The Surprising Impact of COVID-19 on Stroke Risk and Brain Health

February 16, 2024

Four years after the onset of the COVID-19 pandemic, researchers have gained significant insights into the link between the coronavirus and other serious health problems.  With cases of a new COVID variant recently on the rise, it’s vital that we understand how this disease poses threats which can endure long after the obvious symptoms have waned.  During this American Heart Month, we’re going to assess the danger posed by COVID-19 to cardiovascular health, and how it can increase your risk of experiencing a stroke.  Most importantly, we’ll describe what you can do about it. 

The Silent, Dangerous Effects of COVID-19  

It’s a mistake to believe that COVID-19 poses no more danger to our health than a nasty dose of the flu.  By now, we’re all familiar with the principal symptoms – coughing, fever, body aches, a shortness of breath – and perhaps the other effects, which can include nausea, diarrhea, and the loss of our sense of smell (known as anosmia), or taste.  

But these are only the visible, short-term impacts of COVID-19, those that might necessitate a few days off work or a canceled vacation.  Unfortunately, research is beginning to show that this disease has much more serious and long-term implications.  

The issue is that SARS-CoV-2, the virus which causes COVID-19, can result in some damaging secondary effects.  The virus initially infects cells in our mucus membranes (located in the nose, mouth, and eyes) by binding with the ACE-2 receptor.  Our lungs are in particular danger because they contain many of these receptors, and there’s a direct path for viral cells to enter the lungs through our airways.  As the virus takes over healthy cells, our immune response kicks in.  This causes inflammation of the lungs and airways, resulting in a buildup of the fluids that cause us to cough.1  Through this simple cause-and-effect mechanism, the virus exports itself into the world every time we cough, endangering those around us.  

In more serious COVID-19 cases, inflammation and fluid buildup affect our alveoli, the thousands of tiny air sacs located deep within the lungs.  These sacs are vital for the process of purging CO2 and bringing in fresh oxygen, an exchange on which all mammals depend for their survival.  

Clogged with fluids, the alveoli become less efficient, dangerously reducing our blood oxygen levels.  Deprived of oxygen, heart muscles become less active, compromising their main task of pumping oxygenated blood around the body.  Our inflammatory response can also disrupt the heart’s subtle electrical signaling, increasing the risk of an irregular heartbeat (known as arrhythmia), or worsening an existing arrhythmia.2  

Furthermore, our immune system dispatches white blood cells to tackle the disease, but a buildup of these sticky cells can lead to the formation of dangerous blood clots.3  Similarly, when a COVID-19 infection reaches our artery walls, it can cause inflammation, especially along the build-up of cholesterol, fats, and cells known as atherosclerotic plaques.4  If inflamed, these plaques further disrupt blood flow through the arteries, leading to health issues which range from angina (chest pain), stroke, erectile dysfunction, and heart attack.5  Studies have shown that COVID-19 sufferers face a 300-800% increase in their heart attack risk during the first week of their illness and experience an increased risk of developing a range of cardiovascular disorders.6, 7, 8

The brain also faces risks from the heightened immune system response and its resulting inflammation.  Long COVID sufferers report a range of neurological problems including insomnia, loss of memory, poor concentration, depression and anxiety (click the last two links for more on long COVID).9 

COVID-19 and the Risk of Stroke 

An ischemic stroke happens when brain arteries are blocked by blood clots or other debris.  We now understand that COVID-19 attacks the lining of blood vessels (which are also replete with ACE-2 receptors), causing the creation of blood clots which initially help to repair the damage.  However, these clots don’t always dissolve when their job is completed, and they can be swept away in the bloodstream to other areas of the body, where they can obstruct blood flow.  Research has confirmed a dramatically increased risk of stroke following a COVID-19 infection.10 

In the brain, blood clots can cause blockages which result in mini strokes (also known as transient ischemic attacks or TIA).  These destroy or damage nerve cells, sometimes causing cell death and prompting a major medical emergency.11,12  The majority of stroke incidences among COVID-19 patients are caused by obstruction to the large blood vessels, apparently a result of increased coagulation in the blood.13, 14  To imagine this, think of a large-diameter garden hose which has a big pebble trapped inside, disrupting the water flow.  Then, replace the water in the hose with maple syrup, and you’ll see the implications of increased blood thickness (known as viscosity), which is also brought about by COVID-19.  

