Recent studies report that a high proportion of young adults who are hospitalized to the intensive care unit because of the Covid-19 are obese.
If there’s one thing that the current pandemic of Covid-19 has helped to highlight, is how much the general health status of infected individuals influence the risk of developing serious complications of the disease. There has been much emphasis on age as a main risk factor of mortality of the Covid-19, and it is undeniable that the constant decrease of the efficiency of the immune system during aging contributes to the greater vulnerability of older people to the virus. However, it must be repeated : more than 90 % of the people who died as a result of the Covid-19 had one or more comorbidities at the time of infection, the most common being obesity, cardiovascular disease and type 2 diabetes. In other words, this is not only the age, but especially the state of metabolic health of infected people, which largely determines the risk that the Covid-19 evolves into more severe forms.
The risks of overweight
Being overweight is certainly one of the factors that have a determining influence on the metabolic health. Excess fat generates a state of chronic inflammation that contributes to the development of several metabolic abnormalities (hyperglycemia, dyslipidemia, hypertension), and significantly increases the risk of cardiovascular disease, type 2 diabetes and several types of cancers. Obesity generates, therefore, of the pathological conditions which are now all recognised to increase the risk of Covid-19 severe. The overweight also disrupts the effectiveness of the immune system, and can therefore make the obese people more susceptible to viral infections. In this sense, a recent analysis indicates that obese people have a 40% higher risk of being infected by the SARS-CoV-2 than slender individuals(1). In sum, being overweight is very often a synonym of poor metabolic health and must therefore be considered as a risk factor for Covid-19.
Over the past 20 years, there has been a significant increase in and constant of overweight and obesity among citizens of industrialized countries, including children and young adults. Several recent studies have reported that overweight increases the risk of COVID-19 severe in patients under 60 years of age, representing a segment of the population that would not normally be at high risk of complications.
An american study has recently shown that the risk of serious complications from the Covid-19 was 2 times higher among young obese adults compared to patients of normal weight(2). An article recently published in the prestigious medical journal the Lancet arrives at similar conclusions, that is to say that young adults with the Covid‐19 who were obese had a greater probability of being admitted to the intensive care unit because of clinical complications(3). Even overweight children are more at risk : an analysis of 48 children (mean age 13 years) with the Covid-19 and hospitalized in the intensive care units, pediatric has shown that obesity was the main comorbidity observed in these young patients, with the exception of congenital diseases and cancer(4).
These data thus show that in populations with a high prevalence of overweight people, the Covid-19 may affect a greater proportion of young adults on suspicion. In Canada, 64% of the population is overweight, of which 29% are obese, and these people are more at risk of contracting the Covid-19 and to develop severe complications from the disease than the general population, and this, even at a young age.
(1) de Lusignan S, et al. Risk factors for SARS-CoV-2 among patients in the Oxford Royal College of General Practitioners Research and Surveillance Centre primary care network: a cross-sectional study. Lancet Infectious Dis., published on may 15, 2020.
(2) Lighter J et al. Obesity in patients younger than 60 years is a risk factor for Covid-19 hospital admission. Clin. Infect Dis., published April 9, 2020.
(3) Kass DA et al. Obesity could shift severe COVID-19 disease to younger ages. Lancet 2020; 95:1544-1545.
(4) Shekerdemian LS et al. Characteristics and outcomes of children with coronavirus disease 2019 (COVID-19) infection admitted to US and Canadian pediatric intensive care units. JAMA Pediatr., published on may 11, 2020.