Peri-Operative Risk Factors Associated with Post-Operative Cognitive Dysfunction (POCD): An Umbrella Review of Meta-Analyses of Observational Studies

Abstract

This umbrella review aimed to systematically identify the peri-operative risk factors associated with post-operative cognitive dysfunction (POCD) using meta-analyses of observational studies. To date, no review has synthesised nor assessed the strength of the available evidence examining risk factors for POCD. Database searches from journal inception to December 2022 consisted of systematic reviews with meta-analyses that included observational studies examining pre-, intra- and post-operative risk factors for POCD. A total of 330 papers were initially screened. Eleven meta-analyses were included in this umbrella review, which consisted of 73 risk factors in a total population of 67,622 participants. Most pertained to pre-operative risk factors (74%) that were predominantly examined using prospective designs and in cardiac-related surgeries (71%). Overall, 31 of the 73 factors (42%) were associated with a higher risk of POCD. However, there was no convincing (class I) or highly suggestive (class II) evidence for associations between risk factors and POCD, and suggestive evidence (class III) was limited to two risk factors (pre-operative age and pre-operative diabetes). Given that the overall strength of the evidence is limited, further large-scale studies that examine risk factors across various surgery types are recommended.

Association of sleep quality on the night of operative day with postoperative delirium in elderly patients

“…The potential covariates for the multivariable regression were selected based on univariate analysis, clinical relevance, and previous literature associations with POD. 28,29 Potential confounders included age, BMI, cerebrovascular disease, intra-operative midazolam and dexmedetomidine, surgical sites (general, thoracic, orthopaedic, urological or gynaecological), surgical duration, blood loss, baseline laboratory values, for example, Hb, and pain NRS at rest. 30 The entire patient cohort was also analysed using a subgroup analysis based on predetermined subgroups.…”

“…In the multivariable logistic regression model, we employed a forced entry approach, where all selected variables were included simultaneously in the model. The potential covariates for the multivariable regression were selected based on univariate analysis, clinical relevance, and previous literature associations with POD 28,29 . Potential confounders included age, BMI, cerebrovascular disease, intra-operative midazolam and dexmedetomidine, surgical sites (general, thoracic, orthopaedic, urological or gynaecological), surgical duration, blood loss, baseline laboratory values, for example, Hb, and pain NRS at rest 30 …”

Melanin-Concentrating Hormone Is Associated With Delayed Neurocognitive Recovery in Older Adult Patients With Preoperative Sleep Disorders Undergoing Spinal Anesthesia

“…A sample size calculation was performed using G*Power 3.1.9.6 (Franz Faul, Universitat Kiel). According to previous studies and considering that the older adult patients with preoperative sleep disorders included in this study are at high risk for DNR, 2,3 we assumed that 30% to 40% of patients experience DNR after surgery. According to our preliminary testing, we assumed that the CSF MCH levels would be 50 pg/mL in the DNR group and 40 pg/mL in the non-DNR group with a common SD value of 10 (effect size d = 1), and the plasma MCH levels would be 30 pg/mL in the DNR group and 25 pg/mL in the non-DNR group with a common SD value of 8 (effect size d = 0.625).…”

“…1 The incidence of DNR ranges from 9.1% to 45%, which seriously affects the perioperative brain health of older adult patients. 2,3 Sleep disorders are critical risk factors among the various risk factors for DNR after surgery. [4][5][6] Meanwhile, aging is an independent risk factor for sleep disorders.…”

“…Studies have explored the risk factors for perioperative sleep disorders, 10,11 while other studies have also explored the risk factors affecting postoperative cognitive outcomes. 2,12,13 However, no study has explored the specific risk factors for DNR in patients with preoperative sleep disorders. Considering the relationship between sleep and postoperative cognitive function, especially in older adult patients, 3,6,14,15 it is necessary to link these 2 main risk factors (preoperative sleep disorders and DNR) that impair the perioperative brain health to explore potential biomarkers.…”