Literature at a Glance
A guide to this month’s studies.
- Score predicts risk of intracerebral hemorrhage after thrombolysis.
- Trigylcerides and stroke-risk predictors.
- PPI use and risk of community-acquired pneumonia.
- Clopidogrel before coronary intervention might improve outcomes.
- High-dose clopidogrel after coronary intervention is beneficial.
- B-type natriuretic peptide level and sepsis.
- Thrombolytic use in pulmonary embolism.
- Hospitalists and ED patient flow.
Clinical question: Is there a simple scoring tool that will predict the risk of intracerebral hemorrhage (ICH) following IV tissue-plasminogen activator (t-PA) in ischemic strokes?
Background: The use of t-PA in acute ischemic stroke (AIS) is about 2% to 4%, due in part to fear of conversion of an ischemic event to an ICH. Several studies using t-PA after AIS have identified risk factors for ICH; however, none has looked at the cumulative risk and prognosis for an individual candidate based on these factors.
Study design: Retrospective, observational cohort study.
Setting: The National Institute of Neurological Disorders and Stroke Trials 1 and 2, and consecutive patients treated at Beth Israel Deaconess Medical Center, Boston.
Synopsis: After an extensive literature review, a five-point scale to determine the risk of hemorrhage after t-PA (HAT) was developed using the top four predictive factors based on odds ratios. These included the National Institutes of Health Stroke Scale (NIHSS), presence and extent of hypodensity on initial CT scan, history of diabetes, and high baseline serum glucose. The predictive value of this scale was tested against two independent cohorts of patients with AIS treated with IV t-PA. The HAT scale was able to reasonably predict both the risk of ICH following t-PA and the functional outcome at 90 days. Higher scores on the scale tended to do worse, especially scores of three or more. Its retrospective nature and small number of patients experiencing ICH limit this study.
Bottom line: The HAT score is a quick bedside tool that can help in the counseling of patients and families in conjunction with the risks and benefits of t-PA after ischemic stroke.
Citation: Lou M, Safdar A, Mehdiratta M, et al. The HAT Score: a simple grading scale for predicting hemorrhage after thrombolysis. Neurology. 2008;71:1417-1423.
Clinical question: Is there a correlation between nonfasting triglyceride levels and ischemic stroke?
Background: Most individuals are in a nonfasting state, with the exception of several hours prior to breakfast. Fasting cholesterol levels exclude most remnant lipoproteins, which might play a role in early atherosclerotic disease. Increased levels of triglycerides in a nonfasting state indicate the presence of these remnants.
Study design: Prospective, population-based cohort study.
Setting: The Copenhagen City Heart Study.
Synopsis: The study included 13,956 individuals between the ages of 20 and 93 with a follow-up period of up to 31 years. Cholesterol levels were checked during four evaluation periods: 1976-1978, 1981-1983, 1991-1994, and 2001-2003. Eighty-two percent of the participants had eaten a meal within three hours of the blood draw; the other 18% had eaten more than three hours prior to the draw. The study showed an association between increasing nonfasting triglyceride levels and a step-wise increase in the risk of ischemic stroke. The highest risk came in individuals with nonfasting triglyceride levels > 443mg/dl, which was associated with a three- to fourfold greater risk of ischemic stroke. The study was limited in that it evaluated a homogenous group of individuals, which may not reflect other racial or ethnic populations.