Hypertension: Pitfalls to prescribing for patients with high blood pressure
Chronic psychiatric disorders go hand-in-hand with risk factors for elevated blood pressure. Here are diagnostic and treatment strategies to help you detect comorbid hypertension and keep blood pressure in control.
Table 2
ANTIHYPERTENSIVE MEDICATIONS AND SIDE EFFECTS
| Antihypertensive class | Agent(s) | Possible associated psychiatric symptoms |
|---|---|---|
| Beta-adrenergic blocking agents | Propranolol, atenolol, metoprolol, others | Fatigue, depression, psychosis, delirium, anxiety, sexual dysfunction, nightmares, hallucinations* |
| Angiotensin-converting enzyme (ACE) inhibitors | Captopril, enalapril, lisinopril, ramipril, others | Mania, anxiety, hallucinations |
| Angiotensin II receptor blockers (ARBs or AIIAs) | Losartan, valsartan, others | Probably same as ACE inhibitors |
| Diuretics | Hydrochlorothiazide, furosemide | Sexual dysfunction, depression |
| Calcium-channel blockers | Nifedipine, verapamil, diltiazem | Dizziness, headache, flushing, tachycardia, depression |
| Alpha-adrenergic blockers | Prazosin, terazosin, doxazosin | Syncope, dizziness and vertigo, palpitations, drowsiness, weakness, confusion |
| Central alpha-adrenergic agonists | Clonidine, methyldopa | Drowsiness, sedation, fatigue, depression, impotence, delirium, psychosis, nightmares, amnesia |
| Direct vasodilators | Hydralazine, minoxidil | Tachycardia, headache, dizziness |
| Peripheral adrenergic neuron antagonists | Reserpine, guanadrel | Drowsiness, depression, nightmares, tardive dyskinesia |
| *May occur with ophthalmic preparations | ||
A thorough history and physical examination should be performed to assess these four areas. Routine laboratory testing for the hypertensive patient should include a urinalysis, a complete blood count, an assessment of blood chemistries (potassium, sodium, creatinine, fasting glucose, fasting lipid profile), and a 12-lead electrocardiogram.
Treating hypertension
Many medications are used to treat hypertension. Most classes of antihypertensive agents have been shown to be about equally effective in lowering blood pressure.
All other factors being equal, the sixth report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure (JNC-VI) recommends initial treatment with a diuretic or beta-blocker. These classes of drugs have been shown to significantly reduce overall hypertension-related mortality.
Most patients with hypertension—particularly the elderly, patients with diabetes mellitus, and those with renal disease—will need two or more agents to control their blood pressure. Avoid prescribing agents that may worsen an existing condition (e.g., beta-blockers may worsen bronchospasm in patients with asthma). Use agents that may help improve comorbid conditions (e.g., beta-blockers have been shown to reduce mortality in patients with previous MI).
The Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure (JNC), which has issued six previous reports on hypertension control, is expected to issue updated recommendations within the next year. Angiotensin-converting enzyme inhibitors, calcium-channel blockers, and angiotensin II receptor antagonists may then be recommended as initial treatment options, along with the previously preferred classes of diuretics and beta-blockers.
A wealth of data has been obtained from multiple randomized, controlled studies since JNC released its most recent report in 1997. Turner et al used genetic analysis to identify individuals with essential hypertension who had a common genetic mutation that resulted in a renal absorption defect. Study participants with this mutation responded much better to diuretic therapy (which specifically targeted the underlying defect) than did those without the defect.8
In the future, determination of genetic polymorphism before prescribing medications may reduce side effects and increase efficacy in treating a variety of disorders, including hypertension.
Potential side effects, some of which mimic or are commonly found in psychiatric disorders, must be considered when choosing an antihypertensive agent. Table 2 lists nine classes of antihypertensives and some associated side effects. Also consider the agent’s cost, convenience of administration, direct-to-consumer advertising, and the patient’s age or race. For example, beta-blockers tend to be less effective in black or elderly patients than in other demographic groups.
Nonpharmacologic hypertension management emphasizes weight reduction, moderation of alcohol intake, regular aerobic exercise, dietary restriction of sodium, and smoking cessation. Most studies of these behavioral interventions have demonstrated a short-term benefit in decreasing blood pressure, but long-term adherence to them is disappointing. Relaxation therapies and biofeedback have been advocated for hypertension, but proof of their efficacy is lacking.7
As more is learned about genetic and other causes of hypertension, more-effective treatments for hypertension could become available (Box).
Treating high-risk groups
Special considerations apply to two patient groups with a high prevalence of hypertension—those age 65 and older and those with diabetes.
Older patients. Treatment benefits are more pronounced in patients age 65 or older because of their greater absolute risk for cardiovascular events. Also, systolic blood pressures increase with aging as the arterial tree becomes progressively less distensible.
Older patients often will require more than one drug to control their blood pressure. The initial dosages should be low and gradually titrated upward as needed. To minimize side effects, use smaller doses of multiple agents that are well tolerated instead of high-dose monotherapy.
A diuretic is often recommended as initial treatment for older patients, though a long-acting dihydropyridine calcium-channel blocker is a reasonable alternative. An ACE inhibitor is recommended for older patients with diabetes, systolic congestive heart failure, or previous MI. An alpha blocker should not be used as initial therapy for hypertension in the elderly because of relative lack of efficacy in preventing cardiovascular events.
Patients with diabetes. Aggressive blood pressure control is especially important in the patient with diabetes, which is the leading cause of end-stage renal disease. Most patients with diabetes also have hypertension—which accelerates their renal disease as well as cardiovascular disease. Blood pressure control goals significantly below 140/90 mm Hg are recommended (120 to 135 mm Hg systolic, 80 to 85 mm Hg diastolic) if diabetes is present.
