Journal Watch: Recent studies of note

Recent studies about decreasing cardiogenic shock, Geneva scoring for pulmonary embolism, and other topics.

Patient management changes decreased incidence, deaths from cardiogenic shock

Angioplasty may be reducing the incidence of cardiogenic shock by improving blood flow to the damaged heart muscle, a November study in the Annals of Internal Medicine reported. Researchers carefully reviewed data from a hospital registry from Switzerland of more than 23,000 patients to assess associations of therapeutic management with death and shock development during hospitalization. Rates of cardiogenic shock in patients with acute coronary syndromes (a term that encompasses myocardial infarction and other conditions) declined from 1997 to 2006.

Geneva scoring simplified for pulmonary embolism

A simplified version of the revised Geneva score used to evaluate the likelihood of pulmonary embolism (PE) does not decrease diagnostic accuracy, according to a study in the Oct. 27 Archives of Internal Medicine.

Rather than relying on symptom-weighted scores, the new system attributes one point to each of the following items:

  • 65 years of age or older,
  • history of deep venous thrombosis (DVT) or PE,
  • general anesthesia for surgery or lower-limb fracture within a month,
  • active malignancy,
  • unilateral lower-limb pain,
  • hemoptysis,
  • heart rate of 75 or above,
  • pain on lower-limb palpation, and
  • unilateral edema.

Patients with 2 points or less are considered unlikely to have PE.

Researchers looked retrospectively at data from 1,049 patients from two large prospective diagnostic trials that included patients with suspected PE. The findings, which included an overall prevalence of VTE of 23%, were combined to validate the simplified revised Geneva score. There was no significant statistical difference in the diagnostic accuracy between the revised Geneva score and the simplified revised Geneva score.

In the three month follow-up period after the new simplified scoring version was applied, no patient who had either a “low clinical probability” score or a “PE unlikely” score along with a normal D-dimer test was diagnosed with a VTE.

The simplified score is likely to be easier to compute and may reduce errors in clinical practice in busy environments with a heavy workload, the authors say. In clinical practice, the probability of PE would actually be up to 3% in this patient population, and the simplified CDR should next be tested more vigorously in a prospective trial to confirm their findings.

Sudden cardiac death is top mortality risk for dialysis patients

Sudden cardiac death (SCD) emerged as the top cause of death for patients on dialysis, according to a Johns Hopkins study soon to be published in Kidney International.

The study identifies systemic inflammatory response and malnutrition, both common among end-stage renal disease (ESRD) patients, as key risk factors for the fatal heart attacks. The stress of kidney failure, loss of appetite and a highly restricted diet are responsible for the prevalence of malnutrition in this population.

A 10-year retrospective analysis of more than 1,000 ESRD patients showed that out of 658 patient deaths, 146 were the result of SCD. Blood test results revealed that patients with high levels of either hsCRP or IL-6 were twice as likely to die from SCD as those with low levels of these proteins. Low albumin levels were associated with a 1.35 times greater risk of dying of SCD than high levels, and those with low levels of albumin and high levels of hsCRP were four times more likely to die of SCD than those with high levels of albumin and low levels of hsCRP. Results indicate that ESRD patients with low albumin and/or high IL-6 and hsCRP are at a significantly higher risk of SCD.

Heart failure patients have higher fracture risk

Patients with heart failure may have an increased risk of hip and other orthopedic fractures, suggesting that they should be screened and treated for osteoporosis, a recent study found.

Using a population-based cohort of patients age 65 or older who presented at emergency rooms for cardiovascular disease over a three-year period, researchers compared 2,041 patients with a new diagnosis of heart failure (HF) with a control group of 14,253 patients with non-HF cardiovascular diagnoses. In the year following the ER visit, 4.6% of the HF patients sustained an orthopedic fracture (1.3% sustained hip fractures), compared with 1% of the control group (0.1% hip fractures). The study was published online Oct. 20 by the American Heart Association journal Circulation.

The mechanism linking heart failure and fractures is unclear, said the authors in an AHA news release. They speculated that possible reasons for the association might be elevation of the parathyroid hormone as heart failure worsens; poor adherence to strict diets prescribed for heart failure patients (such as insufficient vitamin D); and lack of exercise. The findings highlight that many older adults are not getting adequate screening and/or treatment for osteoporosis, they said.

Intestinal Clostridium difficile not always linked to antibiotics

Contrary to common belief, community-acquired Clostridium difficile infections develop even in the absence of prior exposure to antibiotics, according to a study published in the October Canadian Medical Association Journal. Researchers urged physicians to test for the infection in all patients who have severe diarrhea, particularly when it requires a hospital visit.

