詳細ガイド 近日公開
Nutritional Risk Score (NRS-2002)の包括的な教育ガイドを準備中です。ステップバイステップの解説、数式、実例、専門家のヒントをお届けしますので、もうしばらくお待ちください。
The Nutritional Risk Screening 2002 (NRS-2002) is a validated malnutrition screening tool developed by Kondrup et al. under the auspices of the European Society for Parenteral and Enteral Nutrition (ESPEN) and recommended by ESPEN guidelines as the preferred screening tool for hospitalised patients. It was designed to identify patients who are both nutritionally compromised and have an increased metabolic demand from severe illness — the combination that most strongly predicts benefit from nutritional support. The NRS-2002 has two components: (1) Nutritional Status Impairment (scored 0–3): 1 = mild (weight loss >5% in 3 months or food intake below 50–75% of normal requirement in the past week); 2 = moderate (weight loss >5% in 2 months or BMI 18.5–20.5 with impaired general condition or food intake 25–50% of normal); 3 = severe (weight loss >5% in 1 month or >15% in 3 months or BMI <18.5 with impaired general condition or food intake 0–25% of normal). (2) Disease Severity (scored 0–3): 1 = mild increased requirements (hip fracture, chronic disease with complications); 2 = moderate increased requirements (major abdominal surgery, stroke, severe pneumonia, haematological malignancy); 3 = severe increased requirements (head injury, bone marrow transplant, ICU patients with APACHE II >10). Additionally, patients aged 70 or above receive an extra 1 point to account for age-related reduced nutritional reserve. A total NRS-2002 score of ≥3 indicates the patient is at nutritional risk and should receive nutritional support. The NRS-2002 is applicable across all adult hospital departments and has been shown in controlled trials to predict which hospitalised patients benefit from nutritional intervention in terms of reduced complications and shorter hospital stay.
NRS-2002 = Nutritional Status Score (0–3) + Disease Severity Score (0–3) + Age ≥70 (+1); Total ≥3 = nutritional support indicated
- 1Screen for nutritional impairment: Is BMI <20.5? Has the patient lost weight recently? Has food intake been reduced? If yes to any, proceed to formal NRS-2002 scoring.
- 2Score Nutritional Status Impairment (0–3): 0 = normal; 1 = mild (>5% weight loss in 3 months or food intake 50–75% of normal for >1 week); 2 = moderate (>5% in 2 months or BMI 18.5–20.5 or intake 25–50% of normal); 3 = severe (>5% in 1 month or >15% in 3 months or BMI <18.5 or intake 0–25%).
- 3Score Disease Severity (0–3): 0 = normal needs; 1 = mild (e.g., hip fracture, chronic illness); 2 = moderate (e.g., major surgery, stroke, COPD exacerbation); 3 = severe (e.g., head injury, ICU with APACHE II >10, BMT).
- 4Add 1 point if patient age ≥70 years.
- 5Sum scores: NRS-2002 ≥3 = at nutritional risk — initiate nutritional support (oral supplements, enteral tube feeding, or parenteral nutrition as appropriate).
- 6For NRS <3: reassess weekly in hospital; nutritional support not currently indicated but may change with clinical deterioration.
- 7Refer to dietitian for personalised nutritional care plan if NRS ≥3, with goals for energy and protein targets.
Target protein: 1.2–1.5 g/kg/day; energy: 25–30 kcal/kg/day
An NRS of 4 indicates nutritional risk. Major surgery creates metabolic demands that require nutritional support to prevent complications and promote wound healing.
Start enteral feeding within 24–48 hours of ICU admission; target 25 kcal/kg/day advancing over 3 days
An NRS of 7 is the maximum score. A severely malnourished elderly ICU patient requires urgent, carefully titrated nutritional support to prevent further deterioration.
Reassess NRS weekly or if clinical situation changes
A well-nourished patient undergoing minor elective surgery has low nutritional risk. No additional nutritional intervention is required.
Hip fracture patients with poor nutritional status have significantly higher complication rates and longer hospital stays
An elderly patient with hip fracture, significant weight loss, and poor intake needs nutritional support to optimise surgical recovery and reduce complications.
