Evidence map›Metformin × adverse events & safety›PMID 30896668›Full record

SynthesisMedicine2019

Metformin use and prostate cancer risk: A meta-analysis of cohort studies.

Zhaohan Feng, Xiaofeng Zhou, Naibo Liu, Jianfeng Wang, Xing Chen, Xin Xu

Abstract readMeta-AnalysisSystematic Review
PubMed Full text at PMC Publisher
In one paragraph

Synthesis in Medicine, 2019. The graph read 1 number from its abstract, feeding 1 cell of the map, but none could be read as for or against, so it casts no vote. Cited by 19 papers, 2 of them syntheses that pooled it.

1number the graph read from it
0cells of the map it votes in
19citing papers in PubMed, 2 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.

Read, but not usablea number the graph found but could not read as for or against

Adverse events & safetyan association or prognostic statement, not a treatment comparison · t2dfeeds one cell of the map
RR 0.970.80 to 1.16P = .711
In a random-effect pooled analysis, metformin use was not significantly associated with the risk of prostate cancer (RR 0.97, 95% CI 0.80-1.16, P = .711).
FeedsMetformin×adverse events & safety

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.

Metformin×adverse events & safety

No readable resultOpen on the map →What to test next →

22 readable studies in this cell: 9 favour the treatment, 8 find no difference, 5 favour the comparator.

Belief with this paper
0.27contested · 4 families support, 11 contradict · against placebo
Without itNot a counted family in this claim, so removing it changes nothing.
← favours the treatmentfavours the comparator →
0 · no effect
NCT017190031,413 enrolled · 2012
Adjusted mean -0.72-0.95 to -0.48
NCT018093271,186 enrolled · 2013
Δ -0.40-0.59 to -0.21
NCT022730501,136 enrolled · 2014
Δ -8.90-13.3 to -4.50
NCT01126580807 enrolled · 2010
Δ -0.22-0.36 to -0.08
NCT01023581784 enrolled · 2009
Δ -0.67-0.96 to -0.37
NCT00386100688 enrolled · 2006
Δ 1.47-14.8 to 20.8
NCT01217073685 enrolled · 2010
Δ 1.00-9.80 to 13.1
NCT01890122647 enrolled · 2013
Δ -0.68-0.89 to -0.47
NCT00727857600 enrolled · 2007
Δ 0.860.51 to 1.22
NCT01958671461 enrolled · 2013
Δ -2.60-13.1 to 8.10
NCT00328172302 enrolled · 2006
Δ -0.85-1.10 to -0.59
NCT01485614200 enrolled · 2012
Δ 2.40-10.0 to 14.9

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.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

5 · Its place in the literature

Who cites it

19 citing papers in PubMed, 2 syntheses or guidelines pooled it.

  1. Pooled it
  2. Pooled it
  3. Trial
  4. Review
  5. Article
  6. Review
  7. Review
  8. Article
  9. Article
  10. Article
  11. Article
  12. Review
  13. Review
  14. Article
  15. Review
  16. Article
  17. Review
  18. Cancer Progress and Priorities: Prostate Cancer.Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology · 2020
    Article
  19. Article
6 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

7 · Who and what money

Authors and funding

6 authors.

Zhaohan FengDepartment of Urology, China-Japan Friendship Hospital, Beijing, China.
Xiaofeng Zhou
Naibo Liu
Jianfeng Wang
Xing Chen
Xin Xu

Funding

No grant is acknowledged in the PubMed record.

8 · The paper itself

Abstract

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

backgroundThe relationship between metformin use and the risk of prostate cancer is still inconclusive. Therefore, we performed a systematic review and meta-analysis of all eligible cohort studies to evaluate a potential association of metformin use with prostate cancer risk.

methodsA comprehensive literature search was performed in PubMed and Web of Science databases through July 2018. A DerSimonian and Laird random-effects model was applied to calculate the pooled relative risk (RR) and its 95% confidence interval (CI).

resultsEighteen cohort or nested case-control studies were included in this study with a total of 52,328 cases. In a random-effect pooled analysis, metformin use was not significantly associated with the risk of prostate cancer (RR 0.97, 95% CI 0.80-1.16, P = .711). Statistically significant heterogeneity was identified among included studies (P < .001, I = 98.1%). Sensitivity analysis indicated that no single study dominated the pooled RR.

conclusionThe present large meta-analysis of cohort studies did not find an association between metformin use and prostate cancer risk.

Indexed as

Case-Control StudiesCohort StudiesDiabetes Mellitus, Type 2HumansHypoglycemic AgentsMaleMetforminProstatic NeoplasmsRisk FactorsHypoglycemic AgentsMetformin

Identifiers

PMID30896668
PMCPMC6709307

What Socratic holds

Texttitle and abstract
LicenceCC BY-NC-ND
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.