Validation and implementation of low-cost dynamic insulin sensitivity tests
Objective: Insulin sensitivity (SI) tests can provide important information for type 2 diabetes risk assessment and investigations of metabolism or pre-diabetes. Our group previously presented the dynamic insulin sensitivity and secretion test (DISST) and the real-time quick DISST (DISTq) as low-cost, low-burden and accurate alternatives to established tests. The DISST provides concurrent SI and endogenous insulin secretion (UN) metrics, the DISTq does not require insulin or C-peptide assays for SI identification, but can return an immediate result.
This study validates the DISST and DISTq in comparison to the euglycemic, hyperinsulinemic clamp (EIC)
Method: Fifty participants (with 10 BMI>30; 10 BMI>25, <30; and 5 BMI<25 of each gender) underwent the EIC and DISST. The DISST protocol requires 5 samples from a 30 minute protocol similar to the IM-IVGTT. Data from the DISST protocol was sufficient to identify SI using both the DISST and DISTq parameter identification methods and UN from the DISST.
Result: DISST and DISTq SI values correlated well to the EIC (R=0.81 and R=0.76, respectively) and each other (R=0.84). UN values obtained during the DISST showed clinically relevant distinctions between participants, and clearly differentiated the beta-cell function of impaired glucose tolerant participants who had the same EIC SI. Participant acceptance of the protocol was high with very minor reported adverse effects.
Conclusion: The DISST and DISTq correlated well against the EIC compared to most established insulin sensitivity tests. The DISST can better differentiate patients as it provides UN metrics that the EIC does not. A computer program makes uptake and use of the model-based DISST and DISTq tests straightforward for clinicians and researchers.