[The predictive value of melanin-concentrating hormone combined with other related biomarkers in cerebrospinal fluid in preoperative cognitive dysfunction of elderly patients].

Objective

To explore the predictive value of cerebrospinal fluid melanin-concentrating hormone (MCH) combined with other related biomarkers in preoperative cognitive dysfunction of elderly patients.

Methods

A total of 80 patients who underwent elective hip or knee replacement under intravertebral anesthesia in Chifeng Municipal Hospital, Inner Mongolia, from March to November 2022 were prospectively included, with 32 males and 48 females, and aged 65-85 (70.7±5.2) years old. According to the evaluation results of the Montreal Cognitive Assessment (MoCA), patients were divided into the preoperative cognitive dysfunction (n=23) and control (n=57) groups. The levels of MCH, amyloid-β 40 (Aβ40), amyloid-β 42 (Aβ42), and phosphorylated tau protein (p-tau) in cerebrospinal fluid were determined by enzyme-linked immunosorbent assay (ELISA). The receiver operating characteristic (ROC) curve was drawn to evaluate the predictive value of each biomarker separately or in combination for preoperative cognitive dysfunction. Spearman's rank correlation analysis was utilized to test the correlation between the level of each biomarker and MoCA scores.

Results

The levels of MCH, Aβ40, Aβ42, p-tau, and Aβ42/p-tau in the preoperative cognitive dysfunction group were (35.53±5.94) μg/L, (39.21±9.18) ng/L, (221.83±43.17) ng/L, (42.64±9.74) ng/L, and 5.53±1.92, and the levels of these biomarkers in the control group were (28.74±4.90) μg/L, (36.37±7.87) ng/L, (280.23±45.67) ng/L, (35.00±9.27) ng/L, and 8.62±2.78, respectively. Compared with the control group, the levels of cerebrospinal fluid MCH and p-tau in the preoperative cognitive dysfunction group were significantly increased (all P<0.01), and the levels of Aβ42 and Aβ42/p-tau were significantly decreased (all P<0.001). MCH and Aβ42/p-tau provided higher predictive values. The area under the curve (AUC) of MCH and Aβ42/p-tau were 0.807 (95%CI: 0.703-0.911) and 0.842 (95%CI: 0.741-0.943), the sensitivity were 78.3% and 87.0%, and the specificity were 75.4% and 94.7%. MCH combined with Aβ42/p-tau have the higher AUC of 0.915 (95%CI: 0.837-0.992), the sensitivity (87.0%) and specificity (86.0%) were both high, which had a higher predictive value. The levels of cerebrospinal fluid MCH and p-tau were negatively correlated with MoCA score (r=-0.467, -0.321, all P<0.01), and the levels of Aβ42 and Aβ42/p-tau were positively correlated with MoCA score (r=0.480, 0.520, all P<0.001).

Conclusion

The increase in cerebrospinal fluid MCH levels is associated with preoperative cognitive dysfunction in elderly patients. MCH combined with Aβ42/p-tau has the greatest predictive value.