Malnutrition Adults and the Elderly

Malnutrition is a state of nutrition in which a deficiency, excess, or imbalance of energy, protein, and/or other nutrients leads to measurable adverse effects on tissue/body form, function, and clinical outcome. It includes both undernutrition (e.g., wasting, stunting, micronutrient deficiencies) and overnutrition (e.g., obesity, metabolic syndrome).

• 🔽 Undernutrition: Insufficient intake or absorption of nutrients → weight loss, muscle wasting, immune dysfunction.
• 🔼 Overnutrition: Excess calorie/nutrient intake → obesity, diabetes, cardiovascular disease.
• ⚖️ Imbalance: Micronutrient deficiencies or disproportionate macronutrient intake despite normal/raised weight.

💡 Teaching Pearl

In clinical practice (UK), malnutrition usually refers to undernutrition, especially in hospital and elderly patients, and is often identified using screening tools such as the MUST score. Think of malnutrition as a spectrum — not just "too little food," but any imbalance that harms health and recovery.

🔍 Investigations in Malnutrition

Investigations should be tailored to the suspected underlying cause of malnutrition. They help assess nutritional status, detect deficiencies, and identify contributory medical conditions.

• 📊 Baseline Blood Tests (all suspected cases):
  • FBC: Anaemia (iron, folate, B12 deficiency), infection, chronic disease.
  • U&E, Creatinine: Renal function, electrolyte imbalances.
  • LFTs, Albumin: Chronic liver disease, protein status (note: albumin is not a sensitive malnutrition marker).
  • CRP/ESR: Chronic inflammation driving catabolism.
  • Glucose/HbA1c: Diabetes or hypoglycaemia risk.
• 🦴 Micronutrient & Endocrine Tests (if clinically indicated):
  • Iron studies & Ferritin: Suspected anaemia of deficiency or chronic disease.
  • Vitamin B12 & Folate: Macrocytic anaemia, neurological symptoms.
  • Vitamin D & Calcium: Bone pain, falls risk, osteopenia/osteoporosis.
  • Magnesium & Phosphate: Risk of refeeding syndrome.
  • Thyroid function tests (TFTs): Exclude hypo/hyperthyroidism as a contributor.
  • Cortisol (AM): Suspected adrenal insufficiency.
• 🍽️ Nutritional Assessment Tools:
  • MUST (Malnutrition Universal Screening Tool): Recommended in all hospital/community settings.
  • BMI & Weight Trend: Key for tracking progress.
  • Dietary history/food diary: Assesses caloric/protein intake.
• 🩻 Imaging (selected cases):
  • CXR: Chronic lung disease, TB, malignancy.
  • Abdominal USS/CT: Malignancy, chronic liver disease, bowel pathology.
  • DEXA scan: Assess bone density in chronic malnutrition/osteoporosis risk.
• 🧪 Specialised Tests (if unclear cause):
  • Coeliac screen (tTG, IgA): Chronic diarrhoea, weight loss, iron deficiency.
  • HIV/Hepatitis serology: If unexplained weight loss, chronic infection risk.
  • Stool studies: Malabsorption (faecal elastase for pancreatic insufficiency, stool fat).

💡 Teaching Pearl

Start with basic bloods (FBC, U&E, LFTs, glucose) in every patient. Escalate to micronutrient assays, coeliac screen, imaging only if the history or examination suggests an underlying condition. 👉 Always consider refeeding risk: check phosphate, magnesium, potassium before initiating nutrition.

