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

<ns3:p> 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. The Avon Longitudinal Study of Parents and Children (ALSPAC) is a birth cohort that enrolled pregnant women in 1991/92 and has followed them up ever since. Samples for this work were collected from ALSPAC participants at 30 years of age. By-Band-Sleeve (BBS) is a pragmatic randomised controlled trial (RCT) which evaluated the clinical effectiveness of three different types of bariatric surgery. Two sample collection efforts were made within BBS – firstly, from the RCT comparing the effectiveness of three types of bariatric surgery: the Roux-en-Y gastric bypass (“bypass”), laparoscopic adjustable gastric band (“band”) and the sleeve gastrectomy (“sleeve”), and secondly from a non-randomised (observational) study of bariatric surgery. In both instances, samples were collected from patients before and after surgery. Samples were sent for mass-spectrometry (MS) metabolomics analysis by Metabolon (Discovery HD4 platform). Bringing together samples from these two studies in a single experiment offers a novel study design able to explore the biological implications of – in this case – weight and intentional weight loss. Data underwent quality control (QC) via a standard pipeline using the R package <ns3:italic>metaboprep</ns3:italic> . Post-filtering, the dataset consists of semi-quantitative data for 1253 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. </ns3:p>