According to a recent study sponsored by the Icahn School of Medicine at Mount Sinai and Yale School of Medicine published in Nature, patients with long COVID-19 exhibit definite immunological and hormonal function differences from those without the illness.
When patients from the Mount Sinai Health System reported ongoing problems following a COVID-19 diagnosis in 2020, doctors from the Mount Sinai Health System were the first to identify long-term COVID symptoms. The "brain fog," fatigue, shortness of breath, and chronic discomfort were among these symptoms.
According to the Centers for Disease Control and Prevention, 7.5% of adults in the United States experience long COVID symptoms, which are symptoms that remain for more than three months afterward.
These discoveries are critical, according to principal investigator David Putrino, because they may help develop more accurate tests for people with long COVID and individualized treatments for long COVID that still need to be supported by scientific evidence.
This study further proves why these symptoms may exist in patients who frequently lack a known explanation for their illness.
"This work is so exciting because it is one of the first to show us clear, measurable differences in blood biomarkers of people with long COVID compared with people who recovered fully from an acute infection and a group of people who have never been infected with SARS-CoV-2 (the virus that causes COVID-19). This is a decisive step forward in the development of valid and reliable blood testing protocols for long COVID."- Putrino
How did the scientists examine long COVID differences?
Between January 2021 and June 2022, researchers examined 271 patients from three locations: The Mount Sinai Hospital, Mount Sinai Union Square, and Yale School of Medicine.
They were split into three groups by researchers: individuals without a history of SARS-CoV-2 infection, those who had recovered from a case of COVID-19 as determined by clinical examination, and those who had long-lasting COVID symptoms that persisted for at least four months after the diagnosis of COVID-19 infection.
Every individual was required to complete a thorough series of questions regarding their symptoms, medical background, and quality of life about their health. Blood samples were collected from all patients, and the researchers then used machine learning techniques to understand further which biomarkers were most helpful in enabling the system to identify patients with long COVID.
In summary, based on distinguishing traits found in participants' blood in the long COVID group, the algorithm could diagnose the condition and distinguish between those with and without long COVID with 96% accuracy.
Immune and hormonal dysfunction were some of the most notable long covid differences.
Biomarkers showing aberrant T-cell activity, the reactivation of numerous latent viruses, such as the Epstein-Barr virus and other herpesviruses, and much lower cortisol levels were associated with this.
"These findings show us that people with long COVID are living with a disease process that is observable using the blood testing protocols laid out in the study, but also varies from patient to patient depending on their specific medical history."- Putrino
According to principal investigator Akiko Iwasaki, the team is thrilled to discover such distinct changes in the immunological phenotypes between individuals with and without long COVID. These markers offer a starting point for analyzing the illness etiology of long COVID but need to be verified in more extensive research.