Cognitive Impairment in CMV Seropositive and CMV Seronegative Deceased Donor Kidney Transplant Recipients

Abstract

Background: Kidney transplant recipients (KTRs) experience a high burden of cytomegalovirus infection (CMV R⁺) and long-term premature cognitive aging. We tested whether CMV was associated with post-KT cognitive impairment.

Methods: In a 2-center prospective cohort study of 574 KTRs (mean age: 54.7 y), we obtained CMV donor/recipient (D/R) serostatus and measured pre- and post-KT cognitive function using the Modified Mini-Mental State Examination. We estimated post-KT global cognitive function trajectories by CMV serostatus using adjusted mixed effect models with linear spline terms.

Results: Two hundred twenty-two (38.6%) recipients were CMV D⁺/R⁺, 100 (17.4%) were CMV D⁺/R^-, 153 (26.6%) were CMV D^-/R⁺, and 99 (17.2%) were CMV D^-/R^-. At the time of KT, there were no significant differences in global cognitive function scores among KTRs irrespective of CMV D/R status. Cognitive function equally improved in all CMV D/R groups during the first 3 y post-KT (slope = 0.62 points/year; 95% confidence interval [CI], 0.17-1.07). However, during years 3-8 post-KT, the global cognitive function score trajectories significantly declined in the CMV D⁺/R⁺ KTRs (slope = -3.51 points/year; 95% CI, -5.07 to -1.95) but not in the other groups, including CMV D^-/R^- (slope = 0.44 points/year; 95% CI, -2.12 to 3.00; P = 0.01), CMV D^-/R⁺ (slope = 0.13 points/year; 95% CI, -1.83 to 2.09), or CMV D⁺/R^- (slope = 0.01 points/year; 95% CI, -1.87 to 1.89).

Conclusions: CMV D⁺/R⁺ KTRs may be at elevated risk for post-KT cognitive impairment; clinicians may prioritize early interventions in this population.

FIGURE 1.

Unadjusted estimates of post-KT trajectories of 3MS examination by CMV status (n = 574). Unadjusted quadratic prediction of global cognitive function by CMV serostatus among KTRs (n = 925). Global cognitive function trajectories (3MS examination scores) did not differ between the different groups at the time of KT. Cognitive trajectories improved among all KTRs in the short term. The long-term trajectories of global cognitive function scores post-KT (years 3–8) differed by CMV serostatus. CMV D⁺/R⁺ KTRs experienced significant impairment in cognitive trajectories; however, CMV D^–/R^– KTRs experienced no significant change in cognitive function trajectories. CMV, cytomegalovirus; KT, kidney transplant; KTR, kidney transplant recipient; 3MS, Modified Mini-Mental State;