1. Chimowitz MI, Lynn MJ, Howlett-Smith H, et al. Comparison of warfarin and aspirin for symptomatic intracranial arterial stenosis. N Engl J Med. 352:1305-16.
This is the first prospective study comparing antithrombotic therapies for patients with atherosclerotic stenosis of major intracranial arteries. This multicenter, NINDS-sponsored, placebo-controlled, blinded study randomized 569 patients to aspirin (650 mg twice daily) or warfarin (initially 5 mg daily, titrated to achieve an INR of 2.0–3.0) and followed them for nearly 2 years. The study was terminated early over safely concerns about patients in the warfarin group. Baseline characteristics between the 2 groups were not significantly different. Warfarin was not more effective than aspirin in its effect on the primary endpoints of ischemic stroke, brain hemorrhage, or vascular death other than from stroke (as defined in the study protocol). However, major cardiac events (myocardial infarction or sudden death) were significantly higher in the warfarin group, and major hemorrhage (defined as any intracranial or systemic hemorrhage requiring hospitalization, transfusion, or surgical intervention) was also significantly higher in the warfarin group. The authors note the difficulty maintaining the INR in the target range (achieved only 63.1 % of the time during the maintenance period, an observation in line with other anticoagulation studies). In an accompanying editorial, Dr. Koroshetz of the stroke service at the Massachusetts General Hospital also observed that difficulties in achieving the therapeutic goal with warfarin could have impacted the results. The authors also note that the dose of aspirin employed in this study is somewhat higher than in previous trials. Nevertheless, until other data emerge, this investigation’s results favor aspirin in preference to warfarin for this high-risk condition.
2. Cornish PL, Knowles, SR, Marchesano R, et al. Unintended medication discrepancies at the time of hospital admission Arch Intern Med. 2005;165:424-9
Of the various types of medical errors, medication errors are believed to be the most common. At the time of hospital admission, medication discrepancies may lead to unintended drug interactions, toxicity, or interruption of appropriate drug therapies. These investigators performed a prospective study to identify unintended medication discrepancies between the patient’s home medications and those ordered at the time of the patient’s admission and to evaluate the potential clinical significance of these discrepancies.
This study was conducted at a 1,000-bed tertiary care hospital in Canada on the general medicine teaching service. A member of the study team reviewed each medical record to ascertain the physician-recorded medication history, the nurse-recorded medication history, the admission medication orders, and demographic information. A comprehensive list of all of the patient’s prescription or nonprescription drugs was compiled by interviewing patients, families, and pharmacists, and by inspecting the bottles. A discrepancy was defined as any difference between this comprehensive list and the admission medication orders. These were categorized into omission or addition of a medication, substitution of an agent within the same drug class, and change in dose, route, and frequency of administration of an agent. The medical team caring for the patient was then asked whether or not these discrepancies were intended. The team then reconciled any unintended discrepancies. These unintended discrepancies were further classified according to their potential for harm by 3 medical hospitalists into Class 1, 2, 3, in increasing order of potential harm. One hundred fifty-one patients were included in the analysis. A total of 140 errors occurred in 81 patients (54%). The overall error rate was 0.93 per patient. Of the errors, 46% consisted of omission of a regularly prescribed medication, 25% involved discrepant doses, 17.1% involved discrepant frequency, and 11.4% were actually incorrect drugs. Breakdown of error severity resulted in designation of 61% as Class 1, 33% as Class 2, and 5.7% as Class 3. The interrater agreement was a kappa of 0.26. These discrepancies were not found to be associated with night or weekend admissions, high patient volume, or high numbers of medications.