Abstract
Background: Children with cancer experience decreased quality
of life. The National Institutes of Health has recommended examination
of quality of life factors to promote development of clinical
interventions to reduce suffering. Measuring quality of life in children
based on self-report instruments is limited by subjectivity, age, and
developmental stage. Assessment of posture is a pioneering objective
physical measure that may augment quality of life preceptions among
individuals with cancer.
Procedure: This systematic literature review synthesized
published evidence regarding the relationship between posture and
quality of life. A systematic search using PRISMA guidelines identified
articles describing studies of human subjects that included the
variables of a) posture measured by the standard thoracic kyphosis
angle; and b) quality of life or depression/mood. A total of 14 eligible
studies met inclusion criteria (published 2000-2018). Studies were
graded for level of evidence and themes were identified.
Results: No studies were found in children with cancer. The
majority of the studies (8 of 14) were rated at the moderate level. Key
review findings include evidence supporting: 1) a consistent
bidirectional relationship between posture and quality of life; 2) that
when posture improves, quality of life also increases; and when
depression decreases, posture improves; and 3) emotion is expressed
through posture.
Conclusion: If posture is a sensitive and precise measure of
quality of life, it could strengthen existing measurements and give a
more complete picture to in turn identify children who may benefit from
supportive care interventions during cancer treatment.
One critical aspect of care for children with cancer is assessment of
symptoms and quality of life (QOL) related to both the disease and side
effects of aggressive therapies.1-3 Historically, QOL
research instruments have been based on self-report responses. An
objective physical measure could reduce the time and possible distress
associated with questionnaires, yet changes in conventional circulating
(plasma) biomarkers are confounded by both cancer treatments and disease
progression. Therefore, we proposed investigation of posture as a
promising physical sign of QOL in children with cancer, measured as
thoracic kyphosis. Posture has been studied as a neurologic outcome
measure in survivors of childhood leukemia and brain
tumors,4-6 but not as a QOL outcome for children in
active treatment for cancer. This systematic review investigates the
concept of physical posture as a supplemental measure of QOL that could
be used by pediatric oncology practitioners.
Darwin theorized that humans and animals express emotions in their body
positions (e.g., abnormal spinal curvatures).7Assessing the presence of a Cobb angle on the spine is recognized as the
gold-standard measurement of thoracic kyphosis.8Thoracic kyphosis can also be measured with a manual inclinometer
(Figure 1).9
Precedence for a physical sign to augment subjective reports exists with
concepts such as a) step counts and walk tests for physical activity, b)
restlessness for pain, and c) breathlessness, respiratory rate, or
facial expression for dyspnea. For example, the ability to understand
breathing distress through physical expressions at end of life when the
person can no longer communicate has been studied and
documented.10,11 Adding physical posture to QOL
measures could give a more complete picture of a person’s state in a
similar manner. Before we proceed with more testing, a broad approach
with a systematic review was thought to be warranted because causality
or direction of the variables is not yet known (whether posture impacts
QOL or vice versa).
Based on clinical observation by our dance/movement therapist of
children receiving cancer treatment, we examined posture as an
exploratory QOL outcome measure. Evaluation of the impact of a creative
arts therapy intervention among 100 children with cancer showed evidence
of cross-sectional and longitudinal relationships between posture and
QOL questionnaire scores. At baseline, posture was moderately correlated
with QOL (β = 0.33, p < .05).12 Over
time, posture and QOL improved along the same trajectory (p <
.05 for time*group interaction).13 These statistically
significant results led us to investigate the literature to
theoretically support this finding.
Examination of the relationship between posture and QOL in children with
cancer may provide a novel, objective, non-invasive, and inexpensive
measure of QOL. With further study, posture could be shown to be a
useful measure as a predictive physical sign of QOL, or perhaps for
surveillance of QOL during cancer treatments.14Establishing proof of concept in adults or other populations is often
required prior to exploration in a high risk pediatric population such
as children with cancer. Therefore, the purpose of this systematic
review is to provide an evaluation of existing evidence regarding the
relationship between posture and QOL published in the medical literature
in all populations to lay the foundation to support investigation of
this relationship among children with cancer.