Can the mini nutritional assessment (MNA®) be used as a nutrition evaluation tool for subacute inpatients over an average length of stay?

Objectives: The prevalence of malnutrition in subacute inpatient settings has been reported to be 30–50%. While there are a number of nutrition evaluation tools which have been validated to diagnose malnutrition, the use of a validated nutrition evaluation tool to measure changes in nutritional status during an average length of stay for a subacute inpatient has not yet been tested. This study aims to determine the potential of the full MNA® (full Mini Nutritional Assessment) and MNA® (Mini Nutritional Assessment Short Form) scores to measure change in nutritional status over an average subacute inpatient stay (21 days). Design: A prospective observational study. Setting: The study was performed in three Rehabilitation and Geriatric Evaluation and Management (GEM) wards of the Kingston Centre, Monash Health, Melbourne, Australia. Participants: All patients ≥65 years admitted to these wards with an expected length of stay of at least 14 days were considered for inclusion in this study. Measurements: Nutritional status was assessed on admission using the full MNA® as part of usual dietetic care and patients were provided with nutrition intervention/diet therapy based on full MNA® classification. Full MNA® score (0–30), MNA® score (0–14), anthropometry (weight and height) and nutritional biochemistry (serum albumin, transthyretin and C-reactive protein) were compared between admission and day 20.5 ± 2.4. Results: Mean age (± SD) of 83 ± 7 years, n=114. For those patients diagnosed at risk of malnutrition or malnourished (n=103), there were significant increases in full MNA® score (1.8 ± 2.4, p<0.001), MNA® score (0.9 ± 1.7, p<0.001), weight (0.6 ± 2.5kg, p=0.017) and serum albumin (1.4 ± 4.4g/L, p=0.003) over the study period. All four of the full MNA® domain sub-scores, also increased significantly in those patients diagnosed at risk of malnutrition or malnourished (n=103): anthropometric assessment (p<0.001), dietary assessment (p<0.001), general status assessment (p=0.019) and self-perceived health and nutrition states (p=0.033). Conclusion: Both the MNA® and full MNA® can be used to evaluate nutrition progress within the subacute inpatient setting over a three week time period, thereby providing clinicians with feedback on a patient’s nutrition progress and assisting with ongoing care planning. Due to its ease of use and shorter time required to complete, the MNA® may be the preferred nutrition evaluation tool in this setting.