What class of medication is appropriate for anti-hypertensive therapy in an elderly patient with hypertension?

Antihypertensive Therapy for Elderly Women with Hypertension

Thiazide diuretics, particularly chlorthalidone, are the optimal first-line choice for treating hypertension in elderly women, with dihydropyridine calcium channel blockers (such as amlodipine) as an equally appropriate alternative. 1

Primary First-Line Recommendation

Low-dose thiazide diuretics are the accepted first-line treatment for elderly patients with hypertension. 2 The evidence supporting this recommendation is robust:

• Chlorthalidone demonstrated superiority over lisinopril in preventing stroke and over amlodipine in preventing heart failure in older hypertensive patients in the largest head-to-head comparison trial (ALLHAT). 1

• Thiazide diuretics have been shown to reduce cardiovascular morbidity and mortality in elderly patients, including those with isolated systolic hypertension (systolic BP >160 mmHg with diastolic <90 mmHg), which affects more than half of people over age 60. 2, 3

• Start with chlorthalidone 12.5 mg daily, titrated to 25 mg if needed for blood pressure control. 3

Equally Appropriate Alternative: Calcium Channel Blockers

Dihydropyridine calcium channel blockers, particularly amlodipine, are equally effective as first-line therapy and may be preferred if thiazides are not tolerated. 1

• Calcium channel blockers are as effective as diuretics for reducing all cardiovascular events except heart failure, where thiazides show superiority. 1

• Dihydropyridine CCBs have demonstrated particular efficacy in isolated systolic hypertension, which is common in elderly women. 1, 3

• Amlodipine 2.5-5 mg daily is appropriate for elderly patients, with lower initial doses recommended due to decreased clearance and 40-60% increase in drug exposure in this population. 2, 4

Less Preferred Options

Beta-blockers are NOT recommended as first-line therapy in elderly patients unless specific comorbidities exist (coronary artery disease or heart failure). 2, 1

• Beta-blockers are less effective than thiazides as first-line treatment in elderly patients, reducing only stroke events in meta-analyses. 2

• They are significantly less effective than diuretics for stroke prevention and cardiovascular events in older adults. 1

• Beta-blockers have more side effects and reduced well-being scores compared to other antihypertensive classes in elderly patients. 5

ACE inhibitors or ARBs are reasonable alternatives but were less effective than thiazide diuretics in preventing stroke and less effective than CCBs in preventing heart failure in head-to-head trials. 1

Treatment Algorithm for Elderly Women

1. Start with monotherapy:

   • First choice: Thiazide diuretic (chlorthalidone 12.5 mg daily) 1, 3
   • Alternative: Dihydropyridine CCB (amlodipine 2.5 mg daily) 1

2. Titrate gradually over 4 weeks:

   • Initial doses and subsequent titration should be more gradual in elderly patients due to increased risk of adverse effects. 2, 3
   • Allow at least 4 weeks to observe full response unless urgent BP lowering is needed. 2

3. Add second agent if target not achieved:

   • Most elderly hypertensive patients will require combination therapy. 2, 3
   • Effective combinations: ACE inhibitor/ARB + CCB, ACE inhibitor/ARB + thiazide diuretic, or CCB + thiazide diuretic. 1
   • Submaximal doses of two drugs result in larger BP responses and fewer side effects than maximal doses of a single drug. 2

Blood Pressure Targets

• Target BP <140/90 mmHg for elderly patients, with consideration of <130/80 mmHg if well tolerated. 2, 3

• For patients aged ≥80 years, treatment should be continued or initiated, starting with monotherapy and adding a second drug if needed. 2

• Evidence from the HYVET trial supports antihypertensive treatment benefits in patients aged ≥80 years. 2

Critical Monitoring Considerations

Always measure blood pressure in both sitting and standing positions in elderly patients to assess for orthostatic hypotension. 2, 3

• Elderly patients have increased risk of postural hypotension, which can lead to falls and injury. 3

• Monitor for electrolyte abnormalities, particularly hypokalemia with thiazide therapy. 1

• Follow up within 2-4 weeks after medication initiation or dose changes to assess efficacy and adverse effects. 1

Common Pitfalls to Avoid

• Do not use rapid dose escalation in elderly patients - this increases risk of adverse effects including orthostatic hypotension and falls. 2, 3

• Do not discontinue effective and well-tolerated therapy when a patient reaches age 80 - treatment should be continued indefinitely once started. 2, 3

• Do not ignore standing blood pressure measurements - orthostatic hypotension is common and dangerous in elderly patients. 2, 3

• Do not use beta-blockers as first-line therapy unless the patient has coronary artery disease or heart failure as compelling indications. 2, 1

Special Considerations for Women

• In the ALLHAT trial, stroke rates were significantly higher with lisinopril compared to amlodipine in women (RR=1.45), supporting the preference for thiazides or CCBs as first-line therapy. 6

• Elderly women have the same proportional benefit from antihypertensive treatment as younger patients and men. 2