By Jimmy Downs

Tuesday Dec 25, 2012 (foodconsumer.org) -- A new study in International Journal of Cardiology has found that patients who receive coronary artery bypass surgery would have a higher risk for stroke if they have renal dysfunction.

M. J. Holzmann from Department of Emergency Medicine, Karolinska University Hospital and Department of Internal Medicine, Karolinska Institutet in Stockholm, Sweden and colleagues reported that patients who had renal or kidney dysfunction after receiving coronary artery bypass surgery faced up to nearly 80 percent increased risk of stroke, compared with those with normal kidney function.

"Renal dysfunction is associated with increased long-term mortality and incidence of myocardial infarction following coronary artery bypass grafting," the authors state.

The current study was intended to examine the association between renal dysfunction and long-term risk of stroke after coronary artery bypass grafting.

For the study, researchers analyzed data from 29, 057 patients  in the SWEDEHEART registry who underwent primary isolated coronary artery bypass grafting from 2000 through 2008 in Sweden, with no myocardial infarction within 14 days of surgery and no history of stroke.

Renal function was estimated using glomerular filtration rates which were based on the Modification of Diet in Renal Disease equation with a high value indicating a better function.

Patients with glomerular filtration rates 45 to 60, 30 to 45 and 15 to 30mL/min/1.73m(2) were 17, 52, and 79 percent increased risk of any stroke, respectively, compared with those with glomerular filtration rates greater than 60mL/min/1.73m(2).

The strength of the association was similar in both men and women.  

The risk of hemorrhagic stroke was higher than that for ischemic stroke, 2.07-fold vs. 1.55-fold, in patients with glomerular filtration rates 15 to 45mL/min/1.73m(2), compared with glomerular filtration rates greater than 60mL/min/1.73m(2).

The researchers concluded "Renal dysfunction is associated with increased long-term risk of stroke after primary isolated CABG (coronary artery bypass grafting). The impact of renal dysfunction on risk of stroke appears to be similar for both men and women."