It may seem obvious to som, but for Type 1 Diabetes patients, a episode of psychological   stress significantly slows the decline in blood sugar concentrations following a spike after food intake - but has no effect on sugar levels during fasting.

While psychological stress has been proposed to affect blood sugar levels in diabetic individuals, studies investigating the potential link have had conflicting results, Dr. Peter Wiesli of the University Hospital of Zurich and colleagues note in the journal Diabetes Care. They therefore conducted the current study to test their hypothesis that the stress response would differ between a fasting period and after eating a meal.

The team compared the effects of stress on 20 fasting patients and another 20 patients who had eaten a standard meal 75 minutes previously. Blood sugar and other indicators were measured for each group on a day a stress test was administered and on a day in which it was not.

The test involved a speech task in which the subjects introduced themselves and applied for a job, and when performed a mental arithmetic task. The stress test produced increases in blood pressure and heart rate in both groups.

Patients were advised to maintain their normal insulin injection schedule. While fasting patients showed no difference in blood sugar levels in response to stress, stress exposure delayed post-meal lowering of sugar concentrations by 45 minutes. This effect appeared about 30 minutes after the stress test and lasted for roughly two hours.

The largest difference between stress and non-stress sugar levels in the group of patients who had eaten was 1.4 mmol/L at 55 and 80 minutes after the test.

“We therefore conclude that acute mental stress should be accepted as a potential explanation for (sugar) excursions, particularly in the context of a preceding meal,” Wiesli and his team write. Patients with Type 1 Diabetes should be aware of the potential for this effect when they experience mental stress after eating, the researchers conclude.

SOURCE: Diabetes Care, August 2005.