In the Literature

The Hospitalist. 2010 April;2010(04):

April 1, 2010 | The Hospitalist

Charles Baillie, MD ; Elizabeth Marandola, MSN, ARNP ; Janelle Ocampo, PharmD, BCPS ; Craig A. Umscheid, MD, MSCE ; Section OF

Synopsis: The study randomized 806 patients with renal-artery stenosis to receive either medical therapy alone (N=403) or medical management plus endovascular revascularization (N=403).

The majority of the patients who underwent revascularization (95%) received a stent.

The data show no significant difference between the two groups in the rate of progression of renal dysfunction, systolic blood pressure, rates of adverse renal and cardiovascular events, and overall survival. Of the 359 patients who underwent revascularization, 23 (6%) experienced serious complications from the procedure, including two deaths and three cases of amputated toes or limbs.

The primary limitation of this trial is the population studied. The trial only included subjects for whom revascularization offered uncertain clinical benefits, according to their doctor. Those subjects for whom revascularization offered certain clinical benefits, as noted by their primary-care physician (PCP), were excluded from the study. Examples include patients presenting with rapidly progressive renal dysfunction or pulmonary edema thought to be a result of renal-artery stenosis.

Bottom line: Revascularization provides no benefit to most patients with renal-artery stenosis, and is associated with some risk.

Citation: ASTRAL investigators, Wheatley K, Ives N, et al. Revascularization versus medical therapy for renal-artery stenosis. N Eng J Med. 2009;361(20):1953-1962.

Dabigatran as Effective as Warfarin in Treatment of Acute VTE

Clinical question: Is dabigatran a safe and effective alternative to warfarin for treatment of acute VTE?

Background: Parenteral anticoagulation followed by warfarin is the standard of care for acute VTE. Warfarin requires frequent monitoring and has numerous drug and food interactions. Dabigatran, which the FDA has yet to approve for use in the U.S., is an oral direct thrombin inhibitor that does not require laboratory monitoring. The role of dabigatran in acute VTE has not been evaluated.

Study design: Randomized, double-blind, noninferiority trial.

Setting: Two hundred twenty-two clinical centers in 29 countries.

Synopsis: This study randomized 2,564 patients with documented VTE (either DVT or pulmonary embolism [PE]) to receive dabigatran 150mg twice daily or warfarin after at least five days of a parenteral anticoagulant. Warfarin was dose-adjusted to an INR goal of 2.0-3.0. The primary outcome was incidence of recurrent VTE and related deaths at six months.

A total of 2.4% of patients assigned to dabigatran and 2.1% of patients assigned to warfarin had recurrent VTE (HR 1.10; 95% CI, 0.8-1.5), which met criteria for noninferiority. Major bleeding occurred in 1.6% of patients assigned to dabigatran and 1.9% assigned to warfarin (HR 0.82; 95% CI, 0.45-1.48). There was no difference between groups in overall adverse effects. Discontinuation due to adverse events was 9% with dabigatran compared with 6.8% with warfarin (P=0.05). Dyspepsia was more common with dabigatran (P<0.001).

Bottom line: Following parenteral anticoagulation, dabigatran is a safe and effective alternative to warfarin for the treatment of acute VTE and does not require therapeutic monitoring.

Citation: Schulman S, Kearon C, Kakkar AK, et al. Dabigatran versus warfarin in the treatment of acute venous thromboembolism. N Engl J Med. 2009;361(24):2342-2352.

Clinical Shorts

COMBINATION VACCINE REDUCES RISK OF HIV INFECTION

In a randomized, double-blind, placebo-controlled trial in Thailand, an HIV vaccine reduced the risk of HIV by 31%. Vaccination did not affect CD4 count or viremia in those diagnosed with HIV.

Citation: Rerks-Ngarm S, Pitisuttithum P, Nitayaphan S, et al. Vaccination with ALVAC and AIDSVAX to prevent HIV-1 infection in Thailand. N Engl J Med. 2009;361(23):2209-2220.

GRAM-NEGATIVE PROSTHETIC JOINT INFECTIONS BEST TREATED WITH EXCHANGE OR RESECTION OF PROSTHESIS

In a single-institution, retrospective, cohort analysis of prosthetic joint infections, 15% of cases involved gram-negative organisms. Of these, debridement alone resulted in more treatment failures than two-stage exchange or resection arthroplasties.

Citation: Hsieh PH, Lee MS, Hsu KY, Chang YH, Shih HN, Ueng SW. Gram-negative prosthetic joint infections: risk factors and outcome of treatment. Clin Infect Dis. 2009;49(7):1036-1043.

GLUCOCORTICOIDS ASSOCIATED WITH AN INCREASED RISK FOR ATRIAL FIBRILLATION

This large, population-based, case-control study in Denmark found that current glucocorticoid use increased the risk of first hospital diagnosis of atrial fibrillation or flutter, while former use did not.

Citation: Christiansen CF, Christensen S, Mehnert F, Cummings SR, Chapurlat RD, Sørensen HT. Glucocorticoid use and risk of atrial fibrillation or flutter: a population-based, case-control study. Arch Intern Med. 2009;169(18):1677-1683.

FEW PHYSICIANS CHOOSE THERAPY CONSISTENT WITH HEALTHCARE-ASSOCIATED PNEUMONIA GUIDELINES

In an online survey, most physicians reported they were aware of and practiced according to published guidelines for healthcare-associated pneumonia (HCAP). However, testing showed that the majority did not choose guideline-concordant therapy.

Citation: Seymann GB, Di Francesco L, Sharpe B, et al. The HCAP gap: differences between self-reported practice patterns and published guidelines for health care-associated pneumonia. Clin Infect Dis. 2009;49(12):1868-1874.