Evidence map›Paper›PMID 42226567›Full record

SynthesisEuropean journal of neurology2026

The Epidemiology and Clinical Presentation of the Acute Imbalance Syndrome (AIS)-A Systematic Review and Meta-Analysis.

Konstantin Schmidt, Andreas Zwergal, Diego Kaski, Alexander Andrea Tarnutzer

Abstract readMeta-AnalysisSystematic Review
In one paragraph

Synthesis in European journal of neurology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors.

Konstantin SchmidtFaculty of Medicine, University of Zurich, Zurich, Switzerland.
Andreas ZwergalDepartment of Neurology, LMU University Hospital, LMU Munich, Munich, Germany.
Diego KaskiSENSE Research Unit, Department of Clinical and Movement Neurosciences, UCL, London, UK.
Alexander Andrea TarnutzerFaculty of Medicine, University of Zurich, Zurich, Switzerland.ORCID https://orcid.org/0000-0002-6984-6958

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectivesThe acute imbalance syndrome (AIS) refers to acute-onset and persistent vertigo, dizziness and/or imbalance without nystagmus, reflecting a subset of the acute vestibular syndrome (AVS) with or without nystagmus. While AVS with nystagmus is well characterized and the approach to these patients is validated, much less is known about patients presenting with AIS. This systematic review synthesizes current epidemiologic and clinical evidence on AIS.

methodsMEDLINE and Embase (2000-2024) were searched for English-language original articles addressing acute imbalance, vertigo/dizziness and reporting on nystagmus and/or AVS/AIS. Two reviewers independently screened articles and extracted predefined parameters. The review was registered with PROSPERO (CRD42024623068).

resultsForty studies (n = 11,731 patients) were included, with 2730 patients being classified as AVS. Prevalence of AVS (with/without nystagmus) amongst all acutely dizzy patients was 16.4% and 50.5%, respectively, in two studies. 49.4% of central AVS cases were classified as AIS. Whereas AIS presentation was rare in AICA strokes (9%), fractions reached 40% (PICA), 57% (SCA), and 62% (PCA) for other vascular territories. Data on underlying causes in noncentral AIS was limited, with dysautonomia, drug intoxication, and heart disease being most frequently identified.

conclusionsWith almost 50% of central AVS cases presenting as AIS, this emphasizes the importance of selecting bedside testing appropriately, focusing on algorithms such as STANDING or graded truncal instability. Patients presenting with AIS have a distinct differential diagnosis than those with AVS with nystagmus, mostly due to the distribution of noncentral causes. Promoting awareness of AIS and its diagnostic approach should be prioritized in emergency and acute neurological settings.

Indexed as

DizzinessNystagmus, PathologicVertigoVestibular DiseasesAcute DiseaseHumansSyndromeacute imbalance syndromedizzinessepidemiologygait ataxianystagmusvertigo

Identifiers

PMID42226567
PMCPMC13240050

What Socratic holds

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.