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As COVID-19 continues to take center stage in our lives, with new theories regularly raising new concerns, one thing is clear: There are more questions than answers right now.

Patients with high blood pressure know this all too well as reports about a speculative possible connection between their medication and COVID-19 are causing alarm.

But many experts report the relationship between ACE inhibitors or angiotensin receptor blockers and COVID-19 is unclear and that patients taking these medications shouldn't stop.

One of these experts, Michigan Medicine cardiologist James Brian Byrd, M.D., M.S., is a collaborator in a clinical trial studying the relationship between the virus and ACE inhibitor and ARB medications for hypertension. 

"This is a new illness and there are a lot of unknowns," says Byrd. "We want to get information out there for patients, and that information has to be solid. We need to be cautious so the information is based on studies that have been reviewed by scientists and judged to be of adequate quality to affect decision-making."

In a departure from media coverage in the past, many studies featured in news reports on this topic haven't been checked (or, what experts call "peer reviewed") for quality, Byrd says.  

With this in mind, Byrd answers some important questions here:

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Does taking an ACE inhibitor or ARB increase my risk of contracting COVID-19?

There is currently no solid indication that patients being treated with ACE inhibitors or angiotensin receptor blockers are at higher risk of contracting COVID-19 or of experiencing more severe symptoms related to the virus.

Should I ask my doctor about taking a different medication or stopping altogether?

Currently, there is no good rationale for changing medications — and it could be to your detriment. Stopping your medication or replacing it with another medication can result in a worsening of your condition. We know that ACE inhibitors and ARBs are useful drugs to treat high blood pressure. Stopping these drugs could lead to a decline in control of your condition. If a patient does stop the medication, there needs to be a strong reason for it under the direction of his or her doctor. 

What is the "suspected" connection?

There are animal studies that suggest angiotensin converting enzyme 2 (ACE2), which the virus uses to enter cells, may be increased in certain parts of the body as a result of taking an ACE inhibitor or ARB. No firm conclusions about COVID-19 can be drawn from these studies, which did not involve humans, viral infection or the lungs, the most commonly affected organ impacted by COVID-19. Early reports suggested that people who did worse after contracting COVID-19 often had high blood pressure. However, no firm conclusions can be drawn from that observation since older patients often have high blood pressure and tend to do worse if they acquire COVID-19.

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To conclude that high blood pressure increases the risk of serious COVID illness would require a totally different type of study, which has not been done. Other studies — also not strong enough to change what people should do — have preliminarily suggested that patients taking ACE inhibitors or ARBs may do better when infected with COVID-19.

To summarize, there is no solid evidence that blood pressure medications play a role — favorable or unfavorable — in COVID-19 infection.

What is your advice to patients?

Patients who are prescribed an ACE inhibitor or ARB for high blood pressure should not change their therapy unless advised to do so by their doctor. Not a lot is known about COVID-19 since it's so new and since research takes time, but an enormous number of doctors and researchers are studying this virus. In the meantime, we want patients to follow the guidelines issued by many professional societies: Continue with your medication. We are working hard to figure it out, including involvement in the REPLACE COVID trial.

What is involved in this trial?

The REPLACE COVID trial studies the relationship between ACE inhibitors/ARBs and COVID-19. The trial will recruit hospitalized patients already taking these medications to determine whether discontinuing them affects the severity of COVID-19 symptoms. These hospitalized patients have either tested positive or are under investigation for the virus. In the study, half the patients who wish to participate will continue with their medication and half will stop. We will follow patients after they leave the hospital and analyze the data. The information from this trial will give us a much stronger idea about what should be done.