As autonomic nervous system dysfunction is frequently reported in CFS with orthostatic intolerance (a common symptom that can be objectively assessed), researchers from Newcastle University explored the clinical value of non-invasive optical multi-site photoplethysmography (PPG) technology to assess cardiovascular responses to standing.
A significant reduction in the overall pulse timing response to controlled standing was found for the CFS group. There were no significant differences between subject groups for the AMP measure at any site. Changes in AMP with tilt were, however, weakly significantly and negatively correlated with fatigue severity (p < 0.05). Receiver operating characteristic (ROC) analysis of timing measures produced an area under the curve of 0.81. Experimental linear discriminant classification analysis comparing both timing and amplitude measures produced an overall diagnostic accuracy of 82%.
Pulse wave abnormalities have been observed in CFS and represent a potential objective measure to help differentiate between CFS patients and healthy controls.
