Association of obesity and body mass index classification with glycemic control in adults who are critically ill receiving parenteral nutrition: A retrospective study

Background Hyperglycemia is a complication of parenteral nutrition (PN), which can be exacerbated in patients with obesity. Limited data exist on glycemic control in this population. This study aims to evaluate the association of obesity and body mass index (BMI) classification with glycemic control in patients who are critically ill initiated receiving PN. Methods This is a retrospective study of patients who are critically ill receiving PN from January 2013 to February 2024. The primary outcome was glycemic control in patients with BMI ≥ 30 kg/m 2 or BMI < 30 kg/m 2 based on hyperglycemic episodes, peak blood glucose, and insulin requirements on the first and second days of therapy. Multivariate analyses were conducted for the occurrence of a hyperglycemic episode. The secondary outcome was to determine the association of BMI classification with glycemic control. Results The study included 220 patients with BMI ≥ 30 kg/m 2 ( n = 91) and BMI < 30 kg/m 2 ( n = 129). The BMI < 30 kg/m 2 group received more total dextrose (1.58 vs 2.36 mg/kg/min; P < 0.0001). There was no difference in the primary outcome during day 1 of PN, but there were increased hyperglycemic episodes ( P = 0.0478) and insulin requirements in the BMI ≥ 30 kg/m 2 group on day 2 ( P = 0.0226). The only difference in the secondary outcome was insulin requirements on day 2 ( P = 0.0453). Conclusion Patients who are critically ill with BMI ≥ 30 kg/m 2 receiving PN received more conservative dextrose infusion rates yet experienced more hyperglycemic episodes and required more insulin on day 2. However, obesity and BMI classification were not independently associated with hyperglycemic episodes within the first 2 days of PN initiation.