Julia Ferrari, MD, Department of Neurology at the St. John's of God Hospital, Vienna, Austria, discusses her paper "Early clinical worsening in patients with TIA or minor stroke," which was recently published in Neurology® (2010;74:136-141). She spoke with José G. Merino, MD, Science Editor of AAN.com.
AAN.com: Can you summarize the methodology and major findings of your study?
Ferrari: We wanted to assess the rate of and the predictors for early clinical worsening in patients with transient ischemic attack (TIA) or minor stroke in a large nationwide survey of Austrian stroke units. We studied 2,101 patients with TIA and 6,185 with minor stroke (i.e., those having an NIH Stroke Scale score between one and three). We focused on TIA and minor stroke because it is sometimes difficult to differentiate both conditions in the acute phase. The average length of stay in the stroke unit was two days for patients without deterioration and four days for patients with deterioration. Evaluation was done according to standardized protocols, yet choice of examination was at the discretion of the treating physician. We found that 4.5 percent of patients who presented to the hospital with TIA or minor stroke worsened, with a decline of at least two points on the NIH Stroke Scale. Predictors for early clinical worsening included diabetes, hypertension, a higher ABCD2 score, the stroke mechanism, acute infection, and cardiac decompensation. Our findings show that it is important to hospitalize patients with TIA and stroke to identify the mechanism for their stroke and to prevent and treat cardiac and infectious complications.
AAN.com: What is the ABCD2 score?
Ferrari: The ABCD score is a prognostic score for short-term risk of stroke after TIA. The original parameters considered were Age, Blood pressure at admission, Clinical symptoms, and Duration of symptoms. In 2007, the score was validated and another factor, a history of Diabetes (hence ABCD2), was added. The score ranges from 0 to 7, with higher scores indicating a higher risk of stroke. All patients with a score of 4 or higher should be admitted to a stroke unit. While the ABCD2 score has been validated only for TIA patients, our study suggests that it is also useful in patients with minor stroke.
AAN.com: Did admissions to a stroke unit and clinical worsening have an impact on outcome?
Ferrari: Because ours is a registry of acute stroke units, we only have short-term outcome data. Clinical worsening was associated with a poorer short-term (90 day) outcome. Several studies show that treatment in a stroke unit reduces the risk of death by almost 20 percent at a median time of one year. Stroke unit care is also associated with a lower rate of recurrent stroke at four years.
AAN.com: Why do infections have such a significant effect on clinical deterioration?
Ferrari: We all know from our clinical practice that when stroke patients have an infection, rehabilitation measures are delayed, and this leads to worse outcomes. Acute infections may increase the risk of a subsequent myocardial infarction and stroke. No data exists so far on their effect on TIA and minor stroke. As atherosclerosis is an inflammatory disease and parameters of systemic inflammation are associated with macro- and microangiopathy, it is very tempting to speculate that the atherosclerotic lesion leading to the TIA or minor stroke are very vulnerable to further noxious—especially inflammatory—stimuli.
AAN.com: Is the evaluation and treatment of patients with mild stroke or TIA standardized across stroke units in Austria?
Ferrari: In Austria, virtually all patients with TIA and minor stroke who come to medical attention are admitted to a hospital. The aim is to admit all these patients to stroke units, but capacity is limited. Evaluation and treatment of patients with TIA and minor stroke is standardized across stroke units in Austria according to local and European guidelines.
AAN.com: As clinicians, how should we approach patients with mild stroke or TIA?
Ferrari: Transient ischemic attack and minor stroke are associated with a substantial short-term risk of recurrent stroke and thus are increasingly recognized as an unstable condition requiring full medical attention. We think that all these patients should be admitted to a stroke unit to reduce recurrence rates and improve outcome. The ABCD2 score seems to be a good tool to identify patients at the highest risk of recurrence. Patients with acute infection and cardiac decompensation also require full medical attention in the acute phase. Due to the low bleeding risk in patients with TIA or minor stroke, a more aggressive therapy seems to be justified, but further randomized controlled trials are necessary to make a proof of concept.
AAN.com: Please tell us about the Austrian Stroke Unit Registry.
Ferrari: Since 2003, a growing number of Austrian Stroke Units have documented stroke relevant data to a national registry. The registry is serviced by the BIQG, a business unit of Gesundheit Österreich GmbH (GÖG) and was founded in cooperation with the Austrian Society of Stroke Research (ÖGSF). Currently, 31 stroke units participate actively in the registry and we aim to eventually include all Austrian Stroke Units. Data are prospectively collected and entered online anonymously and are password secured. The register contains epidemiological, clinical, diagnostic and therapeutic data as well 90-day outcomes. We defined the parameters of the data bank, and markers of quality in 2002. We divided the level of fulfillment of these indicators of quality into a minimum level and a target level, and stroke units are encouraged to reach the target levels. The participating centers can access their own data and compare them with anonymized data of other centers. The aim of this benchmarking is to ensure that a comparable level of quality is achieved in any region of Austria. Staff from all stroke units meet regularly to discuss how the data collection and quality can be improved. We also carry out scientific projects, like the one we published, and arrange possible international collaborations.
AAN.com: How is stroke care organized in Austria?
Ferrari: Stroke units in Austria are structured as "comprehensive stroke units" with acute treatment and early rehabilitation patients cared for in the same neurological ward, providing all Austrians with access to the two major therapeutic approaches: thrombolysis and specialized stroke care. One should be aware that the concept of "comprehensive stroke units" is used differently in different countries. In Austria, like in Norway or Sweden, we put emphasis on the integration of acute therapy and rehabilitation. In other countries, like the United States, the term Comprehensive Stroke Centers (CSC) is used to indicate the availability of interventional therapies and neurointensive care.
Our goal is to ensure that all people can reach such a stroke unit within at least 60 minutes, and preferably within 45 minutes. In the next few years, the number of stroke units will increase to 40. Stroke units have been exclusively established in neurological wards. All stroke units in Austria, independent of the general status of the hospital (university clinic, hospital in a rural area) fulfill the same criteria (medical staff, equipment etc) and are localized in neurological departments.
Dr. Merino performed a one-time consultation with staff from Bell, Falla and Associates.