In the News

Treating hypertension in the elderly, predicting ICD complication risk, and more.

Consensus paper: treat hypertension in elderly

Major medical organizations recently released an expert consensus document to help clinicians manage older patients with hypertension, or at risk for hypertension.

Sixty-four percent of U.S. men and 78% of U.S. women older than 65 years have high blood pressure, and one in three men and one in four women over age 80 have adequate control of their blood pressure, the document noted. Results from the Hypertension in the Very Elderly Trial (HYVET) in 2008 showed clear benefits for using antihypertensive therapy in people 80 years and older, including a 30% reduction in stroke, 23% reduction in cardiac death, 64% reduction in heart failure and 21% reduction in all-cause mortality. That study became the main impetus for the new consensus document.

Some of the recommendations addressed in the consensus document include:

  • Achieved systolic blood pressure values less than 140 mm Hg are appropriate goals for most patients 79 years of age or younger; for those 80 years of age or older, 140 to 145 mm Hg, if tolerated, can be acceptable.
  • Systolic blood pressure less than 130 and diastolic blood pressure less than 65 should be avoided since it is not known at which blood pressure values vital organ perfusion is impaired.
  • Angiotensin-converting enzyme inhibitors, beta-blockers, angiotensin-receptor blockers, diuretics and calcium-channel blockers are all effective in lowering blood pressure and reducing cardiovascular outcomes among the elderly. The choice between drugs should be based on efficacy, tolerability, comorbidities and cost.
  • Antihypertensive drugs should generally be started at the lowest dose, then increased in gradual increments as tolerated. If the first drug reaches its “full dose” (not necessarily the maximum recommended dose), then a second should be added—a diuretic if it wasn't the first drug. If the antihypertensive response is inadequate after reaching full doses of two classes of drugs, a third drug from another class should be added. When blood pressure is more than 20/10 mm Hg above goal, therapy should be initiated with two antihypertensive drugs. Consider reasons for inadequate response, including polypharmacy, nonadherence and potential drug interactions.
  • Conduct routine monitoring of blood pressure, including taking blood pressure measures in the standing position.
  • Lifestyle changes may be all that are needed for milder hypertension, and may allow reduction of drug doses. This includes regular physical activity, restriction of salt, weight control, smoking cessation and avoiding excessive alcohol intake (more than two drinks for men and one drink for women daily).
  • The high cost of blood pressure-lowering medications contributes to low rates of blood pressure control in the elderly and should be discussed with patients.

The American College of Cardiology (ACC) and the American Heart Association (AHA) released the expert consensus document, which was developed with other medical societies. The consensus statement appeared in the May 17 Journal of the American College of Cardiology and was posted ahead of print on the ACC and AHA websites.

Score predicts complication risk from ICD implantation

A new score can help predict patients' risk of complications after implantable cardioverter-defibrillator (ICD) implantation, a study found.

Researchers analyzed data from 268,701 implants that were submitted to the ICD Registry (ICD-R), and developed logistic regression models to identify 29 variables associated with the risk of acute complications in the hospital, including in-hospital death. These variables included admission patient characteristics, history and risk factors, diagnostic studies and device type. Information came from 1,300 centers that entered data between January 1, 2006 and June 30, 2008. Results were published in the May 17 Circulation.

Of the total population, 3.2% experienced an adverse event, including in-hospital death (0.38% of the total population). A risk score with 10 readily available clinical items was developed to identify patients at high and low risk of complications. Risk variables, with point values, included: age at least 70 years (1 point), female sex (2 points), New York Heart Association class III (1 point) or IV (3 points), atrial fibrillation (1 point), prior valve surgery (3 points), chronic lung disease (2 points), blood urea nitrogen above 30 (2 points), reimplantation for reasons other than battery change (6 points), ICD type dual chamber (2 points) or biventricular (4 points), and nonelective ICD implant (3 points).

The risk of any in-hospital complication jumped from 0.6% among patients with a score of 5 or less (8.4% of the population) to 8.4% among patients with at least 19 risk points (3.9% of the population). The risk of in-hospital mortality increased from less than 0.1% among patients with a risk score of 0 (19.7% of the population) to 2.4% among patients with a risk score of 7 or more (8.6% of the population).

The data in this study are inclusive of the majority of ICD implants in the U.S. between early 2006 and mid-2008—a broad scope, the authors noted. The risk score comprises readily available clinical information that can identify high- and low-risk subsets of patients, and can help with clinical decision making, especially post-procedure. For example, patients with a score of 9 or less might be triaged to observation units or discharged home the same day, while those with a score of 13 or greater might need higher-intensity postprocedure care, or to have the procedure postponed until their condition stabilizes, the authors noted.

Pulmonary embolism may be overdiagnosed in the U.S.

