Elderly And Falls Flashcards
What is an adverse drug reaction?
Undesirable effect of a drug beyond its anticipated therapeutic effects occurring during clinical use
What 3 things can ADRs relate to?
Dose
Time-course
Susceptibility
DoTS classification
Describe dose related adverse drug reactions
Above therapeutic range: toxic reaction eg bleeding following too high dose of warfarin. Treat by reducing dose, Prevent by using minimal effective dose
Within therapeutic range: collateral reaction eg drowsiness with antihistamine. May be unavoidable, May not be reduced even by reducing dose (without also reducing desired therapeutic effect)
Below therapeutic range: hypersusceptibility reaction eg penicillin allergy. Avoid by using foreknowledge of patient susceptibility, Permanent avoidance of drug
Describe time course related adverse drug reactions
First dose reactions: eg hypotension after first dose of ACEi. Advice / special precautions may be needed eg take first dose at night while lying down to reduce risk of collapse
Early reactions: eg nitrate-induced headache. Patients become tolerant to these reactions and can continue with treatment, ADR wears off
Intermediate reactions: eg neutropenia due to carbimazole. Reaction occurs within a specific time frame. No reaction has occurred after this time, vigilance can be relaxed
Late reactions: eg bruising due to corticosteroids. Risk of ADR increases with continued or repeated exposure. Need for long-term monitoring and prevention
Withdrawal reactions: eg SSRI antidepressant discontinuation. Slow withdrawal or reduction of dose needed
Delayed reactions: eg carcinogenesis, teratogenesis. Avoid use of drug in patients who are susceptible
Describe susceptibility adverse drug reactions
Genetic susceptibility
Age
Sex
Specific physiological states – e.g. pregnancy
Diseases – e.g. hepatic / renal impairment
Exogenous factors – drugs interactions, diet
What is ageing? And what influences it?
Gradual loss of function of cells and organs with eventual outcome of death
Influenced by genetics, psychology, lifestyle, socioeconomic, environment
Why should we be concerned about ageing and treatment of elderly people?
We’re all getting older so will be caring for lots of older people
Aim to improve quality of life (as well as longevity)
Resource issues for NHS: 65% of benefit expenditure on over 65y
NHS spending on patients >65y nearly double younger households
Average cost of providing hospital and community health services for a person aged ≥85y is around three times greater than for a person aged 65-74y
What are the stages of old age?
65 – 75yrs - retired
75 – 85yrs - lots of emerging conditions and preventative techniques
85y+ - lots of comorbitidies, polypharmacy
What are normal cardiovascular changes seen in ageing?
Cardiac enlargement / left ventricular hypertrophy
Decreased cardiac output (reduced exercise capacity)
Decreased response of heart rate to exercise
Systolic hypertension
Left ventricular failure
What are normal respiratory changes with ageing?
Decreased FEV1/FVC and increased residual volume
Increaed susceptibility to infection
Increased susceptibility to aspiration
What are normal endocrine changes with ageing?
Decreased insulin sensitivity
Decreased thyroid hormone production
What are normal GI changes with ageing?
Increased gastric acid production
Constipation due to decreased motility
What are normal skin and hair changes with ageing?
Dry skin, wrinkles, increased bruising, slower healing (ulcers/sores), Greying hair
What are normal Genito urinary changes with ageing?
Decreased glomerular filtration rate
Benign prostatic enlargement (prostatism)
Deceased sexual function, erectile dysfunction
Vaginal dryness, increased susceptibility UTI
What are normal musculoskeletal changes with ageing?
Sarcopenia – decreased muscle strength/power
Decreased mobility
Increased likelihood of falls
Increased susceptibility to fractures (osteoporosis)
What are normal nervous system changes with ageing?
Slower thought processes/reactions
Vision deteriorates (presbyopia, cataracts)
High-frequency hearing loss (presbyacusis)
Inner ear dysfunction, balance problems
What are normal immune changes that occur with ageing?
Atrophy of thymus
Decreased immune function - increaed infections, increased cancer, reactivation of latent infections (TB, shingles)
What factors are affected which exacerbate decline when ageing and disease are present together?
Functional capacity Quality of life Independence Wellbeing Care needs Mobility
What physiological changes may lead to increased adverse drug reactions in the elderly?
Receptor responses – e.g. Decreased ß-adrenoceptor sensitivity Altered coagulation factor synthesis CNS becomes more sensitive to psychotropics /hypnotics Baroreceptor response less sensitive Renal clearance reduced Thirst response blunted Thermoregulation blunted Altered immune response Slower gastric emptying Reduced plasma albumin Increased ratio of adipose to lean tissue Altered liver metabolism
What factors may lead to increased adverse drug reactions in the elderly?
Decreased organ function: altered pharmacodynamics, pharmacokinetics and homeostatic functions
Multi disease morbidities
Polypharmacy
Decreased compliance