A 65-year-old woman, brought into the ED by her family, states that she has been weak, lethargic, and saying “crazy things” over the last 2 days. Her family also states that her medical history is significant only for a disease of her thyroid. Her BP is 120/90 mm Hg, HR is 51 beats per minute, temperature is 94°F rectally, and RR is 12 breaths per minute. On examination, the patient is overweight, her skin is dry, and you notice periorbital nonpitting edema. On neurologic examination, the patient does not respond to stimulation. Which of the following is the most likely diagnosis?
a. Apathetic thyrotoxicosis b. Myxedema coma c. Graves disease d. Acute stroke e. Schizophrenia