Treating hypertension in older patients
Treating hypertension in older patients
The age-adjusted prevalence of hypertension among U.S. adults aged 18 years and older was recently found to be 29.1% in 2011-2012.1 Prevalence increased with age, from 7.3% in persons aged 18 to 39 years, to 32.4% in persons aged 40 to 59 years, to 65% among persons aged 60 years and older. Special considerations are associated with the treatment of hypertension in older persons.
Clinicians who are faced with managing this highly prevalent condition in this extremely vulnerable group can always consult the expert consensus document from the American College of Cardiology and the American Heart Association.2
"There is very little difference in treating older versus younger patients," commented Wilbert S. Aronow, MD, professor of medicine at New York Medical College/Westchester Medical Center and co-chair of the committee that wrote the document. "You use the same drugs, with the same indications."
But comorbidities and interactions with other drugs are likely to play a larger role in medication choice, and the risk of adverse effects—particularly orthostatic hypotension—require particular attention, Dr. Aronow advised.
Evaluation and diagnosis
As with younger patients, hypertension in the elderly is diagnosed on the basis of three measurements on at least two separate occasions. But in the older patient population, it is important for both initial diagnosis and subsequent monitoring to include a measurement taken while the individual is standing for one to three minutes to screen for orthostatic hypotension.
Orthostatic hypotension is linked to a heightened risk of falls and makes it essential that clinicians avoid overestimation of BP due to such sources of error as pseudohypertension (systolic BP that appears increased due to noncompressible brachial arteries) and the "white-coat effect" of transient elevation in the medical office, which tends to be more pronounced in older patients.
The guideline authors recommend home monitoring, which has better prognostic and diagnostic accuracy than clinical measurement. Ambulatory 24-hour monitoring provides even more detailed information, including the possibility of postprandial hypotension, and should be considered when there are strong reasons to suspect the diagnosis (e.g., the absence of target-organ damage).
The document notes that while there is little evidence of the need for routine laboratory testing as part of the evaluation, information relevant to organ damage and additional risk factors should be available through urinalysis, blood chemistry (including potassium and creatinine), blood lipids, fasting blood glucose or hemoglobin A1c, and electrocardiography.
Although the goal of 140/90 mm Hg is generally recommended for patients at any age with uncomplicated hypertension, it is unclear that this target is appropriate for those aged 80 years and older, wrote the guideline authors.
Taking existing data into account—including the only randomized controlled trial of treatment for patients in this age range3—"The goal for people aged 79 years and younger should be 130-139 systolic; and for those 80 years and older, 140-145 if tolerated," Dr. Aronow affirmed. In this older group, systolic pressures <130 should be avoided.
As for diastolic pressure, "We do not have enough data, but based on what is available, we would not want to get below 65 in an older individual." In reality, very few elderly patients have diastolic hypertension—fewer than 1% of those older than age 80 years, according to Dr. Aronow.
Although existing guidelines suggest lower target pressures for individuals of all ages with diabetes and coronary artery disease (CAD), there is reason to question this recommendation for older patients. What limited data exist for this population indicate that risk is lowest at 135/75 for CAD patients aged 70 to 80 years and at 140/70 for those who are older. Random controlled trial data for elderly individuals with diabetes found no benefit with systolic pressures <120 compared with <140.
As with younger patients, lifestyle modification should be part of hypertension management and may be sufficient when hypertension is mild. Key factors include smoking cessation, weight control, sodium restriction, increased potassium intake, moderation in alcohol consumption, and exercise.
The guideline authors pointed out that Medicare benefits for smoking-cessation counseling and medication have expanded and that weight loss has been shown to be effective for BP reduction in older individuals. Sodium restriction appears to have greater BP benefits for older persons than for younger.
There is evidence that aerobic training reduces BP in individuals aged 60 to 69 years and 70 to 79 years. In addition, the finding that increasing exercise intensity beyond the moderate level carries no additional benefit "is especially meaningful for the elderly," the authors reported.
Hypertension is treated with the same drugs for older and younger patients, but extra caution must be taken to account for age-related changes in metabolism and pharmacodynamics. Clinicians are advised to start at the lowest dose and increase gradually to the highest tolerated dose. Most older patients will require two or more medications to achieve adequate BP control.
Cardiovascular and other benefits are a function of BP reduction, regardless of the medication. "It does not matter if you use an angiotensin-converting enzyme (ACE) inhibitor, angiotensin receptor blocker (ARB), calcium channel blocker, beta blocker, or diuretic. The choice will depend on comorbidities, adverse effects, and cost," Dr. Aronow explained.
A diuretic is frequently indicated as the initial or second drug, according to the consensus document. Diuretics should be avoided in patients with or at high risk for diabetes, however, because these agents increase hyperglycemia and diabetes incidence. As an alternative, Dr. Aranow recommended prescribing an ACE inhibitor or an ARB instead.
For hypertensive patients who have suffred a recent MI, the drug regimen should include a beta blocker—usually in combination with a calcium channel blocker, diuretic, or ACE inhibitor—and an aldosterone antagonist if needed.
For older individuals with heart failure, the recommended choice is diuretics, beta blockers, or ACE inhibitors or ARBs, to which an aldosterone antagonist may be added.
BP control is particularly important for older patients with a history of stroke or transient ischemic attack. For such individuals, the authors advocate treatment with a diuretic and an ACE inhibitor, while noting that the magnitude of pressure reduction is probably more important than the agent used.
A regimen that includes an ACE inhibitor or an ARB is indicated for older patients with chronic kidney disease.
Whatever the regimen, the danger of drug-drug interactions must be kept in mind. The average elderly patient takes more than six prescription medications as well as OTC preparations. The BP-elevating effects of such drugs should be assessed, particularly in cases of apparent treatment resistance.
Common culprits include corticosteroids, sympathomimetics, and, perhaps most insidiously, nonsteroidal anti-inflammatory drugs (NSAIDs). Dr. Aronow stated that in addition to increasing BP, NSAIDs interfere with other medications' antihypertensive effects, and may accentuate hypertension-associated risks of heart failure, renal failure, and cardiovascular events.
Carl Sherman is a freelance medical writer in New York City.
- Nwankwo T, Yoon SS, Burt V, Gu Q. Hypertension among adults in the United States: national health and nutrition examination survey, 2011-2012. NCHS Data Brief. 2013;133:1-8.
- Aronow WS, Fleg JL, Pepine CJ, et al. ACCF/AHA 2011 expert consensus document on hypertension in the elderly: a report of the American College of Cardiology Foundation Task Force on Clinical Expert Consensus Documents developed in collaboration with the American Academy of Neurology, American Geriatrics Society, American Society for Preventive Cardiology, American Society of Hypertension, American Society of Nephrology, Association of Black Cardiologists, and European Society of Hypertension. J Am Soc Hypertens. 2011;5:259-352. Available at www.medscape.com/viewarticle/742637.
- Beckett NS, Peters R, Fletcher AE et al. Treatment of hypertension in patients 80 years of age or older. N Engl J Med. 2008 May 1;358(18):1887-98. Available at www.nejm.org/doi/full/10.1056/NEJMoa0801369.
All electronic documents accessed December 3, 2013.