Recent Research

Scores for predicting pneumonia and hemorrhage after ischemic stroke, update on managing unstable cardiac conditions, and more.


Scores help predict pneumonia, hemorrhage risk after ischemic stroke

Two scores can help clinicians predict the risk of pneumonia and symptomatic intracranial hemorrhage after ischemic stroke.

To derive the score for predicting symptomatic intracranial hemorrhage (sICH), researchers used data on 10,242 patients from Get With the Guidelines-Stroke. All had received intravenous tissue-type plasminogen activator (IV-tPA) within three hours of ischemic stroke onset from January 2009 to January 2010. Patients were randomly divided into derivation (70%) and validation (30%) cohorts, and multivariable logistic regression was used to identify predictors of IV tPA-related sICH. Results were published in the September Stroke.

Nearly 5% of ischemic stroke patients had sICH within 36 hours. Independent predictors, represented by the acronym GRASPS, were higher blood glucose, Asian race, increasing age, male sex, higher systolic blood pressure at presentation, and severity of stroke at presentation (i.e., higher baseline National Institutes of Health Stroke Scale [NIHSS] score). The model was externally validated in National Institute of Neurological Disorders and Stroke trial patients.

The clinical risk prediction tool is available online. It should help clinicians, patients and families understand the risks of tPA, but shouldn't be used to determine which patients would derive the most or least benefit from IV tPA, the authors wrote. Hospitals can also use the score for quality improvement efforts, to see if their actual rate of sICH exceeds the expected rate predicted by the score, they wrote.

To derive the second score for predicting pneumonia, German researchers used 2007-2009 data on 15,335 ischemic stroke patients from the Berlin Stroke Register. They used multivariable logistic regression analyses to identify predictors of post-stroke pneumonia and translate them into a point scoring system, then validated them with an independent cohort of 45,085 ischemic stroke patients from the Stroke Register Northwest-Germany. Results were published in the October Stroke.

The in-hospital, post-stroke pneumonia rate was 7.2%. A 10-point score was derived based on age 75 years or greater, presence of atrial fibrillation, presence of dysphagia, male sex, and stroke severity as measured by the NIHSS. Using this “A2DS2” score, the proportion of pneumonia varied from 0.3% in patients with a score of 0 to 39.4% in patients with a score of 10. The researchers are currently conducting a prospective observational study to test the predictive properties of the A2DS2 score, they said. If validated, it may help with decisions to use prophylaxis in patients deemed high risk for post-stroke pneumonia, they wrote.

Focused update released on management of unstable angina, non-ST-segment-elevation MI

The American College of Cardiology Foundation/American Heart Association recently released a focused update to their guidelines on management of unstable angina and non-ST-segment-elevation myocardial infarction (NSTEMI). The guidelines were originally issued in 2007 and were last updated in March 2011. This update replaces the March 2011 update.

The guideline writing committee looked at research on the newly approved oral P2Y12 receptor inhibitor agents prasugrel and ticagrelor, and offered guidance on how to incorporate them into clinical practice, as well as comparisons of the different agents in various settings. The focused update covers the following areas:

  • antiplatelet/anticoagulant therapy in patients with likely or definite unstable angina/NSTEMI,
  • timing of discontinuation of P2Y12 receptor inhibitor agents for surgical procedures,
  • initial invasive versus initial conservative strategies,
  • long-term medical therapy and secondary prevention,
  • special considerations in diabetes and chronic kidney disease and
  • quality of care and outcomes for unstable angina/NSTEMI.

The update was published in the Aug. 14 Circulation.

Severe blood conservation didn't harm long-term survival of cardiac surgery patients

Extreme blood management strategies didn't hamper the long-term survival of cardiac surgery patients, according to a study comparing Jehovah's Witnesses to non-Witnesses.

Researchers sought to compare morbidity and survival of cardiac surgery patients who were Jehovah's Witnesses (Witnesses)—and had beliefs that disallow blood transfusion—with those of a matched group who received transfusions. They identified 96,162 patients at the Cleveland Clinic who underwent cardiac surgery between Jan. 1, 1983 and Jan. 1, 2011, and excluded those who underwent ventricular assist device placement or heart transplantation or required extracorporeal membrane oxygenation. After other exclusions, the analysis included 322 Witnesses and 87,453 non-Witnesses. Among non-Witnesses, 38,467 didn't receive transfusions and 48,986 did. Results were published in the Aug. 13/27 Archives of Internal Medicine.

