The COVID-19 pandemic has affected over 60 million people worldwide, of whom nearly 1.43 million have developed severe COVID-19 disease and nearly 40 million have recovered. The COVID-19 disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is serious and leads to life-threatening complications in a small proportion of people. Several risk factors have been linked to severe COVID-19, including obesity.
French researchers, led by lead author Abdallah Al-Salameh from the Department of Endocrinology, Diabetes Mellitus and Nutrition at Amiens University Hospital in Amiens, France, have published results of their study entitled “The relationship between the body mass index class and Coronavirus Disease Results 2019 “published,” In the latest edition of the International Journal of Obesity.
Background and study goals
It is known that obesity, high body mass index and diabetes are risk factors for a severe course of COVID-19. The researchers find, from available scientific evidence, that nearly 40 percent of hospitalized patients with a high BMI are obese. For example, morbid obesity is typically associated with a severe clinical course of the disease they write.
Obesity and COVID-19 Pathology
The researchers explain that people with obesity often have impaired respiratory functions and this causes them to succumb not only to SARS-CoV-2 infection, but to other respiratory infections as well.
In addition, abdominal obesity has been linked to a highly inflammatory disease that can alter the immune response to infections, including COVID-19 disease. People with obesity are almost always diabetic and can have heart disease and other metabolic problems, the researchers explain. These comorbidities make them susceptible to infection with the SARS CoV-2, they add.
The main objective of this study was to quantify the association between body mass index (a measure of obesity) and critical forms of COVID-19. The researchers say this is important in understanding the relationship between obesity and COVID-19, in caring for those in need, and in preventing bad outcomes.
For this study, researchers included consecutive adult patients with laboratory-confirmed COVID-19 who had to be hospitalized. They were all admitted to Amiens University Hospital (Amiens, France). Data on the patients were collected retrospectively from the hospital database.
Confirmed COVID-19 were those cases that were confirmed in the reverse transcriptase polymerase chain reaction (RT-PCR) assay of nasopharyngeal swab specimens. Only those patients or their legal guardians who consented to participate in the study were included in the analysis. For the purposes of this study, patients of normal weight were patients with a BMI of less than 25 kg / m2.
The important parameters recorded were:
- Demographic data such as age, gender, BMI, social factors
- Risk factors
- Medical history
- Medical history of particular concern
- Detailed clinical data
- Routine laboratory results
- Patient results
The primary endpoints of the assessment were:
- Admission to the intensive care unit and
The secondary endpoints of the study were:
- Need for mechanical ventilation
- Diagnosis of acute respiratory distress syndrome (ARDS according to the Berlin criteria) on the discharge note of the intensive care unit
- Diagnosis of acute coronary syndrome (serum level of highly sensitive cardiac troponin Ic above the 99th percentile for the normal population, as seen in the ECG / echocardiogram)
- Acute kidney failure (as per guidelines for improving global kidney disease outcomes)
- Secondary infection
- The total length of hospital stay
Associations between BMI categories and the endpoints were made using logistic regression analysis.
A total of 433 patients hospitalized with COVID-19 were included in the study. An overview of the results is as follows:
- Among 329 patients whose BMI was recorded there were:
- 20 (6.1 percent) were underweight
- 95 (28.9 percent) were of normal weight
- 90 (27.4 percent) were overweight
- 124 (37.7 percent) were obese
- The average age for different BMI categories was:
- Underweight – 84.5 years
- Normal weight – 81 years
- Overweight – 71 years
- Overweight – 66 years
- Intensive care admission was 35.1 percent and for overweight and obese patients 52.6 percent
- Deaths were observed in 23 percent and 36.1 percent in overweight and obese patients, respectively
- The odds ratio for severe illness related to the primary endpoint of death or ICU admission by different BMI categories was as follows:
- Overweight – odds ratio 1.58 [0.77–3.24]
- Obesity – Odds Ratio 2.58 [1.28–5.31]
- The odds ratio for severe illnesses related to ICU admission according to different BMI categories was as follows:
- Overweight – odds ratio 3.16 [1.29–8.06]
- Obesity – Odds Ratio 3.05 [1.25–7.82]
- The unadjusted OPs for deaths were the same for all BMI categories
Conclusions and implications
The team writes: “… obesity was significantly associated with a higher likelihood of the primary endpoint (death or ICU admission) occurring.” The researchers wrote that being overweight is more clearly linked to being admitted to the intensive care unit. The team concluded: “We found that the frequency of the primary endpoint in patients with COVID-19 was twice as high in overweight people as in people with a BMI <25 kg / m2." They called for larger studies in the future other populations to understand the relationship between BMI and adverse outcomes in patients with COVID-19.