A 67-year-old woman has diabetes and mild hypertension. She has diabetic retinopathy and states that she cannot feel her legs. In addition, she has recurrent episodes of light-headedness when she gets up in the morning. She reported that she had fainted this morning.

What is the most likely cause of her syncope? (Answer is posted in the comment section below!) *This patient case is from the Editorial Team of Docplexus and is meant for educational purposes only.