TOPLINE:

In patients with acute ischaemic stroke receiving reperfusion therapies such as mechanical thrombectomy (MT) or intravenous thrombolysis (IVT), an elevated neutrophil‑to‑lymphocyte ratio before treatment was associated with poor functional outcomes, whereas a higher lymphocyte‑to‑monocyte ratio was linked to better functional outcomes after MT.

METHODOLOGY:

• Researchers conducted a systematic review and meta-analysis to assess whether venous blood cell ratios measured before treatment could predict functional outcomes in patients with acute ischaemic stroke following reperfusion therapies.
• They identified 30 studies (20 on MT and 10 on IVT) after a literature search across various databases on November 30, 2024.
• Venous blood samples were collected before reperfusion therapy, and associations between blood cell ratios, such as neutrophil‑to‑lymphocyte, lymphocyte-to-monocyte, platelet-to-lymphocyte, platelet-to-neutrophil, and monocyte-to-lymphocyte ratios, and functional outcomes were analysed.
• Functional outcomes were assessed using the modified Rankin Scale, with scores of 3-6 defined as poor outcomes.

TAKEAWAY:

• At 3‑month follow‑up, an elevated neutrophil‑to‑lymphocyte ratio was associated with 9% higher odds of poor functional outcomes after MT (pooled odds ratio [OR], 1.09; 95% CI, 1.04-1.15) and 11% higher odds after IVT (pooled OR, 1.11; 95% CI, 1.01-1.21).
• Patients with a higher lymphocyte-to-monocyte ratio had 21% lower odds of poor functional outcomes after MT (pooled OR, 0.79; 95% CI, 0.67-0.92); however, no significant association was observed between the lymphocyte-to-monocyte ratio and functional outcomes after IVT.
• Those with an elevated neutrophil‑to‑lymphocyte ratio had 5% higher odds of mortality after MT (pooled OR, 1.05; 95% CI, 1.01-1.08); however, no significant association was found between the neutrophil‑to‑lymphocyte ratio and mortality in those who received IVT.
• Other venous blood cell ratios, such as platelet-to-lymphocyte, platelet-to-neutrophil, and monocyte-to-lymphocyte ratios, were not significantly associated with functional outcomes after MT or IVT therapies.

IN PRACTICE:

"Our findings indicate that among the venous blood cell ratios examined, the NLR [neutrophil‑to‑lymphocyte ratio] stands out as the most robust and consistent predictor of both poor functional outcome and mortality following acute reperfusion therapies," the authors wrote.

"Its reliability across both MT and IVT cohorts, paired with its easy, cheap, and quick measurement and widespread availability in routine clinical practice, supports its potential use as a practical biomarker worldwide in all hospital settings for early risk stratification in patients with AIS [acute ischaemic stroke]," they added.

SOURCE:

This study was led by István Szegedi, Department of Neurology, University of Debrecen, and Zsolt Barnabás Éles, Lendület "Momentum" Hemostasis and Stroke Research Group of the Hungarian Academy of Sciences, both in Debrecen, Hungary. It was published online on January 13, 2026, in Neurology and Therapy.

LIMITATIONS:

The observational nature of the included studies may have introduced residual confounding and limited causal interpretations. Stroke aetiology was not assessed because most included studies lacked subtype‑specific outcome data. The predominance of single-centre studies may have limited the generalisability of the findings.

DISCLOSURES:

This study received support from the MTA-DE Lendület "Momentum" Hemostasis and Stroke Research Group of the Hungarian Academy of Sciences and the Hungarian Research Network Cerebrovascular Research Group. The authors reported having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.