Evidence map›Paper›PMID 7831623›Full record

Trial reportThorax1994

Effect of acetazolamide and amiloride against sodium metabisulphite-induced bronchoconstriction in mild asthma.

B J O'Connor, C T Yeo, Y M Chen-Worsdell, P J Barnes, K F Chung

Open access · bronzeAbstract readClinical TrialRandomized Controlled Trial
In one paragraph

Trial report in Thorax, 1994. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed
–field-weighted citation impact, top 82% of its field
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

4 citing papers in PubMed, 10 citations in OpenAlex.

  1. Article
  2. Review
  3. Article
  4. Article
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

5 authors at 1 institution in 1 country.

B J O'ConnorDepartment of Thoracic Medicine, National Heart and Lung Institute, Royal Brompton Hospital, London, UK.
C T Yeo
Y M Chen-Worsdell
P J Barnes
K F Chung
Royal Brompton Hospital · GB

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundInhaled frusemide but not bumetanide, another loop diuretic, reduces bronchial responsiveness to sodium metabisulphite (MBS). To investigate whether the effect of frusemide could be mediated through mechanisms other than Na+/K+/Cl- cotransporter inhibition, the effects of amiloride--an inhibitor of sodium channels in the airway epithelium--and of acetazolamide--a specific inhibitor of carbonic anhydrase--against MBS challenge were studied.

methodsIn two separate randomised double blind placebo controlled studies, 10 subjects with mild asthma attended on four separate occasions to inhale 7.5 mg amiloride or matched placebo, and 500 mg acetazolamide or placebo, immediately before MBS challenge. The concentration of MBS required to cause a 20% fall in baseline FEV1 (PC20) was measured.

resultsAmiloride and acetazolamide had no effect on baseline FEV1. Amiloride had no effect against MBS challenge, but acetazolamide increased -log PC20 from a mean (SE) of 0.75 (0.09) to 0.98 (0.06) representing a 0.77 (0.24) doubling dose increase.

conclusionsThese results suggest that carbonic anhydrase activity in the airways, but not sodium flux, modulates bronchial responsiveness to MBS challenge. The action of frusemide is not likely to involve inhibition of carbonic anhydrase activity.

Indexed as

AcetazolamideAdultAmilorideAsthmaBronchial Provocation TestsBronchoconstrictionCarbonic AnhydrasesDouble-Blind MethodFemaleForced Expiratory VolumeHumansMaleMiddle AgedSodiumSulfitesAcetazolamideAmilorideCarbonic AnhydrasesSodiumsodium metabisulfiteSulfites

Identifiers

PMID7831623
PMCPMC475268
OpenAlexW2164630293

What OpenQuestion holds

Textmetadata
Read underepoch 390

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 OpenQuestion graph.