Use of computed tomographic pulmonary angiography (CTPA) may have led to overdiagnosis of pulmonary embolism (PE) in the U.S., according to a recent study.

Researchers conducted a time-trend analysis of the Nationwide Inpatient Sample and Multiple Cause-of-Death databases to determine how the introduction of CTPA, an extremely sensitive test, has affected PE incidence, mortality rates and treatment complications in the U.S. Age-adjusted incidence, mortality and treatment complications were compared in adults before CTPA was introduced (1993-1998) and afterward (1998-2006). Treatment complications were defined as in-hospital gastrointestinal tract or intracranial hemorrhage or secondary thrombocytopenia. Results were published in the May 9 Archives of Internal Medicine.

Age-adjusted PE incidence did not change in the period before CTPA was introduced (58.8 to 62.3 per 100,000; P=0.64). Afterward, however, age-adjusted incidence increased by 81% (from 62.1 to 112.3 per 100,000; P<0.001). Mortality from PE decreased 8% (P<0.001) in the period before CTPA was introduced and 3% (P=0.02) in the period afterward. Case fatality (number of deaths/people diagnosed) decreased in both periods but more so after CTPA was introduced (8% vs. 36%). Rates of presumed complications related to PE anticoagulation were stable before CTPA but increased by 71% afterward, from 3.1 to 5.3 per 100,000 (P=0.001).

The study had several limitations, including the potential of confounding by “upcoding” and potential undercounting of death from PE on death certificates. The authors also noted that some cases of PE might have been false-positives. However, they concluded that CTPA was associated with indicators of overdiagnosis, and that with more emboli now being diagnosed, researchers need to determine best management for different types. “It is time to strengthen the evidence base: a trial randomizing stable patients with small emboli to observation vs. anticoagulation would help determine whether all patients with PE require treatment,” they wrote.

An accompanying commentary agreed that overdiagnosis exists but also noted that therapy for PE may have benefits in a subset of patients with incidental findings. Future studies on this issue should take care to identify these patients, the author wrote, since many cases of acute PE are not recognized until after death. “Prevention remains crucial, and recent data continue to suggest that underprophylaxis is a worldwide problem,” he concluded.

Bleeding risk with dabigatran varies by dose, patient age

The bleeding risk associated with dabigatran compared to warfarin is reduced at a lower dose and in patients younger than 75 years, a study found.

Researchers studied bleeding risk for 18,113 patients with atrial fibrillation who had at least one additional risk factor for stroke. They were randomized to either 110 mg dabigatran twice a day, 150 mg dabigatran twice daily, or warfarin dosing adjusted to an international normalized ratio (INR) of 2.0 to 3.0. Patients were followed for a median of two years. Major bleeding was the main safety outcome, and stroke or systemic embolism was the main efficacy outcome. Major bleeding was defined as bleeding associated with a reduction in hemoglobin level of at least 2.0 g/dL, transfusion of at least 2U of blood, or symptomatic bleeding into a critical area or organ. Major bleeding was separated into intracranial (intracerebral, subdural) and extracranial (gastrointestinal, nongastrointestinal). Relative risks of major bleeding were examined in prespecified age subgroups of less than 65, 65 to 74 and at least 75 years. Results were published in the May 31 Circulation.

In general, the 110-mg, twice-daily dose of dabigatran was associated with a lower risk of major bleeding than warfarin (2.87% vs. 3.57%; P=0.002), while the 150-mg, twice daily dabigatran dose had a similar risk as warfarin (3.31 vs. 3.57%; P=0.32). The lower-dose dabigatran regimen was associated with a lower risk of major bleeding than warfarin in patients aged less than 75 years (1.89% vs. 3.04%; P<0.001) and a similar risk in those aged at least 75 years (4.43% vs. 4.37%; P=0.89). The higher-dose dabigatran regimen was also associated with a lower bleeding risk in patients aged less than 75 years (2.12% vs. 3.04%; P<0.001) but a trend toward higher risk of major bleeding in those aged at least 75 years (5.10% vs. 4.37%; P=0.07). The interaction with age (P<0.001) was evident for extracranial bleeding but not for intracranial bleeding; the risk of the latter was lower with dabigatran than warfarin, regardless of age. Both doses of dabigatran were associated with a lower risk of minor bleeding than warfarin; the higher dose was associated with more gastrointestinal bleeding than warfarin.

A finding of a greater-than-twofold higher risk of major bleeding with either dabigatran or warfarin in patients with a creatinine clearance less than 50 mL/min (vs. those with ≥80 mL/min clearance) is consistent with published reports that renal function is a powerful predictor of bleeding risk in patients who take warfarin, the authors noted. In general, this study's results indicate that for patients younger than 75 years, “the higher dabigatran dose seems preferable because of the lower risk of stroke without any increased risk of bleeding,” while the 110-mg dabigatran dose might be considered for patients 75 years and older, they concluded.