Academic Journal
Time-dependent complexity characterisation of activity patterns in patients with Chronic Fatigue Syndrome.
| Title: | Time-dependent complexity characterisation of activity patterns in patients with Chronic Fatigue Syndrome. |
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| Authors: | Rabaey, Paloma1 (AUTHOR) paloma.rabaey@ugent.be, Decat, Peter2 (AUTHOR), Heytens, Stefan2 (AUTHOR), Vogelaers, Dirk3,4 (AUTHOR), Mariman, An3 (AUTHOR), Demeester, Thomas1 (AUTHOR) |
| Source: | BioPsychoSocial Medicine. 4/2/2024, Vol. 18 Issue 1, p1-21. 21p. |
| Abstract: | Background: Chronic Fatigue Syndrome patients suffer from symptoms that cannot be explained by a single underlying biological cause. It is sometimes claimed that these symptoms are a manifestation of a disrupted autonomic nervous system. Prior works studying this claim from the complex adaptive systems perspective, have observed a lower average complexity of physical activity patterns in chronic fatigue syndrome patients compared to healthy controls. To further study the robustness of such methods, we investigate the within-patient changes in complexity of activity over time. Furthermore, we explore how these changes might be related to changes in patient functioning. Methods: We propose an extension of the allometric aggregation method, which characterises the complexity of a physiological signal by quantifying the evolution of its fractal dimension. We use it to investigate the temporal variations in within-patient complexity. To this end, physical activity patterns of 7 patients diagnosed with chronic fatigue syndrome were recorded over a period of 3 weeks. These recordings are accompanied by physicians' judgements in terms of the patients' weekly functioning. Results: We report significant within-patient variations in complexity over time. The obtained metrics are shown to depend on the range of timescales for which these are evaluated. We were unable to establish a consistent link between complexity and functioning on a week-by-week basis for the majority of the patients. Conclusions: The considerable within-patient variations of the fractal dimension across scales and time force us to question the utility of previous studies that characterise long-term activity signals using a single static complexity metric. The complexity of a Chronic Fatigue Syndrome patient's physical activity signal does not suffice to characterise their high-level functioning over time and has limited potential as an objective monitoring metric by itself. [ABSTRACT FROM AUTHOR] |
| Subject Terms: | *CHRONIC fatigue syndrome, *AUTONOMIC nervous system, *FRACTAL dimensions, *TIME complexity, *PHYSICAL activity |
| ISSN: | 17510759 |
| DOI: | 10.1186/s13030-024-00305-9 |
| Database: | Academic Search Index |