# Simultaneous Evaluation of Shear Wave Elastography and C-Peptide Index for Predicting Need of Insulin Therapy in Type 2 Diabetes: A Pilot Study

## TL;DR

This pilot study explores using shear wave elastography and C-peptide index to predict when people with type 2 diabetes may need insulin therapy.

## Contribution

The study introduces a non-invasive method combining shear wave elastography and C-peptide index to estimate insulin therapy needs in type 2 diabetes.

## Key findings

- Pancreatic shear wave speed was higher in type 2 diabetes patients compared to controls with high sensitivity and specificity.
- Combining shear wave speed and C-peptide index correctly identified non-insulin-treated patients with high accuracy.
- Shear wave dispersion and C-peptide index showed potential for predicting insulin therapy needs with moderate diagnostic accuracy.

## Abstract

Background/Objectives: Recently, shear wave elastography (SWE) and dispersion (SWD) targeting the pancreas have been attempted as noninvasive procedures to evaluate personalized conditions. This study aimed to analyze the feasibility of utilizing them for evaluating the individual need of introducing insulin therapy, combined with the C-peptide index (CPI), in patients with type 2 diabetes mellitus (T2DM). Methods: This study involved 51 patients with T2DM aged ≥20 years old and 20 control subjects without impaired glucose tolerance (CTRL). T2DM were divided into non-insulin-treated (non-INS) and insulin-treated (INS) groups. Their background data, shear wave speed (SWS), and dispersion slope (DS) of the pancreas were obtained on the same day. Results: Pancreatic SWS was higher in T2DM than in CTRL (p < 0.0001), with an AUC of 0.840, sensitivity of 89.1%, and specificity of 70.6%, using a Youden index cutoff of 1.31 m/s. INS and non-INS were discriminated with the cutoff value of 1.70 m/s (p = 0.031, AUC 0.736, sensitivity 55.6% and specificity 89.2%). Pancreatic DS of INS and non-INS was 13.52 and 12.16 (m/s)/kHz, respectively (p = 0.046). Using 12.38 (m/s)/kHz as the cutoff, AUC was 0.718, with sensitivity of 88.9%, specificity of 56.8% and negative predictive value of 95.5%. CPI had AUC of 0.724, sensitivity of 66.7% and specificity of 83.3% with the cutoff of 0.63. With combination of SWS and CPI, all patients with SWS < 1.70 m/s and CPI > 0.476 belonged to non-INS. Conclusions: Simultaneous non-invasive SWE and CPI evaluation showed the feasibility for estimating personalized insulin initiation needs in T2DM, integrating biophysical and hormonal perspectives. Further investigation with a larger, multi-center study population is warranted to enhance the level of evidence.