Long-term effect of intravenous thrombolytic therapy in acute stroke: responder analysis versus uniform analysis of excellent outcome.
BACKGROUND
Knowledge regarding functional improvement over time and long-term outcome after intravenous thrombolysis in acute ischaemic stroke is limited. The aim of this study was to compare a uniform assessment of outcome with an assessment taking the baseline stroke severity into account (responder analysis).


METHODS
Fifty-seven patients were assessed with the modified Rankin Scale at 3, 6 and 12 months and a comparison was made between a uniform assessment and a responder analysis of excellent outcome.


RESULTS
Between 3 and 12 months, 74% of the patients had a stable functional outcome and 22% improved. Excellent outcome at 12 months was similar in the uniform analysis (37%) and the responder analysis (35%). The individual patients having an excellent outcome differed, however, using the two methods. Using a responder analysis the number of patients with excellent outcome decreased in mild stroke patients by 40%, but increased in severe stroke patients by 43%.


CONCLUSIONS
Short-term outcome is sustained at 12 months, but major improvement does not occur between 3 and 12 months. A responder analysis of long-term excellent outcome provided a balanced measure of outcome reflecting the drug-related potential of improvement in all stroke severity subgroups, whereas a uniform analysis provided a measure of outcome mainly in mild stroke patients. These results suggest that a responder analysis should be considered for the assessment of outcome after treatment for acute stroke.
Thomassen
Lars
L
Department of Neurology, Haukeland University Hospital, Bergen, Norway. lars.thomassen@haukeland.no
Waje-Andreassen
Ulrike
U
Naess
Halvor
H
Elvik
May-Karin
MK
Russell
David
D
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003627:Data Interpretation, Statistical; D005260:Female; D005343:Fibrinolytic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D005500:Follow-Up Studies; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000150:complications / Q000188:drug therapy; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D020521:Stroke / Q000188:drug therapy*; D015912:Thrombolytic Therapy; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
D005343:Fibrinolytic Agents