POS1076 ACCELEROMETRY-BASED ASSESSMENT OF BALANCE ALTERATIONS IN DUAL-TASK CONDITIONS IN PATIENTS WITH FIBROMYALGIA – A PILOT CROSS-SECTIONAL STUDY
Authors: Z. Veličković, M. Novičić, N. Šuljagić, I. Soldatovic, M. Janković, G. Radunovic
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Fibromyalgia (FM) is characterized by cognitive decline driven by other symptoms such as pain, fatigue, and depression. Furthermore, balance alterations have been well documented and have an enormous negative effect on patients' performance, increasing their risk of falling; therefore, they must be diagnosed early, accurately, and reliably in terms of prevention and rehabilitation. Regarding activities of daily living, the dual task paradigm is a surrogate for everyday functioning, providing insights into how motor and cognitive functions interact. Wearable sensor devices, such as accelerometers, are devices that can be used to collect data while performing various tasks. There is a lack of data about their usage among FM patients in this context, despite their benefits such as small size and wirelessness, lower cost, portability, and use in both home and real-world settings. <h3>Objectives:</h3> To evaluate the ability of an accelerometry-based method for detecting static and dynamic balance alterations in dual-task settings in FM patients. <h3>Methods:</h3> The 29 non-treated primary fibromyalgia (FM) patients (3 M, 26 F, 48,8±7.75 y) and 31 healthy age and gender-matched subjects (HC) were recruited for this cross-sectional study. All participants were wearing two tri-axial accelerometers: one over the L4-L5 junction (spine) and the other over the right anterior superior iliac spine (hip). Patients' static balance characteristics were assessed using a modified Romberg test across four conditions (open/closed eyes and cognitive task added). All participants completed dynamic balance assessments during walking: one baseline walk (down a 20-metre walkway and return to the starting line), with motor (walking with a glass of water), mental (serial subtraction from number 100), or combined task. Raw data was sent through the Wi-Fi connection from accelerometers to the tablet and then to the central server for further analysis. After signal processing, the feature for discrimination was the summed magnitude area (SMA) of movement which was calculated as: where N represents total number of samples in the data, and <i>a</i><sub><i>x</i></sub>, <i>a</i><sub><i>y</i></sub> and <i>a</i><sub><i>z</i></sub> are three accelerometer axes. <h3>Results:</h3> 31% of the patients (9/29) reported only FM, while 45% (13/29) had low mineral density, osteoporosis or osteopenia as a co-morbidity. As seen in Figure 1, FM patients' SMA values are greater than those of HC, with the difference being more apparent as the task becomes more difficult, implying that static balance changes are more impaired in dual-task situations, particularly with eyes closed. This may also be verified by evaluating the deviation of the SMA parameter, which is larger in FM patients, showing significant heterogeneity. Regarding gait and dinamic balance analysis (Figure 2), there was a significant difference between the two groups in every condition, but the dual-task setting did not show a higher deterioration of balance comparing to baseline gait. <h3>Conclusion:</h3> Balance coordination is more likely to deteriorate in dual-task situations during static compared to dynamic assessment, and a possible explanation is that postural control is compensated by the visual system. It is worth noting that proprioception might be affected by altered sensory input processing commonly seen in FM patients, thus leading us to investigate this further. Wearable sensors and the accelerometry method can potentially be used to evaluate rehabilitation protocols for balance improvement and reducing the frequency of falls and possible fractures. FM patients in our study were not treated, and further research should evaluate the influence of antiepileptics and antidepressants on cognitive status, coordination control, and risk of falling since both groups of drugs have well-known adverse effects on cognition and motoric abilities. <h3>REFERENCES:</h3> <b>NIL.</b> <h3>Acknowledgements:</h3> This work was supported by a voucher (#Q322RSV45) from the European Alliance of Associations for Rheumatology (EULAR). The content is solely the responsibility of the authors and does not necessarily represent the official views of EULAR. <h3>Disclosure of Interests:</h3> <b>None declared.</b>