NR2 antibody is associated with quality of life in aortic valve replacement

Background: The relationship between the potential brain injury biomarker N-methyl-D-aspartate receptor antibody and quality of life has never been assessed.

Methods: We measured serum N-methyl-D-aspartate receptor antibody levels preoperatively in patients undergoing aortic valve replacement. Quality of life was scored using the Short Form-36 and European Quality of Life 5-Dimensions questionnaires pre- and postoperatively. We analyzed the antibody levels as a continuous variable and as a dichotomous variable with 1.8 ng mL(-1) as the cutoff.

Results: Fifty-two patients (15 females) with a mean age of 71 ± 8.4 years were recruited for this study. Forty-eight (92%) patients attended the follow-up visit (405 ± 161 days). No mortality or severe neurological event was recorded. In both quality-of-life instruments, the low antibody level group (n = 35) had significantly better scores than the high antibody level group (n = 17) preoperatively. Postoperatively, the scores for both groups improved; however, the low antibody level group continued to score significantly better in most of the physical and mental health domains (p = 0.04 to <0.001). Multiple regression analyses revealed that antibody level and the 1.8 ng mL(-1) cutoff were independently related to quality of life (pre- and postoperatively).

Conclusions: Higher N-methyl-D-aspartate receptor antibody levels in aortic valve replacement patients are independently related to poorer quality of life pre- and postoperatively.