Prescribing in Older People

These flashcards cover key concepts and terms related to the prescribing practices for older adults, emphasizing pharmacokinetic changes, frailty assessment, medication safety, and clinical guidelines.

Pharmacokinetics

The study of how drugs are absorbed, distributed, metabolized, and excreted by the body.

Frailty

A clinical syndrome characterized by reduced reserve and resistance to stressors, resulting from cumulative declines across multiple physiological systems.

Clinical Frailty Scale

A tool used to assess the frailty level of individuals, ranging from 'Very Fit' to 'Terminally Ill'.

Polypharmacy

The concurrent use of multiple medications by a patient, often seen in older populations.

Adverse Drug Events (ADEs)

Harmful effects resulting from the use of a drug, which can lead to emergency department visits, especially in older patients.

CYP Enzymes

Cytochrome P450 enzymes involved in the metabolism of drugs, which can be affected by age and health status.

Deprescribing

The process of tapering or stopping medications that may no longer be necessary or beneficial to a patient.

Beers Criteria

A list of medications that are potentially inappropriate for older adults due to the high risk of adverse effects.

START/STOPP Criteria

Tools used to optimize the pharmacotherapy of older patients by identifying potentially inappropriate prescriptions or opportunities for appropriate treatment.

Metformin

A common medication used to treat type 2 diabetes that is contraindicated in patients with significant renal impairment.

"Define chronological ageing."

"Age based purely on time alive (years lived) commonly using a cutoff such as 65 years."

"What is biological ageing?"

"Age based on physiological reserve health organ function and vulnerability rather than years lived."

"What is frailty?"

"A clinical syndrome involving reduced physiological reserve weakness slow walking speed exhaustion and increased vulnerability to stressors."

"What happens to gastric emptying in older adults?"

"It slows (delayed gastric emptying) increasing time drugs spend in the stomach."

"What protective stomach factor decreases with age?"

"Gastric mucus production and effectiveness."

"What effect does delayed gastric emptying have on NSAIDs?"

"Increases local gastric irritation dyspepsia and bleeding risk."

"What protein decreases with age that affects drug binding?"

"Serum albumin."

"What happens to highly protein-bound drugs when albumin decreases?"

"Higher free (active) drug concentration → increased toxicity risk."

"What type of NSAIDs are most affected by protein binding changes?"

"Highly protein-bound ones such as naproxen warfarin aspirin."

"What happens to liver blood flow in ageing?"

"It decreases reducing phase I metabolism capacity."

"What phase of metabolism is most affected by ageing?"

"Phase I (CYP450) metabolism."

"What happens to renal function with age?"

"GFR progressively declines reducing clearance of renally-excreted drugs."

"How is metformin eliminated?"

"100% renally excreted unchanged."

"What risk increases when metformin accumulates?"

"Lactic acidosis."

"What are the NICE renal cut-offs for metformin?"

"Review dose if eGFR

"What is polypharmacy?"

"The use of multiple medications often defined as ≥5 but hyper-polypharmacy is >10."

"What contributes to polypharmacy growth?"

"Guideline-driven prescribing prescribing cascades multi-morbidity."

"What is a prescribing cascade?"

"When a drug causes a side effect and another drug is prescribed to treat that side effect."

"What is the Clinical Frailty Scale?"

"A 1–9 scale assessing severity of frailty based on dependence ,comorbidity and resilience."

"What does a Clinical Frailty Score of 7 mean?"

"Severely frail—completely dependent for personal care but stable."

"Why are older adults more susceptible to adverse drug events (ADEs)?"

Reduced metabolism, reduced excretion, increased free drug, frailty, polypharmacy."

"In the case, how many medicines was the older patient taking?"

17 medications daily

"Which medicines in the list increase fall risk?"

"Diazepam atenolol amlodipine bendroflumethiazide amitriptyline."

"Which listed drug has a narrow therapeutic index?"

"Digoxin."

"What GI bleed risk does an NSAID pose for someone ≥75?"

"1 in 110 chance of GI bleed per year."

"What is the mortality risk from NSAID-related GI bleed in ≥75?"

"1 in 647."

"What did the naproxen binding graph show?"

"Older adults have higher unbound naproxen concentrations than young adults."

"What percentage of older-adult admissions were taking benzodiazepines in the cohort study?"

"30.3%."

"What is the conclusion about long-acting benzodiazepines?"

"They significantly increase fall and hospitalisation risk."

"How much lower was metformin clearance in the elderly?"

"35–40% lower."

"How much lower was metformin clearance in moderate–severe renal impairment?"

"74–78% lower."

"What update year of Beers Criteria is shown?"

