Wk.1 L1 - Human Physiology Changes Throughout the Lifespan Flashcards
LO
- Describe key contributors to increased human lifespan and our ageing population
- Outline key components of human health which define lifespan specific to:
* Cardiovascular system
* Musculoskeletal system
* Nervous system - Explain differences between male vs female in chronic disease risk and life
expectancy - Recall why non-human models are used to explore lifespan in research
Life expectancy
In 1800’s it was 40, now its 70
- In Australia its ~84
- Causes a shift in population proportions (lower rated of reproduction and increased life expectancy)
Increased due to advances in:
Standard of living and public health
- Nutrition, clean water, sanitation, economic growth, poverty reduced & health education
Medicine
- Peri,post and neonatal healthcare
- Antibiotics, vaccines, pharma, surgeries and device technology
Age related deteriation
Brain
Heart
Musculoskeletal
Lungs
Gastrointestinal
Brain aging
- Brain volume increases during development and reduces ~3% per decade during mid-late life
- In late life ventricular volume increases as grey matter decreases
- Dementia has a correlation with increased age & higher in females
Cardiovascular aging
Cardiac tissue and function:
- Walls lose strength and elasticity
- Hypertrophy of muscle cells & fibrosis
Heart Rate:
- Max HR. declines with age (mHR = 220-age)
Sinoatrial node:
- Function declines with age
Reduced vascular integrity:
- Atherosclerotic plaques form
- Arteries increase stiffness due to fibrosis
These factors increase CVD and death rates in late life.
Musculoskeletal Aging
Bone Density:
- Bone mineral density changes with age (peaking at 30)
- Loss of trabecular structure leading to fractures
Joints:
- Thinner and less resilient
- Ligaments and tendons become ridgid, affecting ROM
- Leading to gait and posture problems
Muscle mass:
- Peaks at 30 then declines
- Decreases with age
- Leading to gait and posture problems
Male and female disparities in age changes
Peak Bone Mass:
- Different peaks and decline rates between genders
Muscle Mass:
- Relates to puberty, causing peaks to be very different
- Peak sizes are very different, causing women to fall into disability earlier but lose muscle at a slower and steadier rate
Vascular changes:
- males develop CVD integrity changes with age earlier than females
Brain changes:
- Ealier decline in females than males
Females live longer lives as they are more robust to mortality at every age. (NOT aging slower)
Modelling lifespan research
C. Elegans work well as they live for 2-3 weeks
LO summary
heft / canvas
