Are COVID Vaccines Protecting People with Obesity?

To Her Tower She Climbed and Took Her Shield

In a word, yes. COVID vaccines are still protecting people with obesity. Two new studies remind us that, although people with obesity are more vulnerable to this virus, the immune response is still good in this population. This is true of the immune response to infection as well as the protection afforded by vaccination.

A Large UK Cohort

Let’s start by remembering that approval of COVID vaccines by FDA came because of robust data showing that each of the vaccines work well in people at a wide range of BMI. So subsequent research is really confirmatory to tell us if this protection is holding up in real world use.

The most recent study appears in Lancet Diabetes & Endocrinology. It’s a cohort study of 9,171,524 persons in the QResearch database of GP medical records from the UK. Carmen Piernas and colleagues used a nested matched case-control design to estimate the odds for bad outcomes with COVID-19. They had BMI and vaccination data on all of these individuals.

What they found was evidence of good protection from vaccination against severe COVID-19 in people with overweight and obesity. That’s not to say that the protection is absolute. Though the vaccine is protective, the fact remains that people with obesity do have a higher risk to start with if they become infected. Vaccination simply cuts that risk, just as it cuts the risk for anyone else.

T Cell Immunity

The other recent study worth noting is a study that digs a little deeper into the immune response to SARS-CoV-2. Most studies that generate a lot of headlines only look at antibodies. But the immune response involves much more than just producing antibodies. In Obesity, Neil Wrigley Kelly and colleagues report on the durability of T cell immunity in people with obesity and matched controls. Such studies are more complex than the simpler and more common antibody studies. But they are important for fully understanding the immune response to a viral infection like COVID.

What they found was a robust and durable T cell immune response in people with obesity who survived infection with SARS-CoV-2. This is important because T cell immune response plays a key role in protecting us from repeated viral infections. Note that this was a study of people who became infected before the vaccines were available. So it’s telling us that people with obesity can indeed mount an immune response to COVID (if they survive it) that protects them from repeat infections just as well as anyone else.

COVID Is Still With Us

It would be nice to stop worrying about COVID altogether. But that’s not where we are right now. A new variant of Omicron, BA.5, is spreading in the U.S. and sparking a new bump in COVID cases. We don’t know that it will be any more severe than waves of prior variants and we certainly don’t know how big it will be.

But we do know this. It’s still smart to be careful. And being careful includes being fully vaccinated because the COVID vaccines can protect us all, regardless of obesity.

Click here for the Piernas study, here for the Kelly study, and here for further perspective. For more on the BA.5 variant, click here and here.

To Her Tower She Climbed and Took Her Shield, illustration by Eleanor Fortescue-Brickdale / WikiArt

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July 8, 2022