Metabolomic profiling identifies complex lipid species associated with response to weight loss interventions
Obesity is an epidemic internationally. While weight loss interventions are efficacious, they are compounded by heterogeneity with regards to clinically relevant metabolic responses. Thus, we sought to identify metabolic pathways and biomarkers that distinguish individuals with obesity who would most benefit from a given type of intervention. Liquid chromatography mass spectrometry-based profiling was used to measure 765 metabolites in baseline plasma from three different weight loss studies: WLM (behavioral intervention, N=443), STRRIDE-PD (exercise trial, N=163), and CBD (surgical cohort, N=125). The primary outcome was percent change in insulin resistance (as measured by the Homeostatic Model Assessment of Insulin Resistance [%{Delta}HOMA-IR]) over the intervention. Overall, 92 individual metabolites were associated with %{Delta}HOMA-IR after adjustment for multiple comparisons. Concordantly, the most significant metabolites were triacylglycerols (TAGs; p=2.3e-5) and diacylglycerols (DAGs; p=1.6e-4), with higher TAG and DAG levels associated with a greater improvement in HOMA-IR. In tests of heterogeneity, 50 metabolites changed differently between weight loss interventions; we found amino acids, peptides, and their analogues to be most significant (4.7e-3) in this category. Our results highlight novel metabolic pathways associated with heterogeneity in response to weight loss interventions, and related biomarkers which could be used in future studies of personalized approaches to weight loss interventions.