People who are genetically predisposed toward obesity or having high levels of so-called “bad” cholesterol — low-density lipoprotein (LDL) cholesterol — are at increased risk of contracting COVID-19, a study reported.
The study, “Causal Inference for Genetic Obesity, Cardiometabolic Profile and COVID-19 Susceptibility: A Mendelian Randomization Study,” was published in the journal Frontiers in Genetics.
Recent studies have indicated that high body mass index (BMI) — a ratio of weight to height, commonly used as a surrogate marker of obesity — is linked with an increased risk of more serious outcomes from COVID-19 infection (e.g., requiring respiratory support). However, these studies could not assess cause-and-effect relationships between obesity and COVID-19 risk.
Researchers in the U.K used a technique called Mendelian randomization to better understand the causal links of COVID-19 with obesity and obesity-related conditions. Put simply, this type of analysis uses genetic markers to determine the effect of a risk factor on a given outcome, while reducing the impact of confounding variables.
Using the UK Biobank, the researchers analyzed data for 1,211 people who tested positive for SARS-CoV-2 (the virus that causes COVID-19), and 387,079 individuals who were either untested or tested negative between March 16 and May 31. People with a positive test were more likely to be older, male, impoverished, and had a higher prevalence of heart and metabolic risk factors.
The analysis indicated that people with genetic predisposition toward a high BMI were significantly more likely to test positive for the virus, by about 15%. Waist circumference, another common measure of obesity, was not significantly associated with a positive test risk.
In addition, those with a genetic predisposition toward higher LDL cholesterol were about 58% more likely to test positive.
Other obesity-related measures, namely high blood pressure and diabetes, were not significantly associated with a risk of testing positive for the new coronavirus.
“This is the first study to identify the causal relationships between BMI, LDL cholesterol and susceptibility to SARS-CoV-2 infection,” the researchers wrote.
Subsequent analyses showed that individuals in the top 20% of genetic BMI or LDL cholesterol risk had an especially high likelihood of testing positive for SARS-CoV-2.
“Our findings support the use of BMI and LDL cholesterol as important metrics alongside other known characteristics (such as age and ethnicity) in the risk assessment of vulnerability to COVID-19 infection,” Nay Aung, PhD, the study’s lead author with Queen Mary University of London, said in a press release.
The investigators said their study has some limitations — most notably, the UK Biobank has relatively little data from non-European individuals, so the analysis included only Caucasians.
“This is especially important due to the disproportionate impact of COVID-19 on non-White individuals,” the scientists wrote. “Future MR [Mendelian randomization] studies should investigate the influence of cardiometabolic risk factors on COVID-19 in populations of African and other ancestries to better inform the public health policies.”
Still, these findings may help to inform public health policies.
“Those who fall in the at-risk obese category or those with extreme hyperlipidemia [high fat levels] in the general population may require more rigorous social distancing or shielding,” the team added.
We are sorry that this post was not useful for you!
Let us improve this post!
Tell us how we can improve this post?