Association of energy and protein delivery with mortality in critically ill patients with low muscularity assessed by computed tomography: A single-center retrospective study

Abstract

Background and aims

In the critically ill population, low skeletal muscle mass and quality are associated with worse patient outcomes. Since nutrition may attenuate muscle loss, we aimed to determine whether energy and/or protein delivery during critical illness is associated with 60-day mortality in patients with low muscularity.

Methods

This retrospective study included intubated patients with intensive care unit (ICU) stay of ≥72 h and computed tomography (CT) scan within 72 h of admission covering L1/L3 level. Skeletal muscle area (SMA), skeletal muscle density (SMD), and intermuscular adipose tissue were quantitatively derived. CT parameters that independently predicted 60-day mortality were used to establish low muscularity cutoffs using receiver operating characteristics curve analysis. The associations between energy and protein delivered during the first 14 days in ICU with 60-day mortality in low muscularity subgroups were evaluated using multivariable logistic regressions.

Results

Among the 199 patients included (mean age 53.2 ± 18.5 years, BMI 25.6 ± 6.3 kg/m², APACHE II score 18.5 ± 7.4), SMA (adjusted odds ratio [aOR] 0.977, p < 0.001) and SMD (aOR 0.960, p = 0.007) were independently predicted 60-day mortality. Low muscularity cut-offs were SMA 119.1/80.8 cm² and SMD 39.4/19.7 HU in males/females, respectively. Energy and protein delivery during the ICU stay were not associated with 60-day mortality in patients with low SMA, low SMD, or low SMA + SMD.

Conclusion

In critically ill patients, low SMA and low SMD were independently associated with higher mortality risk; however, energy and protein delivery over the first 14 ICU days had no association with 60-day mortality in those with low SMA and/or low SMD.