Incidence, Risk Factors, and Sequelae of Post-kidney Transplant Delirium

Abstract

Frail kidney transplant (KT) recipients may be particularly vulnerable to surgical stressors, resulting in delirium and subsequent adverse outcomes. We sought to identify the incidence, risk factors, and sequelae of post-KT delirium. We studied 125,304 adult KT recipients (1999-2014) to estimate delirium incidence in national registry claims. Additionally, we used a validated chart abstraction algorithm to identify post-KT delirium in 893 adult recipients (2009-2017) from a cohort study of frailty. Delirium sequelae were identified using adjusted logistic regression (length of stay ≥2 weeks and institutional discharge [skilled nursing or rehabilitation facility]) and adjusted Cox regression (death-censored graft loss and mortality). Only 0.8% of KT recipients had a delirium claim. In the cohort study, delirium incidence increased with age (18-49 years old: 2.0%; 50-64 years old: 4.6%; 65-75 years old: 9.2%; and ≥75 years old: 13.8%) and frailty (9.0% versus 3.9%); 20.0% of frail recipients aged ≥75 years old experienced delirium. Frailty was independently associated with delirium (odds ratio [OR], 2.05; 95% confidence interval [95% CI], 1.02 to 4.13; =0.04), but premorbid global cognitive function was not. Recipients with delirium had increased risks of ≥2-week length of stay (OR, 5.42; 95% CI, 2.76 to 10.66;<0.001), institutional discharge (OR, 22.41; 95% CI, 7.85 to 63.98; <0.001), graft loss (hazard ratio [HR], 2.73; 95% CI, 1.14 to 6.53; =0.03), and mortality (HR, 3.12; 95% CI, 1.76 to 5.54;<0.001). Post-KT delirium is a strong risk factor for subsequent adverse outcomes, yet it is a clinical entity that is often missed.

Implications of Frailty for Peritransplant Outcomes in Kidney Transplant Recipients

“…During the recovery period, complications may arise which further reduce physical performance. McAdams-DeMarco et al outlined mechanisms by which frail transplant recipients may be prone to transplant complications, including increased hospitalization 21 , immunosuppression intolerance 29 , and delirium 30 . A threshold, or thresholds, for frailty may exist for which certain frail candidates are better off remaining on dialysis and others should only accept living donor kidneys to minimize the extent of peritransplant physiologic stress.…”

“…Transplant centers under-recognize cognitive deficits, such as delirium, to which frail transplant recipients are particularly prone 30 . Targeted efforts to address cognitive deficits in frail transplant recipients include better delirium prevention and treatment along with targeted measures for medication safety and adherence.…”

Prevalence of frailty among kidney transplant candidates and recipients in the United States: Estimates from a National Registry and Multicenter Cohort Study

“…In addition, using national registry data, we estimated that 8.2% of LDKT recipients and 17.8% of DDKT recipients in the United States were frail at the time of transplantation. Our results highlight the importance of identification of recipients at the time of transplantation, given that one in five KT recipients will be at an increased odds of delirium and longer length of stay, increased risk of delayed graft function, early hospital readmission, immunosuppression intolerance, cognitive decline, and mortality . Identification of these vulnerable patients can help clinicians target those patients to mitigate poor outcomes after KT, and quantifying the national prevalence of frailty in KT candidates and recipients is important for resource allocation planning.…”

“…Based on previous cohort studies, frailty is prevalent in 12%‐20% of kidney transplant (KT) candidates and is associated with decreased listing for KT, waitlist mortality, decreased transplantation rates after listing, and poor health‐related quality of life . Furthermore, frailty in KT recipients is associated with poor outcomes following KT such as delirium, longer length of stay, early hospital readmission, immunosuppression intolerance, poor health‐related quality of life, cognitive decline, and mortality . Yet these estimates are from multicenter cohort studies, and national prevalence estimates of frailty may vary from these studies due to differences in KT candidate and recipient populations across the United States.…”

National Trends in Liver Transplantation in Older Adults

“…Outcomes LOS was defined as the duration of hospitalization during the initial transplant episode and analyzed as a binary variable of 2 weeks or less versus more than 2 weeks using adjusted multiple logistic regression-a cut-off previously used in abdominal solid organ transplantation. 28,29 Acute rejection within the first year after LT was analyzed as a binary variable using adjusted multiple logistic regression. All-cause graft loss and mortality were estimated at 1, 3, and 5 years using the Kaplan-Meier method for each time stratum.…”