Blood Sugar Plummets, Heart Risk Climbs

Diabetes patients with severe hypoglycemia may have double the likelihood of cardiovascular disease

(RxWiki News) Diabetes patients have to keep a watchful eye on their blood sugar level. If it dips extremely low, they can run the risk of developing a host of health issues, including heart disease.

When diabetes patients don't eat enough, take too much medication or drink alcohol, they can get hypoglycemia, which literally means “low blood sugar.” The main result is that the brain does not get enough glucose (blood sugar), and that can cause impairment. Severe hypoglycemia can lead to seizures, coma and even death.

A new investigation adds to previous research showing that hypoglycemia may also increase the possibility of getting cardiovascular disease, more commonly known as heart disease.

"Check your blood sugar regularly if you are diabetic."

Atsushi Goto, MD, senior researcher, Department of Diabetes Research, Diabetes Research Center, National Center for Global Health and Medicine in Tokyo, led an international team analyzing data from six studies representing 903,510 individuals with type 2 diabetes.

These researchers recorded the diabetes patients' age, gender, duration of diabetes, cardiovascular disease history, insulin use, BMI (a measure used to determine if a person is a healthy weight) and smoking status.

Based on their meta-analysis of the data, the authors found that severe hypoglycemia is associated with approximately twice the risk of cardiovascular disease.

The researchers wrote that the link between hypoglycemia and cardiovascular disease had been explained in previous studies by the patient having one or more other serious illnesses. Dr. Goto and his team believe this is unlikely. They did not find that comorbid severe illness (another disease occurring at the same time) was "...extremely strongly associated with both severe hypoglycemia and cardiovascular disease."

The scientists detailed biological reactions to hypoglycemia that might trigger cardiovascular disease, including inflammation and endothelial (related to the inner lining of blood vessels) dysfunction.

This study's findings support evidence for using individualized blood sugar targets in people with type 2 diabetes. The authors pointed out that certain intensive therapies for blood sugar control might increase the risk of severe hypoglycemia.

This study also supports the use of glucose-lowering agents that are less likely to cause hypoglycemia (for example, metformin — brand names Glucophage, Glumetza, Fortamet and Glucophage XR).

"Importantly, many severe hypoglycemic episodes are preceded by a change in food intake, suggesting that such [hypoglycemic] episodes could be prevented by behavioral changes," wrote Dr. Goto and his colleagues. "In addition, particularly for patients treated with insulin, self monitoring of blood glucose can be useful in preventing hypoglycemia."

This study was published online July 30 in BMJ. This work was funded by health sciences research grants cardiovascular diseases and diabetes mellitus from the Ministry of Health, Labour and Welfare of Japan.

Review Date: 
July 29, 2013