Nutritional therapy and outcomes in underweight critically ill patients

Background & aims: Critically ill patients with body mass index (BMI) < 20 kg/m2 have worse outcomes than normal/overweight patients possibly because underweight is a marker of malnutrition. To assess the effects of nutrition therapy in this population during the first week of an ICU stay. Methods: Prospective, 2-centre, observational study. Nutritional evaluations were performed between days 2 and 3 (first) and between days 5 and 7 (second) of ICU admission. In the first evaluation, patients were divided into non-fed (without nutritional support) and early-fed (those already receiving nutritional support) groups. In the second evaluation, patients were divided according to caloric intake (≥or<20 kcal/kg) and protein intake (≥or