Hypoglycemia Increases Mortality in Hospitalized Patients

December 5th, 2016

PETAH TIKVA, ISRAEL — Whether they have been diagnosed with diabetes mellitus (DM), hospitalized patients often have low blood sugar — which is associated with higher mortality risk immediately and over the long term, according to a new Israeli study.

The research, published in the Journal of Clinical Endocrinology & Metabolism, sought to determine how prognostic implications might differ with spontaneous vs. insulin-related hypoglycemia.

"Hypoglycemia is common among hospitalized patients with and without diabetes mellitus," explained the study's senior author, Amit Akirov, MD, of Rabin Medical Center in Petah Tikva, Israel. "Our findings suggest that hypoglycemia, whether insulin-related or non-insulin-related, is associated with short- and long-term mortality risk."

For the study, researchers looked at 3,000 patients with hypoglycemia, which was defined as blood glucose levels lower than 70 mg/dl, during hospitalization at a 1,330-bed university-affiliated medical center. Researchers evaluated medical records and the hospital's mortality database to investigate the association between hypoglycemia and mortality in the hospitalized patients between January 2011 and December 2013.

Patients were classified into the following six groups:

• non-insulin treated (NITC) and insulin-treated controls (ITC),
• insulin-related hypoglycemia (IH) or severe hypoglycemia (ISH), and
• non-insulin-related hypoglycemia (NIH) and severe hypoglycemia (NISH).

Compared with non-insulin treated controls (NITC), unadjusted hazard ratios for mortality were 1.7 for ITC; 2.2 for NIH; 2.5 for IH, 4.2 for NISH and 3.8 for ISH.

The study found that mortality risk was higher in insulin-treated patients with moderate hypoglycemia — i.e., 40-70 mg/dL — compared to patients without insulin treatment with similar glucose values. With severe hypoglycemia, defined as glucose levels below 40 mg/dl, the increase in mortality risk was similar with insulin-related and non-insulin-related hypoglycemia.

Noting that cause of admission did not affect the association between glucose levels and mortality, study authors concluded, “In hospitalized patients, hypoglycemia, either with insulin or spontaneous, is associated with increased short- and long-term mortality.”

"These data are a timely reminder that hypoglycemia of any cause carries the association with increased mortality,” Akirov added.