Geriatrics Flashcards
What is aging?
the process that converts healthy adults into frail older persons with diminished reserves in most physiologic systems and increased vulnerability to most diseases
What are the four major features of aging?
it is:
- destructive
- progressive
- partly determined by genetic code
- and universal
What is usual aging?
- a more step-wise form of aging that involves a gradual, consistent decline towards death
- chronically ill or multimorbid as diseases add up until death
What is successful aging?
aging in which there is preserved function and compression of morbidity (long relatively slow decline that ends in a sharp drop off to death)
At what point in our lives are we all most alike? Least alike and most heterogenous?
at birth we are biologically very similar and our heterogeneity increases with age
What part of a history should follow the review of systems if you are dealing with a geriatric patient? Why?
a review of function because these patients have increasing frailty and vulnerability and an therefore an increased risk of impaired function
What is homeostenosis?
a term used to describe a reduced physiologic reserver and a resulting diminished ability to maintain homeostasis during periods of stress
What five vision changes are common during the aging process?
- decreased dynamic visual acuity
- decreased detection of lateral motion
- decreased depth perception
- decreased contrast sensitivity
- increased glare sensitivity
How do vision changes impact the daily lives and medical care of geriatric patients?
- reduces quality of life
- eliminates the possibility of night driving
- increases risk of falls
- causes medication issues (finding pills, reading labels, etc.)
What is presbycusis? Describe it’s onset.
- the loss of high frequency hearing that occurs with normal aging
- it is slowly progressive, bilateral, and symmetrical
What is presbystasis?
- the “dysequilibrium of aging”
- characterized by vestibular degeneration
- it is a diagnosis of exclusion
What two auditory changes are common during the aging process?
- presbycusis (loss high frequency hearing)
- presbystasis (dysequilibrium of aging)
How do the changes in hearing that accompany aging affect geriatric quality of life?
it contributes to social isolation, loss of self-esteem, depression, anger, and family discord
How do taste and smell change with aging?
the threshold for tasting salty and sweet rise
How does the increased threshold for tasting salty and sweet impact the health of geriatric patients?
- take less pleasure in eating and therefore eat less, contributing to weight loss
- add more salt to their diet, potentially contributing to heart failure or hypertension
Name 6 geriatric changes that contribute to physiologic anorexia of aging?
- reduced physical activity
- diminished metabolism
- reduced stretch of the gastric fundus, resulting in early astral filling
- slowed gastric emptying
- increased circulating CCK
- decrease in dynorphins, which regulate eating drive
How does the esophagus change with aging?
- poor swallowing coordination
- presbyesophagus (low amplitude contractions)
What contributes to reduced swallowing coordination in geriatric populations?
- reduced facial strength
- reduced lingual pressure reserve
- pharyngeal swallow delay
What is presbyesophagus?
an age-related decreased in contractile amplitude within the esophagus
At what age might effective esophageal contractions be absent?
after age 80
Why are esophageal changes an important consideration in geriatric populations?
because they increase the risk of micro aspiration and can contribute to physiologic anorexia of aging
List four gastric changes that are seen over the course of normal aging?
- decreased HCl
- delayed gastric emptying
- reduced intrinsic factor production
- disruption of the gastric mucosal barrier
Why are geriatric patients more at risk for a B12 deficiency?
because they produce less intrinsic factor
What gastric conditions are geriatric patients more likely to have because of changes in their mucosal barrier?
- atrophic gastritis
- peptic ulcer disease
Name 6 micronutrients that geriatric patients have reduced absorption of from the small bowel.
- iron
- zinc
- B12
- folic acid
- lactose
- vitamin D
What contributes to a vitamin D deficiency in aging patients?
- reduced vitamin D receptors in the gut
- less efficient production in the skin
- less exposure to UV light
What changes are commonly seen in the colon/rectum of geriatric patients?
- altered coordination of contractions
- increased compliance
- reduced rectal sensation
- diverticulosis
What colonic changes make diverticulosis more common in geriatric patients?
- decreased tensile strength of bowel wall
- slowed transit through the bowel
- poor coordination of contractions in the bowel
Why do geriatric patients have a lower defecation urge? What problems does this pose?
- increased rectal compliance
- decreased rectal sensation
- may contribute to more frequent constipation
Why are geriatric patients at higher risk for constipation?
