Attig, Stacie M.

Abstract Introduction Solid organ transplant recipients experience high rates of cognitive impairment; however, little is known about what modifiable factors contribute to cognitive impairment after transplantation, limiting evidence-based treatment options. Insomnia is a sleep disorder that is associated with poor cognitive functioning in healthy adults and is amenable to interventions, but the relationship between insomnia and cognitive impairment after organ transplantation has not been explored. The purpose of this study was to identify relationships between insomnia, sleep characteristics, and perceived cognitive function after organ transplantation. Methods We conducted a descriptive, cross-sectional study of adult (>18 years) transplant recipients. We used the Insomnia Severity Index to measure insomnia, 10 days of continuous wrist actigraphy (Ambulatory Monitoring Inc. MicroMotionlogger) to measure sleep characteristics, and the PROMIS Cognitive Function to elicit perceived cognitive function. Descriptive statistics, Spearman’s Rho correlations, and Pearson’s correlations were used to describe relationships. Results We enrolled 34 participants [Mean age 62.5 years (SD 10.7), 64.7% (n=22) female, 85.3% (n=29) white, 17 liver/9 heart/8 kidney, average time since transplant 4.8 years (SD 4.2)]. 73.3% had clinically significant insomnia [mean ISI: 12.9 (SD 6.9)]. Sleep characteristics were obtained using actigraphy (mean duration: 7.03 hours [SD 1.28], onset latency: 9.16 min [SD 4.90], efficiency: 89.49% [SD 8.96], wake after sleep onset: 49.61 [SD 37.37]). Perceived cognitive function for the sample was worse than that of the general population, with a mean T-score of 45.21 (SD 11.44). Lower perceived cognitive function scores were significantly associated with younger age (rs = -.416, p=.016) and shorter time since transplant (rs =-.386, p=.024). Longer wake after sleep onset (rs =.347, p=.048) and lower sleep efficiency (rs=-.358, p=.041) were associated with lower perceived cognitive function. Lower perceived cognitive function was strongly associated with higher insomnia severity scores (r=.817, p=<.001). Conclusion Insomnia was common in our sample of transplant recipients and was strongly correlated with worse perceived cognitive function. Future research should incorporate objective measures of cognitive functioning and should consider insomnia treatment as a potential intervention to promote optimal cognitive functioning after organ transplantation. Support (if any) Mayo Clinic Center for Clinical and Translational Science.