uk-dgm MCQ (SBA): Recurrent Hypoglycaemia Mimicking Delirium in Dementia

A 82-year-old woman with vascular dementia and diabetes presents with recurrent episodes of acute confusion. Each episode lasts 2-3 hours and resolves spontaneously. They occur at irregular intervals. Her blood glucose during an episode is 2.6 mmol/L. Between episodes, her glucose is 5-8 mmol/L. She takes Gliclazide 80 mg BD. What is the MOST likely cause of her recurrent confusion?