Physiology-Geriatrics

Question 1

Most rapidly growing segment of society

Answer 1

80-85. For the 1st time in history the elderly outnumber kids

Question 2

How does health relate to age as patients get older and older?

Answer 2

Health becomes more and more heterogeneous. Note that you can’t relate medical disability to ability to function independently

Question 3

Compression of Morbidity Hypothesis

Answer 3

By postponing development and age-related diseases, disability can be compressed into the last few years of life and life expectancy is typically fixed.

Question 4

What is a common factor seen in many centenarians?

Answer 4

They maintain cognitive function well into their 9th decade and maintain independent functionality.

Question 5

3 paths to extreme longevity (centenarian)

Answer 5

1) Survivor (43%): avoids disability despite developing common age-associated disease 2) Delayers (42%): develop age-associated diseases much later 3) Escapers (15%): avoid age-associated diseases until the final stages of life (fulfilling the compression of morbidity hypothesis)

Question 6

Why some elderly patients won’t receive a knee replacement

Answer 6

Dissuaded by surgeon because of long list of comorbidities, even though they can live a long time despite the comorbidities

Question 7

What contributes to development of disease as people age?

Answer 7

Genetic, lifestyle and environmental factors account for disease, typically it is not the normal aging process

Question 8

Cardiac changes with aging

Answer 8

Diminished early diastolic filling (more prone to CHF from loss of atrial kick), increased pulse wave velocity (stiffening of blood vessels), myocardial hypertrophy, decreased compliance of blood vessels (increased pulse pressure = S4), ischemia from low diastolic pressure.

Question 9

Renal changes with aging

Answer 9

Renal atrophy (loss of mass & glomeruli), diminished GFR, increased post-void residual urine and decreased renal blood flow.

Question 10

Pulmonary changes with aging

Answer 10

Diminished ciliary clearance (increased infections), decreased respiratory muscle strength, impaired cough reflexed, diminished respiratory response to hypoxemia and hypercapnea

Question 11

CNS changes with aging

Answer 11

Changes in psychomotor speed, memory, cerebral atrophy (could be normal), diminished PNS conduction velocity, decreased fine motor control

Question 12

MSK changes with aging

Answer 12

Loss of muscle mass, OA, degenerative changes in bones and discs, decreased metabolic rate (increased fat: muscle)

Question 13

Neurologic changes with aging

Answer 13

Limited up gaze, slow saccades, diminished Achilles reflex, stooped posture and Parkinsonian findings.

Question 14

Integument changes with aging

Answer 14

Senile purpura, xerosis, benign skin lesions (cherry angiomata, seborrheic keratosis, actinic keratosis)

Question 15

Gradual compression of reserve in various physiologic systems

Answer 15

Homeostenosis: increasing susceptibility to disease due to stressors, diminished reserve and increased weakness. This is very important to consider when working up a patient or giving an elderly patient medications with side effects that may cause stress to these weakened systems.

Question 16

Weakest links in the elderly physiologic system?

Answer 16

Brain (delirium), GU (incontinence) and MSK (falls, poor mobility). This is thought because these systems rely on widely distributed neurologic networks.

Question 17

What is a critical concept to remember when an elderly patient is being worked up?

Answer 17

Sometimes evaluations of the “weak links” (brain, GU, MSK) can be detrimental to the patients health and the work up should be limited to the most pertinent presentation (pneumonia instead of dementia). Contrast this to evaluating a younger person with CNS abnormalities where you would always do a full work up

Question 18

Concurrent presence of 2+ medically diagnosed diseases in the same individual

Answer 18

Comorbidity (2/3 of people 65+ have 2+ chronic conditions)

Question 19

Difficulty or dependency carrying out activities essential to independent living and desired activities

Answer 19

Disability

Question 20

A state of increased vulnerability to poor resolution of homeostasis after a stressor (poor physiologic reserve). Characterized by low muscle mass, weight loss, weakness, fatigue, exhaustion, poor gait speed, balance deficits and cognitive impairment.

Answer 20

Frailty.

Question 21

Acute alteration of consciousness and cognitive function characterized by inattention, disturbed psychomotor activity, perceptual disturbances and altered circadian rhythm? How common is this?

Answer 21

Delirium, affects 1/3-1/2 of hospitalized elderly patients, but 70% of cases go undetected. Often a sign of potentially life-threatening illness (pneumonia, abdominal infection etc)

Question 22

An acquired syndrome of cognitive decline typically involving memory and at least one other cognitive domain of sufficient severity to impair everyday function? How common is this?

Answer 22

Dementia, affects 1/3 of people by age 80. Often not diagnosed until later stages because patient/family members see cognitive decline as a normal process of aging.

Question 23

What things might also improve if a patient improved from delirium/dementia?

Answer 23

Mobility (more steady and less falling) and GU (diminished incontinence). These are the “weak links”. Conversely, these abilities will decline together.

Question 24

Why might medical decisions be difficult for a physician treating the oldest of the old?

Answer 24

There is very little evidence based medicine in this population. This is because these patients often have comorbidities that exclude them from clinical trials. Polypharmacy, shifting priorities and clinical guidelines also make treatment difficult.