BACKGROUND/AIMS: To investigate abnormalities in blood electrolyte levels during severe hypoglycemia in Korean patients with type 2 diabetes mellitus (T2DM) in a clinical setting. METHODS: Blood electrolyte levels in adult T2DM patients during severe hypoglycemia were collected from January 1, 2008 to December 31, 2012. Patients who maintained normal serum creatinine and blood urea nitrogen levels were utilized in the study. Severe hypoglycemia was defined as a condition requiring medical assistance, such as administering carbohydrates when serum glucose levels less than 70 mg/dL were observed, in conjunction with other symptoms of hypoglycemia. RESULTS: A total of 1,068 patients who visited the emergency room with severe hypoglycemia were screened, of which 219 patients were included in this study. The incidence of abnormal levels for any electrolyte was 47%. Hypokalemia (< 3.5 mmol/L) was the most common type of electrolyte disturbance observed at 21.9%. A decrease in serum potassium levels was associated with decreases in blood glucose levels (r = 0.151, p = 0.025). During severe hypoglycemia, median blood glucose levels, incidence of tachycardia (> 100 beats per minute) and severe hypertension (> or = 180/120 mmHg) were 30 mg/dL (range, 14 to 62) and 35 mg/dL (range, 10 to 69; p = 0.04), 18.8% and 7.2% (p = 0.02), and 20.8% and 10.2% (p = 0.05) in the hypokalemia and normokalemia groups, respectively. CONCLUSIONS: During severe hypoglycemia, hypokalemia occurred in 21.9% of T2DM patients and was associated with tachycardia and severe hypertension. Therefore, the results suggest that severe hypoglycemia may increase cardiovascular events in T2DM.
Aged ; Aged, 80 and over ; Biomarkers/blood ; Blood Glucose/drug effects/*metabolism ; Diabetes Mellitus, Type 2/blood/diagnosis/drug therapy/*epidemiology ; Emergency Service, Hospital ; Female ; Humans ; Hypertension/chemically induced/epidemiology ; Hypoglycemia/blood/chemically induced/diagnosis/*epidemiology/therapy ; Hypoglycemic Agents/adverse effects ; Hypokalemia/blood/chemically induced/diagnosis/*epidemiology ; Male ; Middle Aged ; Potassium/*blood ; Republic of Korea/epidemiology ; Risk Factors ; Severity of Illness Index ; Tachycardia/chemically induced/epidemiology ; *Water-Electrolyte Balance/drug effects

Hypoglycemia is a major barrier to achieving the glycemic goal in patients with type 2 diabetes. In particular, severe hypoglycemia, which is defined as an event that requires the assistance of another person to actively administer carbohydrates, glucagon, or take other corrective actions, is a serious clinical concern in patients with diabetes. If severe hypoglycemia is not managed promptly, it can be life threatening. Hypoglycemia-associated autonomic failure (HAAF) is the main pathogenic mechanism behind severe hypoglycemia. Defective glucose counter-regulation (altered insulin secretion, glucagon secretion, and an attenuated increase in epinephrine during hypoglycemia) and a lack of awareness regarding hypoglycemia (attenuated sympathoadrenal activity) are common components of HAAF in patients with diabetes. There is considerable evidence that hypoglycemia is an independent risk factor for cardiovascular disease. In addition, hypoglycemia has a significant influence on the quality of life of patients with diabetes. To prevent hypoglycemic events, the setting of glycemic goals should be individualized, particularly in elderly individuals or patients with complicated or advanced type 2 diabetes. Patients at high-risk for the future development of severe hypoglycemia should be selected carefully, and intensive education with reinforcement should be implemented.
Autonomic Nervous System/physiopathology ; Biological Markers/blood ; Blood Glucose/*drug effects/metabolism ; Diabetes Mellitus, Type 2/blood/complications/diagnosis/*drug therapy/physiopathology ; Health Knowledge, Attitudes, Practice ; Humans ; Hypoglycemia/blood/chemically induced/epidemiology/physiopathology/*prevention & control ; Hypoglycemic Agents/*adverse effects ; Incidence ; Patient Education as Topic ; Prevalence ; Prognosis ; Risk Assessment ; Risk Factors