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New research presented at this year’s European Obesity Congress (online May 10-13) shows a link between increases in body mass index (BMI) and the risk of positive SARS-CoV-2, the virus , which causes COVID-19. The study was conducted by Dr. Hadar Milloh-Raz, Chaim Sheba Medical Center, Tel-HaShomer, Ramat-Gan, Israel, and colleagues.

It is believed that obesity-related factors, including changes in the innate and adaptive immune systems caused by being overweight, are associated with an increased risk of contracting various viral diseases. This relationship between BMI and viral infection risk suggests that there is a similar relationship between a person’s BMI and their risk of developing SARS-CoV-2.

The aim of this study was to evaluate the relationship between BMI and probability test in patients tested for SARS-CoV-2 at the largest medical center in the Middle East. The team analyzed the details of patients tested for the virus over a 9-month period and collected data on BMI, age, gender, and the presence of comorbidities including heart failure (CHF), diabetes mellitus (DM), and high blood pressure ( HTN), ischemic heart disease (IHD), stroke (CVA), and chronic kidney disease (CKD). The study did not look at COVID-19 mortality or outcomes, only the risk of testing positive.

At the beginning of the pandemic, the Chaim Sheba Medical Center put in place a policy that all hospitalized patients, regardless of their symptoms or the reason for admission (whether they had COVID-19 or completely different), would be tested for COVID-19 for reasons like elective surgery, traffic accidents). A total of 26,030 patients were tested during the study period (between March 16 and December 31, 2020) and 1,178 positive COVID-19 results were recorded. The number of patients in each BMI category and the proportion of positive tests varied as shown in the table:

New study: increase in BMI and risk of testing positive for SARS-CoV-2

The authors found that the likelihood of testing positive for SARS-CoV-2 was significantly higher in overweight or obese patients compared to patients with normal BMI. Patients classified as overweight (BMI 25.0-29.9 kg / m2) were 22% more likely to test positive than patients of normal weight (BMI 18.5-24, 9 kg / m2).

Obese patients were even more likely to test positive compared to their normal weight counterparts, and those chances increased with increasing BMI. Class I obesity (BMI 30.0-34.9 kg / m2) was associated with a 27% higher risk of positive tests than that of class II obesity (BMI 35.0-39.9 kg / m2) 38% and an 86% higher risk in class III or morbid obesity (BMI at or over 40.0 kg / m2).

The relationship between BMI and the likelihood of a patient testing positive remained significant even after adjusting for the patient’s age and gender and taking into account any co-morbidities. The authors found that every 1 kg / m2 increase in a patient’s BMI was associated with an increase in the risk of a SARS-CoV-2 positive test of about 2%.

The study also found both positive and negative associations between the risk of testing positive and the presence of comorbidities related to obesity. Diabetes was associated with a 30% higher chance of testing positive, while the risk of testing positive was almost six times higher in patients with high blood pressure. Conversely, the authors found that the likelihood of a positive test in patients with a history of stroke, IHD, and CRF were 39%, 55%, and 45% lower, respectively. The authors cannot explain why patients with stroke, IHD, or CKD have a lower risk of testing positive for SARS-CoV-2.

The authors conclude: “When the BMI rises above normal, the likelihood of a positive SARS-CoV-2 test result increases, even when a number of patient variables are taken into account. In addition, some of the comorbidities associated with obesity appear to be either related an increased risk of infection or protection. ”

No increase in outpatient VTE was observed in SARS-CoV-2 positive patients

Provided by the European Association for the Study of Obesity

Quote: New study: Increase in BMI and the risk of testing positive for SARS-CoV-2 (2021, May 11), accessed on May 11, 2021 from https://medicalxpress.com/news/2021-05-bmi -positive-sars-cov -.html

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