No Link Between Hypoglycemia and Mortality or Stroke/MI in Diabetic AMI Patients: DIGAMI-2 Analysis

Shelley Wood

May 07, 2009

May 7, 2009 (Stockholm, Sweden) — A new analysis from the DIGAMI-2 study suggests that hypoglycemia during hospitalization for suspected AMI is not, in itself, a risk factor for future adverse events in people with type 2 diabetes [1]. The study is the latest to offer some reassurances to physicians treating hyperglycemia in AMI patients and to suggest that other comorbidities are likely responsible for the development of hypoglycemia during hospital admission.

"These findings underline the safety of using insulin in hyperglycemic patients with type 2 diabetes during the acute phase of a myocardial infarction, provided a careful blood glucose monitoring to ascertain early detection and treatment of hypoglycemic episodes," Dr Linda G Mellbin (Karolinska Institute, Stockholm, Sweden), and colleagues write in the May 2009 issue of Heart.

As previously reported by heartwire, DIGAMI-2 showed no benefit of long-term intensive insulin treatment in terms of survival when compared with usual care. For the current analysis, Mellbin et al looked specifically at whether DIGAMI-2 patients who developed hypoglycemia during their hospitalization were more likely to die or suffer further cardiovascular events over a median of 2.1 years.

Among the 1253 patients enrolled in the study, 111 hypoglycemic episodes occurred among insulin-treated subjects and in three patients treated without insulin. Over the roughly two-year follow-up, 277 patients (22.1%) died, often from CV disease, and 217 (17.3%) had a nonfatal MI or stroke. But as Mellbin et al note, while hypoglycemia was related to mortality in unadjusted analyses, the association disappeared after taking into account such factors as age, sex, smoking, prior MI, heart failure, renal failure, diabetes duration, etc.

Investigators say that their study is the "first report of its kind" to show that there is no proof of a relationship between hypoglycemia and mortality or between hypoglycemia and later stroke/MI.

"The fear of hypoglycemia has been mentioned as an obstacle in attempts to achieve normoglycemia in a long-term as well as in a short-term perspective," the authors conclude. "The present observation indicates that hypoglycemic episodes are less harmful than previously believed, at least in carefully monitored patients."

Commenting on the study for heartwire , Dr Mikhail Kosiborod (Mid America Heart Institute, Kansas City, MO), whose group has also been investigating the link between hypoglycemia and mortality, called the findings "important."

"[They] confirm the conclusions of our recent US-based study--that episodic hypoglycemia does not appear to be directly harmful in patients hospitalized with AMI," he said. "While the authors could not assess the prognosis associated with spontaneous and insulin-induced hypoglycemia separately (due to the smaller patient sample and fewer hypoglycemic events in their study), their observations further validate the notion that hypoglycemia is likely a marker of severe illness, rather than a direct mediator of adverse events."

Mellbin had no relevant disclosures. Kosiborod has previously disclosed having served on the advisory board of Sanofi-Aventis and having received speaking honoraria from the Vascular Biology Working Group and DiaVed.