1. The Physiology & Pathology of Aging
Chapter 3
The Physiology & Pathology of Aging

2. Objectives:
Compare & contrast the concepts of aging as a “disease” & aging as a “process”.
Compare & contrast preventive medicine & curative medicine.
Describe the theories of biological aging.

3. Aging
Culture not only influences personal perspectives & family living arrangements but also the way that scientists approach aging and death.
Western medicine, with its greater emphasis on curative rather than preventive medicine.

4. Paola S. Timiras Disease Aging Selective process Universal process
Intrinsic & extrinsic
May progress or regress
Occasionally deleterious
Treatable and has a known cause
Aging
Universal process
Intrinsic
Progressive
Deleterious (harmful)
Irreversible

5. Average life expectancy in the United States:
Has risen from 45 years in 1900 to 76 years in 1990: attributed to what?
Yet during this period, there has been no change in the maximum life span potential
(the oldest age reached by an individual in a population) of Americans, est. to be about 115.
Improvements in sanitation, food, water. Now have antibiotics and vaccinations.

6. Chronic Disease of Aging- Can be modified by behavior changes: p.50
Condition Prevention
Hypertension
Atherosclerotic cardiovascular disease
Cancers
COPD
Diabetes Mellitus(II)
Osteoporosis
Osteoarthritis
Choleithiasis
Reduce Sodium & body weight
Treatment of hypertension
Stop smoking
Reduction of dietary fat
Minimization of sun exposure.
Avoidance of alcohol

7. Theories of Biological Aging
Molecular & Evolutionary Theories of Aging
Cellular Theories of Aging
Free-Radical Theory of Aging
Cross-Linking & Glycosylation Theories of Aging
Research has not yet discovered the “fountain of youth”. Aging is very complex as there is no true biological marker of aging.

8. Age-Related Changes of the Organ Systems:
Integumentary System
Because skin covers our entire body, it is more noticeable than other age-related changes.
It begins to flatten, becomes thin and wrinkling.
As skin thins out it becomes vulnerable to abrasions and blisters, and normal wear and tear.

9. Integumentary System
Chronic exposure to sunlight is the biggest source of aging skin.
Responsible for wrinkling, yellowing, coarseness, & irregular pigmentation of skin with advancing years.

10. Skin Cancer Malignant melanoma Basal cell carcinoma
Squamous cell carcinoma
Basal cell & Squamous comprise more than 50 % of all malignancies in the U.S.
Elderly are particularly prone to develop skin cancer.

11. Nervous System
The nervous system must be intact for proper functioning of all the other systems.
Because of its complexity, it is the least understood.
Yet, central nervous system disorders are the most common cause of disability in the elderly.

12. Normal / Abnormal memory loss with aging
Alzheimer’s
The most common form of dementia.
As the disease progresses, all of the deficits of dementia worsen.
Patients usually regress developmentally, displaying some behaviors similar to infants.
Dementia
Mental deterioration in orientation, memory, intellect, judgment and emotional status
Two thirds of all nursing home patients suffer from dementia
Mild loss of memory for recent events is quite common, while long term memory remains intact.

13. Special Senses: Vision Hearing Taste Smell Vision: Hearing: Taste:

14. Sleep

15. Musculoskeletal System
Skeletal muscle undergoes changes as we age.
Osteoporosis: the reduction in bone mass & bone density-condition predisposes an individual to fractures,-vertebras-femur-distal radius.
Osteoarthritis: degenerative joint disease-second most common cause of disability in the U.S.-affecting >50 million Americans.

16. Cardiovascular System
Postural Hypotension: a fall in systemic blood pressure upon rising from a supine to a standing position. Causes lightheadedness when a person stands up & can thus increase the risk of falling.
Atherosclerosis: development of fatty plaques & the proliferation of connective tissue in the walls of arteries-can lead to blockage of the artery.

17. Cardiovascular -continued
Aneurysms--destruction of the inner layers of the artery wall can weaken it & cause it to balloon out under the force of blood pressure.
Breaks in the fibrous capsule of fatty plaques can cause ulcerations, leaving the underlying fat deposits exposed to the bloodstream, which clump & form clots or thrombus.

18. Atherosclerosis
Development of fatty plaques and the proliferation of connective tissue in the walls of the arteries.

19. Respiratory System:
Chronic obstructive pulmonary disease (COPD), & lung cancer (caused primarily by cigarette smoking)
Steps leading to emphysema begin when cigarette smoke irritates the respiratory tract, stimulating proliferation of white blood cells called macrophages.
Chronic bronchitis-common in elderly- those with a long history of cigarette smoking.

20. Hematological System High prevalence of anemia.
Pernicious anemia - Vitamin B-12.
Red cells are many times decreased.

21. Immune System:
Infections
Cancer
Autoimmune disease

22. Genitourinary & Endocrine Systems:
Kidneys & bladder
Pituitary Gland
Thyroid Gland
Adrenal Gland
Testes & Ovaries

23. Summary:
While there may be wisdom in the adage, “live for the day”, it is equally wise, from a health perspective, to “live for tomorrow”.
“A word to the wise is sufficient!”