CLINICAL CHEMISTRY AND LABORATORY MEDICINE, vol.44, no.4, pp.471-478, 2006 (SCI-Expanded)
The aims of this study were to determine circulating choline status and its relationship to circulating levels of S-100b protein and neuron-specific enolase, biochemical markers of cerebral injury and cognitive decline, after coronary artery bypass grafting ( CABG) surgery. Preoperatively, patients scheduled for off-pump or on- pump CABG surgery had serum concentrations of 12.0 +/- 0.2 and 11.7 +/- 0.4 mmol/L free choline and 2640 +/- 65 and 2675 +/- 115 mmol/L phospholipid-bound choline, respectively. Serum free and bound choline levels decreased by 22-37% or 34-47% and 16-36% or 31-38% at 48 h after off-pump or on- pump surgery, respectively. Serum S-100b and neuron-specific enolase increased from preoperative values of 0.083 +/- 0.009 and 6.3 +/- 0.2 mg/L to 0.405 +/- 0.022 and 11.4 +/- 0.8 mg/L, respectively, at 0 h postoperatively and remained elevated for 48 h after off-pump surgery. Serum free and bound choline concentrations were inversely correlated with the concentrations of S-100b ( r=-0.798; p<0.001 and r=-0.734; p<0.001) and neuron-specific enolase ( r=-0.840; p<0.001 and r=-0.728; p<0.001). In conclusion, CABG surgery induces a decline in serum free and phospholipid-bound choline concentrations. The decreased serum choline concentrations were inversely correlated with the elevated levels of circulating cerebral injury markers. Thus, a decline in circulating choline may be involved in postoperative cognitive decline.