- because they have increased rectal compliance and decreased rectal sensation
- as a result a larger stool volume is needed for a defecation urge
- stool frequency declines and stool hardness increases
How do LFTs change with age?
they do not; you still need to work them up if they change
How does bile change in geriatric patients?
they have a predisposition toward cholelithiasis because their bile has a higher lithogenic index
How does liver function change in geriatric populations?
- drug clearance is reduced as the oxidative and P450 pathways are diminished
- less synthesis of vitamin-K dependent clotting factors
Why are benzodiazepines avoided in geriatric patients?
- because their metabolism and clearance is greatly inhibited by the slowed oxidative pathway in the liver, leaving these drugs in the system for a very long time
- additionally there appears to be an increase in receptor sensitivity in geriatric populations
How does the pancreas change during normal aging?
pancreatic exocrine function, absorption of fats, and absorption of carbohydrates is unchanged
Which GI organ remains unchanged with normal aging?
the pancreas
How does the heart change with normal aging?
- systemic vascular resistance increases
- LV diastolic filing is decreased as a result of lower LV compliance and greater thickness
- as such, there is a greater reliance on atrial kick for ventricular filling
- maximal heart rate decreases
- maximal cardiac output decreases
- exercise vasodilation response decreases
How does systemic vascular resistance change with normal aging?
it increases as arterial compliance diminishes
The geriatric heart has a greater reliance on what diastolic action? Why?
- atrial kick
- because the LV is thicker and less compliant, so passive filling is impaired
To what degree does LV filling decline with age?
50% between the ages of 20 and 80
Is systolic or diastolic cardiac functioning changed with geriatric age?
diastolic
Why does cardiac output decline in geriatric patients if systolic function is normally unchanged?
because filling is reduced and therefore so is stroke volume
Why are older adults more susceptible to atrial fibrillation?
because they are more reliant on atrial kick for ventricular filling and atrial fibrillation removes this contribution
Why do geriatric individuals take longer to recover from tachycardia/exertion?
because they have significantly reduced inotropic and chronotropic responses, prolonging recovery afterwards
How do geriatric patients compensate for a diminished chronotropic response to exertion?
they rely more on increases in stroke volume to compensate for reduced maximal heart rate
Do geriatric patients have a greater reserve for stroke volume or heart rate?
stroke volume
Why do geriatric patients have reduced arterial compliance?
because they have a thickened arterial intima due to calcium deposits, altered collagen and elastin, and smooth muscle hypertrophy
Which layer of geriatric arteries is thickened?
the intima
What kind of hypertension is most common amongst geriatric patients? Why is that?
- isolated systolic hypertension
- because it is a result of reduced arterial compliance
Poorly controlled ISH is a risk factor for what three conditions?
- CVA
- MI
- heart failure
Why are geriatric patients more at risk for orthostatic hypotension?
- because they have diminished baroreceptor sensitivity
- they also often have low blood volumes due to low thirst mechanisms or diuretics
- they often have wider pulse pressures as well because of arterial compliance and ISH
By what age do the lungs fully expand only while standing?
by age 65
What age-related changes are seen in pulmonary function?
- reduced chest wall compliance due to cartilage calcification
- reduced muscle strength and cough effort
- reduced mucocilliary clearance
- reduced micro oropharyngeal aspiration
- reduced alveolar surface area and elastic recoil
- poor lung expansion with a dependence on abdominal breathing
Pulmonary changes associated with normal aging increase the risk for what three things?
- atelectasis
- reduced clearance of viruses and bacteria
- pneumonia (aspiration or not)
What lung volume is expanded in geriatric patients? Why?
residual volume because compliance is increased and elastic recoil is decreased
What lung volumes decrease with aging?
- vital capacity
- peak expiratory flow rate
- FEV1
Which part of the lungs are better perfused and ventilated in a geriatric patient?
- upper lung is better ventilated
- lower lung is better perfused
- resulting in a V/Q mismatch
How do blood gases change with normal aging? How does patient sensitivity to these change?
- PaO2 usually decreases but PaCO2 usually does not change with age
- patients become less sensitivity to both hypoxia and hypercapnia
What renal features decline with age?
