Reference: AAVERT trial (Lancet 2015 July 4;386(9988):46) (level 2 [mid-level] evidence)
Early mobilization (sitting out-of-bed, standing, and walking) is recommended for less severely affected patients after acute stroke to reduce the risk of complications such as pneumonia, deep vein thrombosis, pulmonary embolism, and pressure ulcers (Stroke 2013 Mar;44(3):870). The optimal timing and frequency of early mobilization, however, has not been well-defined. One small randomized trial suggested that mobilization within 52 hours may reduce the risk of life-threatening complications compared to mobilization after 7 days, but the overall complication rate was not significantly different between groups (Clin Rehabil 2012 May;26(5):451). Results of trials examining mobilization within 24 hours have been conflicting. A meta-analysis of 2 small trials found very early mobilization decreased complications and improved independence (Stroke 2010 Nov;41(11):2632), while one small trial published since suggested mobilization within 24 hours might be associated with increased mortality and poorer global function (Stroke 2012 Sep;43(9):2389). To resolve the uncertainty about the impact of early mobilization, a recent randomized trial compared very early mobilization vs. routine mobilization as part of care in the stroke unit in 2,104 adults (mean age 73 years and 61% male) with ischemic or hemorrhagic stroke admitted to the stroke unit within 24 hours of symptom onset.
Very early mobilization began within 24 hours of stroke onset and included at least 3 out-of-bed sessions focusing on sitting, standing, or walking. Usual care varied by treatment location, but thrombolysis with tissue plasminogen activator (tPA) was allowed. Overall, mobilization within 24 hours occurred in 92% of patients randomized to very early mobilization compared to 59% of patients randomized to usual care with a median time to first mobilization of 18.5 hours vs. 22.4 hours, respectively (p < 0.0001). At 3 months post-stroke, 46% of patients with early mobilization and 50% of patients with usual care had a favorable outcome, defined as a modified Rankin Scale score of 0-2 (p = 0.004, NNH 25). These results were consistent, though often not significant, in prespecified subgroup analyses by age, stroke severity, stroke type, recombinant tPA use, and region of recruitment. There were no significant differences in the distribution of patients across all 0-6 point modified Rankin Scale scores, however. There were also no significant differences between groups in mortality, time to walking unassisted, and adverse events.
While previous trials evaluating early mobilization after acute stroke were limited by the small numbers of patients included, the current trial is well powered to detect small differences in patient outcomes after acute stroke. Indeed, it is more than 10 times the size of all previous mobilization trials combined. One drawback of the present trial, however, was that the median time to first mobilization was less than 24 hours in both randomized groups. This reflects the fact that the trials included patients with both mild strokes and severe strokes, in fact approximately 40% of patients in both groups were able to walk independently at baseline. Nonetheless, the very early mobilization group had their median time to first mobilization approximately 4 hours before the usual care group and there was an absolute difference of 33% in the rate of patients being mobilized within 24 hours. These differences in mobilization did not benefit the earlier mobilization group, and very early mobilization may have even negatively impacted global functioning at 3 months. Finally, unlike in previous trials, this trial found that early mobilization did not decrease adverse events, including immobilization-related serious adverse events. Overall, the results of this trial suggest that benefits previously associated with early mobilization do not require mobilization to begin within 24 hours. This suggests current recommendations may need to be updated.
For more information see the Stroke (acute management) topic in DynaMed.