Luciana Catanese, MD

Gensicke H, Strbian D, Zinkstok SM, Scheitz JF, Bill O, Hametner C, et al. Intravenous Thrombolysis in Patients Dependent on the Daily Help of Others Before Stroke. Stroke. 2016

IV t-PA treatment (IVT) trials have mainly focused on outcomes of acute ischemic stroke (AIS) patients who have the highest potential for recovery (baseline mRS 0-2), leaving several questions unanswered for those who were previously dependent (mRS 3-5).  
In this edition of Stroke, Dr. Gensicke, et al. designed a prospective and explorative multicenter study to address the impact of preexisting dependency on outcomes and complications in a large population of IVT-treated stroke patients. The 3-month mRS score defined outcomes. Data of 7430 patients was prospectively collected from 12 European Centers including 6941 and 486 patients with a baseline mRS 0-2 (independent) and 3-5 (dependent), respectively. The most common causes of pre-existing dependency in order of frequency were dementia (45.6%), degenerative or traumatic bone disease (19.7%), prior strokes (16.6%) and heart diseases (16.6%). Interestingly, previously dependent patients were more often female, had more severe strokes, more vascular risk factors and were more often on antithrombotic medications than the independent ones. Although dependent patients were more likely to die (adjustedOR 2.19) at 3 months, there was no difference in the likelihood of poor outcomes at 3 months or the rate of symptomatic ICH between groups. Unexpectedly, the odds of poor outcome were indeed lower in pre-stroke dependent patients if age and stroke severity were taken into account. Such a finding is likely to be related to the greater capacity of previously independent patients to have poor outcomes (mRS 0-2➞6) compared to previously dependent ones (mRS 3-5➞6) and the lower potential for functional worsening in those already dependent at baseline, rather than a true physiologic effect.

Overall, results of this trial are consistent with prior data that shows that previously dependent patients are sicker at baseline with more comorbidities and prescribed medications, tend to score higher on the NIHSS due to the accumulation of deficits and have a higher overall mortality. However, whether or not dependent patients still benefit from IVT remains unanswered and more research looking into this topic is warranted. In the meantime, IVT should continue to be offered to previously dependent AIS patients.