Thorac Cardiovasc Surg 2011; 59 - eP142
DOI: 10.1055/s-0030-1269352

Age-dependent differences in postoperative HLA-DR expression in cardiac surgery patients

K Lazouski 1, A Zittermann 1, M Schmidt 1, J Gummert 1, J Börgermann 1
  • 1Herz- und Diabeteszentrum NRW, Ruhr Universität Bochum, Klinik für Thorax- und Kardiovaskularchirurgie, Bad Oeynhausen, Germany

Objective: Advanced age is a risk factor for clinical complications in cardiac surgery. Delayed recovery of human leucocyte antigen (HLA)-DR expression is also associated with complications after cardiac surgery. Little is currently known concerning the effect of age on HLA-DR expression.

Methods: We recruited 26 cardiac surgery patients aged 65 years and less and 24 patients aged 75 years and over. We performed cytoimmunological monitoring preoperatively (t1), immediately after surgery (t2), on postoperative day 1 (t3), day 5 (t4), and day 30 (t5). We measured CD4 and CD8 counts, the CD4/CD8 ratio, the percentage of peripheral blood monocytes with HLA-DR expression, and the absolute numbers of HLA-DR on monocytes.

Results: Initially, the numbers of HLA-DR on monocytes were similar between groups (P=0.924). A nadir was reached at t3 and these values were identical in both groups (31.5% of initial numbers of HLA-DR). At t4, however, the numbers of HLA-DR had returned to only 39.3% of the initial values in the elderly patients but to 47.9% in the younger patients (P=0.05). Until t5, the numbers reached 75.1% of the initial values in the younger patients and 69.2% in the older patients (P=0.420). The percentage of monocytes with HLA-DR expression, CD4 and CD8 counts, and the CD4/CD8 ratio showed no age-dependent differences.

Conclusions: Our data indicate that the numbers of HLA-DR on monocytes do not return to preoperative values until postoperative day 30. In addition, the transient decrease in HLA-DR expression appears to be more pronounced in elderly than in younger patients.