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Flashcards in The Ageing Endocrine Systems Deck (43)
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1
Q

What is meant by ‘compression of morbidity’?

A

Popular with geriatricians - aim is that illness and disability squeezed into a short period at the end of life

2
Q

What is the endocrine system?

A

Made up of organs + tissues that produce hormones

3
Q

What is a hormone?

A
  • A chemical messenger
  • Released into the bloodstream from one location to target other organs or tissues
  • Amino acid or steroid based
4
Q

How does the hypothalamus link the nervous system to the endocrine system?

A

Via the pituitary gland

5
Q

Where is the central circadian clock located in the hypothalamus?

A

Suprachiasmatic nucleus

6
Q

What changes occur as a result of the ageing hypothalamus?

A
  • Circadian rhythm diminishes with age
  • Decreased sleep + disturbed sleep/wake cycle
  • Diminished appetite
  • Poor thermoregulation
7
Q

Is it the posterior or anterior pituitary that produces its own hormones?

A

Anterior pituitary produces its own hormones. Posterior pituitary stores hormones made in the hypothalamus.

8
Q

mnemonic: GOAT FLAP

Which hormones does the pituitary gland produce? Which of these two are produced by the posterior pituitary?

A
  • Growth hormone (GH)
  • Oxytocin
  • Anti-diuretic hormone (ADH)
  • Thyroid stimulating hormone (TSH)
  • Follicle stimulating hormone (FSH)
  • Luteinising hormone (LH)
  • Adrenocorticotropic hormone (ACTH)
  • Prolactin
9
Q

What is growth hormone also known as?

A

Somatotropin

10
Q

What is the action of growth hormone?

A
  • Causes production of IGF-1 from liver
  • Involved in protein, fat + carbohydrate metabolism (gluconeogenesis, muscle growth, bone growth)
11
Q

What happens to growth hormone levels with age?

A
  • Growth hormone decreases with age
  • GH secretion from pituitary declines progressively after puberty -> decreased levels of IGF-1
  • Decreased muscle mass + bone density
  • Somatopause
12
Q

What are advantages of replacing growth hormone?

A
  • Increased lean body mass
  • Decreased adipose tissue
  • Increased bone density
13
Q

What are limitations of replacing growth hormones?

A
  • Has to be given subcutaenously
  • Difficult dosing
  • Side effects - hyperglycaemia, oedema, arthralgia
  • Increased IGF-1 can increase malignancy
  • Cost
14
Q

Which is the active hormone released from the thyroid?

A

T3 - causes most of the metabolic effects

(T4 is a peripheral storage of thyroxin and just gets converted to T3)

15
Q

What changes occur regards to the thyroid gland with age?

A
  • TSH increases
  • T4 levels remain unchanged
  • Increased levels of thyroid antibodies (autoimmune)
  • Both hyperthyroidism and hypothyroidism more prevalent - many undiagnosed
16
Q

What is sick euthyroid syndrome and what is it caused by?

A
  • Abnormal TFTs in patients unwell with non-thyroid systemic disease
  • Caused by:
  • > reduced TSH secretion
  • > lower thyroid hormone binding
  • > reduced peripheral T4 -> T3 (so T4 remains normal)
  • These^ reverse once underlying illness improves
17
Q

What are clinical features of hypothyroidism?

A
  • Hearing loss
  • Psychosis, depression, coma
  • Loss of outer eyebrows + dry, brittle hair
  • Thick, coarse features
  • Goitre, hoarse voice
  • Congestive cardiac failure, bradycardia, hypertension
  • Slow reflexes, myalgia, carpel tunnel
  • Ataxia, anorexia, overweight, constipation, menorrhagia
  • Cold intolerance
  • Oedema
18
Q

What are clinical features of hyperthyroidism?

A
  • Restlessness, malaise, irritability, psychosis
  • Goitre, bruit
  • Opthalmoplegia, exopthalmos
  • Periorbital oedema
  • Heat intolerance
  • Tachycardia, AF, hypertension, CCF, SoB
  • Tremor, palor, erythema, onycholysis
  • Thirst, weight loss, poor appetite, d&v
  • Proximal myopathy, pretibial myxoedma
19
Q

What is the visible difference between exophthalmos and proptosis?

A
  • Exophthalmos = eye protruding from orbit (can see white above AND below pupil)
  • Proptosis = eye bulging out, can cause chemosis
20
Q

Why is thyroid disease tricky to detect in the elderly?

A
  • Symptoms are non-specific and often mistaken for the ‘normal ageing’ process
  • Examination is difficult as thyroid may be shrunken + kyphotic posture
  • Overlapping presentation of hypo- + hyper-thyroidism in elderly (confusion, depression, incontinence etc)
21
Q

What does the adrenal cortex produce?

