Monday , October 23 2017
Home / Resources / Articles / What Do We Know about the Dawn Phenomenon?

What Do We Know about the Dawn Phenomenon?

Can basal insulin can make a difference?… 

The dawn phenomenon typically refers to the rise in blood glucose (BG) before and after breakfast in patients with type 1 diabetes. Recently, the dawn phenomenon has been studied in type 2 diabetic patients as well.

In a recent study, Monnier et al. examined data from the past 30 years on the dawn phenomenon to determine the implications for treatment differences, if any, between type 1 and type 2 diabetes patients.

The researchers studied three groups of type 2 diabetic patients (N=248) on either diet only, insulin sensitizers, or secretagogues alone or with insulin sensitizers. The interstitial glucose (IG) concentration was collected overnight by continuous ambulatory IG monitoring for all subjects. The dawn phenomenon produced a mean A1C increase of 0.39% and this increase occurred regardless of treatment type.

The researchers found that the dawn phenomenon occurs frequently among patients with type 2 diabetes, regardless of oral diabetes medication therapy. A goal of type 2 diabetes treatment is the achievement of normoglycemia prior to, and after, breakfast, in order to decrease average daily BG and A1C. It is recommended to achieve this goal in diabetic patients with basal insulin prior to A1C exceeding 7.0%.

Practice Pearls: 
  • The Dawn Phenomenon occurs in both type 1 and type 2 diabetes and refers to the rise in blood glucose (BG) before and after breakfast.
  • Oral diabetic medications are inefficient at controlling the dawn phenomenon and sulfonylureas may induce hypoglycemia in the afternoon or evening. Recommendations include the initiation of basal insulin prior to elevation of A1C above 7.0%.

Porcellati et al., Commentary on Monnier et al. Thirty years of research on the dawn phenomenon: Lessons to optimize blood glucose control in diabetes. Diabetes Care, 2013;36:3860-3862.