Journal of IiME Volume 8 Issue 1 day cardiopulmonary exercise test at Ithaca College under the supervision of Dr. Betsy Keller. #IIMEC9 Abstract: Markers of Post-exertional Malaise 1Maureen R. Hanson, 1Ludovic Giloteaux, 2Xiaojing Lu, 2Jason W. Locasale, 3Betsy A. Keller 1Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA 2Division of Nutritional Sciences, Cornell University, Ithaca, NY, USA 3Department of Exercise & Sport Sciences, Ithaca College Ithaca, NY, USA ME/CFS patients often report an increase in symptoms following levels of physical or cognitive activity that would not be challenging to healthy subjects, a problem which is termed post-exertional malaise. Reports have demonstrated that healthy subjects, as well as subjects with heart or renal failure or lung diseases, are able to reproduce their maximum oxygen consumption (VO2max) and/or VO2 at ventilatory threshold (VT) when they undergo repeated cardiopulmonary exercise tests (CPET). In contrast, detrimental effects of an exercise challenge on the physiology of individuals with ME/CFS can be documented by objective measures obtained during two CPETs. Because subjects cannot willfully alter the maximum amount of oxygen they inhale nor the amount of carbon dioxide they exhale, measurement of these parameters provides an objective indicator of an individual’s physiological function that cannot be explained by deliberate malingering or by psychiatric illness. After induction of post-exertional malaise by an initial CPET, ME/CFS patients often exhibit abnormal physiological and/or autonomic nervous system responses and are usually unable to repeat either their VO2max and/or VT, which is a measure of the anaerobic threshold, or they show symptoms of autonomic dysfunction. Anaerobic threshold is the exercise intensity at which metabolism transitions to anaerobic energy production, which is less efficient and results in accumulation of lactic acid. We have observed patients with ME/CFS who become prematurely “anaerobic” at low work levels. After an exercise challenge, even modest activities, such as lying quietly while watching television or sitting and eating, require some patients to use anaerobic metabolism. Other patients exhibit Metabolic Equivalent of Task (MET) May 2014 levels at maximal exertion of 4.0 or less, while 4.0 METs are required to do such simple activities as hanging laundry, sweeping a sidewalk or climbing stairs slowly. A simple strategy can be used to discern biochemical and metabolic abnormalities in individuals experiencing post-exertional malaise. By collecting blood samples before an exercise challenge and 24 hours afterwards, assays can be performed to determine which molecules have changed in concentration. We will discuss the data that is currently available about exercise-induced changes in amounts of plasma molecules. Dr Andreas Kogelnik Director of the Open Medicine Institute, USA Dr Andreas Kogelnik is the Founding Director of the Open Medicine Institute, a collaborative, communitybased translational research institute dedicated to personalized medicine with a human touch while using the latest advances in medicine, informatics, genomics, and biotechnology. The Institute works closely with the Open Medicine Clinic and other clinics to conduct research and apply new knowledge back into clinical practice. Dr. Kogelnik received his M.D. from Emory University School of Medicine in Atlanta and his Ph.D. in bioengineering/bioinformatics from the Georgia Institute of Technology. Subsequently, he completed is residency in Internal Medicine and a Fellowship in Infectious Diseases at Stanford University and its affiliated hospitals. Following his clinical training, he remained at Stanford with NIH funding to engage in post-doctoral research in microbiology, immunology and bioinformatics with Dr. Ellen Jo Baron and Dr. Stanley Falkow, where he explored host-response profiles in severely ill patients. Invest in ME (Charity Nr. 1114035) www.investinme.org Page 46 of 52
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