Open AccessEvidence of altered cardiac autonomic regulation in myalgic encephalomyelitis/chronic fatigue syndrome
Author(s) -
Maximillian J. Nelson,
Jasvir S. Bahl,
Jonathan D. Buckley,
Rebecca L. Thomson,
Kade Davison
Publication year - 2019
Publication title -
medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.59
H-Index - 148
eISSN - 1536-5964
pISSN - 0025-7974
DOI - 10.1097/md.0000000000017600
Subject(s) - medicine , chronic fatigue syndrome , heart rate , cardiology , heart rate variability , orthostatic intolerance , anaerobic exercise , tilt table test , encephalomyelitis , physical therapy , blood pressure , central nervous system
Background: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a complex condition with no reliable diagnostic biomarkers. Studies have shown evidence of autonomic dysfunction in patients with ME/CFS, but results have been equivocal. Heart rate (HR) parameters can reflect changes in autonomic function in healthy individuals; however, this has not been thoroughly evaluated in ME/CFS. Methods: A systematic database search for case-control literature was performed. Meta-analysis was performed to determine differences in HR parameters between ME/CFS patients and controls. Results: Sixty-four articles were included in the systematic review. HR parameters assessed in ME/CFS patients and controls were grouped into ten categories: resting HR (RHR), maximal HR (HR max ), HR during submaximal exercise, HR response to head-up tilt testing (HR tilt ), resting HR variability (HRV rest ), HR variability during head-up tilt testing (HRV tilt ), orthostatic HR response (HR OR ), HR during mental task(s) (HR mentaltask ), daily average HR (HR dailyaverage ), and HR recovery (HRR) Meta-analysis revealed RHR (MD ± 95% CI = 4.14 ± 1.38, P < .001), HR tilt (SMD ± 95% CI = 0.92 ± 0.24, P < .001), HR OR (0.50 ± 0.27, P < .001), and the ratio of low frequency power to high frequency power of HRV rest (0.39 ± 0.22, P < .001) were higher in ME/CFS patients compared to controls, while HR max (MD ± 95% CI = –13.81 ± 4.15, P < .001), HR at anaerobic threshold (SMD ± 95% CI = –0.44 ± 0.30, P = 0.005) and the high frequency portion of HRV rest (–0.34 ± 0.22, P = .002) were lower in ME/CFS patients. Conclusions: The differences in HR parameters identified by the meta-analysis indicate that ME/CFS patients have altered autonomic cardiac regulation when compared to healthy controls. These alterations in HR parameters may be symptomatic of the condition.