Learning question: can you describe effects on these three body systems?

Title: Effects of aging on skeletal, cardiovascular and respiratory systems

Homework: You have your class test next week – study!

19 April 2023

Learning ObjectivesCandidates should be able to:

(f) describe the effects of ageing on the skeletal system, with reference to osteoarthritis and osteoporosis;

(g) outline methods of preventing osteoporosis (reference should be made to calcium, vitamin D, HRT and exercise) (HSW6a,7c);

(h) describe the use of bone density tests in the detection of osteoporosis;

(i) describe the effects of ageing on the cardiovascular and respiratory systems;

Key words•Osteoblast•Osteoclast•Intervertebral discs

•Osteoarthritis

•Emphysema•Bronchitis•Pneumonia•Aterosclerosis

•Atherosclerosis

•Angina•Myocardial infarction

•Sinoatrial node

Effects of aging on the skeletal system• Bone mass starts to reduce

between the age of 30 and 40 years.

• Osteoblast (cells that make bone) activity declines but osteoclast (bone cell that resorbs bone tissue) activity continues at normal levels

• Bones break more easily and do not repair well

Effects of aging on the skeletal system

• Vertebrae may collapse leading to “Dowager’s hump”

• Intervertebral discs shrink – compressed discs and loss of bone mass lead to decrease in body height

• Incidence of osteoarthritis increases

• Osteoporosis – bones affected are less dense than normal bone so fracture are more likely

Osteoarthritis (OA)

• Becomes more common with increasing age

• Most cases develop in over 50s – at least 50% of over 65s gave sine degree of OA

• 1 in 10 over 65s have a major disability linked to OA (mainly hip and knee)

• Causes pain, stiffness and limitations to movement of joints. Stiffness usually worse in the morning but tends to “loosen up”

Osteoarthritis (OA)• Water content of cartilage increases with age, and glycoprotein make-up

of cartilage decreases

• Repetitive use of joints over time causes irritation, inflaming joints and causes swelling.

• Cartilage begins to degenerate by flaking and tiny crevasses form

• Advanced cases: total loss of cartilage cushion between bones – loss of joint mobility

• Inflamed cartilage can also lead to new bone growth called spurs that form around joints– Hips, knees, fingers, thumb and lower spine are commonly affected joints

Why do some people develop OA?

• Evidence suggests that if joints are used earlier in life e.g. sports, this may have an effect– Knee joint OA is common

• Possible genetic link– OA occasionally found in multiple members of families

• Hip and knee OA more likely to be more severe in obese people

• Ethinc links to hip OA in white Europeans than African or Asian populations

Treatment for OA

• Paracetamol– Effective to manage pain, if taken regularly instead of when pain

arises

• Anti-inflammatory painkillers– Not used as often as paracetamol due to side effects, especially in

older people– Can be taken for 1-2 weeks then return to paracetamol

• Hip and knee replacements– Very successful and can restore mobility

Osteoporosis

• In childhood, bones grow and repair very quickly, but this process slows as you get older.

• Bones stop growing in length between the ages of 16 and 18, but continue to increase in density until you are in your late 20s.

• From about the age of 35, you gradually lose bone density. This is a normal part of ageing, but for some people it can lead to osteoporosis and an increased risk of fractures.

• http://www.nhs.uk/Conditions/Osteoporosis/Pages/Introduction.aspx

How can osteoporosis be prevented?

• It is important to build up bone mass from childhood onwards by:– Drinking milk or eat milk-based products so have sufficient

calcium and vitamin D– Exercise is good, particularly weight-bearing exercise– Do not smoke and avoid excessive intake of alcohol– Check home safety to prevent falls– Post-menopausal women may need to replace oestrogen

by taking HRT– Long-term use of some medications can lead to a loss of

bone density

How can osteoporosis be detected?

• “DEXA” scan – the best method of detection, DEXA scans use X-rays to determine the density of bone

• Ultrasound of the heel bone is also used to determine bone density. It uses cheaper equipment, but is not yet clear if it is accurate or reliable as DEXA scanning

Respiratory system and aging• Lungs become less elastic – less effective

• Rib cage may not move freely due to arthritis

• Overall reduction in chest movement, limiting respiratory volume

• Normally sufficient in healthy individuals, but becomes a problem if infection sets in

• Severe respiratory disorders more common in elderly e.g. emphysema, tuberculosis, pneumonia and bronchitis

• Pneumonia – often a complication of influenza; vaccination for ‘flu is offered annually to patients aged 65 and over; pneumococcal vaccine is also offered

Cardiovascular system and aging• Cardiovascular diseases are major causes of death in the UK

in men over 45 years and women over 65 years of age

Cardiovascular system and agingOrgan What happens? Causing? Result

Arteries Artery walls become less elastic. May show signs of calcification.

Fatty deposits, e.g. cholesterol, in artery wall

Arterosclerosis – hardening of the arteries

Artherosclerosis

Loss of elasticity and lessened blood flow

Increase in blood pressure

Normal blood flow obstructed, shortage of oxygen-carrying blood at cells.

Could result in a stroke

Organ What happens? Causing? ResultHeart Exercise – cardiac output

reduces Response of heart is slower and less forcible

Coronary arteries narrow

Hypertension – LV works harderHeart valves become thickened and more rigidNumber of pacemaker cells die

Cannot pump blood efficiently

Exertion/sudden movement – decreases in CO

Blood supply to cardiac muscle is restricted

Ventricle may enlarge and become weaker

MurmursSinoatrial node beats more slowly

Circulation is slowedDizziness and loss of balance

Angina, myocardial infarction (MI)

Heart less able to alter its rate

Questions1. State 4 effects of aging on the skeletal system

2. Distinguish between osteoarthritis and osteoporosis

3. Why do people appear to shrink as they get older?

4. What can be done to help in the prevention of osteoporosis?

5. State two effects of aging on our respiratory system

6. Distinguish between arterosclerosis and artherosclerosis

7. What causes angina?