- number of functioning glomeruli
- renal mass
- creatinine clearance
What is normal creatinine clearance at ages 60 and 90?
- about 90 mL/min in those that are 60 y.o.
- about 60 mL/min in those that are 90 y.o.
How are geriatric drugs dosed?
according to GFR
How do we correct CrCl in geriatric patients?
CrCl = [(140-age) x lean body weight] / (72 x serum creatinine)
multiply by 0.85 if it is a women
estimate LBW as:
- men = 50 + 2.3 x inches over 5 ft
- women = 45.5 + 2.3 x inches over 5 ft
Why is NPO after midnight dangerous for geriatric patients?
because they lose the ability to maximally conserve water in response to water-deprived or hyperosmolar conditions
Why do geriatric patients often have lower blood volume?
- reduced thirst
- less lean mass (impacts TBW)
- reduced renin response to volume depletion
- ANP may be increased, inhibiting aldosterone release
What is the most common endocrine disorder in the elderly?
hypothyroidism
Why are geriatric patients more susceptible to TB?
because with reduced immune response, they can get a reactivation
Geriatric patients have a reduced incidence of what group of diseases?
autoimmune disease
What is a normal height loss during the aging process?
two inches by age 80
What is the critical feature to be aware of when testing deep tendon reflexes in the elderly?
the key is too look for symmetry because some reflexes may be absent due to normal aging
How do neurologic changes affect the way you take a history with geriatric patients?
slowed information processing should mean that you take a history at a slower pace
How does acute mental status change with normal aging?
acute mental status change is never normal
What changes are seen in those with “atrophy consistent with age”?
- enlarged subarachnoid space
- narrower gyri
- wider sulci
- enlarged ventricles
What is considered poly pharmacy?
more than five prescriptions
Which patients are at greater risk of poly pharmacy?
- over 85
- caucasian
- educated
- CrCl less than 50
- BMI less than 20
- insured
Why does absorption of an oral drug change in the elderly?
- slowed gastric emptying
- reduced gastric acid output
- decreased intestinal motility, blood flow, and surface area
What is the net affect of aging on GI absorption of a drug?
there is no significant change in quantity absorbed but the time to onset or peak may be delayed
Why does distribution of a drug change in the elderly?
- they have more body fat but less muscle mass and body water
- they have decreased cardiac output and altered regional blood flow
What is the net affect of aging on drug distribution?
- the volume of distribution of lipid soluble medications increases
- the volume of distribution of water soluble medications decreases
- and changes in Vd affect loading dose and half-life
Why do changes in the volume of distribution of a drug impact other drug parameters in the elderly?
because Vd affects the necessary loading dose and the half-life
What protein binding changes in the elderly affect drug pharmacokinetics?
- they have decreased serum albumin and decreased protein affinity
- there is also an increase in a1-acid glycoprotein
- as a result, many protein-bound drugs have an increased free fraction in the elderly
Which is more significant in the elderly, changes in volume of distribution of plasma protein binding?
in most cases, Vd is more significant
How does hepatic function change with normal aging?
- decreased hepatic mass
- decreased hepatic blood flow
Which liver metabolism pathways are affected by normal aging?
- phase 1 is diminished
- phase 2 is unchanged
- CYP450 activity is unchanged
How do changes in hepatic metabolism of drugs alter our drug selection?
- since phase 1 is impaired, prodrugs are not activated as well
- we try to use drugs that rely only on phase 2 reactions because these have more predictable effects
Which benzodiazepines are preferred in elderly patients? Why?
we prefer temazepam, oxazepam, and lorazepam because these relay only on phase 2 metabolism by the liver, which is relatively unaffected by normal aging
How does renal elimination of drugs change with normal aging?
- there is decreased renal blood flow and tubular secretion
Why can’t serum creatinine be used as a good estimate of GFR in elderly patients?
- because it remains stable while GFR declines
- it remains stable because there is a reduction in muscle mass with age
How do we estimate lean body weight for geriatric patients?
