disequilibrium – American ME and CFS Society

Converging Evidence of Similar Symptomatology of ME/CFS and PASC Indicating Multisystemic Dyshomeostasis

Abstract:

The purpose of this article is to review the evidence of similar symptomatology of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and post-acute sequelae of SARS-CoV-2 infection (PASC).

Reanalysis of data from a study by Jason comparing symptom reports from two groups of ME/CFS and PASC patients shows a notably similar symptomatology. Symptom scores of the PASC group and the ME/CFS group correlated 0.902 (p < 0.0001) across items. The hypothesis is presented that ME/CFS and PASC are caused by a chronic state of multisystemic disequilibrium including endocrinological, immunological, and/or metabolic changes.

The hypothesis holds that a changed set point persistently pushes the organism towards a pathological dysfunctional state which fails to reset. To use an analogy of a thermostat, if the ‘off switch’ of a thermostat intermittently stops working, for periods the house would become warmer and warmer without limit. The hypothesis draws on recent investigations of the Central Homeostasis Network showing multiple interconnections between the autonomic system, central nervous system, and brain stem.

The hypothesis helps to explain the shared symptomatology of ME/CFS and PASC and the unpredictable, intermittent, and fluctuating pattern of symptoms of ME/CFS and PASC. The current theoretical approach remains speculative and requires in-depth investigation before any definite conclusions can be drawn.

Source: Marks DF. Converging Evidence of Similar Symptomatology of ME/CFS and PASC Indicating Multisystemic Dyshomeostasis. Biomedicines. 2023; 11(1):180. https://doi.org/10.3390/biomedicines11010180 https://www.mdpi.com/2227-9059/11/1/180 (Full text)

Paradigm shift to disequilibrium in the genesis of orthostatic intolerance in patients with myalgic encephalomyelitis and chronic fatigue syndrome

Abstract:

Background: Orthostatic intolerance (OI) markedly impairs activities of daily living in patients with myalgic encephalomyelitis (ME) or chronic fatigue syndrome. OI is surmised to be a cardiovascular symptom correlated with cerebral hypo-perfusion and exaggerated sympathetic activation. Postural instability or disequilibrium may be part of the etiology of OI.

Methods: The study comprised 72 patients with ME (18 men, 54 women; mean age, 37 ± 10 years) who underwent neurological examinations and the 10 min standing test. We quantified disequilibrium (instability upon standing with feet together and eyes shut), ability to complete the 10 min standing test, and postural orthostatic tachycardia (POT) during the test.

Results: Disequilibrium was detected in 23/72 (32%) patients and POT in 16 (22%). Nineteen (26%) patients failed to complete the 10 min standing test; disequilibrium was significantly more common in the 19- patient subgroup than in the 53-patient test-completing subgroup (89% vs. 11%, p < 0.01). However, the rate of POT was not different between the groups (21% vs. 23%, p = 1.00). Compared with the 49 (68%) patients without disequilibrium, the 23 (32%) patients with disequilibrium were significantly more likely to have failed to complete the test (74% vs. 4%, p < 0.01). The rate of POT was comparable between the groups (23% vs. 22%, p = 1.00). Among patients with disequilibrium who failed to complete the 10 min standing test and had a previous record, 6/8 had completed the test 6-24 months earlier when all six had reported no disequilibrium.

Conclusion: Disequilibrium should be recognized as an important cause of OI in patients with ME.

Source: Miwa K, Inoue Y. Paradigm shift to disequilibrium in the genesis of orthostatic intolerance in patients with myalgic encephalomyelitis and chronic fatigue syndrome. Int J Cardiol Hypertens. 2020 May 20;5:100032. doi: 10.1016/j.ijchy.2020.100032. PMID: 33447761; PMCID: PMC7803012. https://pubmed.ncbi.nlm.nih.gov/33447761/

The etiologic relation between disequilibrium and orthostatic intolerance in patients with myalgic encephalomyelitis (chronic fatigue syndrome)

Abstract:

BACKGROUND: Orthostatic intolerance (OI) causes a marked reduction in the activities of daily living in patients with myalgic encephalomyelitis (ME) or chronic fatigue syndrome. Most symptoms of OI are thought to be related to cerebral hypo-perfusion and sympathetic activation. Because postural stability is an essential element of orthostatic tolerance, disequilibrium may be involved in the etiology of OI.

