Orthostatic Stress Impairs Cognition

16 subjects who met criteria for CFS and postural orthostatic tachycardia syndrome (POTS) were Tilt-test-215x300compared to 20 healthy volunteers. Subjects performed cognitive testing while lying flat, then while tilted to 15, 30,45,60 and 70 degrees for 10 minutes at each angle. The test was stopped if the subject became hypotensive or requested to stop. The two groups had similar drop-out rates. At baseline, the subjects had increased heart rate and respiratory rates, but comparable intelligence and cognitive performance. However, during the tilt, compared to controls the CFS-POTS subjects cognitive performance worsened as orthostatic stress increased. The subjects had decreased accuracy and longer normalized reaction time during difficult tasks imposed on orthostatic stress. This study, performed at New York Medical College, was funded by the Solve ME/CFS Initiative. (Clinical Science, Sept. 15, 2011)

Tags: , September 15, 2011