Witnesses had a shorter length of stay and fewer acute complications than matched patients who received transfusions. Comparisons for these two groups were as follows: myocardial infarction, 0.31% for Witnesses vs. 2.8% for non-Witnesses with transfusions (P=0.01); additional operation for bleeding, 3.7% vs. 7.1% (P=0.03); prolonged ventilation, 6% vs. 16% (P<0.001); 50th percentile of intensive care unit length of stay, 25 hours vs. 48 hours (P<0.001); 50th percentile of hospital length of stay, 7 days vs. 8 days (P<0.001); and one-year survival, 95% vs. 89% (P=0.007). Twenty-year survival was similar between groups, as was the risk of in-hospital mortality, stroke, atrial fibrillation and renal failure.

Witnesses who have cardiac surgery distinguish themselves by “specific process-of-care management strategies aimed at avoiding extreme anemia,” the authors noted, such as preoperative use of erythropoietin and iron and B-complex vitamins and intraoperative use of antifibrinolytics. These measures may carry risks, but transfusion carries risks too, and extreme blood management strategies don't appear to make non-transfusion patients less likely to survive long term, they wrote.

An important limitation of the study is that Witnesses who have cardiac surgery are probably a healthier subgroup “because those who are believed by their surgeons to require blood transfusion to survive cardiac surgery presumably never go to the operating room,” an invited commenter wrote. Still, the findings do raise questions as to whether more patients may benefit from strategies that cut down on the use of blood product transfusion—whether Witnesses or non-Witnesses, he concluded.

Heart attacks may lead to PTSD, analysis finds

Posttraumatic stress disorder (PTSD) is relatively common among survivors of acute coronary syndrome (ACS) and is associated with worse outcomes, according to a meta-analysis.

The analysis covered 24 observational cohort studies including more than 2,000 patients who had ACS and were assessed for PTSD at least one month after the event. Overall, 12% of the patients had clinically significant symptoms of PTSD (95% CI, 9% to 16%), although rates varied widely among the studies. The variation could be explained by differing methods of screening, authors said; studies that used a screening questionnaire found higher rates of PTSD than those that used diagnostic interviews.

Three of the studies, totaling about 600 patients, assessed the relationship between PTSD and negative outcomes (mortality and/or ACS recurrence). Combined, the studies indicated a doubling of risk for these negative outcomes associated with clinically significant symptoms of PTSD (risk ratio, 2.00; 95% CI, 1.69 to 2.37). The overall meta-analysis also found that younger age was associated with higher PTSD rates, while a more recent study publication date was associated with lower risk (perhaps due to advances in treatment, the authors said). The results were published in the June PLoS One.

Extrapolating from their findings, study authors calculated that 168,000 ACS patients in the U.S. may develop PTSD each year. Their risk for mortality and recurrence is similar to the increased risk faced by depressed patients, they noted. Although the mechanism for this relationship is not known, increased inflammation associated with PTSD may have a negative effect on the heart, the authors speculated.

They called for additional research into treatments for ACS-induced PTSD, noting that only one treatment study (a trial of cognitive behavioral therapy) was identified in their search. A unified risk stratification strategy, using previously identified risk factors, is also needed, they concluded.

Acadesine doesn't reduce poor outcomes in CABG patients

A randomized controlled trial found acadesine didn't reduce poor outcomes in intermediate- to high-risk patients undergoing coronary artery bypass grafting (CABG), despite an earlier meta-analysis suggesting it would.

From early May 2009 to late July 2010, researchers enrolled patients from 300 sites in seven countries who were undergoing nonemergency CABG with cardiopulmonary bypass and who were at intermediate to high risk of postoperative adverse events. The majority of participants were white men (median age, 66 years) with a history of hyperlipidemia, diabetes, family history of cardiovascular disease, and previous percutaneous coronary intervention. After screening and within 14 days before surgery, patients were randomized to receive acadesine or placebo (saline) intravenously before, during and immediately after CABG. The primary composite end point was occurrence of any of the following during surgery or through postoperative day 28: all-cause death, nonfatal stroke, or the need for mechanical support for severe left ventricular dysfunction (SVLD).

