Estimating the influence of body mass index (BMI) on mortality using offspring BMI as an instrumental variable.

ABSTRACT:

Objective

High body mass index (BMI) is an important predictor of mortality but estimating underlying causality is hampered by confounding and pre-existing disease. Here, we use information from the offspring to approximate parental BMIs, with an aim to avoid biased estimation of mortality risk caused by reverse causality.

Methods

The analyses were based on information on 9674 offspring-mother and 9096 offspring-father pairs obtained from the 1958 British birth cohort. Parental BMI-mortality associations were analysed using conventional methods and using offspring BMI as a proxy, or instrument, for their parents' BMI.

Results

In the conventional analysis, associations between parental BMI and all-cause mortality were U-shaped (P_curvature < 0.001), while off

SUBMITTER: Hypponen E 

PROVIDER: S-EPMC7612209 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature