ArticleTrials2021
Protocol for the Metformin Aneurysm Trial (MAT): a placebo-controlled randomised trial testing whether metformin reduces the risk of serious complications of abdominal aortic aneurysm.
Article in Trials, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 papers.
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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.
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Who cites it
9 citing papers in PubMed, 26 citations in OpenAlex.
- Evidence of a Protective Effect of Metformin on Abdominal Aortic Aneurysm Risk: Insights From an Observational Study and Mendelian Randomisation Analysis Using Putative Metformin Targets.Annals of human genetics · 2026 · on this mapObservational
- Abdominal aortic aneurysm progression: A review of preclinical and clinical data.Clinical research in cardiology : official journal of the German Cardiac Society · 2026Review
- Metformin Use and Long-term Outcomes Including Aneurysm Sac Dynamics Following EVAR for Infrarenal Abdominal Aortic Aneurysm: "A Retrospective Study".Journal of endovascular therapy : an official journal of the International Society of Endovascular Specialists · 2026Article
- Metformin and beyond: glucose-lowering therapy as a potential modulator of abdominal aortic aneurysm growth and stability- systematic review with narrative synthesis.Cardiovascular diabetology. Endocrinology reports · 2026Review
- Metformin and Risks of Aortic Aneurysm and Aortic Dissection: A Mendelian Randomization Study.Reviews in cardiovascular medicine · 2025Article
- The Impact of Diabetes Mellitus and Metformin Use on Outcomes After Endovascular Aneurysm Repair.Journal of clinical medicine · 2025Article
- Association between diabetes status and long-term outcomes following open and endovascular repair of infrarenal abdominal aortic aneurysms.Journal of vascular surgery · 2024Article
- Pathogenesis and management of abdominal aortic aneurysm.European heart journal · 2023Review
- Protection of diabetes in aortic abdominal aneurysm: Are antidiabetics the real effectors?Frontiers in cardiovascular medicine · 2023Review
Corrections and comments
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Authors and funding
11 authors at 8 institutions in 3 countries.
Funding
Abstract
backgroundMultiple observational studies have associated metformin prescription with reduced progression of abdominal aortic aneurysm (AAA). The Metformin Aneurysm Trial (MAT) will test whether metformin reduces the risk of AAA rupture-related mortality or requirement for AAA surgery (AAA events) in people with asymptomatic aneurysms.
methodsMAT is an international, multi-centre, prospective, parallel-group, randomised, placebo-controlled trial. Participants must have an asymptomatic AAA measuring at least 35 mm in maximum diameter, no diabetes, no contraindication to metformin and no current plans for surgical repair. The double-blind period is preceded by a 6-week, single-blind, active run-in phase in which all potential participants receive metformin. Only patients tolerating metformin by taking at least 80% of allocated medication will enter the trial and be randomised to 1500 mg of metformin XR or an identical placebo. The primary outcome is the proportion of AAA events defined as rupture-related mortality or need for surgical repair. Secondary outcomes include AAA growth, major adverse cardiovascular events and health-related quality of life. In order to test if metformin reduced the risk of AAA events by at least 25%, 616 primary outcome events will be required (power 90%, alpha 0.05). DISCUSSION: Currently, there is no drug therapy for AAA. Past trials have found no convincing evidence of the benefit of multiple blood pressure lowering, antibiotics, a mast cell inhibitor, an anti-platelet drug and a lipid-lowering medication on AAA growth. MAT is one of a number of trials now ongoing testing metformin for AAA. MAT, unlike these other trials, is designed to test the effect of metformin on AAA events. The international collaboration needed for MAT will be challenging to achieve given the current COVID-19 pandemic. If this challenge can be overcome, MAT will represent a trial unique within the AAA field in its large size and design.
trial registrationAustralian Clinical Trials ACTRN12618001707257 . Registered on 16 October 2018.
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Registered trials
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