Evidence map›Paper›PMID 33656637›Full record

Observational studyBreast cancer research and treatment2021

The impact of body mass index on breast cancer incidence among women at increased risk: an observational study from the International Breast Intervention Studies.

Samuel G Smith, Ivana Sestak, Michelle A Morris, Michelle Harvie, Anthony Howell, John Forbes, Jack Cuzick

Open access · hybridAbstract readObservational Study
PubMed Full text at PMC Publisher
In one paragraph

Observational study in Breast cancer research and treatment, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 12 papers, 2 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
12citing papers in PubMed, 2 pooled it
1.5field-weighted citation impact, top 15% 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

12 citing papers in PubMed, 2 syntheses or guidelines pooled it, 24 citations in OpenAlex.

  1. Pooled it
  2. Pooled it
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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

7 authors at 5 institutions in 2 countries.

Samuel G Smith *Leeds Institute of Health Science, University of Leeds, Clarendon Way, Leeds, LS2 9NL, UK. s.smith1@leeds.ac.uk.ORCID http://orcid.org/0000-0003-1983-4470
Ivana Sestak *Centre for Cancer Prevention, Wolfson Institute of Preventive Medicine, Queen Mary University of London, London, UK.
Michelle A MorrisLeeds Institute for Data Analytics, School of Medicine, University of Leeds, Leeds, UK.
Michelle HarviePrevent Breast Cancer Unit, Nightingale Breast Screening Centre, Manchester University NHS Foundation Trust, Manchester, UK.
Anthony HowellPrevent Breast Cancer Unit, Nightingale Breast Screening Centre, Manchester University NHS Foundation Trust, Manchester, UK.
John ForbesBreast Cancer Trials, Newcastle, Australia.
Jack CuzickCentre for Cancer Prevention, Wolfson Institute of Preventive Medicine, Queen Mary University of London, London, UK.
Queen Mary University of London · GBUniversity of Leeds · GBBreast Cancer Trials · AUManchester University NHS Foundation Trust · GBUniversity of Manchester · GB

Funding

Cancer Research UK 5032Cancer Research UK C569/A16891Cancer Research UK C569/A5032Cancer Research UK C8162/A26893
6 · The paper itself

Abstract

backgroundWe investigated the association between body mass index (BMI) and breast cancer risk in women at increased risk of breast cancer receiving tamoxifen or anastrozole compared with placebo using data from the International Breast Cancer Intervention Studies [IBIS-I (tamoxifen) and IBIS-II (anastrozole)].

methodsBaseline BMI was calculated from nurse assessed height and weight measurements for premenopausal (n = 3138) and postmenopausal (n = 3731) women in IBIS-I and postmenopausal women in IBIS-II (n = 3787). The primary endpoint was any breast cancer event (invasive and ductal carcinoma in situ). We used Cox proportional hazards regression to calculate hazard ratios (HRs) for risk after adjustment for covariates.

resultsThere were 582 (IBIS-I) and 248 (IBIS-II) breast cancer events [median follow-up = 16.2 years (IQR 14.4-17.7) and 10.9 years (IQR 8.8-13.0), respectively]. In adjusted analysis, women with a higher BMI had an increased breast cancer risk in both IBIS-I [HR = 1.06 per 5 kg/m

conclusionsHigher BMI is associated with greater breast cancer risk in postmenopausal women at increased risk of the disease, but no effect was observed in premenopausal women. The lack of interaction between BMI and treatment group on breast cancer risk suggests women are likely to experience benefit from preventive therapy regardless of their BMI. Trial registration Both trials were registered [IBIS-I: ISRCTN91879928 on 24/02/2006, retrospectively registered ( http://www.isrctn.com/ISRCTN91879928 ); IBIS-II: ISRCTN31488319 on 07/01/2005, retrospectively registered ( http://www.isrctn.com/ISRCTN31488319 )].

Indexed as

Breast NeoplasmsCarcinoma, Intraductal, NoninfiltratingAnastrozoleBody Mass IndexFemaleHumansIncidenceRisk FactorsTamoxifenAnastrozoleTamoxifenAnastrozoleBody mass indexBreast cancerChemopreventionTamoxifenWeight

Identifiers

PMID33656637
PMCPMC8233270
OpenAlexW3134279900

What Socratic holds

Textmetadata
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.