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Therapeutic Hypothermia in Acute Ischemic Stroke—a Systematic Review and Meta-Analysis


Purpose of Review

Therapeutic hypothermia (TH) in stroke demonstrates robust neuroprotection in animals but clinical applications remain controversial. We assessed current literature on the efficacy of TH in ischemic stroke.

Recent Findings

We conducted a meta-analysis comparing TH versus controls in studies published until June 2019. Controlled studies reporting on ≥ 10 adults with acute ischemic stroke were included. Primary outcome was functional independence (modified Rankin Scale [mRS] ≤ 2). Twelve studies (n = 351 TH, n = 427 controls) were included. Functional independence did not differ between groups (RR 1.17, 95% CI 0.93–1.46, random-effects p = 0.2). Five studies reported individual mRS outcomes and demonstrated a shift toward better outcome with TH (unadjusted cOR 1.57, 95% CI 1.01–2.44, p = 0.05). Overall complications were higher with TH (RR 1.18, 95% CI 1.06–1.32, p < 0.01).


We did not observe an overall beneficial effect of TH in this analysis although some studies showed a shift toward better outcome. TH was associated with increased complications.

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Papers of particular interest, published recently, have been highlighted as: • Of importance

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A.M.K. receives funding from the Alberta Innovates—Health Solutions MD/PhD studentship.

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Correspondence to Mohammed A. Almekhlafi.

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(DOC 64 kb)

Supplementary Figure1

Funnel plot of the 14 studies of TH in acute ischemic stroke. Each grey circle on the plot represents an individual study in the meta-analysis. The two diagonal lines represent the expected distribution of studies while the horizontal line indicates the log of the pooled odds ratio (PDF 117 kb)


(DOCX 58 kb)

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Kuczynski, A.M., Marzoughi, S., Al Sultan, A.S. et al. Therapeutic Hypothermia in Acute Ischemic Stroke—a Systematic Review and Meta-Analysis. Curr Neurol Neurosci Rep 20, 13 (2020).

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