The study relied on two health databases to perform a matched, nested case-control study of elderly patients admitted to a hospital with community-acquired C. difficile infection. For each of the 836 cases, the researchers first selected 10 controls and determined the proportion of cases that occurred without prior antibiotic exposure. They then estimated the risk related to exposure to different antibiotics and the duration of increased risk.

The study found that the highest risk of C. difficile infection from antibiotic use happens in the month following treatment and that the risk declines significantly after 45 days. For the eight-year study period, researchers identified 5,673 hospital admissions for which C. difficile-associated diarrhea was listed as the primary diagnosis. Of these, 836 cases met their definition of community-acquired C. difficile infection. About half of the patients admitted to a hospital because of community-acquired C. difficile infection had no recent antibiotic exposure.

The relative risk of C. difficile infection associated with antibiotic exposure declined from 15.4 about 20 days after exposure to 3.2 at 45 days after exposure. Use of a proton pump inhibitor was associated with increased risk, as was concurrent diagnoses of inflammatory bowel disease, irritable bowel syndrome and renal failure.

The study's findings are limited, according to an editorial, because of narrow inclusion criteria. For instance, the study population was restricted to patients age 65 or older with at least one prior hospital admission in the previous eight years.

Stress tests often skipped before elective PCI

Less than half of Medicare patients with stable coronary artery disease have documentation of ischemia by noninvasive stress testing prior to elective percutaneous coronary intervention (PCI), according to a retrospective, observational study published in the Oct. 15 Journal of the American Medical Association.

This finding is in direct opposition to guidelines for PCI published jointly by the American College of Cardiology, the American Heart Association and the Society for Cardiovascular Angiography and Intervention. The guideline states that for patients with stable angina, any vessels to be dilated must have a shown association with a moderate to severe degree of ischemia on noninvasive testing.

Researchers analyzed 23,887 Medicare claims and 1,630 private insurance claims. They found that 45% of the entitlement program patients underwent stress testing in the three months before angioplasty and that 34% of the non-Medicare beneficiaries underwent stress testing within 12 months of their PCI.

Women, patients treated by physicians under age 40, and patients treated by physicians who perform large numbers of angioplasties were less likely to have test-confirmed ischemia. Patients over age 85 and those with concomitant heart conditions such as congestive heart failure or chronic obstructive pulmonary disease were also less likely to undergo a pre-PCI stress test. Conversely, black patients and those with a history of chest pain were more likely to have a stress test before undergoing angioplasty.

The study revealed regional distinctions in pre-PCI stress testing as well, with physicians in the Midwest and Northeast most likely to order stress tests.

The authors point out that elective angioplasty has increased by 300% during the past decade and has accounted for at least 10% of the increase in Medicare spending since the mid- 1990s. Current proposals to restructure Medicare payments to reward hospitals and physicians who adhere to guidelines would improve the safety and delivery of health care to Medicare beneficiaries, the authors said.

Movement instead of bed rest may improve prognosis after ICU stay

Getting ICU patients out of bed and moving soon after admission leads to shorter hospital stays and may reduce long-term complications, according to a review in the Oct. 8 Journal of the American Medical Association.

Deep sedation and bed rest have recently become common practice for patients on mechanical ventilators. However, there is evidence to suggest that bed rest might be contributing to prolonged neuromuscular complications experienced by many patients following an ICU stay. To examine that question, researchers at Johns Hopkins University looked at 24 studies focusing on ICU patients with sepsis, multiorgan failure or prolonged mechanical ventilation and found that the mean duration of mechanical ventilation after awakening was longer in patients with vs. without weakness (18 vs. 8 days; P =0.03).

The review found that some ICUs introduced aspects of physical medicine and rehabilitation within days of admission and that early rehabilitation therapy appeared to help patients regain their ability to ambulate and conduct activities of daily living. One study included in the review suggested that some activity, such as sitting, is feasible and safe in mechanically ventilated patients with an endotracheal tube. Minimizing sedation and focusing on recovery and rehabilitation issues were key success factors for early mobilization, the review found. However, the authors noted that early rehabilitation in the acute ICU setting is relatively new and that large, randomized trials are needed to evaluate the safety and benefits of these strategies.

The author noted that Johns Hopkins has instituted a new model of care within its medical ICU that includes stopping bed rest as a default order with admission; establishing reduced sedation and bed rest guidelines for consultation with physical and occupational therapists as well as physical medicine, rehabilitation and neurology; and adding multidisciplinary training and education regarding reductions in heavy sedation and improved attempts at rehabilitation for ICU patients.

