- Researchers looked at the link between blood protein levels and long-term COVID incidence.
- They found that levels of certain blood proteins six weeks after contracting SARS-CoV-2 can predict long-term COVID risk.
- They noted that larger studies are needed to confirm their findings.
Another study suggests that up to
Understanding how long COVID develops could help researchers and clinicians reduce the risk of developing the disease and treat it more effectively.
Recently, researchers published their findings comparing blood samples from healthcare workers who had contracted SARS-CoV-2 and healthcare workers who had not.
They found that blood protein levels within six weeks of contracting SARS-CoV-2 could predict a long incidence of COVID.
“These changes in the blood that we see soon after infection indicate how the person’s immune system has dealt with the infection and may indicate a predisposition to developing persistent symptoms,” said Dr. Wendy Heywood, associate of principal research at University College London (UCL) Biological Mass. Spectrometry Center (BMSC), one of the study’s lead authors, said Medical News Today.
The study, conducted by researchers at University College London, was published in
For the study, the researchers recruited 54 healthcare workers who had a PCR or antibody-confirmed diagnosis of COVID-19, alongside 102 healthcare workers who did not have COVID-19.
All participants were recruited at the start of the pandemic in March 2020, and all COVID-19 cases were classified as “not severe”.
Participants underwent weekly assessments via questionnaires and blood draws for up to 16 weeks. They then completed symptom questionnaires 6 and 12 months after the start of the study.
After analyzing the data, the researchers found that those who tested positive for SARS-CoV-2 had increased levels of 12 proteins involved in oxidative stress, metabolic reprogramming and cell adhesion – which facilitate cellular interaction – compared to those who tested negative.
They further found that as protein levels increased, the more they correlated with the severity of symptoms.
The researchers also noted that abnormal levels of 20 proteins predicted the incidence of long COVID. Several of these proteins had anticoagulant and anti-inflammatory effects.
Other predictor proteins included those involved in red blood cell production and increased iron levels – previously linked to increased tissue damage due to oxidative stress and impaired immunity.
The researchers concluded that non-severe SARS-CoV-2 disrupts proteins in the blood and that blood protein levels may be able to predict long-term COVID risk.
When asked how protein levels and long COVID might be linked, Dr. Dana Hawkinson, medical director of the infection control and prevention program at the University of Kansas Medical Center, who did not participate under consideration, said DTM:
“It still remains very unclear what influence, if any, protein levels have. We believe that one of the main theories of long COVID has to do with persistent inflammation/inflammatory state, as mentioned in the discussion of the authors.
“Some of these identified proteins certainly reflect an inflammatory state. This, in turn, could influence the symptoms of long COVID. [However]these proteins [may also be the] result of this inflammatory state, and not necessarily the cause.
—Dr. Dana Hawkinson
Dr. Jimmy Johannes, a pulmonologist and critical care medicine specialist at MemorialCare Long Beach Medical Center in Long Beach, Calif., who was not involved in the study, also said DTM:
“While there is still a lot we don’t know about the long COVID, it is suspected that some of the symptoms may be related to small blood clots or dysregulation of inflammation.”
Asked about the limitations of the study, Dr. Heywood pointed to a limited number of samples and cases early in the pandemic.
“This study was carried out with samples from one centre. Further studies from other cohorts of centers should be conducted to confirm the results. Also, these samples were collected in the first wave before the vaccine was available, which is useful to give us some insight. [into] how long COVID can develop in unexposed people, but now, as most people are vaccinated or have had COVID-19 infection, we need to see if these changes still occur,” she said. declared.
Dr. Peter Robinson, professor of computational biology at Jackson Laboratory in Farmington, CT, who was not involved in the study, said DTM:
“It’s an interesting study, but its numbers are very small, there’s a lack of proper independent validation, and the results aren’t compared with [protein levels] other types of infection – which one would like to assess which is specific to COVID-19.
“One of the problems in the field is that there are many relatively small studies that lack the statistical rigor to be considered definitive and do not answer the question of what is really going on pathophysiologically. “, did he declare.
“I don’t want to be overly critical of this paper, it’s an interesting observation that will hopefully lead to more research, but I won’t overstate its importance,” he said. he explains.
Dr Heywood said it was too early to talk about immediate applications.
“We can’t improve something until we can measure a biomarker as an outcome. Laboratory changes in biomarkers may be more reliable indicators of response to treatment than asking how a patient is feeling. This will be important for monitoring the success of any new therapeutic trials,” she said.
“[B]Being able to identify people predisposed to developing long-lasting COVID early on could help us test new interventional treatments on the right people.
— Dr. Wendy Heywood
Dr Johannes said while these findings are unlikely to immediately affect the management of long COVID, if replicated and validated in a larger study, they could lead to a test that can predict who is most susceptible. to develop a long COVID.
Dr. Hawkinson added that the findings could one day be used to inform clinicians to prescribe medications, such as antiviral or anti-inflammatory agents, differently or sooner after COVID-19 diagnosis.
“For example, perhaps the early use of Paxlovid, even in young vaccinated patients, can reduce the risk of these persistent symptoms, even though we have substantial data to support the fact that young vaccinated patients do not benefit of the significant benefit of reduced risk of hospitalization that older patients have when using Paxlovid,” he said.