Coronavirus linked to greater risk of life-threatening infection in people with obesity
As worldwide coronavirus-related deaths tip a quarter of a million, a concerning trend is surfacing in the medical literature: high rates of obesity in groups of patients with severe or life-threatening COVID-19.
A recent report from New York shows more than two in every five people requiring a breathing tube were obese. A report from one intensive care unit in France found almost 90% of morbidly obese patients admitted required mechanical ventilation compared to less than half of those with lower body weight.
There are several reason why patients with obesity admitted to intensive care with COVID-19 may require invasive ventilation.
Higher levels of fat in the chest and belly put pressure on the lungs, making it difficult for people with obesity to fill them to capacity under normal circumstances. This reduced breathing capacity may add to respiratory distress in patients with COVID-19.
Carrying extra weight also means there is higher oxygen demand. Some patients with obesity might breathe too shallowly or too slowly to provide enough oxygen to the body, and some may intermittently cease breathing altogether.
Both of these factors already put strain on the heart and lungs, and may worsen COVID-19 symptoms. But they don’t seem to entirely explain the unexpectedly high rates of obesity in very sick coronavirus infected patients. This suggests that there may be other factors at play which are unique to this virus.
In a recent review paper, we looked at why patients with obesity are at higher risk of severe or life-threatening COVID-19 infections. Based on our findings, we believe fat tissue is a potential source of unchecked inflammation which could cause damage to organs, including the lungs, as a result of COVID-19.
People with obesity are commonly shown to have an unbalanced or inflamed immune system. Their blood often has higher levels of several inflammatory signals which are similar to COVID-19 responses in the body. This may mean their immune systems are more likely to overreact to a coronavirus infection.
