CASE SCENARIO

An 82-year-old patient was diagnosed with diabetes several years ago based on a fasting blood glucose level of 150 mg/dL (8.32 mmol/L) and confirmed by an A1C of 8%. She was otherwise healthy and physically active and, until then, had used diet and exercise to keep her A1C at approximately 8%. When the A1C increased to 9%, you prescribed low-dose metformin, lowering the A1C to 8.5%. But her son worried and took her to an endocrinologist, who convinced both of them that tighter control was necessary to prevent a stroke, severe kidney disease, or death.

The endocrinologist prescribed an intensive regimen of nighttime insulin glargine, sitagliptin (Januvia), and the maximum metformin dose, decreasing the patient's A1C to the endocrinologist's desired goal of 6%. The endocrinologist prescribed a continuous glucose monitor so the patient could track her blood glucose levels constantly. Soon her gait became unsteady, and she developed dizziness, fatigue, and occasional confusion. The endocrinologist referred her to a neurologist, cardiologist, and nephrologist, and more drugs were prescribed. The patient's son was happy with his mother's improved A1C level, but she was not. She asked you, “Why do I feel so terrible?”