For most patients diagnosed with COVID-19, the majority of symptoms pass after a week or two. However, a group of patients is dealing with aftereffects for weeks, even months--what the healthcare community calls “long COVID.”
The life-sciences industry does not yet understand why some patients get seriously ill from COVID and why others have no symptoms at all, nor what the factors behind long COVID cases are. Nancy Dreyer, epidemiologist and chief scientific officer with IQVIA, spoke with Outsourcing-Pharma about the phenomenon of long COVID, and the resources the research community is turning to in the hopes of gaining wisdom about the condition.
OSP: Can you share a slice of what it’s like to be an epidemiologist during COVID-19’s rampage?
ND: Prior to the COVID-19 pandemic, people often thought that epidemiology referred to skin disease. This pandemic made epidemiology a household name and, in turn, lots of people became “armchair epidemiologists.” Mixed messages about how best to protect ourselves have made it feel like we are also suffering from an epidemic of misinformation.
That said, it is extraordinarily difficult to try to control a pandemic. COVID is my third pandemic, and by far, the one with the biggest toll on human life.
OSP: Could you please talk about how amassing data from various sources has helped further our understanding of COVID-19, and how the disease impacts patients?
ND: Real-world data (RWD) is the first line of defense for natural disasters. When we hear of a potential threat, we start counting and looking for patterns. For COVID, we have used hospital records to understand the characteristics of people who present with serious, life-threatening conditions.
Additionally, we are using RWD from outpatient ambulatory care visits to understand post-acute sequelae of COVID-19, sometimes called PASC or long COVID. Another factor brought to light by the pandemic is the importance of the voice of the patient, both through systematic research programs like our online study of COVID in the community and through grass-root patient organizations – particularly those formed around long COVID, giving it visibility and shaping the character of this emerging condition.
Last, we also see a variety of new data sources that are helping shape our understanding of COVID. For example, in professional sports such as the National Basketball Association (NBA), which has generated important information about disease transmission among people in close quarters, using real-world evidence (RWE) assembled from its “closed campus occupational health program” which ran last year during what we called the “NBA bubble.” They used data from daily lab tests of all participating players, staff, and most vendors, collected before and during campus activities, and were able to study transmission during participation in close contact, unmasked activities.
The National Football League (NFL) also studied their players with regular testing and used the information to adjust their COVID management protocols. Their data showed transmission after less than 15 minutes or close interactions. The scientific evidence from these sports leagues was published in prestigious medical journals, including JAMA Internal Medicine, Annals of Internal Medicine, and CDC’s Morbidity and Mortality Weekly Report, living proof of the value of diverse RWE and how various sources can make important contributions to aspects of interest.
OSP: What exactly is long COVID? What are the most common persistent symptoms patients are still struggling with months out?
ND: The Centers for Disease Control and Prevention (CDC) typically talk about long COVID in terms of symptoms that last more than 4 weeks after being infected with COVID. Symptoms seem to be a combination of exhaustion and severe fatigue often coupled with respiratory problems, brain fog, heart palpitations, joint or muscle pain, and diarrhea.
Additionally, there are multiorgan effects or autoimmune conditions that persist over a longer time with symptoms lasting weeks or months after COVID illness. Multiorgan effects can impact many, if not all, body systems, including heart, lung, kidney, skin, and brain functions.
While long COVID seems to be quite real, we also see some similar symptoms among the uninfected that likely reflect the toll of the pandemic experience on the population. An example is depression that may stem from or be aggravated by prolonged isolation – a condition that is independent of having been infected with COVID.
OSP: You mention that the medical community is struggling to understand why some folks get severe symptoms and some none at all, and why some come out on the other side with no lingering effects, and others have severe, persistent after-effects. Could you please talk about that journey and how progress might be made?
ND: Scientific discovery is a journey that advances through conjecture and refutation. Researchers produce ideas, test them, and, if they find something of interest, investigate whether it is also evident in other populations. General statements about nature come from findings that are not limited to one time and place. Causal mechanisms should be repeatable in different populations, and when you see similar findings in those different populations, it adds credence to the findings.
As with every disease, some people are more vulnerable than others. For COVID, we looked first for quick fixes. For example, there were suggestions that vitamin D would protect people from COVID, as well as anti-ulcer over-the-counter (OTC) medications and daily antihistamine use. None of these hypotheses have panned out so far in our studies, but there may be protective benefits of some of these supplements when used in combination with other factors we have not yet identified.
We are still in the early stages of the search for why some people get sick and why others do not. We found that people with autoimmune disorders are at higher risk of getting very sick from COVID. They are 30% more likely to have severe symptoms during the acute phase of the infection, and more than twice as likely to report persistent, debilitating symptoms of COVID-19, such a shortness of breath and fatigue, than other study participants. Also, people with hypertension report more symptoms and more serious COVID symptoms, even 30 days after having tested positive for COVID.
It is also important to note what we are not seeing. In our community-based work, African Americans have reported substantially fewer symptoms and serious symptoms than white patients. Additionally, diabetics do not appear to have more or worse symptoms than others with COVID, a theory that was once proposed after an early high-profile movie star who was diabetic tested positive for COVID early in the pandemic.
OSP: Could you please talk about how RWD and/or RWE [please feel free to talk about one or both, whichever you feel appropriate] are helping gain insights into COVID? Specifically, how have community-based registries helped?
ND: Most of what we have learned about COVID has come from RWD. This is not intended to diminish the value of randomized controlled trials (RCTs), but apart from rare platform trials like those conducted by the UK National Health Service, it takes a long time to set up a trial, enroll people, conduct and complete the study. And by their very design, they are quite costly.
The CARE project is a voluntary, unpaid online study that has more than 30,000 participants who are contributing information about their experience with COVID and the COVID vaccine. We continue to recruit people who have been tested for COVID, no matter what the results, or who have been vaccinated – so the study is open to just about any adult in the US.
This represents the bulk of adult human experience with COVID in the US since most people are not going to health care facilities for COVID unless they are extremely ill. We are working to leverage these data to understand how to mitigate risk. Example questions we want to be answered include:
- Is there anything that will help us be more resistant to COVID?
- Who is at the highest risk?
- How are most people affected by the vaccine? Does it knock them out for days? Do they miss work? Should they plan to get childcare coverage because they can’t take care of themselves and their families? Does everybody react the same way or are some people more likely to suffer side effects?
OSP: Can you share ways in which IQVIA technologies and efforts have specifically helped further our COVID understanding?
ND: We are leveraging IQVIA technology to collect information directly from the public about COVID. Patient-generated health data (PGHD) needs to be handled differently than traditional data collection from clinicians or health systems. That being said, it is an art to communicate in a way that regular people without medical training can understand and respond to, and to know when clinical validation is needed versus when a patient-reported outcome is sufficient. As we accumulate more information, big data, artificial intelligence, and machine learning will be important tools to look for patterns that may not be immediately noted.