The AVERT trial found very early mobilisation - such as out-of-bed sitting, standing and walking - within 24 hours of stroke onset and at increased intensity, led to 4% fewer people with good recovery than usual care.
No differences were found in death rates, overall disability scores, or in the time to be able to walk. Most people in this study, even as part of usual care, started mobilising in less than 24 hours.
Guidelines recommend early mobilisation when appropriate and this study may not prompt an immediate change in practice, but does provide clearer evidence that higher intensity early intervention may not be better than more slowly mobilising at around one day after a stroke.
Why was this study needed?
Stroke is the fourth largest cause of death in the UK and the largest cause of complex disability. Each year in England, approximately 110,000 people have a first or recurrent stroke. More than 900,000 people in England are living with the effects of stroke, with half of these being dependent on other people for help with everyday activities.
Early mobilisation – including sitting out-of-bed, standing and walking – is thought to improve outcomes after a stroke. However, definitions of what “early mobilisation” interventions involve vary. Evidence for the effectiveness of early mobilisation is not strong. A 2014 meta-analysis found no significant differences between mobilisation before 24 hours and later mobilisation. The current study was then already underway to determine if earlier and more intensive mobilisation would lead to better outcomes and reduced mortality compared with usual care, and has more than five times the number of participants than the previous small trials combined.
What did this study do?
AVERT was a randomised controlled trial carried out in 56 stroke units across five countries, mainly Australia and the UK. It included 2,104 adults who had been admitted within 24 hours of the onset of their first or recurrent stroke and who could participate in mobilisation. Treatment given to break up any blood clots, called recombinant tissue plasminogen activator (rtPA), was allowed. The study compared an early mobilisation protocol, comprising more frequent (over 30 min per day) out-of-bed activity started on average 18 hours of stroke onset, with usual care, involving less frequent mobilisation (10 min per day) started on average 22 hours post-stroke. Neither the patients nor those assessing the results knew which group the patients had been assigned to, which reduces potential bias.
What did it find?
- 46% of the early mobilisation group compared with 50% of the usual care group made a good recovery three months after the stroke (OR 0.73, 95% CI 0.59 to 0.90). This was defined as no or minimal disability (score 0-2 on the 6 point Rankin scale).
- There was no difference in the time to it took to walk unassisted. In both groups, 50% of people were walking 50 metres unassisted seven days after the stroke and 75% by three months.
- There were no significant differences in the number of deaths or serious side effects, or outcomes for subgroups based on age, stroke severity, stroke type, whether rtPA treatment was given, time to first mobilisation or recruitment region.
What does current guidance say on this issue?
2014 NICE guidance on the early management of stroke recommends that people with acute stroke are sat up and mobilised, “when their clinical condition permits” but does not specify a timeframe, precise mode or duration of mobilisation. NICE recommended that further research be carried out into the safety and effectiveness of early mobilisation versus usual care.
What are the implications?
This trial indicates that early mobilisation four hours earlier and for an average of 30 minutes per day may lead to slightly greater disability than starting more slowly at a median of 22 hours. This potentially has implications for practice because 2014 clinical guidance recommends early mobilisation.
The AVERT trial does not lend any support for starting intensive mobilisation much before 24 hours after a stroke, but mobilising at around that time seems safe in that outcomes in both arms of this trial compare favourably with previous audit results. Few people in this trial started mobilising after 48 hours so no conclusions can be drawn about resting for more than a day after a stroke.
The AVERT Trial Collaboration Group. Efficacy and safety of very early mobilisation within 24 h of stroke onset (AVERT): a randomised controlled trial. Lancet. 2015 Apr 16 [Epub ahead of print].
This project was funded by the National Institute for Health Research HTA Programme (project number 12/01/16).
Lynch E, Hillier S, Cadilhac D. When should physical rehabilitation commence after stroke: a systematic review. Int J Stroke. 2014 Jun;9(4):468-78
NICE. Stroke: Diagnosis and initial management of acute stroke and transient ischaemic attack (TIA). National Institute for Health and Care Excellence: London; 2014.
Stroke Association. State of the nation: Stroke statistics. Stroke Association: London; 2015.
Produced by the University of Southampton and Bazian on behalf of NIHR through the NIHR Dissemination Centre