The study, funded by Schering-Plough, was stopped after 3,080 patients of a planned 7,500 had been randomized, because results of a preset futility analysis indicated a very low likelihood of a statistically significant efficacious outcome. The final sample size consisted of 2,986 patients in the intention-to-treat analysis. The primary outcome occurred in 5.1% of patients in the acadesine group and 5.0% in the placebo group (odds ratio, 1.01; P=0.94). There were no differences in key secondary end points measured at 28 days, or in additional exploratory efficacy end points including length of mechanical ventilation, intensive care unit and hospital stay. Results were published in the July 11 Journal of the American Medical Association.

The results, wrote the authors, “illustrate inherent risks of using promising meta-analysis results to plan ‘confirmatory’ clinical trials.” While the dosing regimen was identical to previous trials, the lack of benefit in the current trial could be related to insufficient dosing, they said. While acadesine didn't have an effect on the end point, the study did show that results from CABG have continued to improve—possibly due to improvements in preoperative selection and preparation, intraoperative treatment and postoperative recovery procedures in recent years, they wrote. The study also found that quality of life 28 days after CABG was improved compared to quality of life before the surgery, they added.

ACE inhibitors but not ARBs may decrease pneumonia risk

Angiotensin-converting enzyme (ACE) inhibitors are associated with a decreased risk for pneumonia, but angiotensin receptor blockers (ARBs) are not, a recent study indicated.

Researchers performed a systematic review and meta-analysis of studies published through June 2011 to evaluate the association between ACE inhibitors and ARBs and pneumonia risk. Randomized, controlled parallel trials, cohort studies and case-control studies that had predefined outcomes and examined ACE inhibitors and ARBs as interventions were included. Primary and secondary outcomes were pneumonia incidence and pneumonia-related mortality, respectively.

In included treatment studies, ACE inhibitors and ARBs could be compared with each other or with placebo or another active drug. Included cohort studies could examine community-, institution- or hospital-based populations and needed to determine pneumonia outcomes by patient follow-up. Included case-control studies had to define cases as new-onset pneumonia determined by clinical examination, radiology, or database codes. For the primary outcome, matched controls could not have new-onset pneumonia, while for the secondary outcome, both cases and controls with pneumonia were acceptable. The study results were published online July 11 by BMJ.

A total of 37 studies were included in the analysis. Compared with control treatment and treatment with ARBs, ACE inhibitors were associated with significantly lower risk for pneumonia (odds ratio [OR] compared with control treatment, 0.66 [95% CI, 0.55 to 0.80] and ARBs (combined direct and indirect OR estimate for ARBs, 0.69 [95% CI, 0.56 to 0.85]). This association persisted in patients with stroke, with ORs of 0.46 (95% CI, 0.34 to 0.62) for ACE inhibitors compared with control treatment and 0.42 (95% CI, 0.22 to 0.80) for ACE inhibitors compared with ARBs. A significantly lower risk for pneumonia was seen with ACE inhibitors in Asian patients compared with non-Asian patients (OR, 0.43 vs. 0.82; P<0.001). ACE inhibitors and ARBs had a similar beneficial effect on pneumonia-related mortality compared with control treatments.

The authors noted that although all of the included studies were of good quality, some flaws might have affected their results. Specifically, none of the randomized, controlled trials were designed to determine how ACE inhibitors or ARBs affected pneumonia. They also noted that observational studies formed an important part of their analysis and that they pooled data from studies with different designs, among other limitations. The authors concluded, however, that ACE inhibitors may have an important role in preventing pneumonia but that ARBs do not. “These data may discourage the withdrawal of ACE inhibitors in some patients with tolerable adverse events (namely, cough) who are at particularly high risk of pneumonia,” the authors wrote. They called for further randomized, controlled trials to confirm their conclusions and better quantify the observed effects of ACE inhibitors.

Combination of creatinine and cystatin C more accurate than either alone

Combining creatinine and cystatin C measurements provided a more accurate estimation of glomerular filtration rate (GFR) than using either measurement alone, a recent study found.

