Observational studyBMC nephrology2017

Risk of acute kidney injury and survival in patients treated with Metformin: an observational cohort study.

Samira Bell, Bassam Farran, Stuart McGurnaghan, Rory J McCrimmon, Graham P Leese, John R Petrie, Paul McKeigue, Naveed Sattar, Sarah Wild, John McKnight and 3 more

Open access · goldFull text readObservational Study
In one paragraph

Observational study in BMC nephrology, 2017. The graph read 2 numbers from its abstract, feeding 2 cells of the map, but none could be read as for or against, so it casts no vote. It also reports an association that does not count as treatment evidence, such as HR 0.81 (0.69 to 0.94) for survival at 28 days. Cited by 36 papers.

2numbers the graph read from it
0cells of the map it votes in
36citing papers in PubMed
6.0field-weighted citation impact, top 3% 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.

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

AKI incidencecurrent metformin use vs unexposed periodsan association or prognostic statement, not a treatment comparison · ckd, t2dfeeds one cell of the map
HR 0.940.87 to 1.02p = 0.15
After adjustment for age, sex, diabetes duration, calendar time, number of diabetes drugs and baseline renal function, current metformin use was not associated with AKI incidence, HR 0.94 (95% CI 0.87, 1.02, p = 0.15).
Survival at 28 daysbeing on metformin at admission vs not exposed to metformin, in those with incident AKIan association or prognostic statement, not a treatment comparison · ckd, t2dfeeds one cell of the map
HR 0.810.69 to 0.94p = 0.006
Among those with incident AKI, being on metformin at admission was associated with a higher rate of survival at 28 days (HR 0.81, 95% CI 0.69, 0.94, p = 0.006) even after adjustment for age, sex, pre-admission eGFR, HbA CONCLUSIONS: Contrary to common perceptions, we found no evidence that metformin increases incidence of AKI and was associated with higher 28 day survival following incident AKI.

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×kidney outcomes

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

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

Belief with this paper
0.25no deciding trial · 0 families support, 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×all-cause mortality

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

1 readable study in this cell: 0 favour the treatment, 1 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
NCT000387272,779 enrolled · 1996
HR 0.990.79 to 1.25

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

36 citing papers in PubMed, 85 citations in OpenAlex.

  1. Trial
  2. Trial
  3. Review
  4. Article
  5. Article
  6. Review
  7. Article
  8. Article
  9. Review
  10. Article
  11. Management of diabesity: Current concepts.World journal of diabetes · 2023
    Review
  12. Acute kidney injury in diabetes mellitus: Epidemiology, diagnostic, and therapeutic concepts.FASEB journal : official publication of the Federation of American Societies for Experimental Biology · 2023
    Review
  13. Article
  14. Article
  15. Article
  16. Review
  17. Review
  18. Article
  19. Review
  20. Review
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

13 authors at 6 institutions in 1 country.

Samira BellRenal Unit, Ninewells Hospital, Dundee, DD1 9SY, UK. samira.bell@nhs.net.ORCID http://orcid.org/0000-0001-9100-1575
Bassam FarranInstitute of Genetics and Molecular Medicine University of Edinburgh, Edinburgh, UK.
Stuart McGurnaghanInstitute of Genetics and Molecular Medicine University of Edinburgh, Edinburgh, UK.
Rory J McCrimmonDivision of Molecular & Clinical Medicine, School of Medicine, University of Dundee, Dundee, UK.
Graham P LeeseDepartment of Medicine, University of Dundee, Dundee, UK.
John R PetrieInstitute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, UK.
Paul McKeigueCentre for Population Health Sciences, University of Edinburgh Medical School, Edinburgh, UK.
Naveed SattarInstitute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, UK.
Sarah WildCentre for Population Health Sciences, University of Edinburgh Medical School, Edinburgh, UK.
John McKnightDepartment of Medicine, Western General Hospital, Edinburgh, UK.
Robert LindsayInstitute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, UK.
Helen M ColhounInstitute of Genetics and Molecular Medicine University of Edinburgh, Edinburgh, UK.
Helen LookerDivision of Population Health Sciences, School of Medicine, University of Dundee, Dundee, UK.
Institute of Genetics and Cancer · GBUniversity of Dundee · GBUniversity of Glasgow · GBUniversity of Edinburgh · GBNinewells Hospital · GBWestern General Hospital · GB

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.

backgroundWhether metformin precipitates lactic acidosis in patients with chronic kidney disease (CKD) remains under debate. We examined whether metformin use was associated with an increased risk of acute kidney injury (AKI) as a proxy for lactic acidosis and whether survival among those with AKI varied by metformin exposure.

methodsAll individuals with type 2 diabetes and available prescribing data between 2004 and 2013 in Tayside, Scotland were included. The electronic health record for diabetes which includes issued prescriptions was linked to laboratory biochemistry, hospital admission, death register and Scottish Renal Registry data. AKI events were defined using the Kidney Disease Improving Global Outcomes criteria with a rise in serum creatinine of at least  26.5 μmol/l or a rise of greater than 150% from baseline for all hospital admissions. Cox Regression Analyses were used to examine whether person-time periods in which current metformin exposure occurred were associated with an increased rate of first AKI compared to unexposed periods. Cox regression was also used to compare 28 day survival rates following first AKI events in those exposed to metformin versus those not exposed.

resultsTwenty-five thousand one-hundred fourty-eight patients were included with a total person-time of 126,904 person years. 4944 (19.7%) people had at least one episode of AKI during the study period. There were 32.4 cases of first AKI/1000pyrs in current metformin exposed person-time periods compared to 44.9 cases/1000pyrs in unexposed periods. After adjustment for age, sex, diabetes duration, calendar time, number of diabetes drugs and baseline renal function, current metformin use was not associated with AKI incidence, HR 0.94 (95% CI 0.87, 1.02, p = 0.15). Among those with incident AKI, being on metformin at admission was associated with a higher rate of survival at 28 days (HR 0.81, 95% CI 0.69, 0.94, p = 0.006) even after adjustment for age, sex, pre-admission eGFR, HbA

conclusionsContrary to common perceptions, we found no evidence that metformin increases incidence of AKI and was associated with higher 28 day survival following incident AKI.

Indexed as

Acidosis, LacticAcute Kidney InjuryAgedAge DistributionCohort StudiesComorbidityDiabetes Mellitus, Type 2Drug-Related Side Effects and Adverse ReactionsFemaleHumansIncidenceMaleMetforminMiddle AgedRisk FactorsScotlandMetforminAcute kidney injuryDiabetesEpidemiologyMetforminSurvival

Identifiers

PMID28526011
PMCPMC5437411
OpenAlexW2616446856

What Socratic holds

Textfull text, public
LicenceCC BY
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.