Do Patients on Glucagon-Like Peptide-1 (GLP-1) Receptor Agonists Require Longer Fasting Prior to Vibration Controlled Transient Elastography?

Vibration-controlled transient elastography (VCTE) requires a three-hour fasting period to minimize postprandial increases in liver stiffness measurement (LSM), but this recommendation predates widespread use of glucagon-like peptide-1 receptor agonists (GLP-1-RAs), which alter gastric emptying and postprandial hemodynamics. We evaluated whether current fasting guidance remains valid in 23 participants, including 12 with cirrhosis, receiving GLP-1 RAs who underwent serial LSM following standardized meal ingestion. LSM increased 20.6% at 30-60 minutes but fell back to <10% by 3 hours. Most patients returned to baseline by 3-4 hours, supporting adequacy of a three-hour fast, however, some patients required 4 hours for full return to baseline.