Researchers used data from more than 5,000 participants in 13 studies to develop estimating equations for GFR using cystatin C alone and in combination with creatinine. They then used more than 1,000 participants in five studies in which GFR had been measured to validate the equations. Results were published in the July 5 New England Journal of Medicine.

In the validation cohort, the combined cystatin C-creatinine equation showed similar bias to the equations using only one marker, and it was more precise and accurate than either of them. Using the combined equation, only 8.5% of estimates were more than 30% off the measured value, compared to 12.8% and 14.5% with creatinine and cystatin C, respectively.

The combined equation performed better than either of the single-marker ones, study authors concluded. The combined equation was more accurate in patients with a body mass index less than 20 kg/m2, a subgroup in which creatinine-based estimates are less accurate.

However, the results do not suggest that cystatin C should replace creatinine as a marker in clinical practice, according to the authors. Routine use of it could increase laboratory costs, so it may be most useful as a confirmatory test for diagnosis of chronic kidney disease, they said. An accompanying editorial suggested that clinicians also keep in mind the value of presence or absence of albuminuria for diagnosis and staging of chronic kidney disease. The editorialist suggested use of the cystatin C measurement to diagnose patients who have no albumin in the urine and an estimated GFR close to 60 mL/min/1.73 m2 according to creatinine measurement.

Hyperbaric oxygen therapy lowers death rate from necrotizing infections

Hyperbaric oxygen (HBO2) therapy reduced mortality in patients with necrotizing soft-tissue infection (NSTI), but was associated with longer length of stay and greater hospitalization costs, an analysis found.

Researchers used 1988-2009 data from the U.S. National Inpatient Sample to perform a retrospective analysis that compared patients who received HBO2 therapy to those who didn't. The 45,913 patients deemed to have NSTI met the International Classification of Diseases, 9th Edition (ICD-9-CM) codes for necrotizing fasciitis, Fournier's and gas gangrene. In-hospital mortality was the primary outcome; secondary outcomes included discharge status and location, hospital length of stay and total inflation-adjusted hospital charges. Results were published in the July Intensive Care Medicine.

Nearly 1% (n=405) of patients diagnosed with NSTI received HBO2 therapy. These patients had more comorbidities at admission and were more likely to be in a larger, urban hospital; they were less likely to be emergency admissions. They had lower mortality (odds ratio, 0.49; P=0.008) related to NSTI than patients who didn't receive HBO2, but had longer adjusted length of stay (14.3 days vs. 10.7 days; P<0.001) and higher median costs for hospitalization ($52,205 vs. $45,464; P<0.001) Among patients who died in the hospital, the adjusted median duration of survival was 17.1 days for those who received HBO2 therapy versus 8.8 days for those who didn't (P=0.03).

Both groups were equally likely to have a routine discharge and to develop complications related to NSTI.

It wasn't possible to tease out how much of the difference in cost was due to the therapy or due to the longer length of stay of patients who received it, the authors noted. While the therapy takes time, these patients also had more comorbidities, which could have contributed to longer length of stay. Indeed, the fact that this group had more comorbidities makes their lower mortality with treatment more striking, the authors noted.

The results of the study add to evidence supporting the use of HBO2 therapy in patients with NSTI, though a multicenter, randomized controlled trial would be preferable, they concluded. Such a trial would be difficult to conduct, however, given the small number of patients with NSTI in individual institutions. “We conclude that even when taking into account the additional [length of stay] and hospitalization costs, the reduction in mortality associated with HBO2 therapy justifies its use in NSTI,” the authors wrote.

Several types of myocardial dysfunction common in sepsis patients

Myocardial dysfunction is frequent in patients with severe sepsis or sepsis shock, and has a wide spectrum of types, a study found.

In a prospective study, researchers examined 106 patients who were admitted to three ICUs at Mayo Clinic from Aug. 1, 2007 to Jan. 31, 2009. The patients met criteria for new-onset sepsis as defined by the American College of Chest Physicians/Society of Critical Care Medicine Consensus Conference. Severe sepsis was defined as sepsis associated with organ dysfunction, hypoperfusion, or hypotension. All patients enrolled received a transthoracic echocardiographic evaluation within 24 hours of meeting sepsis criteria. Myocardial dysfunction was defined as left ventricular (LV) diastolic, LV systolic or right ventricular (RV) dysfunction. Frequency of myocardial dysfunction was calculated, and mortality rates of those with and without dysfunction were compared.

