Physiological changes associated with ageing

Question 1

What are the physiological changes associated with ageing?

Answer 1

• Decrease in glomerular filtration rate= - Drug clearance is less efficient
• Reduction in liver enzymes
• Changes in fat composition - fat greater than muscle mass
• Creatinine synthesis reduced
• Volume of drug distribution changes (based on drug type)
• Changes in ROS determined by calories
• Vestibular system becomes impaired with age
• hearing loss
• Slower processing speeds —> can lead to memory loss

Question 2

Which factors contribute to the physiological changes associated with ageing?

Answer 2

-1. Diet
- Calorific restriction is associated w/ higher survival in mice
- Fasting increases ROS which increases longevity by activation of SIRT3
2. Sleep
3. UV exposure
4. Activity and exercise
5. Smoking
6. Stress
7. Fluids

—> these are influenced by socio-economic background, ethnicity, geographical location

Question 3

What are the effects of these changes in terms of older people’s healthcare needs?

Answer 3

• Age affects drug half-life
• Drug metabolism declines
• Drug sensitivity is altered - can have different effects on patients symptoms
• Prescribing & deprescribing need to be monitored w/ age to prevent toxicity - regular reviews
• More care & support needed

Comorbidities and chronic illnesses = greater potential for drug interactions
- e.g. - Alzheimer’s diseas, Arthritis, Asthma, Cancer, COPD, Diabetes

Question 4

How do these changes relate to disease burden in society?

Answer 4

1. More time spent reviewing medications
   - Consider: deprescribing/reviewing during hospital admissions or diagnosis of new conditions
2. Potential drug interactions or drug errors due to polypharmacy (difficult to keep track) = more hospital admissions/mortality
3. Ageing population so patient number is overall increasing bc older people are more likely to present w/ disease = more resources, hospital beds, drugs etc

Question 5

What causes us to age biologically?

Answer 5

• Mutations building up in DNA
• Teleomere shortening - due to abscence of teleomerase in somatic cells. Cell division stops once telemeres get too short.
• Damage to mitochondria