- men = 50 + 2.3 x inches over 5 ft
- women = 45.5 + 2.3 x inches over 5 ft
What consensus was recently formed regarding PO dosing based on renal function?
found 10 meds to be avoided if CrCl is <30mL/min
- chlorpropamide, colchicine, cotrimoxazole, glyburide, meperidine, nitrofurantoin, probenecid, propoxyphene, spironolactone, triamterene
found 8 meds to be used with caution or at lower doses in such patients
- acyclovir, valacyclovir, ranitidine, rimantidine, ciprofloxacin, gabapentin, memantine, amantadine
Which displays more interpersonal variation, geriatric changes in pharmacokinetics or pharmacodynamics?
pharmacokinetics are more consistent and less variable
What three types of pharmacodynamic changes are seen in geriatric patients?
- numbers of receptors (e.g benzodiazepines)
- sensitivity of receptors (e.g. beta-adrenergic receptors)
- counter regulatory mechanisms (e.g. decrease in baroreceptor sensitivity)
How do the pharmacodynamics of warfarin change in geriatric populations?
there is increased sensitivity and a narrower therapeutic index
How do the pharmacodynamics of anticholinergics change in geriatric populations?
there is increased sensitivity
What side effect is more likely in geriatric patients taking antipsychotics?
tardive dyskinesia and parkinsonism
Why are geriatric patients more susceptible to digoxin toxicity?
because they have increased sensitivity of Na/K-ATPase
How are geriatric patients likely to respond to ACE inhibitors compared to younger populations?
because they already have decreased renin and aldosterone levels, they are likely to have a decreased response to ACE inhibitors
What are four categories of medication-related problems?
- untreated indication
- drug interaction
- adverse drug reaction
- improper drug selection
What is meant by the “untreated indication” medication-related problem in the elderly?
often there is a fear of adding one more drug to a growing list in geriatric patients, leading some conditions untreated
What are some common untreated indication examples in the elderly?
- depression in the nursing home
- osteoporosis in the nursing home
- atrial fibrillation/anticoagulation
- hypertension
- MI primary or secondary prevention
- opioids for fear of addiction
What are the START/STOPP criteria?
- a screening tool used to analyze a patients drug list
- START are drugs you may be falling short with by not starting therapy
- STOPP are drugs that may be inappropriate and should be removed
What are some examples of START drugs?
- anti-coagulation with afib
- statin therapy
- vitamin D in those with known OP
What are some examples of STOPP drugs?
- duplicate prescriptions
- loop diuretics for HTN or dependent ankle edema only
- first generation antihistamines
- long-term BZD use
- PPU use for uncomplicated PUD
- long-term NSAID use for mild OA
Which drugs are most likely to have DDIs?
- highly protein bound drugs
- those metabolized by CYP 450
- inducers/inhibitors of CYP
What are the five most common DDIs and their results in the elderly?
mostly cardiovascular/antihypertensive and CNS/psychotropic combinations
- ACE inhibitor + diuretic: hypotension, hyperkalemia
- ACE inhibitor + potassium: hyperkalemia
- anti-arrhythmic + dirutic: electrolyte imbalance, arrhythmia
- BZD + antidepressant: confusion, sedation, falls
- BZD + antipsychotic: confusion, sedation, falls
What are five risk factors for adverse drug reactions in the elderly?
- polypharmacy
- female gender
- small body size
- hepatic/renal insufficiency
- pervious ADRs
If an elderly patient presents with a new symptom, what should be your first consideration?
that it might be a side effect of another drug they are on
What is a prescribing cascade?
the idea that a patient starts a drug and a while later develops an adverse drug effect, which is not recognized as such; instead, the doctor prescribes a different medication, which has it’s own side effect that is treated by a third drug and so on
What are the Beers criteria used for?
- used to improve the care of older adults by reducing their exposure to potentially inappropriate medications
- it is used as a drug-selection tool
The Beers criteria divide drugs into what three groups?
- avoid in older adults regardless of disease
- potentially inappropriate when used in older adults with a specific condition
- used with caution
What are the two major limitations of the Beers criteria?
- assumes medications with high risk of side effects in the elderly actually will cause the ADR in all
- does not address inappropriate use of an appropriate medication
What is the medication appropriateness index?
a set of 10 questions used to review each medication on a patients drug list
What are the limitations of the medication appropriateness index?
- it is time consuming
- it does not fully identify underuse
What questions are asked on the medication appropriateness index?
