Evidence map›Paper›PMID 40641043›Full record

Trial reportInternational journal of stroke : official journal of the International Stroke Society2026

Optimal markers of treatment response to vasodilatory drugs in small vessel disease: An OxHARP trial analysis.

Alastair J S Webb, Karolina Feakins, Amy Lawson, Catriona Stewart, James Thomas, Osian Llwyd

Abstract readRandomized Controlled Trial
In one paragraph

Trial report in International journal of stroke : official journal of the International Stroke Society, 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

6 authors.

Alastair J S WebbDepartment of Brain Sciences, Imperial College London, London, UK.ORCID 0000-0002-0630-8204
Karolina FeakinsWolfson Centre for Prevention of Stroke and Dementia, University of Oxford, Oxford, UK.ORCID 0000-0003-4049-2364
Amy LawsonDepartment of Basic and Clinical Neuroscience, King's College London, London, UK.ORCID 0000-0001-8684-4922
Catriona StewartSchool of Medicine, University of St. Andrews, St. Andrews, UK.ORCID 0000-0002-7618-7882
James ThomasWolfson Centre for Prevention of Stroke and Dementia, University of Oxford, Oxford, UK.
Osian LlwydWolfson Centre for Prevention of Stroke and Dementia, University of Oxford, Oxford, UK.ORCID 0000-0001-9104-3222

Funding

Wellcome TrustWellcome Trust 206589/Z/17/Z
6 · The paper itself

Abstract

BACKGROUND AND

aimsVasodilating drugs targeting the endothelium could reduce long-term harms due to cerebral small vessel disease (cSVD) but there are no commonly accepted methods to measure short-term disease activity or drug response. In the OxHARP clinical trial, we determined the most sensitive physiological markers of treatment response to sildenafil versus placebo on either transcranial ultrasound (TCD) or magnetic resonance imaging (MRI), and their validity compared to disease severity and other measures of other physiological mechanisms.

methodsIn the OxHARP double-blind, randomized, placebo-controlled crossover trial we measured aortic blood pressure, mean flow velocity (MFV), cerebral pulsatility, cerebrovascular conductance index (CVCi = MFV/aortic mean BP), cerebral perfusion (pcASL-MRI) and cerebrovascular reactivity to inhaled CO2 on TCD (CVR-TCD) and MRI in white (CVR-WM), gray (CVR-GM) and white matter hyperintensities (CVR-WMH). Effects of 3 weeks of sildenafil were compared to placebo. Validity of markers were determined by between-visit repeatability (intraclass correlation coefficient (ICC)); associations with CVR-TCD, CVR-WMH and CVR-GM; associations with other markers; the magnitude of response, and sensitivity, to sildenafil.

resultsIn 69 participants, repeatability was greatest for MFV, pulsatility, CVCi and CVR-WMH (ICC > 0.8), very good for CVR-TCD and GM-perfusion (ICC > 0.7), and good for CVR-GM (ICC > 0.6). CVR-TCD was associated with CVR on MRI (CVR-WMH: r

conclusionsMultiple markers were associated with cSVD, but no single marker reflected all physiological drug effects. CVCi and gray matter perfusion on MRI were the most sensitive markers of disease activity and drug response, although CVR indices may be more specific for endothelial dysfunction.

Indexed as

Cerebral Small Vessel DiseasesSildenafil CitrateVasodilator AgentsAgedBiomarkersCerebrovascular CirculationCross-Over StudiesDouble-Blind MethodFemaleHumansMagnetic Resonance ImagingMaleMiddle AgedTreatment OutcomeUltrasonography, Doppler, TranscranialBiomarkersSildenafil CitrateVasodilator Agentscerebral pulsatilitycerebrovascular reactivitySmall vessel disease

Identifiers

PMID40641043
PMCPMC12743133

What Socratic holds

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LicenceCC BY
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Registered trials

None linked

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.