Some common prescribing issues

1. Some common prescribing issues John Gladman Professor of the Medicine of Older People Consultant Geriatrician Community geriatrician for Nottingham North and East

2. Preventative drugs in older people with frailty • NNT and NNH ill understood even in the fit. Most people taking antihypertensive treatment do not benefit (NNT 125 over 5 years for a vascular death). NNH 10 for stopping the drug. • Many preventative treatments have never been tested in older people with frailty such as AHTs in dementia: the NNT could be very large or infinite. NNH might be lower. • Many older people with frailty do not have a long life expectancy for benefits to accumulate (NNT of 125 over 5 years is 62 over 10 years, 31 over 20 years, but 600 over one year) • Many older people with frailty might not agree to take these drugs if they knew how uncertain and how miniscule the “benefits” might be and how frequent the harms are • Many doctors might be more reluctant to promote them and have a lower threshold to advise withdrawing them if they also appreciated this

3. Anaemia • Don’t assume anaemia is iron deficiency and give iron automatically. Iron is often horrid. • Ferritin (<100 is probably iron deficiency, despite the cited reference range), or iron studies if there is inflammation • Only treat if confirmed • Treat to replace for 3 months, and do not automatically keep on for ever • Investigation should always be considered, but aspirin (even at 75mg/day) is a very common factor & stopping it is a reasonable conservative measure • Remember iron transfusions (day case) for iron intolerance are possible • Renal anaemia is common in the frail (true GFR overestimated by eGFR): erythropoietin is used.

4. Anticoagulation in atrial fibrillation- one of the most effective preventative treatments • Aspirin does not reduce the specific thromboembolic stroke risk. It has a small effect on vascular disease in general. It is only very marginally safer than warfarin. It is not an alternative. In AF, the question is anticoagulation. • NNT 25 to prevent a stroke and 42 to prevent a death over 1.5 years. NNT falls in the very old, and with heart failure (e.g. NNT 10 over a year). These strokes are usually game changers. • NNH 25 for bleeding (not game changers), 327 for ICH • NOT contraindications: age, falls • Contraindications: bleeding, poor compliance, end of life • NOACs are OK, but offer no advantage in contraindications • Warfarin is better when compliance is suspect: you can check • Don’t use anticoagulation and anti-platelets: bleeding risk

5. Loop diuretics • Don’t use for swollen ankles: make a diagnosis • BNP is useful to detect heart failure in primary care (less so in acute hospital settings) • Apart for gravitational oedema, often missed diagnoses include renal failure (overestimated eGFR), and hypoalbuminaema • If the diagnosis is heart failure, aim to switch over to diuretic sparing drugs (ACE-I or betablockers) • Gravitational oedema responds to mobilisation, compression and elevation, not intravascular volume depletion. Often these simple treatments are overlooked yet harmful drugs are used • Don’t use loop diuretics for hypertension • Antihypertensive diuretics are a misnomer: indapamide and bendroflumethiazide 2.5mg od have no diuretic properties – they are vasodilators. Loop diuretics are not • Loop diuretics only cause hypotension by excessive volume depletion (i.e. when used poorly) • Loop diuretics do not cause hypotension when used properly in fluid overload • Do not split the dose of diuretics: one effective dose is better than 2 ineffective ones • Tell patients to stop diuretics when no eating or drinking or with diarrhoea, or when fluid is absent • It usually takes 2-4 weeks to drift into CCF: this guides monitoring • Loop diuretics do not cause hyponatraemia when used properly (unlike bendroflumethizide) – only when excessive (or in end stage) • Monitor U&Es weekly when in diuretic phase, reducing to no less frequently than 3 monthly in maintenance in older people with frailty