Author(s): BEHAVA, M., RUFFINO, C.1, LE PINSEC, F.1, LUSIANNA, T.2,3, GINDRE, C.2,3, GROSPRÊTRE, S.1,4, Institution: UNIVERSITÉ MARIE ET LOUIS PASTEUR , Country: FRANCE, Abstract-ID: 2325

INTRODUCTION:
Generalized joint hypermobility (GJH), whether congenital or acquired, refers to an excessive range of motion in the joints, with or without symptoms. It affects 10-30% of the population [1], predominantly women and children, and decreases with age [2]. When GJH is a part of a connective tissue disorders (e.g. Ehlers Danlos Syndrome), or is associated with symptoms (e.g. chronic pain, micro-/macro-traumas or muscle weakness), alterations in several functional domains, including cognitive functions, have been reported [3]. However, the relationship between the degree of joint hypermobility, considered along a continuum, and specific cognitive capacities remains poorly understood. Thus, the aim of this study was to investigate the potential links between hypermobility severity and cognitive functions, including attention, memory, cognitive flexibility and inhibition.
METHODS:
18 healthy young adults (7 women, age: 24.4 ± 5.0 years, height: 172.1 ± 9.4 cm, weight: 72.3 ±15.5 kg) participated in this study. The degree of hypermobility was assessed with the Beighton score [4], a standardized battery of joint mobility tests ranging from 0 to 9, with higher scores indicating greater hypermobility (≥5 defining the threshold for GJH). Cognitive capacities were quantified through four cognitive tests, performed in a randomized order: Go/NoGo (inhibition) test, Working Memory Capacity (WMC) test, Trail Making Test (TMT, cognitive flexibility), and Letter Cancellation Test (LCT, selective visuospatial attention).
RESULTS:
Preliminary results (Spearman correlations) did not reveal any significant relationship between hypermobility score and performance (reaction time and errors) in Go/NoGo and TMT (r = -0.011, p = 0.969, r = 0.128, 0.636 and r = -0.110, p = 0.664 respectively). Interestingly, a negative moderate correlation was observed between hypermobility and performance in the LCT score (r = -0.424, p = 0.079), whereas a positive moderate correlation was found between hypermobility and performance in WMC task (r = 0.414, p = 0.098).
CONCLUSION:
These correlations, although moderate, indicate a potential link between hypermobility and cognitive functions. The degree of hypermobility does not seem to generally alter the cognitive functions in the same direction, but rather generates a specific cognitive profile. Indeed, hypermobility may be associated with poorer selective visuospatial attention and better working memory. Ongoing recruitment and the inclusion of additional participants will help confirm and refine these results. Given the current limited sample, investigating how hypermobility affects cognitive functions may help inform tailored interventions and training strategies for individuals with GJH.

[1] A. Hakim and R. Grahame, Best Pract. Res. Clin. Rheumatol., 2003.
[2] A. Sobhani-Eraghi, and al. J. Res. Med. Sci., 2020.
[3] C. Baeza-Velasco and al. Rheumatol. Int., 2017.
[4] P. Beighton and al., Ann. Rheum. Dis., 1973.