Reduced complexity of activity patterns in patients with Chronic Fatigue Syndrome: a case control study

Chronic fatigue syndrome (CFS) is an illness characterised by pervasive physical and mental fatigue without specific identified pathological changes. Many patients with CFS show reduced physical activity which, though quantifiable, has yielded little information to date.

Nonlinear dynamic analysis of physiological data can be used to measure complexity in terms of dissimilarity within timescales and similarity across timescales. A reduction in these objective measures has been associated with disease and ageing.

We aimed to test the hypothesis that activity patterns of patients with CFS would show reduced complexity compared to healthy controls.

Methods: We analysed continuous activity data over 12 days from 42 patients with CFS and 21 matched healthy controls. We estimated complexity in two ways, measuring dissimilarity within timescales by calculating entropy after a symbolic dynamic transformation of the data and similarity across timescales by calculating the fractal dimension using allometric aggregation.

Results: CFS cases showed reduced complexity compared to controls, as evidenced by reduced dissimilarity within timescales (mean (SD) Renyi(3) entropy 4.05 (0.21) vs.

4.30 (0.09), t=-6.6, p<0.001) and reduced similarity across timescales (fractal dimension 1.19 (0.04) vs. 1.14 (0.04), t = 4.2, p<0.001).

This reduction in complexity persisted after adjustment for total activity.

Conclusions: Patients with CFS show evidence of reduced complexity of activity patterns. Measures of complexity applied to activity have potential value as objective indicators for CFS.

Author: Christopher BurtonHans KnoopNikola PopovicMichael SharpeGijs Bleijenberg
Credits/Source: BioPsychoSocial Medicine 2009, 3:7

Published on: 2009-06-02

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Comments Page 1 of 1

Peter

Posted 1086 days ago

Chronic Fatigue in my experienced is associated with depleted glutathione levels. We all produce less Glutathione from the age of twenty but some people run low earlier. Toxins are sometimes associated with low levels because Glutathione is used up detoxifying the body. Any way taking Glutathione does not help because it is broken down in the digestive process. There are precursors that have been verified and quantified to increase Glutathione levels in our cells and it's wonderful.
Glutathione is essential for cell health and all diseases start at some level of cellular dysfunction.
Any how have a look at what Doctors say.
http://max4me.blogspot.com

Clint

Posted 1087 days ago

Thanks for the study.
From someone formerly living a full, creative life, who has had CFS for nearly 10 years, this translates into the common feeling among sufferers: "I am losing my life."

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