From the Guidelines
Diagnosing malnutrition requires a comprehensive assessment using the Global Leadership Initiative on Malnutrition (GLIM) criteria, which includes a two-step approach with validated screening and detailed assessment of phenotypic and etiologic criteria. The diagnostic criteria for malnutrition, as defined by the European Society for Clinical Nutrition and Metabolism (ESPEN), include a BMI of <18.5 or the combined finding of unintentional weight loss and either reduced BMI or a low fat-free mass index 1. Unintentional weight loss is defined as weight loss of >10% over an indefinite time or >5% over 3 months. The GLIM criteria propose a two-step approach for malnutrition diagnosis, which includes a validated screening and a detailed assessment with phenotypic and etiologic criteria for diagnosis and grading the severity of malnutrition 1.
Key Diagnostic Criteria
- BMI of <18.5
- Unintentional weight loss of >10% over an indefinite time or >5% over 3 months
- Reduced BMI or low fat-free mass index
- Phenotypic criteria: unintentional weight loss, low BMI, and reduced muscle mass
- Etiologic criteria: reduced food intake and inflammation/disease burden
Screening Tools
- Nutritional Risk Screening (NRS-2002)
- Subjective Global Assessment (SGA)
- Nutrition Risk Index
- Perioperative Nutrition Score (PONS)
- Malnutrition Universal Screening Tool (MUST)
- Mini Nutritional Assessment (MNA)
Importance of Early Diagnosis
Early diagnosis of malnutrition is crucial as it increases infection risk, delays wound healing, prolongs hospital stays, and increases mortality rates 1. Regular reassessment is necessary to monitor nutritional status and response to interventions. The use of validated screening tools and detailed assessment of phenotypic and etiologic criteria can help identify at-risk patients and guide nutritional interventions.
From the Research
Diagnostic Criteria for Malnutrition
The diagnostic criteria for malnutrition involve various parameters, including:
- Anthropometric measurements, such as body mass index (BMI) and fat free mass index (FFMI) 2
- Laboratory values, such as those indicating vitamin and mineral deficiencies 3, 4
- Physical examination, including evaluation of muscle mass, fat stores, edema, and functional capacity 3, 4
- Unintentional weight loss, with specific thresholds (e.g., >10% of habitual weight or >5% over 3 months) 2
Malnutrition Diagnostic Tools
Several diagnostic tools are currently used to identify malnutrition in adults, including:
- Subjective Global Assessment (SGA) 3, 5
- Mini Nutritional Assessment 5
- Academy of Nutrition and Dietetics/American Society for Parenteral and Enteral Nutrition (AND/ASPEN) malnutrition consensus characteristics 3, 5, 6
- Global Leadership Initiative on Malnutrition criteria 5
Standardized Definition for Malnutrition Diagnoses
A standardized definition for malnutrition diagnoses was developed by the Academy of Nutrition and Dietetics and the American Society for Parenteral and Enteral Nutrition (AND/ASPEN) in 2012, which incorporates a set of diagnostic characteristics to identify and document adult malnutrition 6. The European Society of Clinical Nutrition and Metabolism (ESPEN) also recommends a consensus-based minimum set of criteria for the diagnosis of malnutrition, including two options: a BMI <18.5 or the combined finding of unintentional weight loss and at least one of either reduced BMI or a low fat free mass index (FFMI) 2.