Surprisingly, ischemic stroke can affect asymptomatic sufferers; some patients had no idea they’d had COVID-19 until they found themselves in hospital recovering from a stroke.  There are long-term implications, too.  In one study, a year after a COVID-19 infection, a patient’s risk of stroke is elevated by an alarming 52%.15 

Disruptions in blood flow within the brain can also lead to vascular dementia, which is the second most common neurodegenerative disorder after Alzheimer’s Disease (we will write more on vascular dementia soon). 

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Who is at a Higher Risk of Stroke with COVID-19? 

Researchers compared three groups: 1) COVID-19 patients who suffered a stroke; 2) those who did not, and 3) stroke patients who did not have COVID-19. The ‘COVID/stroke’ group exhibited risk factors which break down roughly as follows: 

Age:  Stroke sufferers were almost twice as likely to be aged 35-54.16  Almost two-thirds of strokes in non-COVID patients occur after the age of 70.  So, COVID-19 patients likely experienced a stroke much earlier in their lives than they otherwise would.17 

Race:  Almost 45% of COVID-positive stroke group were people who are black, while non-COVID stroke patients were less than 20% people who are black.  Almost commensurately, the preponderance of people who are white among the ‘COVID/stroke’ group was 20% lower.  

Racial disparities in diet, lifestyle and obesity are well understood.18, 19, 20, 21  This finding appears to confirm the importance of those underlying factors.  For instance, obesity (i.e., a BMI over 30) was found 16% more commonly in the COVID/stroke group.22 

Diabetes, hypertension (high blood pressure), and hyperlipidemia (elevated levels of cholesterol and triglycerides) were all found in the Covid/stroke group at a higher rate, and are also all factors associated with metabolic syndrome.23  

An irregular heart rhythm (known as atrial fibrillation or arrhythmia), which can cause blood clots in the heart and increases the risk of stroke and heart failure, was also associated with stroke risk among COVID-19 patients.24  Heart conditions such as coronary artery disease and congestive heart failure were also strongly linked to COVID-related stroke risk.25 

Seeing the Signs: How to Know When a Stroke is Happening   

The best medical advice is also easily memorable: ‘Think FAST’: 

FAST 

In the moments after a stroke, sufferers exhibit a sudden facial numbness or weakness in their arms or legs.  They’ll appear confused and have trouble speaking and/or understanding speech.  Vision problems might become apparent in one eye or both, and they’ll appear dizzy and have trouble balancing or coordinating their body.  They might also complain of a severe headache.26 

What You Can Do About It:  Reducing Your Risk of Stroke 

Simple steps can meaningfully reduce your risk of stroke, whether or not you’ve had COVID-19. 

Heart Health:  We’ve seen how heart conditions, especially those that result in blood clots, can cause a stroke.  Make sure to have your heart checked and to follow medical advice on medications and lifestyle changes.   

Regular Exercise:  This one is obvious and associated with a lower stroke risk.27 

Stop Smoking:  Cigarettes damage your body in similar ways to COVID-19.  The blood flow of a smoker has greater ‘stickiness’, causing blood clots.  Smoking also damages cells lining the arteries and causes increased plaque in blood vessels.28  As one study aptly put it, ‘The more you smoke, the more you stroke’.29

Good Dietary Choices:  The Standard American Diet (abundant in saturated fat, excess carbohydrates, and processed foods) is associated with an increased risk of stroke, and conversely, dietary changes can reduce stroke risk by a staggering 80%.30   Long-term studies have shown that adhering to a Mediterranean Diet reduces stroke risk.31, 32, 33