"2023."

"What does STOPP stand for?"

"Screening Tool of Older Persons' Prescriptions."

"What does START stand for?"

"Screening Tool to Alert doctors to Right Treatment."

"What is the purpose of STOPP/START?"

"STOPP identifies inappropriate drugs; START identifies important omissions in older people."

"What is a statin’s typical time-to-benefit in older adults?"

"Around 3 years."

"What decision-making model was shown for life expectancy?"

"Walter & Covinsky’s framework."

"What four-quadrant model was used for end-of-life prescribing?"

"Holmes et al.’s medication appropriateness model."

"What important idea is emphasised about prescribing tools?"

"Tools guide decisions but do not replace individualised patient-centred judgement."

"Define NNT."

"Number needed to treat—how many people must take a drug to prevent one adverse outcome."

"Define NNH."

"Number needed to harm—how many people must take a drug for one person to experience harm."

"What is the NNT for preventing a non-fatal MI with statins (primary prevention)?"

"104 people."

"What is the NNT for preventing a non-fatal MI with statins (secondary prevention)?"

"39 people."

"What side effect of statins is most common?"

"Muscle toxicity."

"How many people need to take statins for one case of muscle toxicity?"

"1 in 10 (approx.)."

"What is the main downside of PPIs used with NSAIDs long-term?"

"Associated with ↑ fracture risk ↓ magnesium, ↑ infections

"What is the recommended approach for NSAID prescribing in older adults?"

"Use lowest effective dose + PPI + reassess need frequently."

"Which benzodiazepine is preferred in older adults?"

"Oxazepam (shorter-acting no active metabolites)."

"Why is diazepam inappropriate for older adults?"

"Long half-life active metabolites needs Phase I metabolism accumulates."

"What are examples of START criteria drugs?"

"ACE inhibitors in heart failure bisphosphonates in osteoporosis statins in established CVD (secondary)."

"What are examples of STOPP criteria drugs?"

"Long-term benzodiazepines NSAIDs in renal impairment, duplicate drug classes

"What is the main concept behind shared decision-making?"

"Balancing benefits vs. harms in context of patient values and life expectancy."

"Name four age-related pharmacokinetic changes."

"↓ gastric emptying ↓ albumin ↓ CYP metabolism↓ renal excretion."

"Why are active metabolites a problem in older adults?"

"They prolong drug effect and accumulate due to slower metabolism."

"In the prescribing cascade example

which drug initially caused fluid retention?"

"What did amlodipine cause in the cascade example?"

"Ankle swelling (oedema)."

"What did furosemide cause in the cascade example?"

"Postural hypotension/dizziness."

"What did betahistine cause in the cascade example?"

"Dyspepsia."

"What drug was added to manage dyspepsia?"

"Gaviscon."

"Which STOPP category includes long-term PPIs?"

"STOPP Section A: potentially inappropriate PPIs beyond recommended duration."

"What common antihistamines are inappropriate in older adults per Beers?"

"Chlorphenamine diphenhydramine (strong anticholinergic burden)."

"What class of drugs increases risk of Clostridioides difficile when combined with PPIs?"

"Broad-spectrum antibiotics."

"What prescribing issue does the lecture say medics often miss?"

"Recognising prescribing cascades."

"What is a key limitation of NICE guidelines for older adults?"

"They focus on single diseases rather than multimorbidity."

"How does frailty affect recovery from illness?"

"Frailer adults have reduced ability to recover from physiological stress (infection hospitalisation)."

"What is one clinical sign of frailty?"

"Slow walking speed."

"What is another sign of frailty?"

"Unintentional weight loss."

"What is a functional sign of frailty?"

"Difficulty with activities of daily living (shopping, self-care

"What is a pharmacodynamic change seen in ageing?"

"Reduced receptor sensitivity or receptor number (e.g. β-receptors)."

"What does reduced β-receptor sensitivity mean clinically?"

"Reduced response to β-agonists (e.g. salbutamol)."

"What is a prescribing cascade?"

"When a drug causes a side effect that is misinterpreted as a new condition leading to another drug being prescribed to treat that side effect."

"Describe the full prescribing cascade example involving naproxen."

"1) Naproxen prescribed → causes fluid retention and hypertension. 2) Amlodipine added for hypertension → causes ankle oedema. 3) Furosemide added to treat oedema → causes dizziness/postural hypotension. 4) Betahistine added for dizziness → causes dyspepsia. 5) Gaviscon added for dyspepsia."

"Why are prescribing cascades dangerous in older adults?"

"They increase polypharmacy worsen adverse effects raise fall and hospitalisation risk and treat drug side effects instead of the underlying cause."