Which of the following is a risk factor for hyperosmolar hyperglycemic nonketotic syndrome ( HHNS )?

Mr. Garcia, a 68-year-old male with a history of type 2 diabetes, presents to the emergency department with symptoms of extreme thirst, frequent urination and confusion. His blood glucose level is 600 mg / DL. The healthcare provider suspects hyperosmolar hyperglycemic nonketotic syndrome ( HHNS ).