Those recovering from a stroke often become deficient in important nutrients, notably: 

  • Folate (Vitamin B9) - which is important for red blood cell formation. 
  • Vitamin B12 – also important for red blood cells, as well as nerve cell function. 
  • Omega-3 oils (EPA and DHA) – crucial for cell membranes and cardiovascular health. 
  • Vitamin C – an antioxidant which strengthens immune response, among other functions. 
  • Vitamin E – an antioxidant with roles in immune function and cell signaling. 
  • Selenium – important for the thyroid and immune systems. 
  • COQ10 – plays a role in energy regulation and protection against disease. 
  • Choline – important for the function of several organs, including the liver. 
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Research has shown that adherence to the MIND (Mediterranean-DASH Intervention for Neurodegenerative Delay) diet also slows cognitive decline in stroke sufferers.34 

The Bottom Line: Prevention Through Awareness 

Acting early and using the best medical, lifestyle, and nutritional information can empower all of us – COVID-19 sufferers and others – to reduce our risk of ischemic stroke.  The MIND diet, in particular, is a win-win for risk reduction, disease prevention and recovery from stroke.  

But sometimes we fall short of our good intentions and don’t eat these healthy foods consistently.  Filling in the gaps with nutritional supplementation can help to ensure your body is protected from stroke, heart attack and neurodegenerative disorders.  RELEVATE has 17 crucial nutrients from the Mediterranean Diet which are clinically researched for their neuroprotective properties, bioavailable, and include the forms/dosages to support brain health and beyond.  Learn more and shop RELEVATE here.  

And this month, we’re offering a bar of premier dark chocolate and a reusable branded errand bag with each order of the brain healthy nutrition starter pack, which already included 2 bottles of RELEVATE, plus the Brain Health Kitchen Cookbook, to help you embrace the principles of the MIND diet in your everyday routine.  Order by visiting here.

