Trial reportCirculation2022

Effects of Long-term Metformin and Lifestyle Interventions on Cardiovascular Events in the Diabetes Prevention Program and Its Outcome Study.

Ronald B Goldberg, Trevor J Orchard, Jill P Crandall, Edward J Boyko, Matthew Budoff, Dana Dabelea, Kishore M Gadde, William C Knowler, Christine G Lee, David M Nathan and 3 more

2 registry-linked trialsAbstract readRandomized Controlled Trial
In one paragraph

Trial report in Circulation, 2022. The graph read 1 number from its abstract, feeding 2 cells of the map, but it casts no vote: the report of the main result of NCT00004992 is not on the map. It reports registered trial NCT00004992. Cited by 84 papers, 1 of them a synthesis that pooled it.

1number the graph read from it
0cells of the map it votes in
84citing papers in PubMed, 1 pooled it
–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.

← favours the treatmentfavours the comparator →
1 · no effect
Cardiovascular eventsno clear difference · against placebo · t2d, ascvdfeeds 2 cells of the map
HR 1.030.78 to 1.37
RESULTS: Neither metformin nor lifestyle intervention reduced the primary outcome: metformin versus placebo hazard ratio 1.03 (95% CI, 0.78-1.37; CONCLUSIONS: Neither metformin nor lifestyle reduced major cardiovascular events in DPPOS over 21 years despite long-term prevention of diabetes.

clause the extractor read what became the number

2 · Its place on the map

Where it lands on the map

Rows are treatments, columns are outcomes. The coloured squares are the cells this paper feeds, coloured by the vote it casts there. Click one to jump to what this paper adds to it.

supports the treatmentfavours the comparatorno clear differenceread, but no usable result
3 · What it changes

What it adds to each cell

For every cell the paper feeds: the belief in the claim with and without this paper, and this paper's estimate drawn against every other readable study in the cell. The ringed dot is this paper.

Diet, exercise & lifestyle×cardiovascular events

Does not voteOpen on the map →What to test next →

2 readable studies in this cell: 2 favour the treatment, 0 find no difference, 0 favour the comparator.

Belief with this paper
0.50one trial · 1 family supports, 0 contradict · against placebo
Without itNot a counted family in this claim, so removing it changes nothing.
← favours the treatmentfavours the comparator →
1 · no effect

This paper's own estimate is on a different scale from the rest of the cell, so it is not drawn here.

Metformin×cardiovascular events

Does not voteOpen on the map →What to test next →

5 readable studies in this cell: 4 favour the treatment, 1 find no difference, 0 favour the comparator.

Belief with this paper
0.50contested · 4 families support, 2 contradict · against placebo
Without itNot a counted family in this claim, so removing it changes nothing.
← favours the treatmentfavours the comparator →
1 · no effect

This paper's own estimate is on a different scale from the rest of the cell, so it is not drawn here.

4 · 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.

NCT00004992 phase3completed

Diabetes Prevention Program

Ran1996Enrolled3,234Registered outcomes1Posted comparisons0ConditionsDiabetes Mellitus, Non-Insulin-Dependent, Glucose IntoleranceArmsIntensive lifestyle, Metformin, Placebo
PMID 11832527PMID 16855264other papers from this trial
Open the trial in the graph
NCT00038727 phase3completed

Diabetes Prevention Program Outcomes Study

Ran1996Enrolled2,779Registered outcomes17Posted comparisons2ConditionsCancer, CVD, Diabetes MellitusArmsDPPOS Boost Lifestyle, DPPOS Group Lifestyle, Intensive Lifestyle Group Session, Metformin
PMID 19878986PMID 26377054PMID 11832527other papers from this trial
Open the trial in the graph
5 · Its place in the literature

Who cites it

84 citing papers in PubMed, 1 synthesis or guideline pooled it.

