The intersection of pain, fatigue, and cardiovascular risk in teens with juvenile arthritis : a biobehavioral case-control pilot study
Teens with juvenile idiopathic arthritis (JIA) live with chronic pain and fatigue. They are at higher risk of cardiovascular morbidity and mortality than the general population. Yet there is little evidence about the metabolic processes underlying the symptoms and comorbidity. The purpose of this biobehavioral, cross-sectional pilot study is to describe the characteristics of, differences between, and relationships among groups of teens with JIA and healthy controls. The study design is guided by a synthesized model of: metabolomics theory, the Revised Child- and Family Self-Management Framework, and the Symptom Science Model. A group of n=20 controls and n=20 teens with JIA were recruited from a clinic in Austin, TX between August 2018-January 2019. Participants and their parent proxy completed a study visit with a morning, fasting blood sample collection, biometrics, and surveys. Measures include complex symptoms (pain, pain interference, fatigue), phenotypic characterization (individual characteristics, facilitators and barriers, and behaviors), and biomarkers (metabolomics signature and cardiovascular risk factors). Data were analyzed using descriptive statistics, t-tests, chi square, and Pearson’s correlations. Blood samples were processed using mass spectroscopy. Best practices for recruitment strategies for this population and study design were identified. Results indicate that the groups were equivalent in characteristics, yet they share similarities and exhibit important differences between groups. A pattern of metabolites was identified. Additional differences were found between teens with JIA in active versus inactive disease at the time of the study visit. Sixty-five metabolites were identified, 55 of which were common to both groups. Alpha-D-glucose, alpha-ketoglutaric acid, citrate, citrulline, lactate, L-histidine, L-phenylalanine, L-proline, L-serine, L-tyrosine, malate, myristic acid, N-acetyl-D-L-serine, N-acetyl-L-aspartic acid, and uracil were significantly lower in the JIA group relative to controls; Glycine and L-cysteine were significantly higher. Findings from this biobehavioral pilot study indicate 17 metabolites that were significantly different in teens with JIA relative to controls. The pathways in which these metabolites are implicated may be a source of new treatment and prevention options. Results provide initial evidence of symptom clusters or potential biomarkers. Further research is warranted to confirm these findings in a larger sample.