A1c’s rise during the holidays and remain elevated.
The lack of long-term control of blood sugar levels that puts diabetics at risk of complications stems largely from lapses in eating and exercise habits during the winter holiday season, new research indicates.
Investigators from Taiwan monitored glycosylated hemoglobin — which reflects the degree of glucose control over time — in people with type 2 diabetes, and found that glycosylated hemoglobin (called A1C) concentrations tended to increase during the winter months. This was not corrected during the summer months.
Consequently, seasonal splurges may pose serious dangers to diabetics, by causing their A1C to build slowly over time, the team cautions.
In people with type 2 diabetes, the most common form of the disease, A1C tends to rise over time, increasing the risk of heart disease, kidney problems, blindness and other complications of their disease.
To investigate whether the A1C increase occurs largely during the winter holiday season, Dr. Harn-Shen Chen of the Taipei Veterans General Hospital and colleagues periodically checked A1C levels in 110 type 2 diabetics from November to April.
In Chinese culture, the winter holiday season generally starts at the winter solstice on December 23, and continues until the Lantern Festival in February. Like other nationalities, the Chinese typically celebrate the holiday season by eating salty meals, drinking alcohol and skipping their normal exercise regimen.
Ideally, A1C levels should be about seven percent or lower. The investigators found that A1C levels increased by roughly 0.2 percent over the holiday season, rising to approximately 7.5 percent during the month of February.
Moreover, when the researchers checked A1C levels in 90 participants who returned the following winter season, they found no significant change in A1C levels, suggesting that the increases are not corrected during the summer months, and could therefore accumulate over time.
“The cumulative effects of the yearly A1C gain during the winter holidays are likely to contribute to the substantial increase in A1C that frequently occurs among type 2 diabetic subjects,” the authors write in the journal Diabetes Care.
Over time, these seasonal spikes in blood sugar could “result in markedly increased blood glucose levels in a few years,” they add. Diabetes Care, February 2004.