Understanding the Malnutrition Universal Screening Tool (MUST)
The Malnutrition Universal Screening Tool (MUST) is a validated tool for identifying malnutrition risk, malnutrition, or obesity in adults. Developed by BAPEN's Malnutrition Advisory Group, MUST is widely used in various healthcare settings such as hospitals, community care, and residential homes. It is valued for its ease of use, speed, and integrated management guidelines linked to risk scores.
MUST assesses risk using three parameters: Body Mass Index (BMI), recent unplanned weight loss, and the effect of acute illness. Each parameter receives a score, which are then added to determine an overall risk category. The crucial fifth step involves applying management guidance based on this risk.
The Five Steps of the MUST Screening Tool
The MUST tool follows a clear, five-step process for healthcare professionals.
Step 1: Calculate the Body Mass Index (BMI)
Measure the patient's height and weight to calculate BMI, then use a chart to assign a score. If direct measurement is not possible, alternative methods like mid upper arm circumference (MUAC) can estimate BMI category.
- Score 0: BMI > 20 kg/m$^2$ (> 20 if < 65 years) or > 22 kg/m$^2$ (> 22 if >= 65 years)
- Score 1: BMI 18.5–20 kg/m$^2$ (18.5–20 if < 65 years) or 20–22 kg/m$^2$ (20–22 if >= 65 years)
- Score 2: BMI < 18.5 kg/m$^2$ (< 18.5 if < 65 years) or < 20 kg/m$^2$ (< 20 if >= 65 years)
Step 2: Assess Unplanned Weight Loss
Determine unplanned weight loss over the past 3-6 months. Calculate the percentage loss to assign a score. This can be a more sensitive indicator of acute nutritional risk than BMI alone.
- Score 0: Unplanned weight loss < 5%
- Score 1: Unplanned weight loss 5–10%
- Score 2: Unplanned weight loss > 10%
Step 3: Consider Acute Disease Effect
Add a score of 2 if acute illness has caused or is likely to cause no nutritional intake for over 5 consecutive days.
Step 4: Add the Scores to Determine Overall Risk
Sum the scores from the first three steps to find the overall malnutrition risk.
- Low Risk: Score of 0
- Medium Risk: Score of 1
- High Risk: Score of 2 or more
Step 5: Develop and Implement a Management Guideline-Based Care Plan
Use the overall risk score to create and implement a management plan based on BAPEN guidelines. Actions vary significantly by risk category.
Comparison of MUST vs. Other Nutritional Tools
| Feature | Malnutrition Universal Screening Tool (MUST) | Mini Nutritional Assessment (MNA) | Nutritional Risk Screening (NRS-2002) |
|---|---|---|---|
| Target Population | General adult population, including older adults. | Primarily validated for older adults (65 years and older). | Hospitalized patients, specifically identifying risks related to critical illness. |
| Assessment Parameters | BMI, unintentional weight loss, and acute illness. | Anthropometrics (BMI, weight loss, calf circumference), dietary intake, mobility, psychological stress. | Severity of disease, weight loss, low BMI, and reduced food intake. |
| Steps/Process | Five distinct steps: score BMI, score weight loss, score acute disease effect, sum scores, apply management guidelines. | Standard 6-question screening for risk, followed by a more detailed assessment if needed. | Initial screening questions followed by a more detailed assessment for hospitalized patients. |
| Management Guidelines | Integrated and linked directly to the final risk score (low, medium, high). | Guidelines are provided based on the risk level determined by the screening/assessment. | Involves a detailed management plan for patients at nutritional risk due to disease. |
| Use Case | Wide range of settings: hospitals, community, and care homes. | Specifically effective in geriatric settings and assessing frailty. | Acute hospital settings where critical illness is a factor. |
Management Guidelines for Each Risk Category
The MUST tool's strength lies in linking risk scores directly to management plans.
- Low Risk (Score 0): Re-screen regularly (weekly in hospitals, monthly in care homes, every 2–3 months in community settings). Provide general health advice.
- Medium Risk (Score 1): Document dietary intake. If inadequate, implement a plan to increase nutritional intake, monitor weight and intake.
- High Risk (Score 2 or more): Prompt referral to a dietitian or nutrition support team for a comprehensive, individualized care plan and close monitoring.
The Role of MUST in Modern Healthcare
MUST standardizes malnutrition risk identification in adults. Its ease of use by various healthcare staff facilitates early intervention, improving patient outcomes, reducing complications, shortening hospital stays, and decreasing readmissions. Integrated guidelines ensure screening leads to actionable steps for better patient care.
Conclusion
The Malnutrition Universal Screening Tool (MUST) is a reliable, five-step tool with vital management guidelines for adult malnutrition risk. It assesses BMI, weight loss, and acute disease effect to assign a risk category linked to a specific care plan. This integration makes MUST crucial for preventing and managing malnutrition, enhancing patient recovery and health. Further details and alternative measurements are available from BAPEN. BAPEN: Malnutrition Universal Screening Tool
