Perioperative Probiotic Treatment Attenuates Postoperative Cognitive Dysfunction In Elderly Patients Undergoing Hip Or Knee Arthroplasty: A Randomised, Double-blind, And Placebo-controlled Trial

Objective: To investigate the preventive and therapeutic effect of perioperative probiotics treatment on POCD in elderly patients undergoing hip or knee arthroplasty.Methods: We conducted a randomized,double-blind,placebocontrolled study in the third xiangya hospital of central south university.From March 16,2021 to February 25,2022,a total of 106 elderly patients over 60 years old who scheduled for elective hip and knee replacement were recruited and randomly received probiotics(four capsules,twice/day)or placebo(same as probiotics).Cognitive function was assessed with a battery of 11 neuropsychological tests on the admission day and the 7th day after surgery,respectively.The mild postoperative cognitive dysfunction was defined as a decrease of 1～2 standard deviation of two or more neuropsychological tests from admission baseline.The major postoperative cognitive dysfunction was defined as a decrease of more than2 standard deviation from baseline.Results: Among 106 patients,96 were finally analyzed(7 canceled surgery,2 withdrew consent,1 dead post-surgery).The results shows that the incidence of postoperative cognitive dysfunction was significantly lower in the probiotic group than in the placebo group(12/45[26.7%] vs.29/51[56.9%],P=0.003).The incidence of mild postoperative cognitive dysfunction was also significantly lower in the probiotic group than in the placebo group(11/45[24.4%] vs.24/51[47.1%],P=0.022).There was no significant difference in the incidence of major postoperative cognitive dysfunction between the two groups(1/45[2.2%] vs.5/51[9.8%],P =0.209).The incidence of mild decline in Hopkins verbal learning testrevised(5/45[11.1%] vs.17/51[33.3%],P = 0.01)and Hopkins verbal learning test-revised delayed recall test(6/45[13.3%] vs.20/51[39.2%],P= 0.004)were significantly lower in the probiotics group than in the placebo group.The incidence of mild decline in Hopkins verbal learning test-revised discrimination index was also significantly lower in the probiotics group than in the placebo group(1/45[2.2%] vs.9/51[17.6%],P= 0.018).These three tests constitute a brief neuropsychological tests battery,which had a diagnostic consistency of 0.57,sensitivity of 0.56 and specificity of 1.Conclusion: perioperative probiotic treatment could attenuates postoperative cognitive dysfunction and improve performance on verbalrelated tests in elderly patients undergoing hip or knee arthroplasty.