Fig. 1
Correlation between the percent CBF reduction at end-tilt compared to supine and the percentage peak VO2 for all ME/CFS patients (n = 199 and HC (n = 22). CBF cerebral blood flow in ml/min/kg, dOH delayed orthostatic hypotension, HC healthy controls, normHRBP normal heart rate and blood pressure response during HUT, POTS postural orthostatic tachycardia syndrome, percent VO2 oxygen consumption as percentage of normal values of a population study [19]. The insert figure above right shows the linear regression analysis of HC and norm HRBP patients with a normal CBF (OI-) reduction during HUT: see Additional file 1