References

  1. Su, Wen-Lin et al. “COVID-19 and the lungs: A review.” Journal of infection and public health vol. 14,11 (2021): 1708-1714. doi:10.1016/j.jiph.2021.09.024 
  2. COVID-19 and the Lungs | NHLBI, NIH. (n.d.). Retrieved February 15, 2024, from https://www.nhlbi.nih.gov/covid/lungs 
  3. Zuo, Yu et al. “Neutrophil extracellular traps in COVID-19.” JCI insight vol. 5,11 e138999. 4 Jun. 2020, doi:10.1172/jci.insight.138999 
  4. How SARS-CoV-2 contributes to heart attacks and strokes | National Institutes of Health (NIH). (n.d.). Retrieved February 15, 2024, from https://www.nih.gov/news-events/nih-research-matters/how-sars-cov-2-contributes-heart-attacks-strokes 
  5. Atherosclerosis - What Is Atherosclerosis? | NHLBI, NIH. (n.d.). Retrieved February 15, 2024, from https://www.nhlbi.nih.gov/health/atherosclerosis 
  6. COVID-19 diagnosis raises risk of heart attack, stroke - Harvard Health. (n.d.). Retrieved February 15, 2024, from https://www.health.harvard.edu/heart-health/covid-19-diagnosis-raises-risk-of-heart-attack-stroke 
  7. Xie, Y., Xu, E., Bowe, B., & Al-Aly, Z. (2022). Long-term cardiovascular outcomes of COVID-19. Nature Medicine 2022 28:3, 28(3), 583–590. https://doi.org/10.1038/s41591-022-01689-3 
  8. Katsoularis, I., Fonseca-Rodríguez, O., Farrington, P., Lindmark, K., & Fors Connolly, A. M. (2021). Risk of acute myocardial infarction and ischaemic stroke following COVID-19 in Sweden: a self-controlled case series and matched cohort study. The Lancet, 398(10300), 599–607. https://doi.org/10.1016/S0140-6736(21)00896-5 
  9. Lopez-Leon, Sandra et al. “More than 50 Long-term effects of COVID-19: a systematic review and meta-analysis.” medRxiv : the preprint server for health sciences 2021.01.27.21250617. 30 Jan. 2021, doi:10.1101/2021.01.27.21250617. Preprint. 
  10. Tu, T. M., Seet, C. Y. H., Koh, J. S., Tham, C. H., Chiew, H. J., de Leon, J. A., Chua, C. Y. K., Hui, A. C. F., Tan, S. S. Y., Vasoo, S. S., Tan, B. Y. Q., Umapathi, N. T., Tambyah, P. A., & Yeo, L. L. L. (2021). Acute Ischemic Stroke During the Convalescent Phase of Asymptomatic COVID-2019 Infection in Men. JAMA Network Open, 4(4), e217498–e217498. https://doi.org/10.1001/JAMANETWORKOPEN.2021.7498 
  11. Study identifies autoimmune antibodies as culprit behind life-threatening blood clots in COVID-19 | NHLBI, NIH. (n.d.). Retrieved February 15, 2024, from https://www.nhlbi.nih.gov/news/2020/study-identifies-autoimmune-antibodies-culprit-behind-life-threatening-blood-clots-covid 
  12. Stroke - Symptoms and causes - Mayo Clinic. (n.d.). Retrieved February 15, 2024, from https://www.mayoclinic.org/diseases-conditions/stroke/symptoms-causes/syc-20350113 
  13. Bigliardi, Guido et al. “Middle cerebral artery ischemic stroke and COVID-19: a case report.” Journal of neurovirology vol. 26,6 (2020): 967-969. doi:10.1007/s13365-020-00898-1 
  14. Kim, Y., Parekh, M. A., Li, X., Huang, Y., Zhang, G.-Q., & Manwani, B. (2023). Age and sex-specific stroke epidemiology in COVID-19. Frontiers in Stroke, 2, 1172854. https://doi.org/10.3389/FSTRO.2023.1172854 
  15. Sidik, S. M. (2022). Heart-disease risk soars after COVID - even with a mild case. Nature, 602(7898), 560. https://doi.org/10.1038/D41586-022-00403-0 
  16. Qureshi, A. I., Baskett, W. I., Huang, W., Shyu, D., Myers, D., Raju, M., Lobanova, I., Suri, M. F. K., Naqvi, S. H., French, B. R., Siddiq, F., Gomez, C. R., & Shyu, C. R. (2021). Acute Ischemic Stroke and COVID-19. Stroke, 52(3), 905–912. https://doi.org/10.1161/STROKEAHA.120.031786 
  17. Fifi, J. T., & Mocco, J. (2020). COVID-19 related stroke in young individuals. The Lancet Neurology, 19(9), 713–715. https://doi.org/10.1016/S1474-4422(20)30272-6 
  18. Satia, Jessie A. “Diet-related disparities: understanding the problem and accelerating solutions.” Journal of the American Dietetic Association vol. 109,4 (2009): 610-5. doi:10.1016/j.jada.2008.12.019 