Sixty-four percent of patients with severe sepsis or septic shock also had myocardial dysfunction. Thirty-seven percent of all sepsis patients had LV diastolic dysfunction, 27% had LV systolic dysfunction and 31% had RV dysfunction. Overall mortality rates were 36% at 30 days and 57% at one year, with no difference in mortality between patients with normal myocardial function and those with dysfunction. Results were published in the July Mayo Clinic Proceedings.

The study confirmed that myocardial dysfunction is frequent in patients with severe sepsis and septic shock and presents in a spectrum that includes LV diastolic, LV systolic and RV dysfunction. As such, the current practice of using decreased LV ejection fraction as the sole criterion for determining cardiac dysfunction in sepsis “is inaccurate and misleading,” the authors wrote. Echocardiography should be used to help to diagnose the specific type of myocardial dysfunction so that patients can be managed appropriately, they suggested.

No harm in early laparoscopic cholecystectomy for mild gallstone pancreatitis

Patients with mild gallstone pancreatitis can safely have a laparoscopic cholecystectomy within 48 hours of admission, and it appears to shorten their length of stay compared to those who wait longer, a study found.

Researchers did a retrospective review of 303 patients from two teaching hospitals in southern California. They sought patients who underwent laparoscopic cholecystectomy (LC) for mild gallstone pancreatitis between 2006 and 2011. The mean patient age was 37 years, and 78.2% of patients were female. Of the 303 patients, 38.6% (n=117) underwent an early LC and 61.4% (n=186) underwent a delayed LC. There were no differences between groups in terms of sex, lab results or vital signs at admission, or Ranson score at admission, though the early LC group was slightly older (40 vs. 35 years; P=0.006). The most common reason for delayed LC was to wait for bilirubin or pancreatic enzyme levels to normalize.

Patients who had early LC had a significantly shorter mean length of stay (LOS) than those who had late LC (3.4 days vs. 6.3 days; P<0.001). The mortality rate was 0% in both groups, and there were no differences between groups in complication rates, readmissions within 30 days, or conversion from LC to open cholecystectomy. There was no difference between groups in use of postoperative endoscopic retrograde cholangiopancreatography (ERCP), though preoperative ERCP use was higher in the delayed LC group (17% vs. 6%; P=0.004). Results were published online July 16 by Archives of Surgery.

The results indicate early LC can safely be performed for mild gallstone pancreatitis without the need for lab values to normalize or clinical symptoms to resolve completely, the authors noted. A potential danger exists for patients identified as having mild pancreatitis whose condition worsens, as research has shown early LC to be harmful in those with serious pancreatitis, they said. However, none of the 303 study patients with mild pancreatitis progressed to severe pancreatitis. “We believe the safety of an early LC lies in the identification and exclusion of patients who may be at risk of progressing to a more severe pancreatitis, such as those with tachycardia, elevated serum urea nitrogen level, or evidence of cholangitis at hospital admission,” they wrote.

Greater sedative use associated with delirium, longer time on mechanical ventilation

Reducing exposure to sedatives among mechanically ventilated patients, both at night and during the day, may improve their outcomes, a study found.

In a prospective cohort study, researchers examined 140 ICU patients at a hospital in Nashville, Tenn. who received mechanical ventilation (MV) for more than 12 hours. They recorded patients' doses of benzodiazepines and propofol every hour, in order to determine whether daytime and/or nighttime increases in dosage were independently associated with delirium, coma and more time on mechanical ventilation. For study purposes, daytime was considered 7 a.m. to 11 p.m. and nighttime was 11 p.m. to 7 a.m. Nighttime dose increases were quantified by subtracting the average hourly daytime dose on the previous day from the subsequent average hourly nighttime dose. Results were published in the October Critical Care Medicine.

Among patients who received sedatives, benzodiazepine doses were increased at night (vs. day) on 40% of patient-days and propofol doses were increased at night on 41% of patient-days. Delirium was present on 33% of patient-days and coma was present on 42% of patient-days. Higher daytime benzodiazepine dosage was independently associated with failed spontaneous breathing trials and extubation, and subsequent delirium (P<0.02 for all), in adjusted models. Nighttime increase in benzodiazepine dose was associated with failed spontaneous breathing trials (P<0.01) and with delirium (P<0.05). Over the first five days of the study, patients spent 75% of their time in delirium or coma.

