Clinical Nutrition in Covid-19 Patients - A Systematic Review

Introduction There is currently a lack of evidence on clinical nutrition in Covid-19. Aim of the work: Systematic overview of clinical nutrition in Covid-19.Material and methods A systematic literature search: 2 meta-analyses, 12 systematic reviews and meta-analyses, 9 prospective randomized controlled trials, 3 prospective observational studies, 7 retrospective studies, 25 narrative reviews.Results a) Obese patients have an increased risk of a severe course of the disease, b) there is a connection between obesity and an increased risk of death, c) Covid-19 mortality increases from a BMI>27 kg/m(2), in all BMI classes 1,6% per 1 kg/m(2) in the event of weight gain, in the case of severe obesity (> 40-45 BMI) by a factor of 1,5 to 2 and per 5 kg/m(2), d) the risk of a severe course of Covid-19 increases also with increased visceral fat tissue percentage, total body fat mass and upper abdominal circumference, e) the mortality rate can be 10 times higher in malnourished Covid-19 patients, f) serum albumin provides evidence of a poor course of the disease, g) enteral omega-3 fatty acid intake could stabilize kidney function and improve the outcome, h) foods with a low glycemic index should be preferred, i) vitamin D deficiency should be avoided, daily vitamin D and zinc supplementation can be beneficial, j) one-time high dose vitamin D and enteral vitamin C provide no benefit, but the risk of thrombosis could be reduced and the antibody response enhanced with zinc, k) nutritional intervention reduces mortality.Conclusion Screening and assessment of nutritional status are important in Covid-19 patients. Overall, there are insufficient clinical results on specific nutritional therapy.