MUST Nutritional Screening: Indications for Adult Patients
The Malnutrition Universal Screening Tool (MUST) should be used for initial nutritional screening in all adult patients in community settings, outpatient clinics, and general hospital wards, particularly when patients cannot be weighed or measured, as it demonstrates superior specificity and criterion validity compared to other screening tools. 1
Primary Indications by Clinical Setting
Community-Dwelling Adults
- All older adults (≥65 years) living in the community should be screened with MUST, as it has been validated for use in this population and can identify malnutrition risk even when weight cannot be measured 1, 2
- MUST is particularly indicated for community-dwelling elderly who may have difficulty accessing traditional anthropometric measurements 2
Hospitalized Patients
- All acutely ill hospitalized adults, especially elderly patients (≥65 years), should be screened with MUST within 24 hours of admission 1, 3
- MUST is specifically indicated when patients cannot be weighed or measured, as it can utilize subjective criteria (recalled weight, visual assessment) while maintaining predictive validity 3
- In hospitalized elderly, MUST predicts both in-hospital and post-discharge mortality (P<0.01) and length of hospital stay (P=0.02) 3
High-Risk Populations Requiring MUST Screening
- Older adults at high risk of hospital readmission should be screened with MUST, as it demonstrates substantial sensitivity and specificity in this population 4
- Patients with chronic diseases including those with excessive nutrient losses (vomiting, diarrhea, fistulae) or high metabolic demands (surgical stress, trauma, infection) 1
- Patients staying >48 hours in hospital who are at risk for hospital-acquired malnutrition 1
MUST Performance Characteristics
Comparative Advantages
- MUST demonstrates better specificity than other screening tools (NRS-2002, MNA, MNA-sf, NRI) when compared in systematic reviews 1
- MUST shows better criterion validity alongside MNA compared to other validated screening tools 1
- MUST can screen 100% of patients even when only 56% can be weighed, unlike tools requiring measured anthropometrics 3
Clinical Outcomes Predicted by MUST
- Mortality risk: Both in-hospital and post-discharge mortality are significantly higher in patients identified as at-risk by MUST (P<0.01) 3
- Length of hospital stay: Patients at malnutrition risk by MUST have significantly longer hospitalizations (P=0.02) 3
- All MUST component scores (BMI, weight loss, acute disease) independently predict mortality (P<0.03) 3
Important Clinical Caveats
When MUST Has Limitations
- MUST has low sensitivity in patients with kidney disease (AKI/AKD/CKD) due to its inability to account for fluid overload and kidney-specific risk factors such as anorexia 1
- For kidney disease patients, consider using NRS-2002 or the Renal iNUT tool instead 1
When Alternative Tools Are Preferred
- For critically ill ICU patients: Use mNUTRIC score, which demonstrates good predictive validity for ICU-related complications and 28-day mortality (adjusted HR=2.01,95% CI: 1.22-3.32, P=0.006) 1
- For geriatric patients with cognitive dysfunction: Consider MNA-SF, which has been specifically validated for this population 5
- For hospitalized patients with acute illness: NRS-2002 is recommended by ESPEN as the primary tool based on extensive validation 1
Practical Implementation
Screening Frequency
- Initial screening should occur within 24 hours of hospital admission 5
- Re-screening should occur every 7-10 days during hospitalization for all patients 5
- Community-dwelling stable patients require rescreening every 3-6 months 6
Documentation Requirements
- Record the specific MUST score with numerical values in the patient's health record 6
- Document presence of key criteria: unintentional weight loss percentage, reduced dietary intake, BMI category 6
- Patients screening positive (MUST score ≥2) require immediate referral to a registered dietitian for comprehensive assessment 5, 6