Discussion
These findings confirm our hypothesis that age differences exist in QOL.
Older children reported worse quality of life, which is clinically seen
with adolescents tolerating cancer treatment worse than toddlers. Our
findings contrast with two studies, one in children with
leukemia,2 and in children with advanced
cancer,6 in which younger children had worse reported
QOL. In the study of children with leukemia, perhaps this difference was
related to a younger age range in the study, or because leukemia is more
common in young children, whereas our study examined children with all
cancer diagnoses. Compared to the findings in the study of children with
advanced cancer, our study’s findings may reflect higher symptom burden
in adolescents in the first year of chemotherapy due to treatment
toxicity.
Older children also had less erect posture, which is confirmed by the
literature and fits with clinical observations that young children sit
and stand straighter than adolescents. However, our hypothesis that sex
differences exist in posture was not confirmed and differs from
published literature. Further study is warranted to explore whether sex
differences truly exist in posture.
Pain and nausea are the most prevalent distressing symptoms reported by
children with cancer.5,44 We also found that age had a
moderate relationship with pain and nausea and therefore both should be
targeted for symptom management especially in older children. Potential
strategies that may appeal to adolescents include integrative modalities
that have been shown to improve both pain and nausea in children with
cancer.45,46
In our study, worry had the strongest relationship with age. This
suggests the need for improved treatment to address anxiety through
medication management and cognitive behavioral
interventions,47 particularly for older children.
Integrative modalities such as aromatherapy or acupuncture also are
known to have usefulness in children with cancer and may be better
tolerated in adolescents.48
We did not find any other demographic associations with QOL, posture, or
Faces Scale scores, which diverged from our hypotheses and from the
literature. Other studies have found that girls report worse QOL, but
our results showed no differences between girls and boys on either the
subjective or the objective QOL measures. Although disparities for
minorities have also been reported in QOL for children with cancer, we
did not find any differences based on race or ethnicity. However, we
collapsed the racial and ethnic subsets into a single dichotomous
“minority status” variable due to sample size limitations, a data
analysis strategy that could mask results for specific races if these
exist.
We found moderately strong relationships between posture, PedsQL, and
the Faces Scale, which confirm the idea that all three of these metrics
are related to a single underlying construct, QOL. These findings
suggest that children who report that they feel better, also stand up
straighter, and pick a happier face on the scale. Posture was
particularly related to the more physical aspects of the PedsQL such as
pain and nausea, which is consistent with the theory of embodiment in
which the body stature reflects symptoms and
emotions.49 Children’s report of pain had the
strongest relationship with the Faces Scale, which aligns with the
original intent of the Faces Scale for pain
assessment.26 However, the total PedsQL scores for
both child and parent report also had moderate relationships with the
Faces Scale, a finding that supports further study of this simple tool
as a way to measure global QOL in children with cancer.
Likewise, posture and the Faces Scale were moderately related and thus
both measures show promise as simple methods to reflect the overall
sense of how a child with cancer is feeling. If these relationships can
be confirmed and shown to be responsive to change over time, posture and
the simplified Faces Scale could potentially be used as surrogates for
the more time-consuming QOL questionnaires. Furthermore, the Faces Scale
was the only measure that had 100 percent completion which exemplifies
the feasibility of this simplified measure in children under stress
during cancer treatment.
Additionally, the posture measure could represent a biologic and
objective technique that would obviate the subjective limitations of QOL
questionnaires.50,51 Posture measures have the added
benefit of not causing increased pain or distress as seen with blood
draws or obtaining cerebrospinal fluid. A posture assessment is even
less invasive than obtaining a saliva sample, except the child must feel
well enough to stand, which may have been the reason that this measure
had the lowest completion rate in our study (68%). A sitting posture
could also be explored for very sick patients. The posture measure could
also obviate the limitations of other objective systemic biomarkers such
as cortisol that are influenced by the cancer or its treatment.
As a retrospective secondary analysis, this study was powered for the
original aims and no correction was used for inflated alpha. Therefore,
the current results must be viewed with caution. Although the measures
were previously validated and their psychometric characteristics are
generally strong, the subscale for cognition on the PedsQL may warrant
further examination because it was the only subscale that reflected a
significant difference based on sex (parent report) and SES (child
report). Selection bias may have existed because children and their
parents who chose to participate in the study may have been more likely
to do art or were perhaps more interested in QOL. Additionally, the ages
of children in this study were skewed toward younger children.
Replication of the current results with a larger and more diverse sample
of children with cancer is therefore needed.
This study advances the field of symptom science in children with
cancer. By adding to the literature on demographic associations with
QOL, future intervention studies can now target the specific high-risk
group of older children. More in-depth study of the relationship of sex
and age with posture in children with cancer will also further the
investigation of posture as a potential biomarker of QOL. The
correlation of the Faces Scale to the PedsQL also supports further study
of simplified measures of overall QOL in children with cancer. A
prospective multi-site longitudinal study is warranted to further
examine posture as an objective measure of QOL in children with cancer.