What is a suitable initial antihypertensive medication for older adults with hypertension?

Initial Antihypertensive Medication for Older Adults with Hypertension

For older adults with hypertension, a thiazide diuretic, particularly chlorthalidone at a low dose, is the recommended initial antihypertensive medication due to its superior efficacy in preventing cardiovascular events and stroke. 1, 2, 3

First-Line Medication Options

Thiazide Diuretics

• Thiazide diuretics, especially chlorthalidone, are the optimal first-line medications for hypertension in older adults based on the strongest evidence for preventing cardiovascular disease outcomes 1, 2
• Low doses of thiazide diuretics are effective in controlling isolated systolic hypertension in most elderly patients and are well tolerated 4
• Thiazide diuretics are the only class of antihypertensives that has been shown to reduce risk of cardiovascular events in patients with isolated systolic hypertension 4, 3
• Low-dose regimens (e.g., chlorthalidone 12.5-15 mg, hydrochlorothiazide 12.5 mg) are recommended to minimize metabolic adverse effects while maintaining efficacy 5, 6

Alternative First-Line Options

• Calcium channel blockers (CCBs) are effective alternatives when thiazides cannot be used, and are particularly effective for stroke prevention 2
• ACE inhibitors or ARBs are effective options, especially in patients with specific comorbidities such as diabetes, chronic kidney disease, or heart failure 2, 1
• For Black older adults, thiazide diuretics or CCBs are preferred first-line agents 1, 2

Special Considerations for Older Adults

Dosing Considerations

• Start at the lowest possible dose and titrate gradually in older adults 1
• For elderly or frail patients, amlodipine can be started at 2.5 mg once daily (rather than the usual 5 mg) 7
• Elderly patients have decreased clearance of medications like amlodipine with a resulting increase of AUC of approximately 40-60%, requiring lower initial doses 7

Blood Pressure Targets

• For adults aged 65-79 years, a target systolic blood pressure of <140 mmHg is appropriate 1
• For adults aged 80 years and older, a target of 140-145 mmHg, if tolerated, is acceptable 1
• Avoid excessive lowering of diastolic BP below 70-75 mmHg in older patients with coronary heart disease to prevent reduced coronary blood flow 1

Monotherapy vs. Combination Therapy

• For Stage 1 hypertension (130-139/80-89 mmHg), single-agent therapy is reasonable 1, 2
• For Stage 2 hypertension (≥140/90 mmHg) or BP ≥20/10 mmHg above target, initiate treatment with two antihypertensive medications 1
• When combination therapy is needed, use agents with complementary mechanisms of action (e.g., thiazide diuretic plus ACE inhibitor or ARB) 1
• Single-pill combinations can improve adherence in older adults 1

Common Pitfalls and Caveats

• Beta-blockers are not recommended as first-line therapy unless there are specific indications such as prior MI, active angina, or heart failure 2
• Alpha-blockers should not be used as first-line therapy due to inferior cardiovascular protection 2
• The combination of ACE inhibitors and ARBs should be avoided due to increased risk of adverse effects without additional benefit 1, 2
• Caution is needed in patients with a history of gout, as thiazide diuretics may increase the risk of gout attacks 6
• For older adults with multiple comorbidities or frailty, treatment decisions should be based on clinical judgment, considering risk/benefit ratio 1

Monitoring and Follow-up

• Monitor for electrolyte disturbances (particularly potassium), renal function, and orthostatic hypotension when initiating thiazide diuretics in older adults 1
• Assess BP control within 3 months of starting therapy 1
• If BP remains uncontrolled on initial therapy, add a second agent from a different class rather than maximizing the dose of the first agent 1