Goal-directed antihypertensive therapy: Lower may not always be better

Avoid misclassification

The first step in treating hypertension should be to avoid misclassification. Make sure the clinic blood pressure is measured correctly, using an appropriately sized cuff, positioning the patient properly, and following all the other recommendations.⁶⁴

However, the clinic blood pressure may not reflect true blood pressure load in up to one-third of all patients.⁶⁵ We recommend 24-hour ambulatory blood pressure monitoring⁶⁶ or home self-measurement, or both,⁶⁷ to better assess true blood pressure burden in several circumstances, including in patients with resistant hypertension (any patient who has not achieved acceptable clinic blood pressure on three or more antihypertensive medications including a diuretic or who requires four or more medications for adequate control), suspicion of white-coat hypertension (or effect), and any patient who has achieved acceptable clinic blood pressure but either has symptoms of hypotension or progressive end-organ damage.

Currently, we base therapy on out-of-office blood pressure (self-measured or by ambulatory monitoring) whenever there is a discrepancy with clinic blood pressure.

Whether therapy should be altered by other less traditional measures of blood pressure such as assessment of central aortic pressure by radial applanation tonometry,^68,69 or 24-hour ambulatory monitoring to assess nighttime blood pressures (specifically, “dipping”),⁷⁰ morning surge,⁷¹ or blood pressure variability^72,73 remains unclear and in need of randomized controlled trials.

In any patient requiring blood-pressure-lowering, we recommend lifestyle modifications.^1,2 These include exercise, weight loss, salt and alcohol restriction, evaluation for sleep apnea, and avoidance of medications known to elevate blood pressure such as nonsteroidal anti-inflammatory drugs and sympathomimetic decongestants.

Much needs to be learned

For the individual patient with unacceptably high blood pressure who is already taking multiple antihypertensive medications of different classes, it is unclear what to do. This type of patient with resistant hypertension would be an excellent candidate for a future targeting trial. Other cardiovascular risk factors should be appropriately addressed, including obesity, lipids, smoking, and poor glycemic control.⁷⁴ Each patient should be individually assessed with consideration of both global cardiovascular risk and quality-of-life issues.

Much still needs to be learned about the treatment of hypertension. The facts demonstrate that blood pressure is a strong modifiable risk factor of cardiovascular morbidity and mortality. Lowering it clearly produces benefits. It is unclear what treatment goals should be promulgated by official guidelines for large groups of patients. The resistant case remains a therapeutic dilemma with the potential for harm from overly aggressive treatment. The truly optimal level for an individual patient remains difficult to define. We anxiously await results of ongoing and future targeting trials.

CASE REVISITED

Regarding the initial case vignette, the patient is clearly not at her recommended goal blood pressure, especially given her high-risk status (diabetes mellitus and chronic kidney disease). Observational data support intensification of therapy, whereas targeting trials are essentially negative and indicate the potential for harm with overly aggressive treatment. Thus, we remain uncertain about what is correct or incorrect in terms of a targeted blood pressure, especially when applied to the individual patient.

Our approach would be to emphasize lifestyle modifications, to ensure accurate determination of her true blood pressure load (self-measurement at home or ambulatory blood pressure monitoring), to consider secondary causes of hypertension, and to educate the patient about the benefits and consequences of intensifying therapy with the aim of involving her in the decision.