Lipidomic predictors of residual insulin production in adults with newly diagnosed type 1 diabetes

INTRODUCTION: Alterations in the lipidomic profile have been implicated in the development and disease progression in type 1 diabetes. We have previously demonstrated that the lipidomic profile at the time of diagnosis could predict residual insulin production the following 6 to 12 months, in children. OBJECTIVES: Given the strong influence of age on residual insulin production, we aimed to investigate the association between the lipidomic profile and residual insulin production in adults newly diagnosed with type 1 diabetes. METHOD: We performed lipidomic profiling of plasma samples from 29 adults newly diagnosed with type 1 diabetes. Linear regression and backward stepwise multiple regression analyses were used to assess the association between the lipidomic profile and C-peptide levels during a 2 h mixed-meal tolerance test. All data was derived from an original randomised clinical trial with the trial registration number: EudraCT number: 2019-004434-41. RESULTS: The lysophosphatidylcholines (LPCs) were the strongest predictors of residual insulin production. Higher baseline LPC levels were associated with increased residual insulin production at week 52. Specifically, LPC(20:4/0:0), LPC(0:0/20:4), and LPC(0:0/16:0) were significantly associated with improved residual insulin production. Additionally, reduced levels of sphingolipids, including sulfatides, were negatively associated with residual insulin production. CONCLUSION: In adults, the LPC class, in particular, showed potential as a biomarker for preserved residual insulin production. This contrasts previous observations in children and highlights the importance of age-stratified research to understand the role of the lipidome in type 1 diabetes.