Untargeted metabolomics data in the By-Band-Sleeve trial and ALSPAC: integrating clinical trial and population cohort...

Metabolomics is the study of measured metabolites and low-molecular weight molecules in a biological specimen, collectively known as the metabolome. Measuring the metabolome in populations is useful for investigating complex, polygenic and multifactorial traits as it can give insight into cellular metabolism and its perturbations in various states of health and disease. Here we present a description of metabolomics data generated using an untargeted mass-spectrometry approach in two studies: (1) the Avon Longitudinal Study of Parents and Children (ALSPAC) - a healthy, general population; and (2) the By-Band-Sleeve trial (BBS) - a pragmatic randomised controlled trial (RCT) of metabolic and bariatric surgery (MBS) plus a non-randomised observational sub-study.

Samples for this work were collected from ALSPAC participants at 30 years of age. Two sample collection efforts were made within BBS - firstly, from the RCT comparing the effectiveness of three types of MBS: the Roux-en-Y gastric bypass ("bypass"), laparoscopic adjustable gastric band ("band") and the sleeve gastrectomy ("sleeve"), and secondly from the non-randomised (observational) study of MBS. In both instances, samples were collected from patients before and after surgery. In total, 2128 samples were sent for mass-spectrometry (MS) metabolomics analysis by Metabolon (Discovery HD4 platform). Data underwent quality control (QC) via a standard pipeline using the R package metaboprep.

After QC, the combined dataset consists of semi-quantitative data for 1176 features in 517 ALSPAC participants and 1062 BBS participants (1018 from the RCT and 44 from the non-randomised study) (1013 pre-surgery samples and 421 post-surgery samples).

Overall, we have provided a summary of MS data produced across two different study populations, described the QC procedures undertaken and provided some data validation analyses. Bringing together samples from these two studies in a single experiment offers a novel study design able to explore the biological implications of weight and intentional weight loss.