Whole-leg and two-point ultrasound equal in DVT diagnosis

Diagnosis of deep vein thrombosis (DVT) is as effective via two-point ultrasound as it is with whole-leg ultrasound, according to a prospective study.

In the study, researchers randomized 2,098 patients to either two-point or whole-leg ultrasonography. Symptomatic venous thromboembolism occurred in 7 of 801 patients in the two-point group and in 9 of 763 patients in the whole-leg group. The three-month incidence of objectively confirmed VTE in patients with an initial normal diagnostic ultrasound was similar in the two groups. The findings appeared in the Oct. 8 Journal of the American Medical Association.

Researchers said two observations were particularly noteworthy. First, detecting isolated calf DVT may not be as relevant as previously thought, since the long-term outcomes of the groups were similar even though isolated calf DVT was initially more prevalent in the whole-leg group. Secondly, proximal DVT always involved the common femoral vein, the popliteal vein, or both, suggesting that the superficial and deep femoral veins are usually not worth investigating.

The authors concluded that either strategy can be appropriate depending on the circumstances. Two-point ultrasound is simple, convenient and widely available but requires repeat testing in one-quarter of patients. Whole-leg ultrasound provides results in one day but may be more expensive and may expose patients to the risk of anticoagulation because the procedure often is not available after hours or on weekends.

An editorial said the results of the trial show that whole-leg ultrasonography has little advantage, unless anticoagulant therapy for isolated calf DVT is preferable to repeating two-point ultrasonography a week later.

ED unit improves outcomes by sending overflow to inpatient hallways

Emergency patients moved from the emergency department to inpatient units' hallways had less than half the mortality and intensive care unit admission rates than patients boarded in normal rooms, a recent study reported.

Study results of 57,487 patients admitted to the hospital from the emergency department during a four-year study period were presented at the annual meeting of the American College of Emergency Physicians. Admitted patients were moved to inpatient hallways if they were stable, there were more than three admitted patients already boarded in the emergency department, and there was no space to see incoming emergency patients.

Researchers assessed admissions to Stony Brook University Hospital between January 2004 and January 2008. Although patients sent to inpatient hallways had longer wait times from triage to admission, their mortality rates were 1.1%, compared with 2.5% for patients admitted to normal rooms. Further, ICU admissions were higher in the standard bed admissions at 6.9% vs. 2.6% of patients admitted to inpatient hallways.

According to the Robert Wood Johnson Foundation, which profiled the effort, William Beaumont Hospital in Royal Oak, Mich., reduced crowding and wait times in the emergency department via a new triage system. The system quickly prescreens and categorizes patients before sending them to one of three treatment areas to be more fully triaged. Meanwhile, at the Regional Medical Center at Memphis, Tenn., 60% of all medical/ surgical patients are now discharged from an eight-bed area dedicated to providing discharge instructions and resources for inpatients to assist in preparation for their home care. This provides an inpatient bed more rapidly and has had a significant effect on decreasing ED throughput time.

Smoking cessation programs effective if continued after discharge

Smoking cessation programs for hospitalized patients are effective, but only if they are maintained for at least a month after discharge, a new review found.

The review included 33 randomized and quasi-randomized trials of smoking cessation interventions that began during hospitalization. Researchers found the programs that included supportive contacts for more than one month after discharge increased the percentage of patients who were nonsmoking six to 12 months later by 65%. Shorter interventions, both counseling and pharmacotherapy, showed no benefit.

There was also an indication that programs were particularly effective when provided to patients admitted for cardiovascular disease and when they included nicotine replacement therapy in addition to counseling, but neither of those findings reached the level of statistical significance. The study was published in the Oct. 13 Archives of Internal Medicine.

Study authors noted that the counseling interventions in the included studies were usually delivered by research nurses or trained counselors and that the results might be difficult for clinical staff to replicate. They did conclude that the results of the review support the decision by the Joint Commission and CMS to include a tobacco measure in the national hospital quality-of-care standards. Based on the study, the current quality measure could reasonably be expanded to apply to all hospitalized smokers and strengthened to require that smoking interventions begun in the hospital continue after discharge, the authors said.

Dual purpose recurrent stroke study reveals similar risk with all interventions

Neither aspirin plus extended-release dipyridamole (ASA-ERDP) nor clopidogrel is any better or worse at reducing the risk of recurrent stroke, according to a randomized, industry-supported study published in the Sept. 18 New England Journal of Medicine. In another arm of the same study, also published in the journal, researchers found that the angiotensin-receptor blocker telmisartan failed to lower the rate of stroke recurrence, though it did lower blood pressure.

