Evidence map›Paper›PMID 37157006›Full record

Trial reportBreast cancer research and treatment2023

Metformin, placebo, and endocrine therapy discontinuation among participants in a randomized double-blind trial of metformin vs placebo in hormone receptor-positive early-stage breast cancer (CCTG MA32).

Dawn L Hershman, Bingshu E Chen, Claire Sathe, Wendy R Parulekar, Julie Lemieux, Jennifer A Ligibel, Karen A Gelmon, Timothy J Whelan, Pamela J Goodwin

Abstract readRandomized Controlled Trial
PubMed Publisher
In one paragraph

Trial report in Breast cancer research and treatment, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers.

0numbers the graph read from it
0cells of the map it votes in
5citing papers in PubMed
1.8field-weighted citation impact, top 14% 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

5 citing papers in PubMed, 7 citations in OpenAlex.

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

9 authors at 7 institutions in 2 countries.

Dawn L HershmanHerbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY, USA. dlh23@columbia.edu.ORCID http://orcid.org/0000-0001-8807-153X
Bingshu E ChenCanadian Cancer Trials Group, Queen's University, Kingston, ON, Canada.
Claire SatheHerbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY, USA.
Wendy R ParulekarCanadian Cancer Trials Group, Queen's University, Kingston, ON, Canada.
Julie LemieuxCHU de Québec-Université Laval, Québec, QC, Canada.
Jennifer A LigibelDana-Farber Cancer Institute, Boston, MA, USA.
Karen A GelmonBC Cancer Agency, University of British Columbia, Vancouver, BC, Canada.
Timothy J WhelanJuravinski Cancer Centre, McMaster University, Hamilton, ON, Canada.
Pamela J GoodwinLunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON, Canada.
Columbia University Irving Medical Center · USQueen's University · CABC Cancer Agency · CADana-Farber Cancer Institute · USJuravinski Cancer Centre · CAMount Sinai Hospital · CAUniversité Laval · CA

Funding

Canadian Cancer Society Research Institute 021039Division of Cancer Prevention, National Cancer Institute CA077202
6 · The paper itself

Abstract

backgroundThe MA32 study investigated whether 5 years of metformin (versus placebo) improves invasive disease-free survival in early-stage breast cancer (BC). Non-adherence to endocrine therapy (ET) and medications for chronic conditions is common and increases with drug toxicity and polypharmacy. This secondary analysis evaluates rates and predictors of early discontinuation of metformin, placebo, and ET among participants with HR-positive BC.

methodsPatients with high-risk non-metastatic BC were randomized to 60 months of metformin (850 mg BID) or placebo BID. Patients were administered bottles of metformin/placebo every 180 days. Metformin/placebo adherence was defined as a bottle dispensed at month 48 or later. The ET adherence analysis included patients with HR-positive BC who received ET with start and stop date reported, with adherence defined as > 48 months of use. Associations of covariates with study drug and ET adherence were examined using multivariable models.

resultsAmong the 2521 HR-positive BC patients, 32.9% were non-adherent to study drug. Non-adherence was higher among patients on metformin vs placebo (37.1% vs 28.7%, p < 0.001). Reassuringly, ET discontinuation rates were similar between treatment arms (28.4% vs 28.0%, p = 0.86). Patients who were non-adherent to ET were more likely to discontinue study therapy (38.8% vs 30.1%, p < 0.0001). In a multivariable analysis, study drug non-adherence was increased with metformin vs placebo (OR: 1.50, 95% CI 1.25-1.80; p < 0.0001); non-adherence to ET (OR: 1.47, 95% CI 1.20-1.79, p < 0.0001); grade 1 or greater GI toxicity during the first 2 years; lower age; and higher body mass index.

conclusionWhile non-adherence was higher among patients on metformin, it was still considerable among patients on placebo. Reassuringly, treatment arm allocation did not impact ET adherence. Attention to global medication adherence is needed to improve BC and non-oncological outcomes in cancer survivors.

trial registrationClinicalTrials.gov: NCT01.

Indexed as

Breast NeoplasmsMetforminDisease-Free SurvivalDouble-Blind MethodFemaleHumansProgression-Free SurvivalMetforminHormonal therapyMedication adherenceMetformin

Identifiers

PMID37157006
OpenAlexW4375955601

What Socratic 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 Socratic graph.