Background: Frailty has been suggested as a possible risk factor for postoperative delirium (POD). However, results of previous studies were not consistent. We performed a meta-analysis of cohort study to evaluate the above association.
Methods: Relevant studies were obtained via systematic search of PubMed, Embase, SCOPUS, and Web of Science databases. Only studies with multivariate analysis were included. A random-effect model incorporating the potential heterogeneity was used to combine the results.
Results: Fifteen cohort studies including 3250 adult patients who underwent surgery were included, and the prevalence of frailty was 27.1% (880/3250) before surgeries. Overall, POD occurred in 513 patients (15.8%). Pooled results showed that frailty was associated with a higher risk of POD (adjusted odds ratio [OR]: 3.23, 95% confidence interval [CI]: 2.56-4.07, P < 0.001) without significant heterogeneity (P for Cochrane's Q test = 0.25, I2 = 18%). Subgroup analyses showed a more remarkable association between frailty and POD in prospective cohort studies (OR: 3.64, 95% CI: 2.95-4.49, P < 0.001) than that in retrospective cohort studies (OR: 2.32, 95% CI: 1.60-3.35, P < 0.001; P for subgroup difference = 0.04). Moreover, the association was not affected by country of the study, age group of the patient, elective or emergency surgeries, cardiac and non-cardiac surgeries, evaluation instruments for frailty, diagnostic methods for POD, or quality score of the study (P for subgroup difference all > 0.05).
Conclusions: Frailty may be associated with a higher risk of POD in adult population.
Keywords: Cohort studies; Frailty; Meta-analysis; Postoperative delirium.
© 2021. The Author(s), under exclusive licence to Springer Nature Switzerland AG.