Abstract:
BACKGROUND: Studying patients with chronic fatigue syndrome (CFS), we have developed a method that uses a head-up tilt test (HUTT) to estimate BP and HR instability during tilt, expressed as a ‘haemodynamic instability score’ (HIS).
AIM: To assess HIS sensitivity and specificity in the diagnosis of CFS.
DESIGN: Prospective controlled study.
METHODS: Patients with CFS (n=40), non-CFS chronic fatigue (n=73), fibromyalgia (n=41), neurally mediated syncope (n=58), generalized anxiety disorder (n=28), familial Mediterranean fever (n=50), arterial hypertension (n=28), and healthy subjects (n=59) were evaluated with a standardized head-up tilt test (HUTT). The HIS was calculated from blood pressure (BP) and heart rate (HR) changes during the HUTT.
RESULTS: The tilt was prematurely terminated in 22% of CFS patients when postural symptoms occurred and the HIS could not be calculated. In the remainder, the median(IQR) HIS values were: CFS +2.14(4.67), non-CFS fatigue -3.98(5.35), fibromyalgia -2.81(2.62), syncope -3.7(4.36), generalized anxiety disorder -0.21(6.05), healthy controls -2.66(3.14), FMF -5.09(6.41), hypertensives -5.35(2.74) (p<0.0001 vs. CFS in all groups, except for anxiety disorder, p=NS). The sensitivity for CFS at HIS >-0.98 cut-off was 90.3% and the overall specificity was 84.5%.
DISCUSSION: There is a particular dysautonomia in CFS that differs from dysautonomia in other disorders, characterized by HIS >-0.98. The HIS can reinforce the clinician’s diagnosis by providing objective criteria for the assessment of CFS, which until now, could only be subjectively inferred.
Comment in:
The head-up tilt test for diagnosing chronic fatigue syndrome. [QJM. 2003]
Assessing chronic fatigue. [QJM. 2003]
Source: Naschitz JE, Rosner I, Rozenbaum M, Naschitz S, Musafia-Priselac R, Shaviv N, Fields M, Isseroff H, Zuckerman E, Yeshurun D, Sabo E. The head-up tilt test with haemodynamic instability score in diagnosing chronic fatigue syndrome. QJM. 2003 Feb;96(2):133-42. http://qjmed.oxfordjournals.org/content/96/2/133.long (Full article)