The objective of this study was to compare the HRQOL of pediatric LT recipients to children with other chronic health conditions that share some similar characteristics to LT recipients. Examples of shared characteristics include a history of surgical intervention, the need to take daily medications and the history of having had a life threatening illness. This comparison begins to define how the health state of the LT recipient fits within the spectrum of more common and thus familiar chronic health conditions. Defining HRQOL within this context will help clinicians to better understand the burden of chronic illness for the pediatric LT recipient.
We found pediatric LT patients evidenced significantly better physical health than children with JRA from the perspective of both patients and parents. This was not unexpected, since few LT recipients report pain or physical disabilities, the hallmark symptoms of JRA. Also as expected, parents and patients agreed that HRQOL across all domains was similar for liver and renal transplant recipients and that most aspects of health of the LT recipients were better than that of children on renal dialysis.
Of interest, both LT patients and their parents reported their level of school functioning was lower than children with JRA and diabetes, but similar to other chronic illnesses including patients on dialysis. As noted above, when we compared HRQOL of this cohort to an age, gender and ethnicity matched sample of healthy children, the LT patients and parents reported significantly lower functioning across all domains with the largest effect sizes being in the PedsQL™
School Functioning Scale (8
). This finding is consistent with recent data from a longitudinal study of 823 pediatric LT patients from the SPLIT research consortium which reported 34% of patients were receiving special educational services in school and 20% had repeated a grade, with older participants more likely to have been held back; missing more than 10 days of school per year was reported by one-third of the LT sample (31
). In the current LT sample, questions related to missing days of school had the largest impact on the PedsQL™
School Functioning Scale Score. Since this aspect of HRQOL appears to be a significant issue for patients within all of the six disease categories we studied, treatment strategies that minimize school absences and resources that support academic progress, despite absences, would likely improve HRQOL for children with a wide array of chronic illnesses.
Parents and children in the LT sample and the other chronic disease samples did not always agree on the level of HRQOL experienced by the child. For the most part, parents reported outcomes that were slightly lower than what patients reported for themselves, consistent with findings from other pediatric chronic conditions (3
). The notable exception was the cardiac disease group. The low agreement between the mean subscale values for the child self-report and parent proxy-report for the cardiac sample may in part be attributed to the fact that the parent proxy-report sample (n = 222) included 65 parents of children who did not provide self-report (23
). Nonetheless, these parent-child discrepancies are consistent with both the adult and pediatric literature suggesting information provided by proxy-respondents is not equivalent to reports by the patient (32
). For the LT sample, the intraclass correlations (ICCs) for all sub-scales were in the moderate range, suggesting that parents’ perceptions were reasonably aligned with their children. Yet, it may be difficult for parents to assess their children’s function in domains with less observable or more internal symptoms, such as pain, fatigue and emotional distress. Parents may however, be more aware of age-appropriate functional expectations and better able to assess when their children are struggling as compared to their peers. These observed differences demonstrate the need to evaluate both children’s and parents’ perspectives regarding HRQOL in clinical practice and clinical trials since their different perspectives potentially provide unique information.
Across all domains but emotional functioning, pediatric LT recipients self-reported significantly lower HRQOL than children with type 1 diabetes. This finding stands in contrast to Taylor et al. (2009) who compared the HRQOL of 55 adolescent LT recipients to young people with asthma and diabetes and found that LT recipients scored similarly to these chronic illness groups (17
). Similar to pediatric LT patients, children with type 1 diabetes and their families are required to perform a number of daily self-management behaviors, such as regular blood glucose monitoring, multiple insulin doses, regulation of carbohydrate intake, and frequent exercise (34
). There are well organized support programs for children with type 1 diabetes that promote clinical management and adherence. In fact, a number of behavioral interventions have been developed for children with type 1 diabetes that have shown improvements in treatment adherence (35
), coping skills (36
), and parent-child communication (38
). Given the importance of self-management in both of these populations, and our findings that pediatric LT recipients in the present study self-reported significantly lower HRQOL than children with type 1 diabetes across multiple domains, it may be useful for future research to investigate how components of behavioral interventions developed for children with type 1 diabetes can be extended to the care of pediatric LT patients.
In the present study, pediatric LT patients reported comparable HRQOL to children who had undergone renal transplantation from the perspective of both patients and parents. These data, combined with findings from a separate study in which pediatric LT patients from the present sample evidenced significantly lower generic HRQOL than a matched healthy sample (8
), suggest that the HRQOL of pediatric LT patients is more similar to a child with a chronic health condition than a healthy child. Given these findings, it is recommended that the measurement of HRQOL in pediatric LT patients should be considered for routine assessment in clinical practice as this would aid clinicians in addressing both the physical and psychosocial problems that accompany liver transplantation.
There are a number of limitations to the present study. First, the non-response rates across the chronic disease comparison samples are not known, which may limit the generalizability of our findings. For the LT sample, race/ethnicity was the only measurable difference found in our sample compared to the non-participants (8
). Specifically, non-participants were more likely to be Hispanic. Although the PedsQL™
is available in Spanish, some data collection centers did not have Spanish speaking staff available for recruiting patients. However, it should be noted the percentage of Hispanic patients in this sample was similar to that of pediatric liver recipients listed in the United Network for Organ Sharing (UNOS) registry for the calendar year of 2006, 15% versus 21%, respectively (www.unos.org
). Given that the chronic disease samples came from an existing database, some of the samples were small which may have impacted our ability to detect statistically significant group differences. It should be noted, however, that we presented effect sizes for each comparison and effect sizes are relatively independent of sample size. Working from an existing database, we were not able to match the chronic disease samples to the pediatric LT sample on demographic characteristics; within each chronic disease group, it is also likely that there were patients with varying disease severities that would be expected to impact HRQOL. Finally, we did not have data on time since transplant for the renal transplant sample.
In conclusion, pediatric LT patients manifested impaired HRQOL similar to children with chronic diseases and were more significantly impaired across a number of dimensions for several conditions. These data suggest pediatric LT patients are facing ongoing daily challenges that warrant continuous monitoring and indicate the need for innovative interventions to improve the HRQOL of these patients.