Orthostatic intolerance in chronic fatigue syndrome

Figures

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  Fig. 1. Pre-exercise Dizziness and Lightheadedness Scores. CFS subjects reported significantly more Dizziness and Lightheadedness than controls while supine and standing. Absence of symptoms was reported in 14/25 controls and 6/39 CFS subjects (FET, p < 0.0001). The connected dots indicate trends for Dizziness and Lightheadedness to increase in controls and CFS when standing up. Black bars indicate p < 0.05 by Mann–Whitney U test between CFS and controls for supine and standing symptoms

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  Fig. 2. Average Recumbent and Standing Dizziness and Lightheadedness Scores in POTS, STOPP, and START. Each pair of symbols shows the average scores while recumbent (left) and standing (right). CFS POTS (blue), STOPP (red), and START (green) had significantly higher symptoms between recumbent Dizziness and Lightheadedness after 5 min of standing. In contrast, controls had no significant changes in symptoms between the average of all recumbent and standing measurements even if they had postural tachycardia before and after (POTS, blue) or only after exercise (START, green). Black bars indicate P < 0.05, Wilcoxon Signed-Rank test between recumbent and standing symptoms

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  Fig. 3. Recumbent and Standing Dizziness and Lightheaded Symptoms in Stratified Groups. Controls and CFS were stratified based on ROC thresholds of 2. Four controls had Dizziness and Lightheadedness symptoms only when standing. The other 21 controls were asymptomatic. Eleven CFS subjects reported scores < 2 while recumbent and standing; 8 had no Dizziness and 6 had no Lightheadedness. For Persistent OI, 16 reported recumbent and standing symptoms ≥ 2, and, in Postural OI, 12 reported only standing complaints ≥ 2. CFS subjects with recumbent and standing complaints ≥ 2 had significantly higher symptoms compared CFS subjects with no symptoms and those only with standing symptoms. Lines indicate trend of score from recumbent to standing. *p < 0.05 Mann–Whitney U test Postural OI controls vs. No OI controls. Black bars indicate p < 0.05, Mann–Whitney U test vs. CFS No OI and CFS Persistent OI CFS group for recumbent and standing symptoms