Physical Activity and Decreased Risk of Severe COVID-19 Illness[COVID-19 and Physical Activity Series]

Modifiable lifestyle factors and severe COVID-19 risk: Evidence from Mendelian randomization analysis by Dr. Li explored the causal relationship between severe COVID-19 illness and four lifestyle factors—physical activity, obesity, smoking, and alcohol consumption.  Mendelian randomization is a method using exposure-associated genetic variants as instrumental variables to assess the causal relationship between exposures and outcomes.  Dr. Li found that genetically predicted BMI was associated with about 2-fold (1.91, 95% confidence interval [CI], 1.55, 2.35, P=7.4 x 10-10) increased risk of severe COVID-19 illness.  He also found that lifetime smoking was associated with about 2-fold (1.84, 95% CI, 1.08 to 3.13, P=0.02) increased risk of severe COVID-19 illness.  Dr. Li noted this is the first study providing evidence that physical activity causally decreases the risk of severe COVID-19 illness. Genetically predicted physical activity was associated with about 5-fold (95% confidence interval [CI], 1.4, 20.3; P=0.02) decreased risk of severe COVID-19 illness. This study highlights the importance of maintaining a healthy lifestyle in protecting from COVID-19 severe illness and its public health value in fighting against the COVID-19 pandemic. 

Li, S. (2020). Modifiable lifestyle factors and severe COVID-19 risk: Evidence from Mendelian randomization analysis. medRxiv (preprint).