Observational cohort study examining apolipoprotein E status and preoperative neuropsychological performance as predictors of post-operative delirium in an older elective arthroplasty population

Abstract

this study challenges the assertion that ApoE4 genotype predicts post-operative delirium. It replicates previous work suggesting cognitive impairment predicts post-operative delirium and shows for the 1st time that simple cognitive tests can be as effective as more detailed tests.

Neurovascular and immune mechanisms that regulate postoperative delirium superimposed on dementia

“…79 Similarly, in older adults undergoing elective primary hip or knee arthroplasty, APOE genotype and postoperative delirium were not associated. 80 However, Ely et al…”

Pre-operative biomarkers and imaging tests as predictors of post-operative delirium in non-cardiac surgical patients: a systematic review

“…Hypoleptinaemia is an independent predictor of POD [OR 0.385, CI 0.28–0.517].Yes. Sensitivity 72.2%, Specificity 91.7%Cunningham, 2017, UK [19]PC315> 65Elective hip or knee replacementNoYesSerum ApoE4 allele carriage and neuropsychological testsCAM, D1,2,376.9 yr., 65%74 yr., 27.1%ApoE4 genotype is not associated with POD.NoLeung, 2007, USA [20]PC190> 65Elective major non-cardiacNoYesSerum apolipoprotein (APOE) genotypeCAM, D1–274.2 yr., NR72.3 yr., NRPresence of at least one copy of APOE e4 allele is associated with increased risk of POD that persists 2 days post-op.(OR 3.64, 95% CI 1.51–8.77).YesVasunilashorn, 2015, USA [21]PC557> 70Any Elective major non-cardiacNoSensitivity analyses performed to test if dementia has any influence on association between ApoE and POD.Serum Apolipoprotein E: e2, e4 carrier vs non-carrier and three category ApoE genotypes (e3e3, e3e4, e4e4, e2e2, e3e2)CAM and validated chart review dailyApoE genotype has no association with incidence, severity or duration of POD, RR for E4 = 1.0, CI 0.7–1.NoTorbergsen, 2015, Norway & Scotland [22]PC115NREmergency hip fractureNoYesSerum vitamin levels (Vitamin A, B1, B6, vitamin B12, Folic acid, vitamin C, D, K)CAM, D1–584.8 yr., 71%80.6 yr., 79%Vitamin D deficiency (< 50 nmol/L) was independent predictor of POD. (Mean Vitamin D in POD vs. no-POD, 41 vs. 52 nmolL −1 , P = 0.05).YesScholtens, 2017, Netherlands [23]PC144> 65Emergency hip fractureNoNoMorning plasma melatoninCAM85.5 yr., 75%82.5 yr., 69%Morning melatonin not associated with POD ( p = 0.35)NoScholtens, 2016, Netherlands [7]PC60> 65Emergency hip fractureYesNo but confounders (age and cognitive impairment) analysed and did not show any difference in CSF melatonin levels.CSF melatoninDelirium Observation Screening Scale, and DSM-IV, NS86.4 yr., 83.3%83.4 yr., 66%Pre-operative CSF melatonin did not differ between POD and no-POD groups.…”

“…Five studies were major elective orthopaedic surgery [14, 16, 17, 19, 37], 14 emergency hip fracture surgery [7, 9, 11, 18, 22, 23, 26–29, 31–33], 10 major non-cardiac surgery [8, 10, 12, 20, 21, 25, 30, 34–36], 3 general surgery [13, 15, 40], 1 spine surgery [24], 1 vascular surgery [38] and 1 lung resection surgery [41]. All studies that examined CSF biomarkers involved emergency hip fracture patients.…”

“…The ApoE4 allele is most vulnerable to degradation compared to other isoforms, hence it carries the main genetic risk factor for late onset Alzheimer’s disease and is associated with greater risk of amyloid plaque deposition and cerebral amyloid angiopathy [44]. One study reported that the presence of one copy of the e4 allele increased risk of POD that persisted for 2 days post-operatively (28.3% vs. 11.1%; P = 0.005) [20], however two more recent studies reported no association [19, 21]. Interestingly, a recent systematic review of ApoE4 association with delirium concluded no significant association [45].…”

Sevoflurane Versus Isoflurane for Postoperative Cognitive Dysfunction of Patients Undergoing Major Cardiac Surgeries: A Prospective Cohort Study

“…1 The incidence of postoperative cognitive dysfunction is up to 40 % in older adults. 2 This large difference in incidence rate is observed across studies due to the difference in study design, time point of postoperative cognitive dysfunction assessment, 3 type of surgeries, 4 type of anesthesia, 5 patient demographics, 2 apolipoprotein E4 status, 6 cerebral oxygenation 7 and the other clinical characters of patients. Although postoperative cognitive impairment is common in old adults, general anesthetic-induced postoperative cognitive dysfunction can also occur in middle and younger-age.…”