Evidence map›Paper›PMID 34021349›Full record

ArticleJournal of the National Cancer Institute2022

The Role of Mendelian Randomization Studies in Deciphering the Effect of Obesity on Cancer.

Zhe Fang, Mingyang Song, Dong Hoon Lee, Edward L Giovannucci

Open access · greenAbstract read
PubMed Full text at PMC Publisher
In one paragraph

Article in Journal of the National Cancer Institute, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 31 papers, 3 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
31citing papers in PubMed, 3 pooled it
3.3field-weighted citation impact, top 5% 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

31 citing papers in PubMed, 3 syntheses or guidelines pooled it, 48 citations in OpenAlex.

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4 · The record

Corrections and comments

5 · Who and what money

Authors and funding

4 authors at 2 institutions in 1 country.

Zhe FangDepartment of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.ORCID 0000-0003-0864-3644
Mingyang SongDepartment of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.ORCID 0000-0002-1324-0316
Dong Hoon LeeDepartment of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA.ORCID 0000-0003-1329-4637
Edward L GiovannucciDepartment of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.ORCID 0000-0002-6123-0219
Harvard University · USBrigham and Women's Hospital · US

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Associations of obesity have been established for at least 11 cancer sites in observational studies, though some questions remain as to causality, strength of associations, and timing of associations throughout the life course. In recent years, Mendelian randomization (MR) has provided complementary information to traditional approaches, but the validity requires that the genetic instrumental variables be causally related to cancers only mediated by the exposure. We summarize and evaluate existing evidence from MR studies in comparison with conventional observational studies to provide insights into the complex relationship between obesity and multiple cancers. MR studies further establish the causality of adult obesity with esophageal adenocarcinoma and cancers of the colorectum, endometrium, ovary, kidney, and pancreas, as well as the inverse association of early life obesity with breast cancer. MR studies, which might account for lifelong adiposity, suggest that the associations in observational studies typically based on single measurement may underestimate the magnitude of the association. For lung cancer, MR studies find a positive association with obesity, supporting that the inverse association observed in some conventional observational studies likely reflects reverse causality (loss of lean body mass before diagnosis) and confounding by smoking. However, MR studies have not had sufficient power for gallbladder cancer, gastric cardia cancer, and multiple myeloma. In addition, more MR studies are needed to explore the effect of obesity at different timepoints on postmenopausal breast cancer and aggressive prostate cancer.

Indexed as

Breast NeoplasmsMendelian Randomization AnalysisAdiposityAdultBody Mass IndexCausalityFemaleGenome-Wide Association StudyHumansMaleObesityPolymorphism, Single NucleotideRisk Factors

Identifiers

PMID34021349
PMCPMC8902442
OpenAlexW3160932552

What OpenQuestion 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 OpenQuestion graph.