Benefit of thrombolysis for stroke is maintained around the clock: results from the SITS-EAST Registry

The outcome of thrombolysis for early morning and sleep time strokes may be worse because of uncertainty of stroke onset time or differences in logistics. The aim of the study was to analyze if stroke outcome after intravenous thrombolysis differs depending on time of day when the stroke occurs.

The data collected in the Safe Implementation of Treatments in Stroke - Eastern Europe (SITS-EAST) Registry between September 2000 and December 2011 were used. Strokes were categorized as night-time 00:00-07:59, day-time 08:00-15:59 and evening-time 16:00-23:59 and were compared in terms of several outcome measures. All results were adjusted for baseline differences.

A total of 8878 patients were enrolled: 18% had night-time, 54% day-time and 28% evening-time strokes. Onset-to-treatment time in patients with night-time strokes was 10 min longer than in day-time and evening-time strokes (P < 0.001). Symptomatic intracerebral hemorrhage by ECASS II definition occurred in 5.6%, 5.6% and 5.3% (adjusted P = 0.41) of the night-time, day-time and evening-time stroke patients, respectively; by SITS definition it occurred in 2.5%, 1.9% and 1.3% (adjusted P = 0.013) and by NINDS definition in 7.8%, 7.6% and 7.5% (adjusted P = 0.74). Patients with night-time, day-time and evening-time strokes achieved modified Rankin Scale score 0-1 in 33%, 31%, 31% (adjusted P = 0.34) and 0-2 in 52%, 51%, 50% (adjusted P = 0.23), and 13%, 15%, 16% respectively of patients died (adjusted P = 0.17) by 3 months.

The time when stroke occurs (day versus evening versus night) does not affect the outcome after thrombolysis despite the fact that patients with night-time strokes have worse time management.