[Note: The full text of this article was posted to the co-cure listserv 9/28/08.]
Background: It has been suggested that postural orthostatic tachycardia syndrome (POTS) be considered in the differential diagnosis of those with chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME). Currently, measurement of haemodynamic response to standing is not recommended in the UK NICE CFS/ME guidelines.
Objectives: To determine prevalence of POTS in patients with CFS/ME.
Design: Observational cohort study.
Methods: Fifty-nine patients with CFS/ME (Fukuda criteria) and 52 age- and sex-matched controls underwent formal autonomic assessment in the cardiovascular laboratory with continuous heart rate and beat-to-beat blood pressure measurement (Task Force, CNSystems, Graz Austria). Haemodynamic responses to standing over 2 min were measured.
POTS was defined as symptoms of orthostatic intolerance associated with an increase in heart rate from the supine to upright position of >30 beats per minute or to a heart rate of >120 beats per minute on standing.
• Maximum heart rate on standing was significantly higher in the CFS/ME group compared with controls (106 +/- 20 vs. 98 +/- 13; P = 0.02).
• Of the CFS/ME group, 27% (16/59) had POTS compared with 9% (5) in the control population (P = 0.006).
• This difference was predominantly related to the increased proportion of those in the CFS/ME group whose heart rate increased to >120 beats per minute on standing (P = 0.0002).
• Increasing fatigue was associated with increase in heart rate (P = 0.04; r(2) = 0.1).
Conclusion: POTS is a frequent finding in patients with CFS/ME. We suggest that clinical evaluation of patients with CFS/ME should include response to standing. Studies are needed to determine the optimum intervention strategy to manage POTS in those with CFS/ME.
Source: QJM: Monthly Journal of the Association of Physicians, Sep 19, 2008. [Epub ahead of print] PMID: 18805903, by Hoad A, Spickett G, Elliott J, Newton J. Northern CFS/ME Clinical Network, Equinox House, Newcastle upon Tyne; ME NorthEast, County Durham and Falls and Syncope Service, Institute of Cellular Medicine, Newcastle University, Newcastle, UK. [E-mail: firstname.lastname@example.org ]