Duke activity status index is not predictive of outcomes after kidney transplantation: a retrospective observational study

TL;DR

The Duke Activity Status Index does not predict outcomes after kidney transplants, suggesting it may not be useful for assessing transplant candidates.

Contribution

This study is the first to evaluate the Duke Activity Status Index's predictive value specifically for kidney transplantation outcomes.

Findings

The Duke Activity Status Index was not predictive of delayed graft function or unplanned critical care admission.

It also failed to predict mortality, graft loss, or post-transplant complications.

The index may have limited utility in assessing functional capacity for kidney transplant candidates.

Abstract

Reduced functional capacity increases the risk of adverse outcomes after kidney transplantation. The Duke Activity Status Index is a measurement of physical function, previously reported as being predictive of adverse outcomes after major non-cardiac surgery. This study assessed the ability of the Duke Activity Status Index to predict adverse outcomes for patients undergoing kidney transplantation.

Adult kidney transplant recipients with a Duke Activity Status Index calculated at time of listing for transplantation in Northern Ireland between 2019 and 2024 were analysed. Dichotomous outcomes (delayed graft function, unplanned critical care admission, 30-day hospital re-admission, 30-day severe postoperative complication, 30-day cardiovascular complication) were analysed using multivariate logistic regression. Post-transplant length of stay was assessed using multivariate linear regression. All-cause mortality and death-censored graft loss were evaluated using Cox proportional hazard regression models.

Data was available for 408 kidney transplant recipients. Duke Activity Status Index was not predictive of delayed graft function (aOR 0.99 (95% CI 0.66–1.01) p = 0.359), unplanned critical care admission (aOR1.00 (95% CI 0.97–1.04), p = 0.866), length-of-stay post-transplant, 30-day hospital re-admission (aOR1.01 (95% CI 0.99–1.03), p = 0.457), 30-day severe postoperative complication (aOR 1.01 (95% CI 0.99–1.03) p = 0.489), 30-day cardiovascular complication (aOR 0.99 (95% CI 0.93–1.06), p = 0.850), all-cause mortality (aHR 1.00 (0.96–1.04), p = 0.89) or death-censored graft loss (aHR 0.97 (95% CI 0.93–1.01), p = 0.14).

In this cohort, the Duke Activity Status Index was not an independent predictor of short or long-term adverse outcomes following kidney transplantation. These findings suggest that the Duke Activity Status Index may have limited utility in assessing functional capacity in waitlisted kidney transplant candidates.

Not applicable.

Figures