In the Prevention Regimen for Effectively Avoiding Second Strokes (PRoFESS) trial, 20,332 patients from 695 centers in 35 countries, with a recent history of ischemic stroke, were randomized to either 25 mg of aspirin plus 200 mg of extendedrelease dipyridamole twice daily or to 75 mg of clopidogrel daily.

Patients were followed for 2.5 years, and researchers found that the risk of recurrent stroke or a major hemorrhagic event was similar: 1194 in the ASA-ERDP cohort vs. 1156 among the clopidogrel subjects.

In the antihypertensive arm of the trial, the PRoFESS investigators randomized 10,146 subjects to 80 mg daily of telmisartan and 10,186 subjects to placebo approximately two weeks after an ischemic stroke. In addition to the study medications, patients also received hypertension medication deemed appropriate by the investigators. The primary outcome was recurrent stroke.

Stroke recurrence rates did not differ significantly between the groups after 30 months, although blood pressure was lower among those on telmisartan. Mean blood pressure at the start of the study was 144.1 mm Hg systolic and 83.8 mm Hg diastolic. The between-group difference in diastolic blood pressure favoring telmisartan was 2.9 mm Hg at one month, 2.2 mm Hg at one year and 1.6 mm Hg by the end of the study. The results suggest that improvement in a risk factor does not necessarily result in a patient benefit, according to an observation in Journal Watch Cardiology.

The antiplatelet portion of the PRoFESS study was originally supposed to compare clopidogrel plus aspirin with aspirin plus extended-release dipyridamole. The design was changed, however, when the Management of Atherothrombosis with Clopidogrel in High-Risk Patients with Recent TIA or Ischemic Stroke (MATCH) trial showed an increased risk of bleeding with the combination of clopidogrel and aspirin. Subjects who were originally assigned to the clopidogrel plus aspirin cohort had been treated for up to 8 months before the protocol was adjusted.

Study of contrast agents in kidney patients shows little difference

Hydration with sodium bicarbonate did not produce better outcomes than hydration with sodium chloride in patients with moderate to severe renal dysfunction who were undergoing coronary angiography, according to a randomized study reported in the Sept. 3 Journal of the American Medical Association.

Investigators randomized 353 patients (mean age 71) with stable renal disease who were undergoing coronary angiography at a single U.S. center and had an estimated glomerular filtration rate of 60 mL/min per 1.73 m2 or less and one or more of the following conditions: diabetes mellitus, history of congestive heart failure, hypertension, or age older than 75 years. Patients were randomized to receive either sodium chloride or sodium bicarbonate administered at the same rate-3 mL/kg for one hour before angiography, 1.5 mL/kg during the procedure and for four hours afterward.

The primary end point of a 25% or greater decrease in estimated GFR occurred in 14.6% of patients in the sodium chloride group and 13.3% in the sodium bicarbonate, a non-statistically significant difference. There was no distinct difference in the rate of death, dialysis, heart attack or cerebrovascular event in either group during the follow-up period which started 30 days after exposure to the contrast agent and extended to six months.

One difference noted by investigators was the incidence of contrast-induced nephropathy, which was significantly higher at 22.2% in the patients who underwent angiography for acute coronary syndrome indications vs. 7.3% in patients who underwent angiography for indications other than acute coronary syndrome.

Unfractionated heparin may decrease septic shock mortality

Intravenous unfractionated heparin (UFH) is associated with reduced mortality in patients with septic shock, according to a retrospective, propensity matched Canadian cohort study published in the November Critical Care Medicine.

The study included 2,326 patients age 18 or above who were diagnosed with septic shock and admitted to intensive care units between May 1989 and July 2005. The primary study outcomes were 28-day mortality and mortality stratified by illness severity. Researchers assessed the safety of heparin administration by comparing rates of gastrointestinal hemorrhage, intracranial hemorrhage and the need for allogeneic transfusion.

The mean duration of heparin therapy was 4.7 days, and low-dose prophylactic heparin was administered to 73.7% of patients in the control group within 48 hours of shock. Systemic heparin therapy was associated with decreased 28-day mortality, with a 44.2% survival rate, in comparison to a matched control group, which had a 40.1% survival rate. Among patients having the highest severity of illness, heparin administration was associated with a clinically and statistically significant reduction in 28-day mortality, with a 69% survival rate, compared with 56% in the matched control group.