Central Sensitization and Associated Factors in Adolescents With Joint Hypermobility and Dysautonomia

Abstract

Background: Postural Orthostatic Tachycardia Syndrome (POTS) is a disorder of the autonomic nervous system that has high association with chronic pain syndromes such as fibromyalgia, migraine disorders, and chronic abdominal pain in adolescents with the diagnosis. Many of these disorders are characterized as central sensitization disorders, or pathological pain memory mediated by neural plasticity. Ehlers Danlos Syndrome Type 3 (EDS-3), also called joint hypermobility syndrome (JHS) is a genetic disorder of the connective tissue that causes joint laxity and is also highly associated with chronic pain syndromes as well as POTS. Methods: This study proposed to characterize POTS as a disorder of central sensitization. The hypothesis, presented within the proposed theoretical model, demonstrates that JHS leads to chronic pain that results in central sensitization and autonomic nervous system dysfunction (POTS). Other factors that were evaluated were anxiety and function. A sample size of 40 adolescents between the ages of 12 and 19 years were recruited from the cardiology and pain clinics at Children’s National Medical Center. Analysis of data utilizing Wilcoxon, Chi square, Pearson correlation, and logistic regression tests were completed using SAS 9.3. Results: In comparison to those without POTS, there were no significant associations found between having the diagnosis of POTS and any other variable studied in the model. JHS had a stronger correlation with anxiety, central sensitization, both subjectively, and objectively with hyperalgesia on Aδ sensory nerve fiber when compared to those without JHS. Subjective central sensitization was highly correlated with anxiety, function, age, and female gender. Function and central sensitization had a significant association even when removing anxiety as a covariate. Conclusions: These findings suggest that joint hypermobility may be a factor that contributes to the development of central sensitization in individuals with chronic pain. Dysautonomia is likely not a disorder of central sensitization, but rather a variable related to joint hypermobility and chronic pain in ways yet to be discovered. As previously discussed in other literature, anxiety has strong associations with central sensitization and functional disability in chronic pain syndromes, and when treated effectively may increase function in those that suffer with these disorders.