Universal malnutrition screening of all adult patients within 24 hours of hospital admission (mandated by ESPEN and Joint Commission accreditation standards)., representing an important application area for the Nutrition Risk Score in professional and analytical contexts where accurate nutrition risk score calculations directly support informed decision-making, strategic planning, and performance optimization
Identifying ICU patients who require early enteral nutrition initiation within 24–48 hours of admission., representing an important application area for the Nutrition Risk Score in professional and analytical contexts where accurate nutrition risk score calculations directly support informed decision-making, strategic planning, and performance optimization
Pre-operative nutritional optimisation: patients with NRS ≥5 benefit from 7–14 days of pre-operative nutritional support before major surgery., representing an important application area for the Nutrition Risk Score in professional and analytical contexts where accurate nutrition risk score calculations directly support informed decision-making, strategic planning, and performance optimization
Cancer treatment: screening oncology patients for malnutrition before each chemotherapy cycle to identify those requiring dietitian-led intervention., representing an important application area for the Nutrition Risk Score in professional and analytical contexts where accurate nutrition risk score calculations directly support informed decision-making, strategic planning, and performance optimization
Quality improvement: using NRS-2002 screening rates and nutritional care plan completion as quality metrics for hospital accreditation., representing an important application area for the Nutrition Risk Score in professional and analytical contexts where accurate nutrition risk score calculations directly support informed decision-making, strategic planning, and performance optimization
Obesity and Malnutrition Paradox
{'title': 'Obesity and Malnutrition Paradox', 'body': "Patients with obesity (BMI >30) can be simultaneously obese and malnourished ('sarcopenic obesity') — high fat mass with low muscle mass and protein-calorie deficiency. The NRS-2002 may underestimate nutritional risk in obese patients because BMI thresholds do not apply. A patient with morbid obesity who has lost 10% of body weight and has reduced food intake may have a normal BMI but significant lean mass loss. Clinical assessment of muscle mass (grip strength, calf circumference) should complement the NRS-2002 in obese patients."}
Inflammatory Bowel Disease
{'title': 'Inflammatory Bowel Disease', 'body': "Patients with active IBD have simultaneously increased metabolic demand (disease severity score 2–3) and nutritional impairment from malabsorption, poor appetite, and dietary restriction. NRS-2002 is well-suited to IBD patients. Exclusive enteral nutrition (EEN) is used therapeutically in paediatric Crohn's disease and pre-operatively in malnourished adults to improve surgical outcomes. Nutritional status should be assessed at every IBD clinic visit."}
Oncology Patients
{'title': 'Oncology Patients', 'body': 'Cancer patients have very high rates of malnutrition — up to 80% in pancreatic and gastric cancer, 40–70% in lung cancer, and 20–30% in haematological malignancies. Malnutrition in cancer is associated with poorer chemotherapy tolerance, reduced treatment efficacy, greater toxicity, and shorter survival. Early nutritional assessment using NRS-2002 (or PG-SGA in oncology) and dietitian-led intervention can improve quality of life and, in some settings, survival outcomes.'}
Critical Care Nutrition
{'title': 'Critical Care Nutrition', 'body': 'ICU patients with NRS-2002 ≥3 (most have scores of 5–7) require early enteral nutrition (within 24–48 hours of admission if haemodynamically stable). The PERMIT trial showed permissive underfeeding (70% of target in the first 7 days) is non-inferior to full feeding for mortality but reduces infections. Current ESPEN critical care guidelines recommend 70–80% of calculated energy targets in the acute phase, rising to full targets in the stable/recovery phase.'}
| Component | Score 0 | Score 1 | Score 2 | Score 3 |
|---|---|---|---|---|
| Nutritional Status | Normal | Mild impairment (>5% loss in 3 mo or intake 50–75%) | Moderate (>5% in 2 mo or BMI 18.5–20.5 or intake 25–50%) | Severe (>5% in 1 mo or BMI <18.5 or intake 0–25%) |
| Disease Severity | Normal | Mild (hip fracture, chronic disease) | Moderate (major surgery, stroke, COPD) | Severe (ICU, head injury, BMT) |
| Age Adjustment | — | — | — | +1 if age ≥70 years |
What is the difference between NRS-2002 and MUST?
NRS-2002 is specifically validated for hospitalised patients and includes a disease severity component, making it suitable for patients with severe acute illness (ICU, post-operative). MUST (Malnutrition Universal Screening Tool) is validated across community, outpatient, and hospital settings and is simpler (3 steps: BMI, unintentional weight loss, acute disease effect). MUST is recommended for community and primary care screening; NRS-2002 is preferred for hospital inpatients. Both identify patients who require nutritional assessment and intervention.
What nutritional support is indicated when NRS ≥3?
Nutritional support is stepped according to clinical need: first, oral nutritional supplements (ONS) — high-calorie and high-protein drinks or fortified foods; second, enteral tube feeding (nasogastric, nasojejunal, or PEG) if oral route is inadequate or unsafe (dysphagia, post-oesophageal surgery); third, parenteral nutrition (PN) if the gastrointestinal tract is non-functional (short bowel syndrome, intestinal failure, post-major GI surgery). Energy target: 25–35 kcal/kg/day; protein target: 1.2–2.0 g/kg/day depending on clinical condition.
