Nutrition and Disease

Question 1

What are the physiological changes associated with age which lead to worsening nutritional status?

Answer 1

• Hormonal
• Immune system
• Mental health
• Dental decline

Question 2

Describe the relationship between muscle strength and life course.

Answer 2

Question 3

What are the factors that cause and worsen muscle quantity and quality?

Answer 3

• Ageing
  
  • ​Age-associated muscle loss
• Disease
  
  • ​Inflammatory conditions (e.g. organ failure, malignancy)
  • Osteoarthritis
  • Neurological disorders
• Inactivity
  
  • ​Sedentary behaviour (e.g. limited mobility or bedrest)
  • Physical inactivity
• Malnutrition
  
  • ​Under-nutrition or malabsorption
  • Medication-related anorexia
  • Over-nutrition/ obesity

Question 4

Describe the relationship between ageing, illness and loss of muscle mass.

Answer 4

Question 5

What are the complications which arise due to loss of muscle quality?

Answer 5

Question 6

What is the definition of sarcopaenia?

Answer 6

Sarcopaenia is a progressive and generalised skeletal muscle disorder that is assocated with increased likelihood of adverse outcomes including falls, fractures, physical disability and mortality.

Question 7

What are the 4 stages of assessing sarcopaenia?

Answer 7

1. Find cases
   
   • SARC-F ≥4 or clinical suspicion
2. Assess
   
   • Low muscle strength - sarcopaenia probable. Assess causes and start intervention.
     
     • Grip strength
     • Chair stand test
3. Make diagnosis
   
   • Low muscle quantity or quality.
     
     • DEXA scan to confirm sarcopaenia.
4. Check severity
   
   • Low physical performance - severe sarcopaenia.

Question 8

What are the clinical conditions which cause malnutrition-associated sarcopaenia and cachexia?

Answer 8

• Cancer
• Sepsis / critical illness
• Neurodegenerative disease
• Chronic kidney disease
• COPD
• Immune disorders

Question 9

What is sarcopaenic obesity?

Answer 9

• Common in the elderly
• Obesity affects the severity of sarcopaenia
• No specific diagnostic criteria
• Low muscle strength

Question 10

What are the metabolic changes in short-term (<72 hour) starvation?

Answer 10

Question 11

What are the metabolic changes in prolonged (>72 hour) starvation?

Answer 11

• The production of ketones from fatty acids, mobilised from the fat stores, spare the musle protein from being used for glucose production and provide the necessary fuel to brain and muscles.
• There is a sharp decrease in insulin production and an increase in glucagon release which stimulates lipolysis. i.e. fatty acids release from the fat cells, and ketogenesis.
• The basal / resting metabolic rate decreases due to decreases in circulating T3 thyroid hormones and glucocorticoids.

Question 12

What is the impact of older age and disease on nutrient status?

Answer 12

Question 13

Describe ageing protein needs vs intake.

Answer 13

Question 14

What are the practical guidelines for optimal dietary protein intake and exercise for older adults >65 years?

Answer 14

• Healthy
  
  • ​At least 1.0-1.2g protein / kg body weight / day
• With acute or chronic illnesses
  
  • ​1.2-1.5g protein / kg body weight / day, and even higher for those with severe illness or injury
• All older adults
  
  • ​Daily physical activity, if possible.
  • Resistance training as part of an overall fitness regimen.