Evidence map›Paper›PMID 41749263›Full record

Trial reportTrials2026

Factors associated with adherence to allocated treatment in the ASCEND trial: a mail-based randomised trial of aspirin and of omega-3 fatty acid supplementation in people with diabetes.

Vichithranie W Madurasinghe, Marion Mafham, Georgina Buck, Louise Bowman, Jane Armitage

Abstract readLetterRandomized Controlled Trial
In one paragraph

Trial report in Trials, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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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

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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

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5 · Who and what money

Authors and funding

5 authors.

Vichithranie W MadurasingheClinical Trial Service Unit and Epidemiological Studies Unit, Oxford Population Health, Richard Doll Building, Old Road Campus, Oxford, OX3 7LF, UK. vichithranie.madurasinghe@ndph.ox.ac.uk.
Marion MafhamClinical Trial Service Unit and Epidemiological Studies Unit, Oxford Population Health, Richard Doll Building, Old Road Campus, Oxford, OX3 7LF, UK.
Georgina BuckClinical Trial Service Unit and Epidemiological Studies Unit, Oxford Population Health, Richard Doll Building, Old Road Campus, Oxford, OX3 7LF, UK.
Louise BowmanClinical Trial Service Unit and Epidemiological Studies Unit, Oxford Population Health, Richard Doll Building, Old Road Campus, Oxford, OX3 7LF, UK.
Jane ArmitageClinical Trial Service Unit and Epidemiological Studies Unit, Oxford Population Health, Richard Doll Building, Old Road Campus, Oxford, OX3 7LF, UK.

Funding

Bayer and Solvay Pharmaceuticals (subsequently Abbott, and now Mylan) funding for drug packagingBayer and Solvay Pharmaceuticals (subsequently Abbott, and now Mylan) the Clinical Trial Service Unit & Epidemiological Studies Unit (CTSU) at the University of Oxford received study drugBritish Heart Foundation 2015-2019 (SP/14/3/31114)British Heart Foundation followed by two renewals of the grant in 2009-2013 (SP/08/010/259)British Heart Foundation University of Oxford received a Special Project Grant from 2003 to 2008 (SP/03/002)Cancer Research UK Epidemiological Studies Unit (CTSU) at the University of Oxford supported by this funder.Cancer Research UK Some study staff at the Clinical Trial Service UnitHealth Data Research UK Epidemiological Studies Unit (CTSU) at the University of Oxford is the recipientHealth Data Research UK the Clinical Trial Service UnitMedical Research Council Epidemiological Studies Unit (CTSU) received funding the UK Medical Research CouncilMedical Research Council the Clinical Trial Service Unit
6 · The paper itself

Abstract

introductionASCEND assessed the effects of randomisation to aspirin versus placebo and, separately omega-3 fatty acid (FA) supplementation versus placebo on vascular events in 15480 adults with diabetes using mail-based remote methods. This analysis investigates factors associated with adherence to the allocated treatments.

methodsAdherence was estimated from the 6-monthly follow-up forms and the supply of study treatment packs. A binary adherence variable, full versus less than full adherence during the period at risk of a serious vascular event (SVE), was investigated using logistic regression. Potential predictors of adherence considered were sex, age at randomisation, Hospital Frailty Risk Score, ethnicity, Townsend index, smoking status, type of diabetes, predicted 5-year vascular risk, number of other medications reported at study entry and treatment allocation.

resultsSeven thousand, three hundred twelve (47.2%) participants were fully adherent to aspirin/placebo and 8937 (57.7%) were fully adherent to omega-3 FA/placebo while at risk of a SVE. Women were less likely to be fully adherent than men (aspirin randomisation: 2509 [43.3%] vs. 4803 [49.6%]; OR, 0.73; 95% CI: 0.68 to 0.80; P < 0.0001; omega-3 FA randomisation: 3035 [52.4%] vs. 5902 [61.0%]; OR, 0.67; 95% CI: 0.61 to 0.72; P < 0.0001) and adherence decreased with increasing frailty (trend p-value < 0.0001), smoking (p-value < 0.0001), vascular risk score (p-value < 0.0001) and deprivation (trend p-value = 0.0211, p = 0.0011).

conclusionWe show this large, mail-based trial has comparable adherence with less streamlined trials in similar populations. In ASCEND, women and those with higher levels of frailty, smoking and vascular risk score had poorer adherence to trial medication. Trialists should consider strategies to improve adherence in these participant groups.

Indexed as

AspirinDietary SupplementsFatty Acids, Omega-3Medication AdherencePlatelet Aggregation InhibitorsPostal ServiceAgedFemaleHumansLogistic ModelsMaleMiddle AgedRisk FactorsSex FactorsTime FactorsTreatment OutcomeAspirinFatty Acids, Omega-3Platelet Aggregation InhibitorsAdherenceAspirinCardiovascular diseaseDiabetesOmega-3 fatty acidsRandomised controlled trial

Identifiers

PMID41749263
PMCPMC12947497

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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 OpenQuestion graph.