Neurocognitive functions of pediatric kidney transplant recipients.

BACKGROUND: End-stage renal disease (ESRD) in children is associated with impaired neurocognitive function and development. However, data on factors associated with neurocognitive dysfunctions in children with kidney transplants are limited. METHODS: We conducted a cross-sectional analysis comparing cognitive functions (using the Woodcock-Johnson International Edition, WJIE) in 35 kidney transplant and 35 healthy control children. Data on laboratory measurements, comorbidities, and social characteristics were collected. RESULTS: Transplant children had significantly worse scores on the intelligence quotient (IQ) test compared with controls [Full Scale IQ score 85 (26) vs 107 (10), p <0.001]. Lower maternal education level was significantly associated with lower WJIE cognitive test scores; however, no association was found between laboratory values and WJIE scores. Among children with kidney transplants, those with medical comorbid conditions had significantly lower Verbal Ability and Full Scale IQ scores. Earlier age of dialysis onset and a longer total time on dialysis (>9 months) were associated with lower test scores. Age-standardized duration of hospitalization was inversely correlated with IQ (r = -0.46, p <0.01) and was an independent significant predictor (Beta = -0.38, p = 0.02) of IQ scores in transplanted children. CONCLUSIONS: Child kidney transplant recipients have neurocognitive function impairments that are associated with markers of socioeconomic status (SES) and factors related to disease severity.

Health-related quality of life and clinical outcomes in kidney transplant recipients.

BACKGROUND: Health-related quality of life (HRQoL) is an important outcome measure in patients with chronic kidney disease. It also has been shown repeatedly to predict mortality in various patient populations. In a prospective cohort study, we assessed the association between HRQoL and long-term clinical outcome in kidney transplant recipients. STUDY DESIGN: Prospective prevalent cohort study. SETTING & PARTICIPANTS: We collected sociodemographic parameters, medical and transplant history, and laboratory data at baseline from 879 prevalent kidney transplant recipients (mean age, 49 ± 13 [standard deviation] years; 58% men; and 17% with diabetes mellitus). PREDICTOR: We assessed HRQoL using the KDQoL-SF (Kidney Disease Quality of Life Short Form) questionnaire and assessed depressive symptoms using the Center for Epidemiologic Studies-Depression Scale. OUTCOMES: All-cause mortality and death-censored transplant loss or death with functioning transplant. Cox regression models and semiparametric competing-risks regression analyses were used to measure associations between HRQoL scores and outcomes. RESULTS: Most examined HRQoL domains were associated with clinical outcome in unadjusted models. After adjusting for several important confounders, the 36-Item Short Form Health Survey (SF-36) Physical Composite Score and Physical Functioning and General Health Perception subscale scores remained independently associated with clinical outcomes. Every 10-point increase in SF-36 Physical Composite Score and Physical Functioning and General Health Perception scores was associated with 18% (HR, 0.82; 95% CI, 0.71-0.95), 11% (HR, 0.89; 95% CI, 0.84-0.94), and 7% lower risks of mortality (HR, 0.93; 95% CI, 0.88-1.00), respectively. LIMITATIONS: Single-center study. CONCLUSIONS: We showed that the SF-36 Physical Composite Score and Physical Functioning and General Health Perception KDQoL-SF domain scores are associated independently with increased risk of mortality in kidney transplant patients. Regular assessment of HRQoL may be a useful tool to inform health care providers about the prognosis of kidney transplant recipients. Additional studies are needed to assess whether interventions aimed at improving HRQoL would improve clinical outcomes in this patient population.

Sleep disorders, depressive symptoms and health-related quality of life--a cross-sectional comparison between kidney transplant recipients and waitlisted patients on maintenance dialysis.

BACKGROUND: Kidney transplantation is believed to improve health-related quality of life (HRQoL) of patients requiring renal replacement therapy (RRT). Recent studies suggested that the observed difference in HRQoL between kidney transplant recipients (Tx) vs patients treated with dialysis may reflect differences in patient characteristics. We tested if Tx patients have better HRQoL compared to waitlisted (WL) patients treated with dialysis after extensive adjustment for covariables. METHODS: Eight hundred and eighty-eight prevalent Tx patients followed at a single outpatient transplant clinic and 187 WL patients treated with maintenance dialysis in nine dialysis centres were enrolled in this observational cross-sectional study. Data about socio-demographic and clinical parameters, self-reported depressive symptoms and the most frequent sleep disorders assessed by self-reported questionnaires were collected at enrollment. HRQoL was assessed by the Kidney Disease Quality of Life Questionnaire. RESULTS: Patient characteristics were similar in the Tx vs WL groups: the proportion of males (58 vs 60%), mean ± SD age (49 ± 13 vs 49 ± 12) and proportion of diabetics (17 vs 18%), respectively, were all similar. Tx patients had significantly better HRQoL scores compared to the WL group both in generic (Physical function, General health perceptions, Energy/fatigue, Emotional well-being) and in kidney disease-specific domains (Symptoms/problems, Effect- and Burden of kidney disease and Sleep). In multivariate regression models adjusting for clinical and socio-demographic characteristics, sleep disorders and depressive symptoms, the modality of RRT (WL vs Tx) remained independently associated with three (General health perceptions, Effect- and Burden of kidney disease) out of the eight HRQoL dimensions analysed. CONCLUSIONS: Kidney Tx recipients have significantly better HRQoL compared to WL dialysis patients in some, but not all, dimensions of quality of life after accounting for differences in patient characteristics. Utilizing multidimensional disease-specific questionnaires will allow better understanding of treatment, disease and patient-related factors potentially affecting quality of life in patients with chronic medical conditions.