Autonomic function in chronic fatigue syndrome with and without painful temporomandibular disorder

Abstract

Background: Chronic fatigue syndrome (CFS) is heterogeneous in nature, yet no clear subclassifications currently exist. There is evidence of dysautonomia in almost 90% of patients and CFS is often co-morbid with conditions associated with autonomic nervous system (ANS) dysfunction, such as temporomandibular disorders (TMD). The present study examined the point prevalence of TMD in a sample of people with CFS and explored whether co-morbidity between the conditions is associated with greater ANS dysfunction than CFS alone. Method: Fifty-one patients and 10 controls underwent screening for TMD. They completed a self-report measure of ANS function (COMPASS-31) and objective assessment of heart rate variability during rest and standing (derived using spectral analysis). Frequency densities in the high-frequency (HF) and low-frequency (LF) band were calculated. Results: Patients with CFS were divided into those who screened positive for TMD (n = 16, 31%; CFS + TMD) and those who did not (n = 35, 69%; CFS − TMD). Both CFS groups had significantly higher self-rated ANS dysfunction than controls. CFS + TMD scored higher than CFS − TMD on the orthostatic and vasomotor subscales. The CFS + TMD group had significantly higher HF and significantly lower LF at rest than the other two groups. In discriminant function analysis, self-report orthostatic intolerance and HF units correctly classified 75% of participants. Conclusions: Almost one-third of CFS patients screened positive for TMD and this was associated with greater evidence of parasympathetic dysfunction. The presence of TMD shows potential as an effective screen for patients with CFS showing an autonomic profile and could help identify subgroups to target for treatment.

Keywords:

• chronic fatigue syndrome
• temporomandibular disorder
• autonomic dysfunction
• dysautonomia
• phenotypes
• heart rate variability
• orthostatic intolerance

Acknowledgements

LR analysed the data and wrote the manuscript. JD contributed to study design, was involved in data analysis & interpretation, and wrote sections of the manuscript pertaining to TMDs. LM was involved in the design of the study and conducted the data collection. JN secured the funding and was instrumental in study design, wrote sections of the manuscript pertaining to methodology, and was involved in data analysis and interpretation. All authors read and approved the final manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Funding

This research was funded by the Medical Research Council [grant number MR/J002712/1] to JN.

Additional information

Notes on contributors

Lucy J. Robinson

Lucy J. Robinson is a Clinical Psychologist and Clinical Academic Fellow at Newcastle University. Her research interests include persistent physical symptoms, interoception and the interaction between life events and physiology in the experience of distressing physical symptoms.

Justin Durham

Justin Durham is a Senior Lecturer and honorary Consultant Oral Surgeon with a specialism in orofacial pain.

Laura L. MacLachlan

Laura L. MacLachlan is a medic who was involved with studies into Chronic Fatigue Syndrome as part of her Doctor of Medicine degree.

Julia L. Newton

Julia L. Newton is Clinical Professor of Aging and Medicine at Newcastle University as well as Dean of Clinical Medicine. She has expertise in Chronic Fatigue Syndrome and autonomic function.