From the Guidelines
For an 84-year-old female patient with hypertension and impaired renal function, a calcium channel blocker (CCB) such as amlodipine at a starting dose of 2.5 mg daily is generally recommended as the initial antihypertensive medication. This recommendation is based on the most recent guidelines for the management of elevated blood pressure and hypertension, which suggest that treatment for older patients aged <85 years who are not moderately to severely frail should follow the same guidelines as for younger people, provided BP-lowering treatment is well tolerated 1. Given the patient's advanced age and impaired renal function, with an eGFR of 48, it is crucial to select an antihypertensive medication that is effective, well-tolerated, and minimizes the risk of adverse effects.
When considering the initial antihypertensive medication, it's essential to weigh the benefits and risks of different classes of medications. For instance, diuretics, which are commonly used in the treatment of hypertension, can cause hypovolaemia, postural hypotension, and electrolyte disturbances, particularly in elderly patients with impaired renal function 1. On the other hand, CCBs like amlodipine are preferred in elderly patients with renal impairment because they effectively lower blood pressure without worsening kidney function and have minimal drug interactions.
The starting dose of 2.5 mg daily for amlodipine is appropriate given the patient's advanced age, allowing for potential titration up to 5-10 mg daily based on blood pressure response and tolerability. Alternatively, an angiotensin receptor blocker (ARB) like losartan starting at 25 mg daily could be considered, though careful monitoring of renal function and potassium levels is essential due to the risk of hyperkalaemia, particularly in patients with chronic kidney disease (CKD) 1.
When initiating therapy, blood pressure should be lowered gradually to avoid orthostatic hypotension, with a target systolic blood pressure of 130-150 mmHg rather than more aggressive targets used in younger patients. Close monitoring of renal function, electrolytes, and blood pressure (both sitting and standing) is necessary during the first few weeks of treatment to ensure safety and efficacy. Before starting or intensifying BP-lowering medication, it is also recommended to test for orthostatic hypotension by measuring BP 1 and/or 3 min after standing, following a period of sitting or lying down for 5 min 1.
In summary, the choice of initial antihypertensive medication for an 84-year-old female patient with hypertension and impaired renal function should prioritize medications that are effective, safe, and minimize the risk of adverse effects, with CCBs like amlodipine being a preferred option due to their favorable profile in elderly patients with renal impairment.
From the FDA Drug Label
The recommended starting dose in adult patients with hypertension is not explicitly stated for patients with impaired renal function, but it is stated that "No dose adjustment of lisinopril tablets is required in patients with creatinine clearance > 30 mL/min. In patients with creatinine clearance ≥ 10 mL/min and ≤ 30 mL/min, reduce the initial dose of lisinopril tablets to half of the usual recommended dose i.e., hypertension, 5 mg; Doses above 0.61 mg per kg (or in excess of 40 mg) have not been studied in pediatric patients [see Clinical Pharmacology (12. 3)]. For patients on hemodialysis or creatinine clearance < 10 mL/min, the recommended initial dose is 2.5 mg once daily
For an 84-year-old female patient with hypertension and an eGFR of 48, which is equivalent to a creatinine clearance > 30 mL/min, no dose adjustment is required. The recommended initial dose of lisinopril is 5 mg once daily 2.
From the Research
Recommended Initial Antihypertensive Medication
For an 84-year-old female patient with hypertension and impaired renal function (eGFR of 48), the recommended initial antihypertensive medication is:
- Angiotensin II receptor blocker (ARB) or angiotensin-converting enzyme inhibitor (ACEI) 3
- Alternatively, a calcium channel blocker (CCB) may be considered, especially if the patient has risk factors for cardiovascular events 3, 4
Considerations for Renal Function
When treating patients with impaired renal function, it is essential to:
- Start with a lower dose of ARB or ACEI and monitor serum creatinine and potassium levels every 2 weeks 3
- Consider the patient's glomerular filtration rate (GFR) when selecting the initial dose of lisinopril, an ACEI 5, 6
- Monitor renal function and adjust the medication as needed to prevent further decline in renal function 7, 5, 6
Evidence from Clinical Studies
Clinical studies have shown that:
- Lisinopril, an ACEI, is effective in reducing blood pressure in elderly patients with hypertension and impaired renal function 7, 5, 6
- CCBs have similar effects on blood pressure, mortality, heart failure, stroke, and renal function compared to RAAS blockades in patients with CKD stage 3 to 5D and hypertension 4