Resumen de Anxiety and joint hypermobility: connecting mind and body
Anxiety disorders are currently considered the most prevalent psychiatric illness across all ages and cause significant disability, which represent a burden to society. The nosology of anxiety disorders has changed significantly during the past centuries. While old concepts like neurosis embraced organic models of anxiety, in which symptoms of anxiety were interpreted in the context of medical illnesses, new nosological classification has moved towards the psychological, cognitive and behavioral aspects of anxiety. However, some studies reported the greatest proportion of the cost of anxiety is attributed to lost or reduced productivity, and the direct costs of medical treatment due to the unexplained physical or somatic symptoms. New models of somatic comorbidity among anxiety disorders have emerged over the past years and in this project, we focus on the relationship between the Joint Hypermobility Syndrome (also known as Ehlers Danlos-Hypermobile type (JHS/hEDS)) and Anxiety disorders, which was described for the first time over 30 years ago. We aimed to further study this association along with the underlying mechanisms with the ultimate goal of understanding the different dimensions of the psychopathology associated with JHS/hEDS.
A literature reviews confirm an increasing amount of evidence pointing towards a high prevalence of psychiatric conditions among individuals with JHS/hEDS. Particularly, JHS/hEDS is strongly associated with anxiety and there is also limited but growing evidence that JHS/hEDS is also associated with depression, eating and neuro-developmental disorders as well as alcohol and tobacco misuse. In the area of anxiety disorders, clinical and nonclinical studies confirm the solid association between JHS and anxiety. Specifically, JHS has been found to be associated with higher frequency of the so-called endogenous anxiety disorders (panic disorders and agoraphobia) along with higher intensity of anxiety and fears and greater physical and somatic complaints. In one of the studies included in this thesis, we have proven that this association is also maintained in elderly populations.
The underlying mechanisms behind this association include genetic risks, increased exteroceptive and interoceptive mechanisms and decreased proprioception. Recent neuroimaging studies have also shown an increase response in emotion processing brain areas which could explain the high affective reactivity seen in JHS/hEDS. In this thesis, we have also studied the autonomic nervous functioning in these patients and found that they have an atypical regulation of the ANS and are more likely to suffer from autonomic-related illnesses. These findings are in line with other studies that have shown that patients with JHS/hEDS are more likely to suffer from stress-related illnesses such as fibromyalgia or irritable bowel syndrome.
As part of this thesis, we developed a new model of somatic illness called the “Neuroconnective phenotype” in which the core includes the relationship between anxiety and joint hypermobility and the different somatic, psychological, cognitive and behavioral aspects are described. This phenotype should be implemented to ensure proper assessment and to guide for more specific treatments. Future lines of research should further explore the biological basis of this association and expand and develop the therapeutic dimension.
