Normal BMI, visible oedema, and a malnutrition question
A 72-year-old woman with COPD is referred for malnutrition risk after a hospital admission for pneumonia. Her weight has fallen from 68 kg to 60 kg over 6 months. Height is 1.62 m (BMI 22.9 kg/m²). She has bilateral ankle oedema and a distended abdomen; the medical team notes possible heart failure. She lives alone, eats one small meal daily, and reports early satiety and fatigue. Albumin is 28 g/L, CRP 18 mg/L, handgrip strength 16 kg, mid-upper-arm circumference 24 cm, and calf circumference 28 cm. MNA-SF score is 8. She has smoked 20 pack-years and uses a rollator. The team asks whether she is malnourished and what energy and protein targets to use. A nurse suggests using current weight for calculations because 'BMI is normal'.
1. Does this patient meet criteria for malnutrition? Show your reasoning, including why BMI alone is misleading here.
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She meets malnutrition criteria despite a normal BMI. Using GLIM, at least one phenotypic criterion and one aetiologic criterion are required. Phenotypic: unintentional weight loss of 8 kg in 6 months is 11.8% of her usual 68 kg, exceeding the >5% threshold; calf circumference 28 cm and handgrip 16 kg also suggest reduced muscle mass and strength. Aetiologic: reduced food intake (one small meal daily, early satiety) and inflammation (CRP 18 mg/L) are both present. BMI 22.9 kg/m² does not exclude malnutrition because oedema and ascites inflate weight and BMI; the current weight is not a valid lean-tissue measure. Albumin is not a specific malnutrition marker and is depressed by inflammation, so it should not be used alone to diagnose or exclude malnutrition. The MNA-SF score of 8 also flags risk. The correct judgement is to treat this as malnutrition with likely fluid overload, not to reassure the team because BMI is 'normal'. Document the usual weight, weight trajectory, intake, and functional indicators, and request medical review of the oedema and heart failure status.
2. Which body weight would you use to set energy and protein targets, and what ranges would you calculate?
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Do not use the oedematous current weight of 60 kg as if it were lean or dry weight. Use the pre-illness weight of 68 kg as the best available reference, or a documented dry weight if the team can provide one. For an older adult with COPD and malnutrition, start conservatively at 25–30 kcal/kg/day: 25 × 68 = 1,700 kcal/day; 30 × 68 = 2,040 kcal/day. Start nearer 25 kcal/kg because she is malnourished and at risk of refeeding; advance according to tolerance and electrolyte monitoring. Protein should be 1.2–1.5 g/kg/day using the same reference weight: 1.2 × 68 = 82 g/day; 1.5 × 68 = 102 g/day. If the team insists on current weight, the numbers would be 1,500–1,800 kcal and 72–90 g protein, but that would under-prescribe energy and protein while overestimating lean mass. Explain the assumption explicitly in the record, and reassess after diuresis if dry weight changes.
3. What additional assessment and monitoring would you prioritise before finalising the nutrition plan?
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Prioritise: (1) a 24-hour or 3-day food and fluid recall, including protein sources, portion sizes, and use of salt or supplements; (2) swallow and dentition screen, because early satiety and fatigue may reflect dysphagia, poor dentition, or depression; (3) biochemistry relevant to refeeding - phosphate, potassium, magnesium, sodium, and renal function - before and during feeding; (4) functional and psychosocial assessment, including mobility, cooking ability, income, and social support, since she lives alone; (5) clarification of heart failure fluid and sodium advice so the nutrition plan does not conflict with medical management. Monitor weight at a consistent time with attention to oedema, intake adequacy, handgrip or sit-to-stand function, and electrolytes. Use a food-first approach with small, energy- and protein-dense meals and oral nutritional supplements only if intake remains below targets. Reassess in 1–2 weeks and revise the diagnosis and targets if dry weight or clinical status changes.