Neurocognitive changes after lung transplantation

Abstract

Rationale: Neurocognitive impairments are associated with reduced quality of life and may adversely affect medical compliance, but their prevalence after lung transplantation has not been extensively studied.

Objectives: To examine the frequency of neurocognitive impairment after lung transplantation and to examine perioperative factors affecting post-transplant neurocognitive function.

Measurements and main results: We performed serial assessments of neurocognitive function in a consecutive series of 47 subjects who received transplants between March 2013 and November 2013 (45% women; mean age, 53.5 ± 17.2 yr). Neurocognitive function was assessed using a composite measure including the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) total score and Trail Making Test parts A and B obtained before transplant, at hospital discharge, and 3 months after discharge. The presence of neurocognitive impairment was assessed using the Montreal Cognitive Assessment Battery (MoCA), and in-hospital delirium was assessed using the Confusion Assessment Method. Results demonstrated that neurocognitive performance initially worsened among non-cystic fibrosis patients and improved over follow-up (P = 0.002). Time effects were strongest on Trail Making Test part B (P < 0.001) and the RBANS (P = 0.054). Participants who exhibited delirium during their hospitalization showed poorer performance during follow-up assessments (P = 0.006). Examination of cognitive impairment rates demonstrated that 21 participants (45%) exhibited neurocognitive impairment (MoCA < 26) before lung transplant, whereas 27 (57%) participants exhibited impairment after transplantation, and 19 (57%) participants continued to neurocognitive impairment during a 3-month follow-up.

Conclusions: Neurocognitive impairments are prevalent among lung transplant candidates and appear to worsen in some patients after transplant. Delirium during hospitalization is associated with worse neurocognitive function after transplant among patients without cystic fibrosis.

Keywords: delirium; lung transplantation; neurocognitive performance.

Figure 1.

Flowchart of participant assessment schedule.

Figure 2.

Changes in neurocognitive function after transplantation among patients with cystic fibrosis (CF) (blue) and patients without CF (red). Neurocognitive performance is displayed as percentile performance based on demographically corrected normative data. FU = follow-up; RBANS = Repeatable Battery for the Assessment of Neuropsychological Status; TMT-B = Trail Making Test part B.

Figure 3.

Changes in neurocognitive function after transplantation among non–cystic fibrosis patients who were or were not delirious after transplant. Data are adjusted for age, education, and the Charlson comorbidity index. F/U = follow-up.