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.