Body Size at Different Ages and Risk of 6 Cancers: A Mendelian Randomization and Prospective Cohort Study.
Daniela MariosaKarl Smith-ByrneTom G RichardsonPietro FerrariMarc J GunterNikos PapadimitriouNeil MurphySofia ChristakoudiKonstantinos K TsilidisElio RiboliDavid C MullerMark P PurdueStephen J ChanockRayjean J HungChristopher Ian AmosTracy A O'MaraPilar AmianoFabrizio PasanisiMiguel Rodríguez BarrancoVittorio KroghAnne TjønnelandJytte HalkjærAurora Perez-CornagoMaría-Dolores ChirlaqueGuri SkeieCharlotta RylanderKristin Benjaminsen BorchDagfinn AuneAlicia K HeathHeather A WardMatthias Bernd SchulzeCatalina BonetElisabete WeiderpassGeorge Davey SmithPaul BrennanMattias J JohanssonPublished in: Journal of the National Cancer Institute (2022)
It is unclear if body weight in early life affects cancer risk independently of adult body weight. To investigate this question for 6 obesity-related cancers, we performed univariable and multivariable analyses using 1) Mendelian randomization (MR) analysis and 2) longitudinal analyses in prospective cohorts. Both the MR and longitudinal analyses indicated that larger early life body size was associated with higher risk of endometrial (odds ratioMR = 1.61, 95% confidence interval = 1.23 to 2.11) and kidney (odds ratioMR = 1.40, 95% confidence interval = 1.09 to 1.80) cancer. These associations were attenuated after accounting for adult body size in both the MR and cohort analyses. Early life body mass index (BMI) was not consistently associated with the other investigated cancers. The lack of clear independent risk associations suggests that early life BMI influences endometrial and kidney cancer risk mainly through pathways that are common with adult BMI.