Hemodynamic instability in chronic fatigue syndrome: Indices and diagnostic significance

• Published in: Seminars in arthritis and rheumatism Vol. 31; no. 3; pp. 199 - 208
• Main Authors: Naschitz, Jochanan E., Sabo, Edmond, Naschitz, Shaul, Shaviv, Naomi, Rosner, Itzhak, Rozenbaum, Michael, Gaitini, Luis, Ahdoot, Allen, Ahdoot, Michael, Priselac, Renata Musafia, Eldar, Samuel, Zukerman, Eli, Yeshurun, Daniel
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA Elsevier Inc 01-12-2001; Elsevier
• Subjects: Adult; Anxiety Disorders - diagnosis; Anxiety Disorders - physiopathology; Biological and medical sciences; Blood Pressure - physiology; Chronic fatigue syndrome; Diagnosis, Differential; Diseases of the osteoarticular system; Fatigue Syndrome, Chronic - diagnosis; Fatigue Syndrome, Chronic - physiopathology; Female; Fibromyalgia - diagnosis; Fibromyalgia - physiopathology; fractal analysis; Fractals; Heart Rate - physiology; Humans; Hypertension - diagnosis; Hypertension - physiopathology; Image Processing, Computer-Assisted; Male; Medical sciences; Miscellaneous. Osteoarticular involvement in other diseases; tilt test; Tilt-Table Test; fractal analysis; Chronic fatigue syndrome; tilt test; Human; Nervous system diseases; Arrhythmia; Diseases of the osteoarticular system; Cardiovascular disease; Excitability disorder; Vascular disease; Heart rate; Postural hypotension; Symptomatology; Striated muscle disease; Tachycardia; Heart disease; Diseases of the autonomic nervous system; Instability; Clinical investigation; Blood pressure; Hemodynamics; Postural fitting; Quantitative analysis
• ISSN: 0049-0172; 1532-866X
• DOI: 10.1053/sarh.2001.27738

Objectives: To evaluate the cardiovascular response to postural challenge in patients with chronic fatigue syndrome (CFS) and to determine whether the degree of instability of the cardiovascular response may aid in diagnosing CFS. Methods: Patients with CFS (n = 25) and their age- and gender-matched healthy controls (n = 37), patients with fibromyalgia (n = 30), generalized anxiety disorder (n = 15), and essential hypertension (n = 20) were evaluated with the aid of a standardized tilt test. The blood pressure (BP) and heart rate (HR) were recorded during 10 minutes of recumbence and 30 minutes of head-up tilt. We designated BP changes as the differences between successive BP values and the last recumbent BP. The average and standard deviation (SD) were calculated. Time curves of BP differences were loaded into a computerized image analyzer, and their outline ratios and fractal dimensions were measured. HR changes were determined similarly. The average and SD of the parameters were calculated, and intergroup comparisons were performed. Results: On multivariate analysis, the independent predictors of CFS patients versus healthy controls were the fractal dimension of absolute values of the systolic BP changes (SYST-FD.abs), the standard deviation of the current values of the systolic BP changes (SYST-SD.cur), and the standard deviation of the current values of the heart rate changes (HR-SD.cur). The following equation was deduced to calculate the hemodynamic instability score (HIS) in the individual patient: HIS = 64.3303 + (SYST-FD.abs × −68.0135) + (SYST-SD.cur × 111.3726) + (HR-SD.cur × 60.4164). The best cutoff differentiating CFS from the healthy controls was −0.98. HIS values >−0.98 were associated with CFS (sensitivity 97%, specificity 97%). The HIS differed significantly between CFS and other groups (P <.0001) except for generalized anxiety disorder. Group averages (SD) of HIS were CFS = +3.72 (5.02), healthy = −4.62 (2.26), fibromyalgia = −3.27 (2.63), hypertension = −5.53 (2.24), and generalized anxiety disorder = +1.08 (5.2). Conclusion: The HIS adds objective criteria confirming the diagnosis of CFS. Semin Arthritis Rheum 31:199-208. Copyright © 2001 by W.B. Saunders Company