LC 3.4 - Ageing and Endocrine System

Question 1

Describe the general overall effect of ageing on endocrine glands?

Answer 1

The glands suffer some degree of atrophy and fibrosis initiating a decreased rate of hormone secretion, however generally circulating hormone levels remain constant through decreased metabolic breakdown

Question 2

Describe the general overall effect of ageing on the HPA axis?

Answer 2

Progressive loss of sensitivity to feedback control

Question 3

What effect does ageing have on the hormone Triiodothyronine (T3)?

Answer 3

Remains unchanged/decreases

Question 4

What effect does ageing have on the hormone testosterone (free)?

Answer 4

Decreases

Question 5

What effect does ageing have on the hormone insulin?

Answer 5

Remains unchanged/decreases

Question 6

What effect does ageing have on the hormone cortisol?

Answer 6

Increases

Question 7

What effect does ageing have on the hormone parathyroid hormone?

Answer 7

Increases

Question 8

What effect does ageing have on the hormone norepinepherine?

Answer 8

Increases

Question 9

What effect does ageing have on growth hormone?

Answer 9

Decreases

Question 10

What effect does ageing have on the hormone dihydroepiandosterone?

Answer 10

Decreases

Question 11

What effect does ageing have on the hormone oestrogen?

Answer 11

Decreases

Question 12

What effect does ageing have on the hormone FSH/LH?

Answer 12

Increases

Question 13

What effects does ageing have on the Thyroid gland?

Answer 13

Altered T3/T4 secretion and blunted TSH (Ant pituitary) in response to TRH (hypothalamus), however MOST changes occur by illness and medication

Question 14

Name the percentage declines of T3 and T4 levels in healthy elderly individuals?

Answer 14

T3 - 30% decrease

T4 - 25% decrease

Question 15

Describe the symptoms typically present with hypothyroidism?

Answer 15

Fatigue
Weakness (myalgia)
Dry skin
Bradycardia
Weight gain

Question 16

How is hypothyroidism diagnosed in patients?

Answer 16

High levels of TSH

Low levels of T4 (free)

Question 17

What are the main causes of hypothyroidism?

Answer 17

Autoimmune (Hashimoto’s)
Neck surgery
Radiation

Question 18

Describe the symptoms typically present with hyperthyroidism?

Answer 18

Confusion
Atrial fibrilation
Weight loss
XS sweating

Question 19

What are the main causes of hyperthyroidism?

Answer 19

Grave’s disease

Toxic multinodular goitre

Question 20

Where is growth hormone synthesised and released?

Answer 20

Anterior pituitary

Question 21

What molecule is stimulated by growth hormone?

Answer 21

IGF-1

Question 22

What is the relationship between growth hormone and fat metabolism?

Answer 22

Decreased growth hormone levels leads to increased fat accumulation

Question 23

Falls in the levels of which two hormones may cause growth hormone levels to decrease as a result?

Answer 23

Testosterone/oestrogen

Question 24

As ageing leads to decreasing growth hormone what is the significance of this?

Answer 24

Increased body fat (100%)
Decreased muscle mass (20-50%)
Decreased bone mass (20%)

Question 25

What effect does ageing have on cortisol levels and what is the significance?

Answer 25

Increased cortisol levels during the night (normal in the mornings) Cortisol has anti-insulin effects

Question 26

How is hypertension linked to ageing?

Answer 26

Ageing causes decreased responsiveness to glucocorticoid feedback, this in turn leads to increased glucocorticoid levels which causes XS aldosterone production and hence blood pressure increases

Question 27

What effect does ageing have on glucocorticoid levels and what is the significance?

Answer 27

Increases Increased blood pressure Increased free-radical formation - Increased cellular damage