- is there an indication for the drug
- is the med effective for the condition
- is the dosage correct
- are the directions correct
- are the directions practical
- are there significant DDIs
- are there significant drug-disease interactions
- is there unnecessary therapeutic duplication
- is the duration of therapy acceptable
- is this drug the least expensive compared to others of equal utility
- is the drug being appropriately taken
- are therapeutic endpoints being monitored
- are there possible adverse drug reactions occurring
- List ten PIRX older adults should avoid or use with caution?
- NSAIDs
- digoxin
- certain diabetes drugs
- muscle relaxants
- certain anxiety/insomnia meds
- certain anticholinergics
- meperidone (demerol)
- ORC combination products containing anticholinergics
- antipsychotics
- estrogen
What are the mediators of cellular aging?
DNA damage, replicative senscence, and misfiled proteins
- ROS-mediated DNA damage
- telomere shortening inhibits cellular replication
- defective protein homeostasis leads to misfolding, deposition, and impaired cell functioning
What is the only mechanisms that appears to counteract aging?
the nutrient sensing pathway, which upregulates DNA repair and protein
What is the genetic theory of aging?
sporadic genetic errors, due to ROS or defective DNA repair gradually accumulate with age
What is the cellular senescence theory of aging?
the idea that telomere attrition contributes to cellular aging as set by the Hayflick limit
Which theory of aging is accepted most widely?
cellular senescence
What group of proteins mediate the nutrient sensing pathway that counteracts aging?
altered sirtuin proteins
What is Werner syndrome?
- a syndrome of premature aging associated with defective DNA helicase
- causes rapid accumulation of chromosomal damage that is thought to mimic the injury that normally accumulates during cellular aging
What is replicative senescence?
a terminally non-dividing state arrived at after a normal cell has reached it’s maximum number of divisions
What two mechanisms appear to control replicative senescence?
- telomere attrition
- activation of tumor suppressor genes, particularly those at the CDKN2A locus
What is the physiologic importance of the CDKN2A locus of tumor suppressor genes?
this locus is believed to be up-regulated to mediate replicative senescence in normal cells
How do cancer cells appear to avoid replicative senescence?
they re-express or up-regulate telomerase, to lengthen telomeres and put off attrition
What are the two mechanisms that maintain protein homeostasis?
- chaperones maintain proteins in their correctly folded conformations
- degradation of misfolded proteins by the autophagy-lysosome and ubiquitin-proteasome systems
Is cellular senescence followed by necrosis or apoptosis?
apoptosis
What behavior modification has been shown to prolong lifespan in animal models?
caloric restriction
Sirtuins mediate what effects?
anti-aging by inhibiting metabolic activity, reducing apoptosis, stimulating protein folding, and inhibiting the harmful effects of ROS
How is it thought that caloric restriction prolongs life?
- increasing sirtuins
- reducing IGF-1 activity, which lowers the rate of cell growth and metabolism and reduces cellular damage
What are the seven types of DNA lesions?
- telomere shortening
- base damaage
- adduct formation
- interstrand crosslink
- spindle errors
- double-strand break
- mismatch
What are the “9 mechanisms of aging”?
- primary hallmarks (causes of damage): genomic instability, telomere attrition, epigenetic alteration, and loss of proteostasis
- antagonistic hallmarks (responses to damage): de-regulated nutrient sensing, mitochondria dysfunction, cellular senescence
- integrative hallmarks (culprits of the phenotype): stem cell exhaustion, altered intercellular communication
When running out DNA on a gel, how does that from whole cells, necrotic cells, and apoptotic cells compare?
- whole cells remain near the loading well (large, intact)
- necrotic create a smear pattern as DNA is broken down into randomly sized fragments
- apoptotic create a ladder as DNA is systematically chopped up
What is lipofuscin?
- a pigment found in aged cells that is a product of per oxidation of fatty acids
- thought of as a “wear and tear” pigment
- doesn’t appear to negatively impact cellular function
What is platelet rich plasma? What is it’s clinical benefit and use?
- an injection of the patient’s activated platelets
- theorized that their release of PDGF stimulates repair
- clinical trials don’t support it’s use
What is the central dogma of pathology?
molecular damage leads to cell damage and then to organ dysfunction which presents as a constellation of clinical symptoms that we classify as a disease
Chronic, non-lethal cellular injury leads to what changes?
atrophy, hypertrophy, dysplasia, etc.
