Mobile Stroke Unit vs Usual Care and Functional Outcomes in Acute Ischemic Stroke

Mobile stroke unit (MSU) use, compared with usual care, is associated with an approximate 65% increase in odds of an excellent outcome and a 30-minute reduction in onset-to-intravenous thrombolysis (IVT) times without safety concerns in patients with acute ischemic stroke. These findings were published in JAMA Neurology.

The findings are based on a systematic review and meta-analysis of all randomized clinical trials (RCTs) and controlled studies that compared MSU with usual care in patients with acute ischemic stroke.

The study authors searched MEDLINE, Cochrane Library, and Embase for articles published from 1960 through 2021 and included controlled studies comparing MSU deployment and usual care for prehospital management of adult patients with suspected acute ischemic stroke of less than 6-hours duration.

The primary end point was excellent outcome at 90 days (modified Rankin Scale [mRS] score of 0 to 1).

The meta-analysis included 14 articles, of which 4 reported results of 3 RCTs, 2 were from large, prospective, nonrandomized intervention studies with blinded assessment of functional outcome, and 8 were from other observational studies.

Analysis of 5 studies with 3228 patients indicated that MSU was superior to usual care for an excellent outcome in adjusted analysis (pooled odds ratio [OR], 1.64; 95% CI, 1.27-2.13; P <.001; I² = 48%) and crude analysis (pooled OR, 1.37; 95% CI, 1.19-1.58; I² = 0%; P <.001).

In a sensitivity analysis of all patients regardless of final diagnosis and for whom 90-day mRS scores were available, MSU use was still significantly associated with an excellent outcome (pooled crude OR, 1.37; 95% CI, 1.21-1.56; P <.001; I² = 0).

For reduced disability, the pooled common OR was 1.39 (95% CI, 1.14-1.70; P =.001; I² = 0%) in adjusted analysis and 1.30 (95% CI, 1.12-1.50; P =.001; I² = 21%) in unadjusted analysis. For good outcome, the corresponding pooled crude OR was 1.25 (95% CI, 1.09-1.44; P =.001; I² = 0%).

Regarding the proportion of IVT in patients with acute ischemic stroke, the pooled crude OR for MSU vs usual care was 1.83 (95% CI, 1.58-2.12; P <.001; I² = 13%). For the proportion of golden-hour thrombolysis among IVT-treated patients, the pooled crude OR was 7.71 (95% CI, 4.17-14.25; P <.001; I² = 75%). The pooled median reduction in onset-to-IVT time was 31 minutes (95% CI, 23-39; P <.001; I² = 47%).

All-cause mortality at 7 days from 9 studies with 8599 patients was not different between the treatment groups (pooled crude OR, 0.74; 95% CI, 0.51-1.09; P =.13; I² = 33%).

The researchers noted that the meta-analysis involves limited available literature, and the assessed functional outcomes were largely based on 2 nonrandomized, large, prospective controlled studies that used alternating weeks and availability of MSU for allocation of patients. In addition, most of the data were derived from studies in metropolitan areas with well-established emergency medical services.

“These results should help guideline writing committees and decision makers to shape the future of prehospital stroke care,” wrote the investigators. “However, MSU implementation is associated with costs and requires optimal integration into regional emergency response services. Further studies will be needed to determine in which local environments the deployment of MSUs would be the most useful.”

Disclosure: Some of the study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.

Reference

Turc G, Hadziahmetovic M, Walter S, et al. Comparison of mobile stroke unit with usual care for acute ischemic stroke management: a systematic review and meta-analysis. JAMA Neurol. Published online February 7, 2022. doi: 10.1001/jamaneurol.2021.5321