Validation of nutritional risk index method against patient-generated subjective global assessment in screening malnutrition in colorectal cancer patients

Objective

To validate malnutrition screening tool of nutrition risk index (NRI) against patient-generated subjective global assessment (PG-SGA) as a gold standard tool in colorectal cancer patients before radiotherapy.

Methods

Nutritional status of 52 volunteer colorectal cancer patients with a mean age of 54.1±16.8 years who referred to radiotherapy center were assessed by PG-SGA (gold standard method) and NRI. Serum albumin levels of patients were determined by colorimetric method. A contingency table was used to determine the sensitivity, specificity, and predictive value of the NRI in screening patients at risk of malnutrition, in comparison with the PG-SGA in patients before radiotherapy.

Results

The findings of PG-SGA and NRI showed that 52% and 45% of patients in our study were moderately or severely malnourished respectively. The NRI had a sensitivity of 66% and a specificity of 60% against PG-SGA. The positive predictive value was 64% and the negative predicative value was 62%. The agreement between NRI and PG-SGA was statistically insignificant (kappa =0.267; P>0.05).

Conclusions

The findings of present study showed that the prevalence of malnutrition was high in patients with colorectal cancer. Moreover, NRI method had low sensitivity and specificity in assessing nutritional status of patients with cancer. It seems that the combination of anthropometric, laboratory parameters and a subjective scoring system may be helpful tools in screening of malnutrition in cancer patients.