Elderly care Flashcards
(50 cards)
What do NICE guidelines recommend for dealing with multimorbidity in elderly?
e.g. 78yo with 5 conditions who smokes minimum 11 drugs (+/- 10) minimum 9 self care/lifestyle activities *8-10 routine primary care appts *4-6 medical *8-30 psychosocial intervention *smoking cessation *pulmonary rehab
= seeing HCP probably every week!
what is polypharmacy and link to elderly?
prescribing >4 drugs.
common due to multiple comorbidities
no drugs strongly associated with age. increase
risk of DDI and ADRs increased
Pharmacokinetic factors: absorption. how is it different in elderly?
Reduced:
- saliva (solid oral formulations)
- GI motility- delayed gastric emptying
- GI and regional blood supply
Increased:
- GI pH
BUT little evidence to change dosage because of this. consider formulations still
what can even minor reductions in first pass metabolism lead to?
= significant increase in drug bioavailability.
explained:
first pass metab = extensive metabolism of lipid soluble drugs (90-95%)
reduced hepatic blood flow = reduced first pass metabolism and greater drug effect.
Give 3 examples of drugs that may accumulate (high bioavailability) as a result of reduced hepatic blood flow
Reduced hepatic blood flow = reduced first-pass metabolism in the liver = increased drug bioavailability. accumulate and can have ADRs.
- Nifedipine
- Nitrates
- Verapamil
PK factors: Distribution.
How is it altered in the elderly and what effect does it have?
elderly have altered distribution of body fat and water
more fat, less water
How does increased proportion of fat in eldely affect distribution of lipid soluble drugs e.g. diazepam?
more fat (14-35%) = higher Vd of lipid soluble drugs = accumulate.
How does decreased proportion of water in elderly affect the distribution of water soluble drugs e.g. digoxin?
Less water = decreased Vd for water soluble drugs = lower doses can be required.
e.g. loading doses of digoxin
PK factors: Distribution
affect of change in plasma protein conc in elderly? example of a drug affected
Reduced plasma protein conc/binding = increase in free drug e.g. phenytoin
= increased risk of toxicity!
PK factors- how is overall hepatic metabolism of many drugs changed with age?
and how does change in clearance affect on action of drugs e.g. morphine
overall hep metabolism of many drugs through CYP450 enzyme system decreases with age.
reduced metabolic clearance (30-40%) = higher levels/ duration of action of drugs extensively metabolised (morphine)
affect of reduced metabolic clearance on pro-drugs
= pro drugs may be less effective, as converted in active form by liver
PK factors: Elimination
how does GFR and renal tubular function change with age and which 4 drugs will need dose adjustment as a result?
both decrease (chronic liver disease- low GFR)
Renally excreted drugs need dose adjustment:
- Digoxin
- Gentamicin
- Lithium salts
- Opiates
higher dose: metab and elimination factors
what 5 physio and pathophysiological aspects are also affected by the ageing process?
- Heart
- Endocrine changes
- Skeletal muscle: atrophy
- Bones and joints: osteoporosis and osteoarthritis
- CNS: vision and hearing.
how is heart function changed with age? (4)
- cardiac architecture, less compliance
- loss of pacemaker cells
- calcification of conduction system
- less response to cetecholamines… Ca channel blockers
what endocrine changes are seen with increased age?
Reduced hormone production, target sensitivity
Oestrogen, testosterone, GH, IGF-1
How are receptors affected? (2)
and affect on drugs?
- changes in receptor sensitivity
- reduced numbers of receptors
= increased sensitivity to several drugs
e.g.
how does reduced baroceptor function lead to increased risk of falls?
reduced baroceptor function = increased hypotension with antihypertensive therapy = fall risk
Effect of decreased dopamine receptors
= increased risk of extra pyramidal side effects (EPSE)
- parkisonism
- rigid limbs
- tremor
what 2 things does the effect of age on drug sensitivity vary with however?
- drugs studied
- response measured
e.g. anticoagulation- elderly = greater response to same plasma conc of warfarin than younger patients. mechanism unknown
7 important drugs/classes in older adult patients
- analgesics (opioids, NSAIDs)
- digoxin
- diuretics
- warfarin and other anticoagulants
- ACEis
- beta blockers
- benzodiazepines
- phenothiazines
- antiparkinsonian drugs
affect of frailty on elderly
organ systems progressively declining = loss of function and physiological reserve, increased vulnerability to disease and death.
the primary users of healthcare resources
how is frailty assessed? i.e. quantified
frailty assessment:
1 –> 7
very fit–> severly frail. completely dependant
Five frailty syndromes (Geriatric Giants). any one of these = suspicion of frailty
- falls e.g collapse, found lying on floor
- immobility e.g. sudden change in mobility
- delirium: acute confusion
- incontinence- change/ new onset
- susceptible to side effects of meds e..g confusion w codeine, hypotension with antidepressants
4 ways to minimise risk of falls- major cause of disability and mortality in elderly
- identify drugs causing falls
- review meds-polypharmacy
- nutrition: Ca, Vit D to reduce risks of osteoporosis
- multidisciplinary falls service
