According to a massive controlled study published in Nature (more readable summary here). It also looks like they are saying that this is for non-hospitalized covid patients, though the paper is confusing to me.
I am also a bit confused by what this study is trying to show. In Figure 3 it shows that a lot of things occur more frequently in patients who tested positive for COVID than in their matched controls, more in those hospitalized than that, and yet more in those admitted to the ICU. Per their methods section, this was measured by comparing the number of patients first reporting that condition within the 6 month period following a COVID-19 diagnosis vs the 6 months following (not sure) for everyone else in the VA system.
Looking at their data, they observe that people with a positive COVID-19 test are 1.17x, 2.34x, and 3.44x more likely for non-hospitalized, hospitalized non-ICU, and ICU-admitted patients respectively, to report obesity in the 6 month period than the COVID-19 negative controls. They cite this as an excess burden of obesity of 3.37, 26.15, 46.9 people per thousand among those three groups, which gives a baseline risk of about 1.95% for the control group reporting obesity within their 6 month period, if I’m doing my math right.
So taken at face value, the average person in the VA system has about a 2% per 6 months chance of becoming obese, while the average person admitted to the ICU has about a 7% chance of becoming obese in the next 6 months. I can come up with two possible explanations for that:
People who are admitted to the ICU gain about 3.37x more weight, on average, than people who do not get COVID-19, and as such are about 3.37x more likely to become obese.
Getting COVID-19 has very little effect on your weight, but within the group of people who are not obese, the people who are closer to the threshold of obesity are more likely to be admitted to the ICU for COVID-19.
I don’t have hard evidence one way or the other, but I did some searching for evidence that COVID-19 causes weight gain, and while I found a large number of articles talking about how people are gaining weight under lockdown, I didn’t find any discussing weight gain from COVID-19 directly. Additionally, my prior is that controlling for confounding factors is really really hard, and so even for a study published in Nature I would not be surprised if the authors failed to perfectly control for those confounding factors.
I’d be interested to see what you get if you
Look at weight changes in a group of people who tested positive vs negative for COVID-19 in a specific narrow period, to see if the COVID-positive people experienced more weight gain over that period, controlling for weight at the start of that period (and if so, whether that weight gain was correlated with disease severity).
Reproduce this study, except look the relative risk of experiencing one of these negative sequelae in the 6 month period before a positive COVID-19 diagnosis (if this method successfully controls for confounding factors, doing this should show a hazard ratio very close to 1 for all conditions, assuming that getting COVID can’t cause you to experience negative health outcomes in the past).
I am also a bit confused by what this study is trying to show. In Figure 3 it shows that a lot of things occur more frequently in patients who tested positive for COVID than in their matched controls, more in those hospitalized than that, and yet more in those admitted to the ICU. Per their methods section, this was measured by comparing the number of patients first reporting that condition within the 6 month period following a COVID-19 diagnosis vs the 6 months following (not sure) for everyone else in the VA system.
Looking at their data, they observe that people with a positive COVID-19 test are 1.17x, 2.34x, and 3.44x more likely for non-hospitalized, hospitalized non-ICU, and ICU-admitted patients respectively, to report obesity in the 6 month period than the COVID-19 negative controls. They cite this as an excess burden of obesity of 3.37, 26.15, 46.9 people per thousand among those three groups, which gives a baseline risk of about 1.95% for the control group reporting obesity within their 6 month period, if I’m doing my math right.
So taken at face value, the average person in the VA system has about a 2% per 6 months chance of becoming obese, while the average person admitted to the ICU has about a 7% chance of becoming obese in the next 6 months. I can come up with two possible explanations for that:
People who are admitted to the ICU gain about 3.37x more weight, on average, than people who do not get COVID-19, and as such are about 3.37x more likely to become obese.
Getting COVID-19 has very little effect on your weight, but within the group of people who are not obese, the people who are closer to the threshold of obesity are more likely to be admitted to the ICU for COVID-19.
I don’t have hard evidence one way or the other, but I did some searching for evidence that COVID-19 causes weight gain, and while I found a large number of articles talking about how people are gaining weight under lockdown, I didn’t find any discussing weight gain from COVID-19 directly. Additionally, my prior is that controlling for confounding factors is really really hard, and so even for a study published in Nature I would not be surprised if the authors failed to perfectly control for those confounding factors.
I’d be interested to see what you get if you
Look at weight changes in a group of people who tested positive vs negative for COVID-19 in a specific narrow period, to see if the COVID-positive people experienced more weight gain over that period, controlling for weight at the start of that period (and if so, whether that weight gain was correlated with disease severity).
Reproduce this study, except look the relative risk of experiencing one of these negative sequelae in the 6 month period before a positive COVID-19 diagnosis (if this method successfully controls for confounding factors, doing this should show a hazard ratio very close to 1 for all conditions, assuming that getting COVID can’t cause you to experience negative health outcomes in the past).