In the Literature: HM-Related Research You Need to Know

The Hospitalist. 2011 May;2011(05):

May 1, 2011 | The Hospitalist

Heather L. Davidson, MD ; Melissa Hagman, MD ; Elliot S. Jerud, MD ; Mehraneh Khalighi, MD ; Anna S. Loge, MD ; Andrew White, MD ; Anneliese M. Schleyer, MD, MHA, FHM ; University Of Washington

Synopsis: Data from the New York Statewide Planning and Research Cooperative System identified 30,947 adult patients who were hospitalized with acute stroke over a two-year period. Mean age of patients was 73. Thirty-day all-cause mortality was compared between stroke centers and all other acute-care hospitals. Secondary outcomes were one-day, seven-day, and one-year all-cause mortality. To adjust for unmeasured confounders, the analyses accounted for distance to the nearest stroke center relative to the distance to the nearest acute-care hospital.

Almost half the patients in this study were admitted to stroke centers, where they had an adjusted absolute risk reduction in 30-day mortality of 2.5%. Seven-day mortality was reduced 1.3% and one-year mortality was reduced 3.0%. These findings were statistically significant.

There were no differences in one-day mortality, 30-day readmission rates, or rates of discharge to skilled nursing facilities between hospital designation.

The study was not designed to identify which elements of a certified stroke center contribute to the mortality benefit and did not account for stroke severity. Results may not be generalizable beyond New York state.

Bottom line: Admission to an acute-stroke center is associated with a modest reduction in mortality.

Citation: Xian Y, Holloway RG, Chan PS, et al. Association between stroke center hospitalization for acute ischemic stroke and mortality. JAMA. 2011;305(4):373-380.

Mortality from MRSA Pneumonia Increases with Higher Vancomycin Minimum Inhibitory Concentration

Clinical question: Does vancomycin minimum inhibitory concentration (MIC) affect mortality due to healthcare-associated pneumonia (HCAP), ventilator-associated pneumonia (VAP), and hospital-acquired pneumonia (HAP) from methicillin-resistant Staphylococcus aureus (MRSA)?

Background: S. aureus is considered vancomycin-susceptible if the MIC is ≤2 mg/mL. Mortality from MRSA bacteremia increases as vancomycin MIC rises. The effect of higher vancomycin MICs on outcomes in MRSA pneumonia is not known.

Study design: Prospective cohort study.

Setting: Four academic centers in Kentucky, Ohio, Michigan, and Florida.

Synopsis: One hundred fifty-eight patients with HCAP, VAP, or HAP based on American Thoracic Society/Infectious Disease Society of American (ATS/IDSA) definitions and ≥1 MRSA-positive blood or respiratory culture were identified from the prospectively collected Improving Medicine through Pathway Assessment of Critical Therapy in Hospital-Acquired Pneumonia (IMPACT-HAP) database. All were treated with a regimen including vancomycin based on 2005 ATS/IDSA guidelines.

Vancomycin MIC was ≤1 mg/mL in 27% of MRSA isolates; 1.5 mg/mL in 55%; and ≥2mg/mL in 18%. Overall, all-cause 28-day mortality was 32%. After correcting for confounding factors, such as age and comorbid illnesses, all-cause 28-day mortality was higher in patients with higher vancomycin MICs (adjusted odds ratio of death 2.97 per 1 mg/mL increase in vancomycin MIC). Heteroresistance to vancomycin was present in 21% of MRSA isolates but was not associated with an increase in mortality.

Bottom line: Death due to MRSA HCAP, VAP, and HAP increases as the vancomycin MIC increases, even with MICs within the susceptible range.

Citation: Haque NZ, Zuniga LC, Peyrani P, et al. Relationship of vancomycin minimum inhibitory concentration to mortality in patients with methicillin-resistant Staphylococcus aureus hospital-acquired, ventilator-associated, or health-care-associated pneumonia. Chest. 2010;138(6): 1356-1362.

Clinical Short

ORAL APIXABAN MIGHT BE EFFECTIVE IN THROMBOEMBOLISM PROPHYLAXIS IN ELECTIVE HIP SURGERIES

In a randomized, double-blinded, double-dummy study of 3,866 patients undergoing elective hip surgery, prophylaxis with apixaban was associated with lower rates of VTE (ARR 2.5 percentage points) than enoxaparin without increased bleeding.

Citation: Lassen MR, Gallus A, Raskob GE, Pineo G, Chen D, Ramirez LM for the ADVANCE-3 Investigators. Apixaban versus enoxaparin for thromboprophylaxis after hip replacement. N Engl J Med. 2010;363:2487-2498.

More Frequent In-Center Hemodialysis Improves Outcomes

Clinical question: Does more frequent hemodialysis reduce mortality, improve cardiovascular outcomes, and improve quality of life in patients undergoing maintenance hemodialysis?