Neuro of Aging

Question 1

cognitive: intelligence, performance IQ, verbal IQ

Answer 1

• intelligence peaks in young adulthood
• performance IQ: declines more than 40% b/c of decline in motor skills not as much b/c of actual intelligence decline
• verbal IQ: stable prior to age 60; up to 10% loss through 8th decade

Question 2

cognitive: speed of central processing and learning

Answer 2

• speed of central processing gradually and continually declines from 3rd through 8th decade
• impaired learning related to recent memory impairment

Question 3

impaired vision

Answer 3

• decline in contrast sensitivity (shades) and VA (presbyopia)
• increasing lens and vitreous opacification
• lens becomes more rigid = impaired accommodation
• pupil becomes smaller and less reactive

Question 4

restricted vertical eye movements

Answer 4

• young adults have 35-45 degrees of upgaze
• adults in 8th decade have only 15-20 degrees of upgaze
• limited neck motion: decrease in upgaze happens more b/c of disuse v. actual degeneration of the vertical gaze

Question 5

presbycusis

Answer 5

• elevation of auditory threshold, especially for higher frequencies
• difficulty w/ speech discrimination
• degeneration of hair cells in organ of Corti

Question 6

motor system changes

Answer 6

• decreased m. mass, strength and speed
• anterior horn cell degeneration
• mild decline in coordination

Question 7

sensory system changes

Answer 7

• decreased vibratory sensation in legs
• only feeling vibrations in UE is a normal finding in the elderly
• position sense should be intact everywhere

Question 8

reflex changes

Answer 8

• generally reflexes are depressed
• depressed reflexes is a normal elderly finding but absent reflexes is not - absence indicates some underlying issue
• could be due to loss of large fiber function

Question 9

gait changes

Answer 9

• postural righting reflexes are preserved but increased postural sway
• stable gait relies on sensory input, motor response and integration of both –> remember Romberg’s test and its implications

Question 10

frontal release signs

Answer 10

• the frontal lobe suppresses these reflexes as children develop and they can return in the elderly
  1. palmomental refles: stroke palm and + if you see chin flinch; 20-27% in 20-50yo; 20-60% in 60-93yo
  2. snout reflex: tongue blade over lips and tap - pt will purse lips in response; 13% v. 54% >60yo
  3. suck reflex: rarely seen even in elderly - more pathologic; only 5% in >65yo
  4. grasp reflex: very rare in normal population; most pathologic

Question 11

peripheral neuropathy

Answer 11

• normal changes in the elderly do not produce:
  1. + symptoms (paresthesias) or
  2. significant - symptoms (weakness)

Question 12

orthostatic hypotension

Answer 12

• decreased baroreceptor sensitivity
• blunted increase in heart rate
• reduction in response to pressor drugs
• tendency for volume depletion (nutritional deficits and medications can be cause)

Question 13

hypothermia

Answer 13

• defined as core temp <35 degrees C
• decreased ability to maintain thermal homeostasis
• impaired heat conservation: less fat and decreased vasoconstriction
• impaired heat production: decreased metabolic rate

Question 14

hyperthermia

Answer 14

• defined as core temp >41C or >40.7C w/ anhidrosis or altered mental status
• impaired heat loss b/c of inadequate sweating and reduced peripheral vasodilation

Question 15

sleep disturbances

Answer 15

• elderly require less sleep –> only 5-6h
• decreased sleep duration, frequent arousals, early awakening, frequent napping, reduction of Stage IV and REM sleep
• evaluation includes enforced sleep cycle, assess for sleep apnea and be cautious w/ use of sleeping pills (can contribute to falls)

Question 16

Falls: epidemiology

Answer 16

• 30% of people 65+ fall each year
• accidents (includes falls) = 6th leading cause of death
• falls can result in fx, serious soft tissue injuries, joint dislocations, closed head injuries
• 1% of falls cause hip fx and 20% of these people die in 6 months

Question 17

falls: etiology

Answer 17

1. cognitive: dementia can cause apraxia, normal pressure hydrocephalus, multi-infarct; dementia is treatable not curable
2. sensory: vision (cataract, macular degeneration, glaucoma), auditory, vestibular (drugs, trauma, previous surgery, vertigo), proprioception (neuropathy, myelopathy, spinal stenosis)
3. motor: stroke, spinal stenosis, myelopathy, Parkinson ds
4. continence

Question 18

falls: consequences

Answer 18

• result in injury, pain, restricted activity, anxiety, fear, depression, loss of confidence
• the more falls = higher chance for nursing home placement

Question 19

falls: prevention methods

Answer 19

1. assess meds: pts w/ 4+ meds at higher risk; in particular benzodiazepines, sedatives and antidepressants are high risk b/c they dull sensations and slow rxn times
2. assess home; check footwear, lighting, stairs, flooring, wires, clutter, bathroom
3. assess diet: calcium & vitamin D, bone density, folate/B12, alcohol use
4. assess physical well-being: strengthening, exercise and ROM programs (tai chi, weights, resistance training, flexibility); balance programs
5. assess mental well-being: psychological support, mini-mental status eval