Cellular and Biochemical Mechanisms Driving the Susceptibility of Obese Subjects to Covid-19 Infection

Abstract

Overweight is a major global health problem currently affecting almost 2 billion people worldwide. An additional 800 million are obese. These figures showed that 40% of the global adult population aged 18 years, and over are overweight while 14% are obese. What is now worrying is that more than 40 million children worldwide, as young as 5 years of age are either overweight or obese. Individuals with a body mass index (BMI) of 25–29 kg/m2 are considered to be overweight while obesity is the term used when the BMI is 30 kg/m2 and over. Obesity is an imbalance between calorie intake and calorie expenditure. In general, obesity can be caused by excessive eating and reduced physical activity. Obesity is a major risk factor for non-communicable diseases such as diabetes mellitus, respiratory and liver dysfunctions, sleep apnea, chronic inflammation, compromised immune system, renal failure, cancer, musculoskeletal disorders, cardiovascular diseases and others. Obesity is also a major risk factor for coronavirus disease 19 (Covid-19), which can induce severe cases of pneumonia and sepsis or acute respiratory distress syndrome. In many cases, Covid-19 causes severe and long-lasting damage to the lungs and other vital organs of the body resulting in death. This review describes the cellular and biochemical mechanism(s) whereby obese patients become susceptible to Covid-19 infection. It also outlines how obesity on its own can affect the lungs, which in turn become more compromised in cases of Covid-19 disease resulting in the imminent death of the patient.