Association between nutritional indices and mortality after hip fracture: a systematic review and meta-analysis

This study analyzed evidence on the association between prognostic nutritional index (PNI), controlling nutritional status (CONUT), geriatric nutritional risk index (GNRI), and mini-nutritional assessment-short form (MNA-SF) and mortality after hip fracture.

The online databases of PubMed, Scopus, Web of Science, Embase, and Google Scholar were accessed for literature reporting the association between PNI/CONUT/GNRI/MNA-SF and mortality after hip fracture. Data were pooled in a random-effects model.

13 studies were eligible. Meta-analysis of six studies showed that individuals with low GNRI had a significantly higher risk of mortality as compared to those with high GNRI (OR: 3.12 95% CI: 1.47, 6.61 I2=87% p=0.003). Meta-analysis of three studies found that low PNI was not a significant predictor of mortality amongst hip fracture patients (OR: 1.42 95% CI: 0.86, 2.32 I2=71% p=0.17). On pooling data from five studies, it was noted that patients with low MNA-SF scores had a significantly higher risk of mortality in comparison to those with higher scores (OR: 3.61 95% CI: 1.70, 7.70 I2=85% p=0.0009). Only one study was available on CONUT. Heterogeneity of cut-offs and variable follow-up were important limitations.

Our results indicate that MNA-SF and GNRI can predict mortality in elderly patients undergoing surgery for hip fractures. Data is scarce on PNI and CONUT to draw strong conclusions. Variation in cut-offs and follow-up period are important limitations which need to be addressed by future studies.