The study confirms previous findings that benzodiazepines are an independent risk factor for developing delirium during critical illness, but expands the findings by showing the drug increases the odds even when given more than eight hours before delirium assessment. The results argue for wider adoption of structured sedation protocols to reduce total exposure to sedatives, the authors wrote, with particular emphasis on nighttime care.

Risk score helps determine 30-day mortality in patients with cancer and pulmonary embolism

A simple risk score may help determine 30-day mortality risk in patients with cancer and acute pulmonary embolism (PE), a study has found.

Researchers in Spain sought to develop a risk score for 30-day mortality in patients with cancer and PE using data obtainable at PE diagnosis. They randomly allocated consecutive patients from the Computerized Registry of Patients with Venous Thromboembolism (RIETE) to a derivation cohort and an internal validation cohort. An external validation cohort of patients with cancer and acute PE was also used. The study's primary outcome was all-cause mortality 30 days after acute symptomatic PE was diagnosed, while the secondary outcome included all-cause mortality, nonfatal major bleeding or nonfatal recurrent venous thromboembolism in the same time period. Outcomes were compared in the derivation and validation cohorts. The study results were published online July 17 by Chest.

The derivation cohort included 1,048 patients, and the internal validation cohort included 508 patients. Two hundred sixty-one patients were included in the external validation cohort. In the derivation cohort, six variables were found to help predict 30-day mortality risk:

  • age older than 80,
  • heart rate of 110 beats/min or higher,
  • systolic blood pressure less than 100 mm Hg,
  • body weight less than 60 kg
  • recent immobility and
  • presence of metastases.

In the internal validation cohort, the 22.2% of patients classified as low risk by the score had a 30-day mortality rate of 4.4%, compared with 29.9% in the high-risk group. In the external validation cohort, the 18% of patients classified as low risk by the score had a 0% 30-day mortality rate, compared with 19.6% in the high-risk group.

The authors acknowledged that information bias, missing data and residual confounding were possible, among other limitations, and called for further studies that would examine the effective of the prediction model on patient management. However, they concluded that the score they developed could accurately identify patients with cancer and PE who were at low risk for death, and “might facilitate acute management of these patients on an outpatient basis.”

Higher HDL, triglycerides associated with 30-day survival

Patients with lower HDL cholesterol and triglycerides had a higher risk of dying after an ischemic stroke and treatment with intravenous thrombolysis.

In this retrospective study of over 1,800 ischemic stroke patients (all treated with intravenous thrombolysis), researchers identified factors associated with three-month mortality. Patients who died had a median HDL of 1.34 mmol/L (51.82 mg/dl) at presentation compared to 1.40 mmol/L (54.13 mg/dl) in survivors. When triglyceride levels were compared, lower levels were also associated with mortality: a median of 1.00 mmol/L (88.57 mg/dl) in patients who died compared to 1.15 mmol/L (101.86 mg/dl) in those who survived at least three months. Other predictors of mortality were higher NIH Stroke Scale score, age, C-reactive protein and serum creatinine.

Symptomatic intracerebral hemorrhage (ICH) was associated with higher mortality, but not with total cholesterol, LDL, HDL or triglycerides. Thus, the association between low HDL and triglycerides and mortality was not due to ICH, the researchers concluded. They also found that patients who had excellent outcomes at three months after stroke (a modified Rankin score of 0-1) had higher HDL levels at the time of their strokes. The results were published online by Neurology on July 25.

The study couldn't determine the mechanisms behind these associations, the authors acknowledged. One possible explanation for the association between triglycerides and mortality is that lower triglycerides indicate a poor nutritional state. Or, triglycerides may provide a neuroprotective effect against fatty acid neurotoxicity, the authors speculated.

The association between low HDL and mortality (even when controlling for statin use) is novel, but consistent with previous research finding higher mortality in obese patients. There are several mechanisms by which HDL could contribute neuroprotective or vasculoprotective effects, the authors said. HDL also could be a marker for some other factor, such as fitness, since exercise is known to increase HDL levels. More research is needed to understand the mechanism of the association between high HDL and triglycerides and survival after stroke, the authors concluded.