  1. Pooled it
  2. Trial
  3. Trial
  4. Trial
  5. Trial
  6. Trial
  7. Trial
  8. Article
  9. Review
  10. Nutrition and Culinary Education in Food Is Medicine Interventions: A Scoping Review.Journal of the Academy of Nutrition and Dietetics · 2026
    Article
  11. Review
  12. Article
  13. Article
  14. Article
  15. Metformin Beyond Glycemic Control: Cardiovascular Protection and Diabetes Prevention.Journal of cardiovascular development and disease · 2026
    Review
  16. Review
  17. Review
  18. Article
  19. Review
  20. Review

24 more citing papers are in PubMed but not listed here.

6 · The record

Corrections and comments

7 · Who and what money

Authors and funding

13 authors.

Ronald B GoldbergUniversity of Miami Miller School of Medicine, FL (R.B.G.).ORCID 0000-0003-0924-1110
Trevor J OrchardUniversity of Pittsburgh Graduate School of Public Health, PA (T.J.O.).
Jill P CrandallAlbert Einstein College of Medicine, Bronx, NY (J.P.C.).
Edward J BoykoVA Puget Sound Health Care System, Seattle, WA (E.J.B.).ORCID 0000-0002-3695-192X
Matthew BudoffLos Angeles Biomedical Research Institute, Torrance, CA (M.B.).ORCID 0000-0002-9616-1946
Dana DabeleaUniversity of Colorado Anschutz Medical Campus, Aurora (D.D.).
Kishore M GaddePennington Biomedical Research Center, Baton Rouge, LA (K.M.G.).ORCID 0000-0002-1856-5574
William C KnowlerNational Institute of Diabetes and Digestive and Kidney Diseases, Phoenix, AZ (W.C.K.).ORCID 0000-0002-7004-5197
Christine G LeeNational Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD (C.G.L.).ORCID 0000-0001-5637-8924
David M NathanMassachusetts General Hospital, Harvard Medical School, Boston (D.M.N.).
Karol WatsonDavid Geffen School of Medicine at UCLA, Los Angeles, CA (K.W.).ORCID 0000-0003-3658-6165
Marinella TemprosaBiostatistics Center and Milken Institute School of Public Health, George Washington University, Rockville, MD (M.T.).ORCID 0000-0002-9976-745X
Diabetes Prevention Program Research Group*

Funding

PRIMARY PREVENTION TRIAL--DATA COORDINATING CENTERU01DK048489 · NIDDK · GEORGE WASHINGTON UNIVERSITY · PI JABLONSKI, KATHLEEN ANN, TEMPROSA, MARINELLA · 1994 to 2021
$84.8M
Translational Research CoreP30DK020541 · NIDDK · ALBERT EINSTEIN COLLEGE OF MEDICINE, INC · PI Shuibing Chen · 2015 to 2026
$27.7M
Post-DDP Follow-up StudyU01DK048413 · NIDDK · UNIVERSITY OF WASHINGTON · PI KAHN, STEVEN EMANUEL · 1994 to 2021
$13.7M
PRIMARY PREVENTION TRIAL (DPT-2)U01DK048397 · NIDDK · MASSACHUSETTS GENERAL HOSPITAL · PI NATHAN, DAVID M · 1994 to 2021
$12.0M
NIDDM PRIMARY PREVENTION TRIAL (DPT 2)U01DK048404 · NIDDK · ST. LUKE'S-ROOSEVELT INST FOR HLTH SCIS · PI LAFERRERE, BLANDINE B · 1994 to 2021
$11.6M
PRIMARY PREVENTION TRIAL (DPT-2)U01DK048339 · NIDDK · UNIVERSITY OF CALIFORNIA, SAN DIEGO · PI ARANETA, MARIA ROSARIO GORREZ, MUDALIAR, SUNDER · 1994 to 2022
$11.4M
NIDDM PRIMARY PREVENTION TRIALU01DK048412 · NIDDK · UNIVERSITY OF PITTSBURGH AT PITTSBURGH · PI VENDITTI, ELIZABETH MARY · 1994 to 2021
$11.4M
PRIMARY PREVENTION TRIALU01DK048387 · NIDDK · MEDSTAR RESEARCH INSTITUTE · PI MAGEE, MICHELLE FISCHMANN · 1994 to 2022
$11.1M
TITLE OMITTEDU01DK048349 · NIDDK · YESHIVA UNIVERSITY · PI CRANDALL, JILL P · 1994 to 2021
$11.0M
PRIMARY PREVENTION TRIALU01DK048443 · NIDDK · UNIVERSITY OF SOUTHERN CALIFORNIA · PI WATSON, KAROL E · 1994 to 2021
$10.2M
Post-DPP Follow-up StudyU01DK048375 · NIDDK · UNIVERSITY OF COLORADO DENVER · PI DABELEA, DANA · 1994 to 2022
$10.0M
Post-Diabetes Prevention Program (DPP)U01DK048381 · NIDDK · UNIVERSITY OF CHICAGO · PI EHRMANN, DAVID A · 1994 to 2021
$9.6M
NCRR NIH HHS M01 RR016587NIDDK NIH HHS P30 DK020541NIDDK NIH HHS P30 DK111022NIDDK NIH HHS U01 DK048339NIDDK NIH HHS U01 DK048349NIDDK NIH HHS U01 DK048375NIDDK NIH HHS U01 DK048377NIDDK NIH HHS U01 DK048380NIDDK NIH HHS U01 DK048381NIDDK NIH HHS U01 DK048387NIDDK NIH HHS U01 DK048397NIDDK NIH HHS U01 DK048400NIDDK NIH HHS U01 DK048404NIDDK NIH HHS U01 DK048406NIDDK NIH HHS U01 DK048407NIDDK NIH HHS U01 DK048411NIDDK NIH HHS U01 DK048412NIDDK NIH HHS U01 DK048413NIDDK NIH HHS U01 DK048434NIDDK NIH HHS U01 DK048437NIDDK NIH HHS U01 DK048443NIDDK NIH HHS U01 DK048468NIDDK NIH HHS U01 DK048485NIDDK NIH HHS U01 DK048489NIDDK NIH HHS U01 DK048514
8 · The paper itself

