What are the key pharmacological considerations when prescribing antihypertensive medications in elderly patients?

When prescribing antihypertensive medications to elderly patients, key pharmacological considerations include careful drug selection, dose titration, monitoring for adverse effects, and individualising treatment based on frailty, comorbidities, and tolerability. NICE guidelines recommend offering a calcium-channel blocker (CCB) as first-line treatment for adults aged 55 or over without type 2 diabetes, reflecting evidence of efficacy and tolerability in this age group NICE NG136. If CCBs are not tolerated, thiazide-like diuretics such as indapamide are preferred over conventional thiazides due to better safety profiles NICE NG136.

Blood pressure targets are also adjusted for age, with a clinic target of below 150/90 mmHg for those aged 80 and over, using clinical judgement especially in frail or multimorbid patients NICE NG136. This acknowledges the increased risk of adverse events such as orthostatic hypotension and falls in the elderly. Pharmacokinetic and pharmacodynamic changes in older adults, including reduced renal clearance and altered drug metabolism, necessitate starting at lower doses and slow titration to minimise side effects Peeters et al. 2019.

Polypharmacy and multimorbidity are common in elderly patients, increasing the risk of drug interactions and adverse effects; thus, regular medication review and shared decision-making are essential to optimise adherence and safety NICE NG136. ACE inhibitors or angiotensin II receptor blockers (ARBs) may be used but require caution due to risks of hyperkalaemia and renal impairment, especially in those with chronic kidney disease or heart failure Adams & Mosler 2022. Combining ACE inhibitors with ARBs is contraindicated NICE NG136.

Monitoring for side effects such as electrolyte disturbances, renal function decline, and symptomatic hypotension is critical, as elderly patients are more vulnerable to these complications Peeters et al. 2019. Additionally, once-daily dosing regimens are preferred to improve adherence NICE NG136. Overall, treatment should be individualised, balancing cardiovascular risk reduction with the potential for adverse effects, and incorporating patient preferences and frailty status into clinical decisions NICE NG136.