TUESDAY, Nov. 27, 2007 (HealthDay News) -- An infusion of glucose, insulin and potassium, a treatment thought to help people right after they have had a heart attack, actually increases the immediate risk of heart failure and death for some patients, a new study shows.
Previous research has produced mixed results, with smaller studies supporting the use of GIK therapy, as the treatment is known, and one larger study showing no effect on the death risk 30 days after a heart attack.
However, patients with an ST-segment elevation myocardial infarction, a type of heart attack commonly known as STEMI that shows a particular electrical pattern, should not be given the infusion right away because that increased risk lingers for them in the first three days after diagnosis, the researchers said in a statement.
"GIK therapy increased levels of glucose, potassium, and net fluid gain post-infusion, all three of which predicted death after adjusting for multiple confounders. Adjusting for glucose, potassium, and net fluid gain eliminated the apparent increase in mortality at 3 days observed with GIK infusion, suggesting a direct association with these factors. Administration of GIK infusion within 4 hours of symptom onset yielded no benefit compared with later initiation," the authors wrote.
Their report is published in the Nov. 28 issue of the Journal of the American Medical Association.
The research team, which included scientists from Argentina and Emory University in Atlanta, analyzed data from two separate trials of almost 23,000 STEMI patients. Although the researchers found no difference in outcome at 30 days and six months, when they looked at the first few days following a heart attack, they discovered an increased risk of both heart failure and death in the patients who received the infusions. In the first three days, there were 1,509 incidents of heart failure or death (15.8 percent) in the infusion group, compared with 1,388 incidents of heart failure or death (14.5 percent) in the control group.
The researchers noted that this largest-ever analysis "demonstrates that GIK infusion has no effect on any important clinical endpoint through 30 days following STEMI. However, contrary to our pre-specified hypothesis, we observed a higher rate of death and the composite of death or heart failure at 3 days in patients allocated to GIK therapy compared with control."
The American Heart Association has more on heart attack treatments.