Abstract

The marked sentences are the ones the graph read a number from.

backgroundLifestyle intervention and metformin have been shown to prevent diabetes; however, their efficacy in preventing cardiovascular disease associated with the development of diabetes is unclear. We examined whether these interventions reduced the incidence of major cardiovascular events over a 21-year median follow-up of participants in the DPP trial (Diabetes Prevention Program) and DPPOS (Diabetes Prevention Program Outcomes Study).

methodsDuring DPP, 3234 participants with impaired glucose tolerance were randomly assigned to metformin 850 mg twice daily, intensive lifestyle or placebo, and followed for 3 years. During the next 18-year average follow-up in DPPOS, all participants were offered a less intensive group lifestyle intervention, and unmasked metformin was continued in the metformin group. The primary outcome was the first occurrence of nonfatal myocardial infarction, stroke, or cardiovascular death adjudicated by standard criteria. An extended cardiovascular outcome included the primary outcome or hospitalization for heart failure or unstable angina, coronary or peripheral revascularization, coronary heart disease diagnosed by angiography, or silent myocardial infarction by ECG. ECGs and cardiovascular risk factors were measured annually.

resultsNeither metformin nor lifestyle intervention reduced the primary outcome: metformin versus placebo hazard ratio 1.03 (95% CI, 0.78-1.37;

conclusionsNeither metformin nor lifestyle reduced major cardiovascular events in DPPOS over 21 years despite long-term prevention of diabetes. Provision of group lifestyle intervention to all, extensive out-of-study use of statin and antihypertensive agents, and reduction in the use of study metformin together with out-of-study metformin use over time may have diluted the effects of the interventions. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifiers: DPP (NCT00004992) and DPPOS (NCT00038727).

Indexed as

Diabetes Mellitus, Type 2MetforminMyocardial InfarctionHumansHypoglycemic AgentsLife StyleOutcome Assessment, Health CareHypoglycemic AgentsMetformincardiovascular diseasesdiabetes mellitus, type 2metformin

Identifiers

PMID35603600
PMCPMC9179081

What OpenQuestion holds

Texttitle and abstract
LicenceTDM
Read underepoch 390

Registered trials

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.