From the Guidelines
The Dawn Phenomenon is a natural increase in blood glucose levels that occurs in the early morning hours, typically between 2 and 8 am.
Characteristics of the Dawn Phenomenon
- It is caused by the release of certain hormones, such as cortisol and growth hormone, that raise blood glucose levels
- It can be more pronounced in people with diabetes, particularly those with type 2 diabetes
- It can be challenging to control, especially for individuals using Multiple Daily Injections (MDI) with Long-Acting Analogs (LAAs), as these may not provide sufficient coverage for the Dawn Phenomenon 1
Management of the Dawn Phenomenon
- Adjusting basal insulin doses or using insulin pumps can help mitigate the effects of the Dawn Phenomenon
- Correction insulin doses may need to be adjusted based on the individual's glucose levels and insulin sensitivity
- Monitoring blood glucose levels regularly, especially during the early morning hours, is crucial to managing the Dawn Phenomenon effectively The Dawn Phenomenon is a common challenge in diabetes management, and understanding its causes and characteristics is essential for developing effective treatment strategies. By adjusting insulin doses and using appropriate management techniques, individuals with diabetes can better control their blood glucose levels and reduce the risk of complications.
From the Research
Definition and Prevalence of the Dawn Phenomenon
- The Dawn Phenomenon is a term used to describe hyperglycemia or an increase in the amount of insulin needed to maintain normoglycemia, occurring in the absence of antecedent hypoglycemia or waning insulin levels, during the early morning hours 2.
- Approximately 54% of patients with type 1 diabetes and 55% of patients with type 2 diabetes experience the dawn phenomenon 2.
- The phenomenon is characterized by an increase in fasting levels of plasma glucose or insulin requirements between 5 and 9 a.m. 3.
Pathogenesis and Mechanisms
- The most likely pathogenic mechanism underlying the dawn phenomenon is growth hormone-mediated impairment of insulin sensitivity at the liver and muscles 2.
- However, the exact biochemical pathways involved are unknown 2.
- Some studies suggest that the increased need for insulin in the morning may be related to a sleep-associated fall in hepatic glucose output, with a return to basal production rates on arousal in the morning 4.
Clinical Relevance and Management
- The dawn phenomenon contributes directly and significantly to the blood glucose maximum and indirectly, in some cases, to nocturnal hypoglycemia 5.
- Therapeutic decisions aimed at correcting fasting hyperglycemia should take into account the variability and magnitude of the dawn phenomenon within individual patients 2.
- Successful insulinization appears to minimize the effects of the dawn phenomenon 2.
- Increasing the bedtime doses of hypoglycemic agents with nighttime peaks in action may correct early morning hyperglycemia but be associated with undesirable nocturnal hypoglycemia 2.
- Targeted continuous subcutaneous insulin infusion programming can facilitate the prevention of early morning hyperglycemia in selected patients 2, 6.