Recommendations on oral antithrombotics to prevent stroke

New oral antithrombotic agents may be reasonable alternatives to warfarin and aspirin for preventing stroke in some patients with nonvalvular atrial fibrillation (AF), according to a science advisory.

The advisory reviewed current guidelines and recent evidence on dabigatran, rivaroxaban and apixaban. After acknowledging the limitations of current knowledge about these new drugs, the expert panel offered the following new recommendations for patients with nonvalvular AF:

  • All three drugs are indicated for stroke prevention in patients with nonvalvular AF, but the selection of an antithrombotic agent should be individualized based on risk factors, cost tolerability, patient preference, potential drug interactions and other clinical characteristics including time in INR therapeutic range if the patient has been taking warfarin.
  • For patients with at least one additional risk factor for stroke and CrCl >30 mL/min, dabigatran 150 mg twice daily is an efficacious alternative to warfarin. For those with lower CrCl (15-30 mL/min), 75 mg may be considered, although its safety and efficacy has not been established. For those with CrCl below 15 mL/min, dabigatran is not recommended.
  • For patients at moderate to high risk of stroke, rivaroxaban 20 mg daily is a reasonable alternative to warfarin. If CrCl is 15 to 50 mL/min, 15 mg may be considered, although its safety and efficacy has not been established. If CrCl is below 15 mL/min, rivaroxaban should not be used.
  • Apixaban 5 mg twice daily is an efficacious alternative to aspirin or warfarin for patients who have at least one additional risk factor and no more than one of the following characteristics: age ≥80, weight ≤60 kg, serum creatinine ≥1.5 mg/dL. For patients meeting two or more of those criteria, a 2.5-mg dose may be considered. However, the safety and efficacy of reduced-dose apixaban in this setting has not been established. Apixaban should not be used if CrCl is <25 mL/min.
  • The safety and efficacy of combining any of these drugs with an antiplatelet agent has not been established.

The advisory was published online Aug. 2 by the American Heart Association and American Stroke Association in Stroke. It was also affirmed by the American Academy of Neurology.

Preop screening detected unknown diabetes in one-fourth of patients

Among elective surgery patients, nearly one-fourth (24%) were diagnosed with previously unknown diabetes or pre-diabetes based on blood tests conducted while they were fasting pre-operatively, researchers found.

To assess whether diabetes testing could be incorporated into the elective surgical work-up, researchers conducted a prospective observational study among 275 patients undergoing elective total knee or hip arthroplasty or elective lumbar decompression and/or fusion who had a preoperative visit between December 2007 and November 2008 at a large Wisconsin academic medical center.

The mean patient age was 60.3 years, and 88% had a body-mass index greater than 25 kg/m2. All of the patients had insurance; 97% had a primary care provider, and 96.6% of patients had seen a primary provider within the past year. Fasting blood glucose was drawn immediately before surgery, and patients with preoperative fasting blood glucose greater than 100 mg/dL had another blood sample taken six to eight weeks postoperatively. Results were in the October Journal of Hospital Medicine.

In the study, 18% of patients had known diabetes or pre-diabetes, and 58% were normoglycemic. The other 24% were found to have previously unrecognized diabetes or impaired fasting glucose. Sixty-four percent of patients with fasting blood glucose greater than 100 mg/dL preoperatively remained elevated at their follow-up visit.

Researchers noted that with more than one million total knee and hip operations done in the U.S. annually, such screening could potentially identify more than a quarter-million previously unknown cases of diabetes or pre-diabetes. Furthermore, considering that 70 million patients undergo ambulatory or inpatient procedures each year, if one quarter of them allowed for easy preoperative testing, more than four million cases of diabetes and impaired fasting glucose could be found annually. Accountable care organizations may encourage such novel interventions, the authors noted.

Researchers added, “Remarkably, this statistic [24%] likely represents a ‘best case scenario,’ as the percent of undiagnosed patients is likely higher in uninsured patients, those without primary care visits, and those hospitalized for emergent or urgent reasons who, by definition, did not have an ambulatory preoperative evaluation, and who may also have greater severity of illness at baseline.”