Endocrine Abstracts

Previous studies have shown increased hypoglycemia-associated cardiac arrhythmia and mortality in patients with type 2 diabetes and cardiovascular disease.

In this study, we aimed to evaluate the response of gastrointestinal hormones and glucoregulatory hormones to the oral glucose tolerance test in patients who were diagnosed with reactive hypoglycemia and to evaluate the risk of arrhythmia with long-holter ECG measurements in patients with a diagnosis of reactive hypoglycemia. In this prospective observation study, 64 patients (F / M: 42/22) who admitted to our clinic with reactive hypoglycemia-like complaints were subjected to oral glucose tolerance test with mixed meal. Patients with hypoglycemia symptoms who had plasma glucose values below 55 mg/dl in the first 4 hours of postprandial period were considered as reactive hypoglycemia.

Continuous glucose monitoring and 72-hour holter ECG examinations were performed synchronously in these patients. At the same time, prolonged OGTT test was performed in these patients. Glucose, insulin, leptin, glucagon, GLP-1, cortisol levels were evaluated in 0,15,30,60,90,120,180,240,300 minutes. Postprandial median glucose values were at hypoglycemic levels at 180 and 240 minutes.

During the test protocol a decrease of 26 mg/dl glucose in the hypoglycemic period, an increase of 21.4 pg/ml in GLP-1 levels, a decrease of 20.4 U/ml in insulin levels, an increase in glucagon level of 18.9 pg/ml, and an increase in cortisol level of 2.9 µg/dl were detected. Continuous glucose monitoring revealed symptomatic hypoglycemia in 2 of 7 patients (glucose <55 mg/dl). At least one hypoglycemic value was detected in 6 of 7 patients. No biochemical or clinical hypoglycemia was detected in one patient. 11 ectopic ventricular beats were detected in 2 patients with severe hypoglycemia.

Although the symptoms of postprandial hypoglycemia are seen in many individuals in the community, the frequency of reactive hypoglycemia was lower than expected when standard diagnostic tests were applied to these patients. Atrial and ventricular ectopic pulses may be seen in patients with reactive hypoglycemia, although severe cardiac arrhythmia is not observed. The mechanisms involved in the etiology of reactive hypoglycemia have still not been elucidated. We can speculate that the increase in GLP-1 and leptin hormone levels may be responsible for postprandial hypoglycemia.