Date of Award

Spring 2017

Document Type


Degree Name

Doctor of Philosophy (PhD)


Health Services Research

Committee Director

Mariana Szklo-Coxe

Committee Member

Daniel Russell

Committee Member

J. Catesby Ware

Committee Member

Tina Cunningham


A historic cohort study of kidney transplant recipients with a failed graft was conducted to examine the associations between sleep disorders and kidney transplant outcomes. Adult kidney transplant recipients who were transplanted and failed or died with a functioning graft during the designated study time period (January 1, 1997 to September 1, 2015, inclusive) were included (n=299). The primary independent variables, any sleep disorder and any sleep-disordered breathing disorders, were defined through a diagnosis in a subject’s medical record. Transplant outcomes included: death with a functioning graft, graft survival time, and patient survival time after graft failure.

Chi-square statistics were used to compare the proportion of death with a functioning graft between subjects with versus without any sleep disorder and to help inform the censoring approach for graft survival time. Kaplan Meier survival curves were used to examine the relationship of any sleep disorder to survival time. Cox regression models, examined the adjusted relationship of any sleep disorder to the outcomes, graft survival time and patient survival time after graft failure. Sub-analyses also examined associations between sleep-disordered breathing disorders and these outcomes.

The prevalence of any sleep disorder in this cohort was 20%, with the majority consisting of sleep apnea diagnoses, a sleep-disordered breathing disorder. Given a statistically significant (p≤0.01, adjusted model) sleep disorder by transplant-year heterogeneity, Cox regression models were stratified by transplant-year for the graft survival outcome. Having a sleep disorder, namely, sleep apnea, was associated with a statistically significantly increased risk of graft failure or cardiovascular related death with a functioning graft among patients transplanted in 2009-2015 (adjusted HR=2.94, p

In a single-center cohort of kidney transplant recipients with a failed graft, a sleep apnea diagnosis increased the risk of graft loss nearly three-fold among patients transplanted between 2009-2015. Further research is needed to better understand this relationship and whether prevention strategies, including treating sleep apnea, might increase longevity in kidney transplant patients.