Relationship between nutrition and ASA-classification in the elderly

Old age and bad nourishment are risk factors for the postoperative period. In this study, the "mini nutritional assessment" (MNA) of elderly patients was evaluated before the operation and compared with their ASA-classification. 215 outpatients (age > 60 years) were included. MNA-score was fixed as follows: MNA 24 - 30 = normal (MNA I); MNA 17 - 23.5 = risk of malnutrition (MNA II; MNA < 17 = undernourished (MNA III). In addition, the ASA-score of all patients was registered. chi (2)-, Mann-Whitney-U- and correlation analysis were used for statistical analysis. A cut off-value of 24 was fixed for MNA and correlated with the ASA-score. 34.9 % of all patients were allocated to MNA II or III, but only 19.9 % to ASA III or IV. The sensitivity of the ASA-classification for evaluation of the nutritional status was 0.33, selectivity was 0.87, positive predictive value was 0.58 and negative predictive value was 0.70. ASA evaluation is not suitable for assessment of the nutritional status. With regard to typical postoperative complications, the nutritional status of patients should be assessed separately.