Novel nutritional strategies to prevent muscle wasting

Urea to creatinine ratio as a predictor of persistent critical illness

INTRODUCTION

Persistent critical illness (PCI) is a syndrome in which the acute presenting problem has been stabilized, but the patient's clinical state does not allow ICU discharge. The burden associated with PCI is substantial. The most obvious marker of PCI is prolonged ICU length of stay (LOS), usually greater than 10 days. Urea to Creatinine ratio (UCr) has been suggested as an early marker of PCI development.

METHODS

A single-center retrospective study. Data of patients admitted to a general mixed medical-surgical ICU during Jan 1st 2018 till Dec 31st 2022 was extracted, including demographic data, baseline characteristics, daily urea and creatinine results, renal replacement therapy (RRT) provided, and outcome measures - length of stay, and mortality (ICU, and 90 days). Patients were defined as PCI patients if their LOS was >10 days. We used Fisher exact test or Chi-square to compare PCI and non-PCI patients. The association between UCr with PCI development was assessed by repeated measures linear model. Multivariate Cox regression was used for 1 year mortality assessment.

RESULTS

2098 patients were included in the analysis. Patients who suffered from PCI were older, with higher admission prognostic scores. Their 90-day mortality was significantly higher than non-PCI patients (34.58% vs 12.18%, p < 0.0001). A significant difference in UCr was found only on the first admission day among all patients. This was not found when examining separately surgical, trauma, or transplantation patients. We did not find a difference in UCr in different KDIGO (Kidney Disease Improving Global Outcomes) stages. Elevated UCr and PCI were found to be significantly associated with 1 year mortality.

CONCLUSION

In this single center retrospective cohort study, UCr was not found to be associated with PCI development.

Developing and validating a Modified Cachexia Index to predict the outcomes for colorectal cancer after radical surgery

BACKGROUND

It was reported that the cachexia index (CXI:ALB * SMI NLR ) was an essential index for predicting the prognosis of tumor patients. However, since for SMI needs to be measured by CT imaging methods and its calculation was inconvenient. Thus, we developed a modified cachexia index (mCXI:ALB NLR * UCR ). The purpose of this study was to evaluate the association between mCXI and prognosis in patients with colorectal cancer.

METHODS

An analysis of 215 patients with newly diagnosed colorectal cancer was carried out retrospectively. An optimal cut-off value of mCXI was established by the receiver operating characteristic (ROC) curves for predicting prognosis. Prognostic implications of mCXI were investigated using Kaplan-Meier curves and Cox regression analysis. A comparative assessment of the predictive capacity between mCXI and the CXI was performed using time-dependent receiver operating characteristic analysis.

RESULTS

Patients were classified into two groups based on the cut-off value of mCXI: the LOW mCXI group (n = 60) and the HIGH mCXI group (n = 155). The 3-year Overall survival (OS) (76.6% vs 96.7%, p < 0.01) and 3-year Recurrence-free survival (RFS) (68.3% vs 94.1%, p < 0.01) were significantly worse in the LOW mCXI group in contrast to that in the HIGH mCXI group. In Cox multivariate regression analysis, mCXI was an independent prognostic factor for OS (HR = 8.951, 95%CI: 3.105-25.807, <0.01). Moreover, compared with CXI (AUC = 0.723), mCXI (AUC = 0.801) has better predictive efficacy, indicating that mCXI is more suitable for prognostic assessment.

CONCLUSIONS

The mCXI significantly correlated with survival outcomes for colorectal cancer patients after radical surgery.

Persistent inflammation, immunosuppression, and catabolism syndrome (PICS): a review of definitions, potential therapies, and research priorities

Persistent Inflammation, Immunosuppression, and Catabolism Syndrome (PICS) is a clinical endotype of chronic critical illness. PICS consists of a self-perpetuating cycle of ongoing organ dysfunction, inflammation, and catabolism resulting in sarcopenia, immunosuppression leading to recurrent infections, metabolic derangements, and changes in bone marrow function. There is heterogeneity regarding the definition of PICS. Currently, there are no licensed treatments specifically for PICS. However, findings can be extrapolated from studies in other conditions with similar features to repurpose drugs, and in animal models. Drugs that can restore immune homeostasis by stimulating lymphocyte production could have potential efficacy. Another treatment could be modifying myeloid-derived suppressor cell (MDSC) activation after day 14 when they are immunosuppressive. Drugs such as interleukin (IL)-1 and IL-6 receptor antagonists might reduce persistent inflammation, although they need to be given at specific time points to avoid adverse effects. Antioxidants could treat the oxidative stress caused by mitochondrial dysfunction in PICS. Possible anti-catabolic agents include testosterone, oxandrolone, IGF-1 (insulin-like growth factor-1), bortezomib, and MURF1 (muscle RING-finger protein-1) inhibitors. Nutritional support strategies that could slow PICS progression include ketogenic feeding and probiotics. The field would benefit from a consensus definition of PICS using biologically based cut-off values. Future research should focus on expanding knowledge on underlying pathophysiological mechanisms of PICS to identify and validate other potential endotypes of chronic critical illness and subsequent treatable traits. There is unlikely to be a universal treatment for PICS, and a multimodal, timely, and personalised therapeutic strategy will be needed to improve outcomes for this growing cohort of patients.