pcos-beyond-the-basics/

[4] https://my.clevelandclinic.org/health/articles/22002-androgens

[5] https://my.clevelandclinic.org/health/body/24052-adipose-tissue-body-fat

[6] https://ovarianresearch.biomedcentral.com/articles/10.1186/s13048-022-01091-0

[7] https://my.clevelandclinic.org/health/articles/22439-adiponectin

[8] https://my.clevelandclinic.org/health/articles/22446-leptin

[9] https://ovarianresearch.biomedcentral.com/articles/10.1186/s13048-022-01091-0

[10] https://www.mayoclinic.org/diseases-conditions/type-2-diabetes/expert-answers/hyperinsulinemia/faq-20058488

[11] https://cardiab.biomedcentral.com/articles/10.1186/s12933-018-0762-4

[12] https://www.jci.org/articles/view/10762/figure/1

[13] https://cardiab.biomedcentral.com/articles/10.1186/s12933-018-0762-4

[14] https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/cholesteryl-ester

[15] https://www.jci.org/articles/view/10762/figure/1

[16] https://www.jci.org/articles/view/10762/figure/1

[17] https://pubmed.ncbi.nlm.nih.gov/9519340/

[18] https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/lipolysis

[19] https://www.jci.org/articles/view/10762/figure/1

[20] https://cardiab.biomedcentral.com/articles/10.1186/s12933-018-0762-4

[21] https://www.jci.org/articles/view/10762/figure/1

[22] https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/in-depth/hdl-cholesterol/art-20046388

[23] https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/in-depth/hdl-cholesterol/art-20046388

[24] https://www.ncbi.nlm.nih.gov/books/NBK507839/

[25] https://www.ncbi.nlm.nih.gov/books/NBK470410/

[26] https://journals.lww.com/cardiovascularendocrinology/fulltext/2014/12000/role_of_insulin_resistance_in_essential.4.aspx

[27] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5873875/

[28] https://my.clevelandclinic.org/health/diseases/23230-endothelial-dysfunction

[29] https://www.nature.com/articles/ncpendmet0366

[30] https://bestpractice.bmj.com/topics/en-us/889

[31] https://www.mdpi.com/2077-0383/10/11/2419

[32] https://my.clevelandclinic.org/health/diseases/21656-hyperlipidemia

[33] https://www.medicalnewstoday.com/articles/321844#types-and-causes

[34] https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/diagnosis-treatment/drc-20350806

[35] https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/in-depth/reduce-cholesterol/art-20045935

[36] https://www.heart.org/en/health-topics/cholesterol/prevention-and-treatment-of-high-cholesterol-hyperlipidemia/cholesterol-medications