Association between serum chemokines levels and delayed neurocognitive recovery after non-cardiac surgery in elderly patients: a nested case-control study.

BACKGROUND

Perioperative neurocognitive disorders encompass delayed neurocognitive recovery (dNCR). Emerging evidence suggests that chemokines play a crucial role in the pathogenesis of various cognitive impairment diseases. However, the association between chemokines and dNCR remains unclear. Therefore, we aimed to investigate the relationship between serum chemokine levels and dNCR in elderly patients undergoing non-cardiac surgery.

METHODS

A total of 144 patients undergoing elective major non-cardiac surgery were accessed in neuropsychological testing 1 day prior to and 1 week following the surgery. Blood samples were collected before the initiation of anesthesia and one hour following the cessation of anesthesia. We employed a retrospective nested case-control study design, utilizing one control per dNCR case. Matching criteria included age (± 5 years), duration of surgery (± 90 min), and baseline MMSE score (± 3). We compared the serum levels of CCL2, CCL5, CCL11, and CXCL8 between the matched dNCR and non-dNCR groups.

RESULTS

dNCR was observed in 31.25% (45 of 144) of the patients seven days post-surgery, resulting in a final matched sample size of 21 pairs. In the preoperative comparison, the serum concentration of CCL11 was significantly higher in the matched dNCR group compared to the matched non-dNCR group (P = 0.039). In the postoperative comparison, the CCL5 concentration was significantly lower in the dNCR than in the non-dNCR group (P = 0.030). When comparing the differences between postoperative and preoperative levels, the absolute change in CCL11 was significantly greater in the dNCR group compared to the non-dNCR group (P = 0.046). Additionally, the postoperative-to-preoperative ratios of CCL5 and CCL11 in the dNCR group were both significantly lower than those in the non-dNCR group (P = 0.046, P = 0.005). There were no significant differences in CCL2 or CXCL8 levels between the two matched groups.

CONCLUSIONS

Serum levels of CCL 5 and CCL 11 significantly decreased in elderly patients with dNCR following non-cardiac surgery, which may contribute to the identification of patients at high risk for dNCR.

TRIAL REGISTRATION

This study was registered on chictr.org.cn (ChiCTR1800014473, 16/01/2018).