A
  • Aldosterone
  • Cortisol
22
Q

What does the adrenal medulla produce?

A

Catecholamines (adrenaline + noradrenaline)

23
Q

What happens to adrenal function with age (specifically cortisol)?

A
  • Cortisol is the stress hormone
  • Levels increase with age
  • Diurnal variation in cortisol is altered in elderly
  • Chornically elevated levels have been implicated with numerous age-related conditions eg. cog impairment, CVD
24
Q

What is menopause and when does it occur?

A
  • Cessation of menstruation due to ovarian failure
  • 45-55
25
Q

What hormone changes occur post-menopause?

A
  • Oestrogen levels fall
  • FSH and LH increase initially + then fall
26
Q

What are the immediate post-menopausal symptoms?

A
  • Hot flushes
  • Insomnia
  • Altered mood
  • Atrophy of oestrogen responsive tissue
27
Q

What are the long term symptoms/impacts of menopause?

A
  • Increased cardiovascular risk
  • Rapid loss of skeletal mass + bone mass
  • Vasomotor instability
  • Psychological symptoms
  • Loss of libido
28
Q

When should hormone replacement therapy be used?

A
  • menopausal symptoms where the risk:benefit ratio is favourable
  • For women with early menopause
29
Q

What are the benefits of HRT?

A
  • Improve vasomotor symptoms
  • Reduction in osteoporosis
  • Improve sleep + mood
  • Reduce risk of colorectal cancer
  • Reduce risk of cardiovascular disease
30
Q

What are risks of HRT?

A
  • Small inc risk of breast, ovarian + endometrial cancer
  • Increased risk of venous thromboembolism
  • Increased risk of stroke
  • Increased risk of cholecystitis
  • Side effects eg. bloating, breakthrough bleeding, breast tenderness
31
Q

What are non-HRT options?

A
  • Atrophic vaginitis - use topical oestrogens
  • Clonidine (a-stimulant) may reduce hot flushes (though can inc BP)
32
Q

What happens to gonadal function in ageing men?

A
  • Testosterone levels decrease w age
  • Decreased libido
  • Reduced muscle strength + bone mineral density
33
Q

Should we replace testosterone in the elderly?

A
  • Consider for patients w symptoms of hypogonadism and/or markedly reduced levels of testosterone
  • Can improve bone mineral density, muscle mass, libido, mood etc
  • BUT REMEMBER, contraindicated in prostate cancer, increased risk of heart disease
34
Q

What changes occur with glucose metabolism in ageing?

A
  • Beta cell function declines
  • Glucose-induced insulin release is delayed + smaller
  • Peripheral insulin resistance increases
  • —-> increased impaired glucose tolerance + progression to T2DM
35
Q

What are secondary causes of diabetes mellitus?

A
  • Steroids
  • Thiazides
  • Pancreatitis
  • Cushings disease
  • Hyperthyroidism
36
Q

Diabetes mellitus is difficult to diagnose in the elderly due to symptoms sometimes being related to ‘ageing’, what are these symptoms?

A
  • Glucosuria + polyuria occur later
  • Impaired thirst (polydipsia occurs later)
  • Presentation: coma, delirium, thrush, cellulitis, weight loss, urinary incontinence, general malaise, vascular disease, peripheral neuropathy
37
Q

What are microvascular complications of diabetes?

A
  • Diabetic retinopathy
  • Diabetic nephropathy
  • Diabetic neuropathy
38
Q

What are macrovascular complications of diabetes?

A
  • Stroke
  • Heart disease
  • Peripheral vascular disease
39
Q

What are limitations to treating diabetes in the elderly?

A
  • Risk of drug-induced hypoglycaemia, confusion falls + fractures
  • LT benefits of treatment unknown in frail or >80
  • Practical difficulties with administering insulin
  • Full compliance with dietary change or insulin not always possible
  • Dietary change could cause loss of QoL
40
Q

What changes occur in regards to parathyroid gland function and associated hormones, with age?

A
  • PTH rises with age
  • Reduced sunlight exposure
  • Post menopausal reduced hydroxylation of Vit D
  • Reduced effect of PTH (altho counterbalanced by PTH rise)
  • Diminished capacity of skin to convert cholesterol to Vit D
41
Q

Ageing leads to a decrease in overall bone mineral density, leading to which disease?

A

Osteoporosis

42
Q

Summary Q: Which 2 hormones increase with age?

A
  • Cortisol
  • PTH
  • (TSH gradually does)

The rest decrease and T4 remains unchanged

43
Q

What are easy, cheap yet important tests used to screen in the elderly?

A
  • TFTs
  • Vit D
  • Ca
  • Haematinics (iron, b12, folate)