ORTHOSTATIC INTOLERANCE IN CFS

Summary

Principal Investigator: R Freeman
Affiliation: Harvard University
Country: USA
Abstract: DESCRIPTION (Adapted from the Investigator's Application): The over-all objectives of this proposal are: (1) to delineate the pathophysiology and pathogenesis of orthostatic intolerance in the chronic fatigue syndrome (CFS) (2) to investigate the role of orthostatic intolerance in producing the symptoms of CFS and (3) to use this information to apply physiologically appropriate therapeutic interventions and thereby decrease the symptoms of fatigue. The investigators plan to determine the physiological characteristics of orthostatic intolerance in CFS patients and healthy controls, characterize the differences in functional exercise capacity among CFS patients and between CFS patients and controls; and identify the relationships between the physiological measures of orthostatic intolerance, measures of functional exercise capacity, symptoms of orthostatic intolerance and symptoms of fatigue. Cardiovascular autonomic functions are to be assessed using standard tests of the sympathetic and parasympathetic nervous system; arterial baroreflex gain is to be measured using the heart rate and muscle sympathetic nerve activity response to pharmacological provocations; the cardiopulmonary baroreflex functions is to be assessed in response to graded central hypovolemia elicited by lower body negative pressure; plasma volume will be measured using the Evans Blue dye method; venous compliance assessed with venous occlusion plethysmography, Assessment of neurohumoral status and the functional exercise capacity is also to be included. These measures, which comprise the elements of orthostatic tolerance, will be compared with matched healthy controls. The relationships between these variables and the role of covariates such as the level of physical activity and psychiatric state, determined with standardized instruments, are to be analyzed using multivariate statistics.
Funding Period: 1998-02-01 - 2002-01-31
more information: NIH RePORT

Top Publications

  1. ncbi Nonlinearities and asymmetries of the human cardiovagal baroreflex
    Brian E Hunt
    Research and Training Institute, Hebrew Rehabilitation Center for Aged, Boston, MA, USA
    Am J Physiol Regul Integr Comp Physiol 288:R1339-46. 2005
  2. ncbi Orthostatic dyspnea: a neglected symptom of orthostatic hypotension
    Christopher H Gibbons
    Autonomic and Peripheral Nerve Laboratory, Dept. of Neurology, Beth Israel Deaconess Medical Center, 1 Deaconess Road, Boston, MA 02215, USA
    Clin Auton Res 15:40-4. 2005
  3. ncbi Sympathetic neural activity, sex dimorphism, and postural tachycardia syndrome
    Istvan Bonyhay
    Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
    Ann Neurol 61:332-9. 2007
  4. ncbi Pregabalin for painful HIV neuropathy: a randomized, double-blind, placebo-controlled trial
    D M Simpson
    Mount Sinai School of Medicine, New York, NY, USA
    Neurology 74:413-20. 2010

Scientific Experts

Detail Information

Publications4

  1. ncbi Nonlinearities and asymmetries of the human cardiovagal baroreflex
    Brian E Hunt
    Research and Training Institute, Hebrew Rehabilitation Center for Aged, Boston, MA, USA
    Am J Physiol Regul Integr Comp Physiol 288:R1339-46. 2005
    ..Moreover, of the parameters produced by the symmetric sigmoid model, only the response range provides unique information beyond that of reflex gain...
  2. ncbi Orthostatic dyspnea: a neglected symptom of orthostatic hypotension
    Christopher H Gibbons
    Autonomic and Peripheral Nerve Laboratory, Dept. of Neurology, Beth Israel Deaconess Medical Center, 1 Deaconess Road, Boston, MA 02215, USA
    Clin Auton Res 15:40-4. 2005
    ..05). In this study, dyspnea was frequently associated with OH. Ventilation perfusion mismatch, due to inadequate perfusion of ventilated lung apices may be the most likely underlying cause of orthostatic dyspnea in patients with OH...
  3. ncbi Sympathetic neural activity, sex dimorphism, and postural tachycardia syndrome
    Istvan Bonyhay
    Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
    Ann Neurol 61:332-9. 2007
    ..To elucidate the mechanisms whereby postural tachycardia syndrome (POTS) patients maintain orthostatic blood pressure and explain the greater prevalence of female cases in POTS cohorts...
  4. ncbi Pregabalin for painful HIV neuropathy: a randomized, double-blind, placebo-controlled trial
    D M Simpson
    Mount Sinai School of Medicine, New York, NY, USA
    Neurology 74:413-20. 2010
    ..Pregabalin is effective in several neuropathic pain syndromes. This trial evaluated its efficacy, safety, and tolerability for treatment of painful HIV-associated neuropathy...