Fight Obesity Now or be a Prey to Falling COVID Immunity

People with severe obesity are more likely to experience hospitalization or death from COVID-19 despite vaccination, according to researchers from the Universities of Cambridge and Edinburgh. According to the findings, those who are obese are more likely to require more regular booster doses to maintain their immunity (1^✔ ✔Trusted Source
Accelerated waning of the humoral response to COVID-19 vaccines in obesity

Go to source). Clinical trials have demonstrated that COVID-19 vaccines are highly effective at lowering virus-related symptoms, hospitalization, and mortality, including in obese patients.

Previous research has revealed that antibody levels in vaccinated people with obesity may be lower, putting them at a higher risk of severe disease than vaccinated people of normal weight.

However, the reasons for this have remained unknown.

Those Extra Kilos Might be Costing you Your Immunity

The current study, published in the journal Nature Medicine Today, indicates that the effectiveness of antibodies to deactivate the virus falls faster in obese, vaccinated patients. The findings have far-reaching consequences for vaccine-prioritizing programs worldwide.

Obese people were more likely to be hospitalized, require ventilators, and die from COVID-19 during the epidemic. The researchers set out to assess how far two of the most widely used vaccines protect people with obesity over time compared to those with a normal weight.

As part of the EAVE II project, a team from the University of Edinburgh led by Prof. Sir Aziz Sheikh examined real-time data tracking the health of 3.5 million people in the Scottish population.

They studied COVID-19 hospitalization and death in people who got two doses of COVID-19 vaccination (Pfizer-BioNTech BNT162b2 mRNA or AstraZeneca ChAdOx1).

The Higher your BMI, the more Infections Enter your Body

They discovered that patients with extreme obesity (BMI greater than 40 kg/m2) had a 76% higher chance of severe COVID-19 outcomes than people with a normal BMI.

Advertisement

People with obesity (30–39.9 kg/m2), which affects a quarter of the UK population, and those who were underweight also had a little increase in risk. 'Break-through infections' after the second vaccine dosage necessitated hospitalization as well.

"Our findings show that protection gained through COVID-19 vaccination drops off faster in people with severe obesity than in people with a normal body mass index," stated Prof. Sir AzizSheikh.

Advertisement

“Using large-scale data assets such as Scotland's EAVE II Platform, we were able to provide crucial and timely insights that will allow us to improve the delivery of COVID-19 vaccine regimens in the post-pandemic UK."

The team from the University of Cambridge, led by Dr. James Thaventhiran of the MRC Toxicology Unit and Prof. Sadaf Farooqi of the Wellcome-MRC Institute of Metabolic Science, studied people with severe obesity at Addenbrooke's Hospital in Cambridge and compared the number and function of immune cells in their blood to those of people of normal weight.

They followed up with participants six months after their second vaccine dosage to see how they responded to a third "booster" vaccine dose over time.

The Cambridge researchers discovered that six months after receiving a second dose of the vaccination, those with severe obesity had comparable levels of antibodies to the COVID-19 virus as those of normal weight.

However, the ability of such antibodies to fight the virus efficiently (known as "neutralization capacity”) was lower in obese adults (2^✔ ✔Trusted Source
The majority of SARS-CoV-2-specific antibodies in COVID-19 patients with obesity are autoimmune and not neutralizing

Go to source).

In comparison to adults with normal BMI, 55% of those with severe obesity had an unquantifiable or undetectable “neutralizing capacity”.

"This study further emphasizes that obesity alters the vaccine response and also impacts the risk of infection," said Dr. Agatha van der Klaauw from the Wellcome-MRC Institute of Metabolic Science and the first author of the paper. "We urgently need to understand how to restore immune function and minimize these health risks."

The researchers discovered that antibodies produced by patients with significant obesity were less effective at neutralizing the SARS-CoV-2 virus, possibly because the antibodies were not as strong at binding to the virus.

When both the normal-weight and severely obese groups received a third (booster) dose of a COVID-19 vaccination, the ability of the antibodies to deactivate the virus was restored.

However, the researchers discovered that immunity deteriorated more rapidly in patients with significant obesity, putting them at a higher risk of infection over time.

Dr. James Thaventhiran, Group Leader of the MRC Toxicology Unit in Cambridge and co-author of the SCORPIO study, stated: "It is promising to see that booster vaccines restore the effectiveness of antibodies for people with severe obesity, but it is concerning that their levels decrease more quickly, after just 15 weeks.

This shows that the vaccines work as well in people with obesity, but the protection doesn’t last as long."

"More frequent booster doses are likely to be required to maintain protection against COVID-19 in people with obesity," stated Prof. Sadaf Farooqi of the Wellcome-MRC Institute of Metabolic Science and co-lead author of the SCORPIO study. Because of the global prevalence of obesity, this poses a significant issue for health care."

References:

1. Accelerated waning of the humoral response to COVID-19 vaccines in obesity - (https://www.nature.com/articles/s41591-023-02343-2)
2. The majority of SARS-CoV-2-specific antibodies in COVID-19 patients with obesity are autoimmune and not neutralizing - (https://pubmed.ncbi.nlm.nih.gov/34744161/)

Source-Medindia