Fast Five Quiz: Type 2 Diabetes Mellitus Presentation and Diagnosis

Romesh Khardori, MD, PhD


January 30, 2020

The dawn phenomenon refers to the abnormal early morning (usually between 2 AM and 8 AM) increase in blood glucose level (> 20 mg/dL) that affects > 50% of patients with type 2 DM. Patients with type 2 DM who experience the dawn phenomenon have both higher A1c  and 24-hour glucose levels compared with patients without type 2 DM.

The Somogyi effect (also called Somogyi phenomenon or rebound hyperglycemia) refers to hypoglycemia that occurs during the nighttime hours as a result of excess exogenous insulin (eg, from inadvertent or ill-timed insulin administration or missed meals). The Somogyi effect, which is more common in patients with type 1 DM than in patients with type 2 DM, remains highly controversial in clinical practice based on studies refuting nocturnal hypoglycemia as a cause of morning or daytime hyperglycemia.

Macrovascular complications associated with type 2 DM include cardiovascular disease, cerebrovascular accident, and peripheral vascular disease. Microvascular complications such as retinal, renal, and neuropathic disease also are associated with type 2 DM. Randomized trials have shown that good glycemic control can delay or prevent onset of these complications.

Learn more about the effects of the dawn phenomenon in patients with type 2 DM.


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