  19. Li, W et al. “Racial Differences in Eating Patterns and Food Purchasing Behaviors among Urban Older Women.” The journal of nutrition, health & aging vol. 21,10 (2017): 1190-1199. doi:10.1007/s12603-016-0834-7 
  20. National Academies of Sciences, E. and M., Division, H. and M., Practice, B. on P. H. and P. H., States, C. on C.-B. S. to P. H. E. in the U., Baciu, A., Negussie, Y., Geller, A., & Weinstein, J. N. (2017). The State of Health Disparities in the United States. Communities in Action: Pathways to Health Equity, 1–558. https://doi.org/10.17226/24624 
  21. Byrd, A. S., Toth, A. T., & Stanford, F. C. (2018). Racial Disparities in Obesity Treatment. Current Obesity Reports, 7(2), 130. https://doi.org/10.1007/S13679-018-0301-3 
  22. Belani, P., Schefflein, J., Kihira, S., Rigney, B., Delman, B. N., Mahmoudi, K., Mocco, J., Majidi, S., Yeckley, J., Aggarwal, A., Lefton, D., & Doshi, A. H. (2020). COVID-19 Is an Independent Risk Factor for Acute Ischemic Stroke. AJNR: American Journal of Neuroradiology, 41(8), 1361. https://doi.org/10.3174/AJNR.A6650 
  23. Qureshi, A. I., Baskett, W. I., Huang, W., Shyu, D., Myers, D., Raju, M., Lobanova, I., Suri, M. F. K., Naqvi, S. H., French, B. R., Siddiq, F., Gomez, C. R., & Shyu, C. R. (2021). Acute Ischemic Stroke and COVID-19. Stroke, 52(3), 905–912. https://doi.org/10.1161/STROKEAHA.120.031786 
  24. Atrial Fibrillation | cdc.gov. (n.d.). Retrieved February 15, 2024, from https://www.cdc.gov/heartdisease/atrial_fibrillation.htm 
  25. Belani, P., Schefflein, J., Kihira, S., Rigney, B., Delman, B. N., Mahmoudi, K., Mocco, J., Majidi, S., Yeckley, J., Aggarwal, A., Lefton, D., & Doshi, A. H. (2020). COVID-19 Is an Independent Risk Factor for Acute Ischemic Stroke. AJNR: American Journal of Neuroradiology, 41(8), 1361. https://doi.org/10.3174/AJNR.A6650 
  26. Stroke - Symptoms | NHLBI, NIH. (n.d.). Retrieved February 15, 2024, from https://www.nhlbi.nih.gov/health/stroke/symptoms 
  27. Gallanagh, Siobhan et al. “Physical activity in the prevention and treatment of stroke.” ISRN neurology vol. 2011 (2011): 953818. doi:10.5402/2011/953818 
  28. Smoking and Heart Disease, Stroke, and Peripheral Artery Disease | Overviews of Diseases/Conditions | Tips From Former Smokers | CDC. (n.d.). Retrieved February 15, 2024, from https://www.cdc.gov/tobacco/campaign/tips/diseases/heart-disease-stroke.html 
  29. Shah, R. S., & Cole, J. W. (2010). Smoking and stroke: the more you smoke the more you stroke. Expert Review of Cardiovascular Therapy, 8(7), 917. https://doi.org/10.1586/ERC.10.56 
  30. Spence, J David. “Nutrition and Risk of Stroke.” Nutrients vol. 11,3 647. 17 Mar. 2019, doi:10.3390/nu11030647 
  31. Paterson, K. E., Myint, P. K., Jennings, A., Bain, L. K. M., Lentjes, M. A. H., Khaw, K. T., & Welch, A. A. (2018). Mediterranean Diet Reduces Risk of Incident Stroke in a Population With Varying Cardiovascular Disease Risk Profiles. Stroke, 49(10), 2415–2420. https://doi.org/10.1161/STROKEAHA.117.020258 
  32. Lakkur, Sindhu, and Suzanne E Judd. “Diet and Stroke: Recent Evidence Supporting a Mediterranean-Style Diet and Food in the Primary Prevention of Stroke.” Stroke vol. 46,7 (2015): 2007-11. doi:10.1161/STROKEAHA.114.006306 
  33. Paterson, Katherine E et al. “Mediterranean Diet Reduces Risk of Incident Stroke in a Population With Varying Cardiovascular Disease Risk Profiles.” Stroke vol. 49,10 (2018): 2415-2420. doi:10.1161/STROKEAHA.117.020258 
  34. Cherian, L., Wang, Y., Fakuda, K., Leurgans, S., Aggarwal, N., & Morris, M. (2019). Mediterranean-Dash Intervention for Neurodegenerative Delay (MIND) Diet Slows Cognitive Decline After Stroke. The Journal of Prevention of Alzheimer’s Disease, 6(4), 267–273. https://doi.org/10.14283/JPAD.2019.28/METRICS 
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