The effects of warm water immersion on blood pressure, heart rate and heart rate variability in people with chronic fatigue syndrome.

Abstract

BackgroundChronic fatigue syndrome (CFS) is a central sensitisation syndrome with abnormalities in autonomic regulation of blood pressure (BP), heart rate (HR) and heart rate variability (HRV). Prior to exploring the effects of hydrotherapy as a treatment for this population, changes in BP, HR and HRV during warm water immersion need to be established.ObjectivesThe study aimed to determine the effects of warm water immersion on BP, HR and HRV in adults with CFS compared to matched-pair healthy adults.MethodA quasi-experimental, single-blinded study design was used with nine CFS participants and nine matched controls. Participants’ BP, HR and HRV were measured before, after 5 minutes and post warm water immersion at the depth of the fourth intercostal space, using the Ithlete® System and Dräger BP monitor.ResultsThere was a significant difference between groups in HRV prior to immersion (control group: 73 [55–74] vs. chronic fatigue syndrome group: 63 [50–70]; p = 0.04). There was no difference in HRV post-immersion. A significant difference in HR after immersion was recorded with the control group having a lower HR than those with CFS (78 [60–86] vs. 86 [65–112]; p = 0.03). The low HRV present in the CFS group prior to immersion suggests autonomic dysregulation. Individuals with CFS may have reduced vagal nerve activation post-immersion. During immersion, HRV of the CFS participants improved similar to that of the healthy controls.ConclusionPrior to immersion, differences were present in the HRV of the participants with CFS compared to healthy controls. These differences were no longer present post-immersion.Clinical implicationsWarm water immersion appears safe and may be beneficial in the management of individuals with CFS.