Malnutrition Diagnosed by Patient-Generated Subjective Global Assessment and the Risk of All-Cause Mortality in Adults With Gastrointestinal Cancer: A Systematic Review and Meta-Analysis

Introduction: Several reviews have highlighted that the Patient-Generated Subjective Global Assessment (PG-SGA) is the best diagnostic tool for assessing nutritional status in cancer patients. However, previous meta-analyses summarizing the prevalence of malnutrition and overall survival in patients with gastrointestinal (GI) cancer are quite limited. This study aims to determine the overall prevalence and association between malnutrition, as defined by the PG-SGA, and mortality in adults with GI cancer.

Methods: A comprehensive systematic review of articles published from 2005 to 2023 was conducted using Google Scholar, PubMed, Web of Sciences and Scopus. The PRISMA guideline was followed to organize the entire content. A random-effects meta-analysis model using R Studio was performed to quantify the pooled proportion and hazard ratios (HRs). Publication bias was assessed using Egger's test and funnel plots. Heterogeneity was evaluated using I² and Baujat plots. This study was registered in PROSPERO under the protocol number CRD42023465685.

Results: In this study, 46 publications with 23,235 participants were included in the final meta-analysis. The overall prevalence of malnutrition among adults with GI cancer, as determined by the PG-SGA, was 61% (95% CI: 51%-70%, I² = 99%). The pooled prevalence of moderate and severe malnutrition were 38% (95% CI: 31%-45%, I² = 96%) and 21% (95% CI: 13%-31%, I² = 98%), respectively. By cancer type, malnutrition was more common in patients with oesophageal cancer (78%, 95% CI: 45%-94%, I² = 99%) and gastric cancer (75%, 95% CI: 68%-81%, I² = 87%). Additionally, the overall risk (pooled HR) of malnutrition on mortality among GI cancer patients was 2.02 (95% CI: 1.63%-2.5%, I² = 23%).

Conclusion: Malnutrition is common in adults with GI cancer and doubles the risk of all-cause mortality. These results emphasize the importance of ongoing efforts in prevention, early assessment, and intervention for malnutrition to minimize mortality rates.