Why is age ≥70 given an extra point in NRS-2002?
Older patients have reduced physiological reserve, including reduced muscle mass (sarcopenia), impaired immune function, lower bone density, and reduced capacity to recover from acute illness. Even if their nutritional status and disease severity scores are equivalent to younger patients, older patients have worse outcomes from malnutrition and are more likely to benefit from nutritional support. The 1-point age adjustment reflects this increased vulnerability.
What are the consequences of hospital malnutrition?
Hospital malnutrition — affecting 20–40% of hospitalised patients — is associated with significantly worse outcomes: increased post-operative complications (wound infection, anastomotic leak, pneumonia), prolonged hospital stay (average 5.4 additional days per malnourished patient), higher readmission rates, increased mortality, greater pressure ulcer incidence, and delayed functional recovery. ESPEN estimates that hospital malnutrition costs the EU healthcare system over €100 billion annually.
How often should NRS-2002 be repeated during hospitalisation?
ESPEN recommends rescreening with NRS-2002 every week during hospitalisation in patients who initially score <3, as clinical deterioration can increase nutritional risk over time. Patients who score ≥3 should have a full nutritional assessment by a dietitian and a personalised nutritional care plan, with progress reviewed at least weekly. In rapidly changing clinical situations (e.g., critical care), daily review of nutritional adequacy is appropriate.
What is refeeding syndrome and how is it prevented?
Refeeding syndrome is a potentially life-threatening complication of initiating nutritional support in severely malnourished patients. It is characterised by dangerous falls in serum phosphate, potassium, and magnesium as these electrolytes shift into cells during the anabolic response to refeeding, causing cardiac arrhythmias, respiratory failure, heart failure, and neurological complications. Prevention: identify high-risk patients (BMI <16, negligible food intake for >10 days, significant prior weight loss), check and correct electrolytes before feeding, start at 10 kcal/kg/day and increase slowly over 7 days, supplement thiamine before and during refeeding (100 mg three times daily).
What is the ESPEN recommendation for protein intake in malnourished hospitalised patients?
ESPEN recommends protein intake of 1.2–2.0 g/kg/day for malnourished hospitalised patients, compared to 0.8 g/kg/day for healthy adults. In critically ill patients, ESPEN recommends 1.3 g/kg/day (higher in burns, trauma, ICU). Higher protein intakes (up to 2.5 g/kg/day) may be appropriate in some high-catabolism states. Energy delivery (non-protein calories) should be 25–30 kcal/kg/day in most hospitalised patients, with caloric targets adapted for critically ill patients in the first week of ICU admission.
Can NRS-2002 be used in outpatient settings?
NRS-2002 was specifically developed and validated for hospitalised adult patients. It is not validated for outpatient or community use. MUST (Malnutrition Universal Screening Tool) is validated for community, outpatient, and hospital settings and is recommended by NICE and BAPEN for primary care and nursing home screening. For oncology outpatients, the PG-SGA (Patient-Generated Subjective Global Assessment) is widely used. Always use the tool validated for the specific care setting.
プロのヒント
The preliminary screening step of NRS-2002 (four yes/no questions about BMI <20.5, recent weight loss, recent reduced food intake, and disease severity) can identify low-risk patients in under a minute without needing the full scoring. Only if any preliminary question is positive does the full NRS-2002 score need to be completed. This makes efficient ward-wide malnutrition screening practical for nursing staff.
ご存知でしたか？
Malnutrition in European hospitals was first systematically quantified in the landmark SNAQ study (Short Nutritional Assessment Questionnaire, 2005), which found that 25% of admitted hospital patients were malnourished. A follow-up pan-European study (EuroOOPS, 2008) confirmed this, showing 33% of 5,051 hospitalised patients across 25 countries were at nutritional risk — yet the majority had no nutritional plan documented in their medical record, reflecting how consistently nutrition was underappreciated in hospital medicine.
参考文献
- ›Kondrup J et al — NRS-2002 Development and Validation (Clin Nutr 2003)
- ›ESPEN Guideline on Clinical Nutrition in Hospital (Clin Nutr 2021)
- ›ESPEN Guideline on Critical Care Nutrition (Clin Nutr 2019)
- ›Sorensen J et al — EuroOOPS Malnutrition Study (Clin Nutr 2008)
- ›NICE CG32 — Nutrition Support in Adults (2006 updated 2017)