METHODS AND RESULTS: The study comprised 44 patients with ME (men, 11 and women, 33; mean age, 37±9 years), who underwent neurological examinations and 10-min standing and sitting tests. Symptoms of OI were detected in 40 (91%) patients and those of sitting intolerance were detected in 30 (68%). Among the 40 patients with OI, disequilibrium with instability on standing with their feet together and eyes shut, was detected in 13 (32.5%) patients and hemodynamic dysfunction during the standing test was detected in 19 (47.5%); both of these were detected in 7 (17.5%) patients. Compared with 31 patients without disequilibrium, 13 (30%) patients with disequilibrium more prevalently reported symptoms during both standing (100% vs. 87%, p=0.43) and sitting (92% vs. 58%, p=0.06) tests. Several (46% vs. 3%, p<0.01) patients failed to complete the 10-min standing test, and some (15% vs. 0%, p=0.15) failed to complete the 10-min sitting test. Among the seven patients with both hemodynamic dysfunction during the standing test and disequilibrium, three (43%) failed to complete the standing test. Among the 6 patients with disequilibrium only, 3 (50%) failed while among the 12 patients with hemodynamic dysfunction only, including 8 patients with postural orthostatic tachycardia, none (0%, p=0.02) failed.

CONCLUSIONS: Patients with ME and disequilibrium reported not only OI but also sitting intolerance. Disequilibrium should be recognized as an important cause of OI and appears to be a more influential cause for OI than postural orthostatic tachycardia in patients with ME.

Source: Miwa K, Inoue Y. The etiologic relation between disequilibrium and orthostatic intolerance in patients with myalgic encephalomyelitis (chronic fatigue syndrome). J Cardiol. 2018 Mar 24. pii: S0914-5087(18)30058-3. doi: 10.1016/j.jjcc.2018.02.010. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/29588088

Vestibular function test anomalies in patients with chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is distinguished by the new onset of debilitating fatigue that lasts at least 6 months, concomitant with other symptoms to be described later. Many CFS patients complain of disequilibrium, yet the exact type of the balance dysfunction and its function and its location (peripheral vs. central) have not been described.

Herein we report results of vestibular function testing performed on 11 CFS patients. These results revealed no predominant pattern of abnormalities. Patients typically performed below average in dynamic posturography testing, with a significant number of falls in the tests requiring subjects to depend heavily on the vestibular system. One patient had abnormal caloric testing, while 3 had abnormally low earth vertical axis rotation (EVA) gains at the higher frequencies tested.

As a group, the average gain of EVA was significantly lower than normals in the 0.1 – 1.0 Hz range (p < 0.05). In earth horizontal axis rotation, the CFS group had a higher than normal bias value for the optokinetic (OKN) and eyes open in the dark conditions (p < 0.05), but had normal scores during visual vestibular reflex testing. Five of the 11 subjects had an abnormal OKN bias build up over the course of the run, equal to or actually exceeding the 60 degrees/s target velocity by as much as 14 degrees/s.

Altogether, these results are more suggestive of central nervous system deficits than of peripheral vestibular disfunction.

Source: Ash-Bernal R, Wall C 3rd, Komaroff AL, Bell D, Oas JG, Payman RN, Fagioli LR. Vestibular function test anomalies in patients with chronic fatigue syndrome. Acta Otolaryngol. 1995 Jan;115(1):9-17. http://www.ncbi.nlm.nih.gov/pubmed/7762393