Mobile Stroke Units Shown to Improve Outcomes and Reduce Disability Among Stroke Patients

March 17, 2021—Stroke patients treated via a mobile stroke unit (MSU) received clot-busting medications faster and more often and recovered significantly better than patients who received regular emergency care by standard ambulance, according to findings from the ongoing, national BEST-MSU study presented as a late-breaking science presentation at the American Stroke Association’s (ASA’s) International Stroke Conference 2021, held virtually March 17-19, 2021.

The medical teams that are on board MSUs—special ambulances equipped to diagnose and treat stroke quickly—can treat a patient with an ischemic stroke right away with tissue plasminogen activator (tPA).

James C. Grotta, MD, Principal Investigator of the BEST-MSU study commented in ASA’s press release, “Our goal in this study was to treat patients on the MSU within an hour of the onset of their stroke symptoms, and we were gratified that one-third of the patients were actually treated within that time frame. Our study confirmed that patients who are treated early benefit from a complete reversal of stroke symptoms and avoidance of disability. This suggests that in the first hour after a stroke occurs, the brain is not yet irreversibly damaged and is very amenable to effective treatment.” Dr. Grottta is the Director of Stroke Research at the Clinical Institute for Research and Innovation at Memorial Herman—Texas Medical Center in Houston, Texas.

As reported in the ASA announcement, the BEST-MSU investigators examined data from 1,047 patients who experienced an ischemic stroke and were eligible for tPA treated at seven centers in the United States (Houston, Texas; Aurora, Colorado; New York, New York; Indianapolis, Indiana; Los Angeles, California; Memphis, Tennessee; and Burlingame, California) between 2014 and 2020.

Comparing outcomes of stroke patients brought to the emergency department by MSU (n = 617) versus those who arrived by standard emergency medical services (n = 430), the investigators found the following:

• Overall, 97% of patients transported by an MSU received tPA compared to 80% of those brought to the emergency department by a regular ambulance.
• One-third of the patients treated by an MSU were treated within 1 hour after the onset of stroke symptoms, compared to 3% of patients transported by a standard ambulance.
• 53% of the patients treated by an MSU made a complete recovery from the stroke after 3 months versus 43% of the patients treated by a standard ambulance.

Dr. Grotta stated, “Our results mean that, on average, for every 100 patients treated on an MSU rather than standard ambulance, 27 will have less final disability and 11 of the 27 will be disability free. But for this to happen, patients, caregivers, and bystanders need to recognize the signs of stroke and call 9-1-1 immediately.”

He continued, “More widespread deployment of MSUs may have a major public health impact on reducing disability from stroke. Although MSUs are costly to equip and staff, they reduce the time to treatment. We also expect that more treatment via MSUs can reduce the need for downstream utilization of long-term care.”

As noted in the ASA announcement, more research is ongoing by Grotta and his team to assess health care utilization over the entire year following their patients’ strokes, which will enable a better idea of the cost-effectiveness of MSU implementation on a wider scale. Additionally, the American Heart Association’s 2019 Recommendations for the Establishment of Stroke Systems of Care suggest reimbursement is an issue that warrants further investigation before widespread use of MSUs is likely.