An investigation into the relationship between obesity and pain in the adolescent rheumatology population: An MSc Nursing Project
Background: An extensive literature review concluded that in adults, obesity has been found to be associated with an increase in the symptoms of chronic conditions; in particular the symptoms of chronic musculoskeletal pain syndrome (Kumar et al., 2015) due to excess weight putting additional strain on the joints (Lee, 2013). However this association has not been found to be causal (Okifuji and Hare, 2015) and has yet to be studied in the adolescent rheumatology JIA and CPS populations.
Aims: To investigate whether there are associations between high pain scores, measured using a 0-10cm pain visual analogue scale (PVAS), and body fat measures (fat mass (FM), fat percentage (F%) and body mass index centile (BMI%)), gender, age or disease group (JIA versus CPS) in the adolescent rheumatology population. Additionally to assess whether body fat composition was significantly higher in the non-inflammatory cohort compared with the inflammatory rheumatic disease cohort.
Methods: Anonymised data (collected between August 2015 and May 2016) was extracted from the University College London Hospital (UCLH) adolescent rheumatology clinical database. SPSS was utilised to created models and assess the relationships between PVAS, age, gender, diagnosis and body fat compositions. 187 datasets met the inclusion criteria.
Results: CPS patients were significantly heavier than JIA patients (median fat mass 17.05 vs 14.4 respectively; p 0.007) and reported higher pain scores (6 vs 2 respectively; p <0.05). There were no statically significant correlations between pain scores and body fat measures (weight, fat mass, fat percentage and BMI percentile p>0.05). Contrary to trends observed in the aforementioned studies, this project found no statistically significant correlations between a higher fat mass, fat percentage and BMI percentile and higher pain scores across the multiple linear regression models for: ‘all patients’ (FM r2=0.16, p 0.98; F% r2=0.16, p 0.35; BMI% r2=0.16, p 0.60), ‘JIA’ (FM r2=0.02, p 0.65; F% r2=0.02, p 0.33; BMI% r2=0.02, p 0.51) and ‘CPS’ (FM r2=0.15, p 0.52; F% r2=0.15, p 0.9; BMI% r2=0.02, p 0.51) groups.
Conclusions: In contrast with findings from adult studies, pain in the adolescent CPS population cannot be mainly attributed to obesity. Variations of somatic and psychosocial factors are likely contributors to pain in this group, therefore a holistic approach in managing pain in this population in necessary for clinicians. The results of this study imply body fat measures in adolescents are not necessarily an indicator of wider health, especially as school aged children and teenagers tend to be more active/ less sedentary than adults (Caspersen et al., 2000, Sigmund et al., 2007, Sallis, 2000). The findings of this study may be generalizable to a wider adolescent rheumatology population, as data were obtained from a large London tertiary referral centre.
Recommendation: The results of this project demonstrate that the factors which may cause/ correlate with pain are incredibly complex. As always, it is important to take a holistic and personalised approach when caring, treating and advising patients on how best to manage their condition. The absence of statistical significance found should not be taken as an indication of a lack of clinical significance; as always patients will be advised on adopting a healthy balanced diet and exercise in order to build and maintain muscular strength. These finding have reinforced the necessity of more research into the variables which may influence pain in the adolescent CPS group.
Implementation: These findings will be presented to the wider adolescent rheumatology research and clinical teams at University College London Hospital/ University College London. An abstract based on the findings of this thesis has been accepted to University College London Hospital’s Centre for Nurse and Midwife Led Research conference. In the New Year a poster will be displayed at this event as well as future conferences nationally and internationally, if accepted. Within the next 12 months, a paper will be submitted to the British Journal of Nursing (and/or some equivalent journals) as well as a Letter to Rheumatology.