Köhler M, et al. – Keeping the objective in mind, researchers demonstrated that type 1 diabetes (T1D) progression risk stratification based on autoantibody titers should focus on time points early after seroconversion. In addition, joint modeling techniques allow for new insights into these associations.

Methods

• Researchers examined data of 613 children from the prospective TEDDY study who were persistent positive for IAA, GADA and/or IA2A autoantibodies.
• They applied a novel approach of Bayesian joint modeling of longitudinal and survival data to assess the potentially time– and covariate–dependent correlation between the longitudinal autoantibody titers and progression time to T1D.

Results

• For all autoantibodies they found a positive correlation between the titers and the T1D progression risk.
• Furthermore, this correlation was estimated as time–constant for IA2A, but decreased over time for IAA and GADA.
• For example the hazard ratio [95% credibility interval] for IAA (per transformed unit) was 3.38 [2.66, 4.38] at 6 months after seroconversion, and 2.02 [1.55, 2.68] at 36 months after seroconversion.