🍂 Causes of Malnutrition in Adults & the Elderly

• 🧠 Physiological Changes:
  • 🍽️ Reduced Appetite: Altered hunger/satiety signals with age.
  • 👃 Reduced Taste & Smell: Food less appealing → ↓ intake.
  • 🥣 Digestive Problems: Dysphagia, constipation, achlorhydria, or delayed gastric emptying.
  • 🦷 Dental Issues: Poor dentition or ill-fitting dentures limit food choices.
• ❤️ Chronic Illness:
  • 🩺 Chronic Disease Burden: Diabetes, COPD, CKD, cancer increase metabolic demand & reduce appetite.
  • 💭 Mental Health: Depression, anxiety, dementia, delirium reduce desire or ability to eat.
  • 🔥 Inflammatory States: Sepsis, chronic wounds, autoimmune disease increase catabolism.
• 💊 Medication-Related:
  • ⚡ Appetite Suppression: e.g., SSRIs, opioids, digoxin.
  • 🤢 GI Side Effects: Nausea, diarrhoea, taste changes from chemo, antibiotics, metformin.
  • 🥦 Nutrient Interactions: PPIs (↓ B12, Mg), diuretics (↓ K, Mg), anticonvulsants (↓ Vit D).
• 👥 Social Factors:
  • 🏠 Isolation & Loneliness: Eating alone reduces motivation.
  • 💰 Financial Barriers: Poverty, food insecurity, difficulty accessing shops.
  • 🧑‍⚕️ Neglect or Elder Abuse: At home or in institutions.
• 🦯 Functional Limitations:
  • 🚶 Mobility Issues: Frailty, arthritis, stroke limit shopping & cooking.
  • 🍳 Cooking Barriers: Cognitive decline, visual impairment, weakness.
• 🏥 Hospital & Iatrogenic Causes:
  • 🚫 NBM Status: Prolonged “nil by mouth” during admission.
  • 🧪 Frequent Investigations: Missed meals for scans/tests.
  • 🏨 Institutional Food: Unpalatable or inappropriate hospital meals.

🌟 Management of Malnutrition in the Elderly

• 📊 Screening & Monitoring:
  • 📝 MUST Tool (Malnutrition Universal Screening Tool) at hospital/community level.
  • ⚖️ Track Weight & BMI: Monitor for unintentional weight loss.
  • 🧪 Labs: Albumin, pre-albumin, micronutrient assays if suspected deficiencies.
• 🥗 Nutritional Interventions:
  • 🍲 High-Calorie, High-Protein Diet: Frequent small meals, fortified foods.
  • 🥛 Oral Nutritional Supplements (ONS): e.g., Ensure, Fortisip.
  • 💧 Hydration: Encourage fluids, especially in dementia patients.
  • 🥦 Micronutrients: Vit D, Ca, iron, B12 replacement as needed.
• 🩺 Medical & Therapeutic Support:
  • ⚕️ Optimise Chronic Illness: Treat CHF, COPD, malignancy, depression.
  • 💊 Medication Review: Stop appetite-suppressing or GI-irritating drugs where possible.
  • 🥄 Feeding Interventions: Texture-modified diets for dysphagia, speech & language therapy referral.
• 🍴 Feeding Assistance:
  • 📋 Meal Planning: Easy-to-prepare, enjoyable foods.
  • 🤲 Assisted Feeding: Carers/nurses, adaptive cutlery.
• 💬 Psychosocial Support:
  • 👨‍👩‍👧‍👦 Group Meals: Lunch clubs, day centres, “meals with company.”
  • 🧑‍⚕️ Mental Health Support: Counselling, antidepressants, memory clinics.
• 📚 Education & Training:
  • 👩‍⚕️ Caregiver Training: Meal prep, feeding assistance, nutrition basics.
  • 🙋 Self-Management: Cooking classes, community dietitian input.
• 🏘️ Community & Social Services:
  • 🍱 Meal Delivery: “Meals on Wheels” or volunteer services.
  • 🚗 Transport Aid: Community schemes for shopping & appointments.
  • 🏡 Home Adaptations: Equipment for safe, independent food prep.
• 🚑 Escalation:
  • 🥤 Enteral Feeding: NG/PEG if oral intake inadequate.
  • 💉 Parenteral Nutrition: Last resort for severe malabsorption or GI failure.

💡 Teaching Pearl

Malnutrition in the elderly is multifactorial: physiological decline, social isolation, chronic disease, and iatrogenic factors all contribute. 👉 Early recognition (MUST), proactive nutrition, and holistic care reduce morbidity, hospital admissions, and mortality.