A recent study conducted by researchers at Mass General Brigham has highlighted obesity as a significant risk factor for contracting the virus responsible for COVID-19. The analysis of electronic health records revealed that those with obesity are 34% more likely to test positive for COVID-19 after being exposed to the virus compared to those without obesity. Published in PNAS Nexus, the findings suggest that obesity, previously recognized for increasing the severity of COVID-19 symptoms and complications, may also heighten the risk of initial infection.
“We already knew that obesity increases the risk of severe outcomes from COVID-19, but we were caught off guard by our discovery that it also raises the chances of getting the virus initially,” explained Masanori Aikawa, MD, PhD, the study’s corresponding author and director of the Center for Interdisciplinary Cardiovascular Sciences (CICS) at Brigham and Women’s Hospital. “This indicates that obesity could have a more significant effect on the spread of COVID-19 than we had previously understood. Our findings reinforce the importance of achieving and maintaining a healthy weight for better overall health.”
The research, led by first author Joan T. Matamalas, PhD, a research scientist at CICS, involved a case-control study that assessed data collected in the Mass General Brigham COVID-19 Data Mart, which consists of COVID-19 test results from 687,813 individuals tested between March 2020 and March 2022—a time marked by widespread infection before vaccines became available. The study focused on over 72,000 participants who reported exposure or potential exposure to COVID-19.
The authors acknowledge that the study relied on self-reported data regarding possible exposure, which may not fully reflect reality, and it was conducted within a single health system in Massachusetts, potentially limiting the applicability of the results to other groups. Future research could investigate the biological factors that may increase susceptibility in those with obesity, which could lead to new treatment targets or tailored vaccination strategies to provide better protection against infection and associated complications.
The researchers emphasize that their findings should remind everyone of the critical need to prioritize good health and minimize risks, especially as COVID-19 case numbers rise.
“Even though our study was based on data from before vaccines were available, many studies have demonstrated that vaccines are the best and safest way to prevent COVID-19 infection and severe outcomes, regardless of a person’s weight or other risk factors,” added Aikawa.
Authorship: In addition to Matamalas and Aikawa, the authors from Mass General Brigham include Sarvesh Chelvanambi, Julius L. Decano, Arda Halu, Diego V. Santinelli-Pestana, Elena Aikawa, and Rajeev Malhotra. The study also includes contributions from Raony F. França.
Funding: This research was partially funded by grants from Kowa Company, Ltd, in Nagoya, Japan (A11014) and the National Institutes of Health (R01HL126901, R01HL149302, R01HL136431, R01HL141917, R01HL147095, and K25HL150336). Kowa did not participate in the study beyond providing funding.
