Chronic fatigue syndrome and impaired peripheral pulse characteristics on orthostasis–a new potential diagnostic biomarker

Abstract:

Autonomic nervous system dysfunction is frequently reported in chronic fatigue syndrome (CFS) with orthostatic intolerance, a common symptom that can be objectively assessed. The frequent finding of autonomic dysfunction and symptoms on standing has the potential to provide a diagnostic biomarker in chronic fatigue. In this study we explored the clinical value of non-invasive optical multi-site photoplethysmography (PPG) technology to assess cardiovascular responses to standing.

Multi-site PPG pulses were collected from tissue pads of the ears, fingers and toes of 14 patients with CFS and 14 age-matched sedentary subjects using a measurement protocol of a 10 min baseline (subject supine) followed by 3 min of tilting on a tilt table (head-up to 70°). Percentage change in pulse timing (pulse transit time, PTTf) and pulse amplitude (AMP) at each site were calculated using beat-to-beat pulse wave analysis.

A significant reduction in the overall pulse timing response to controlled standing was found for the CFS group (using summed absolute percentage change in PTTf for ear, finger and toe sites, median change of 26% for CFS and 37% for control with p = 0.002).

There were no significant differences between subject groups for the AMP measure at any site. Changes in AMP with tilt were, however, weakly significantly and negatively correlated with fatigue severity (p < 0.05). Receiver operating characteristic (ROC) analysis of timing measures produced an area under the curve of 0.81. Experimental linear discriminant classification analysis comparing both timing and amplitude measures produced an overall diagnostic accuracy of 82%.

Pulse wave abnormalities have been observed in CFS and represent a potential objective measure to help differentiate between CFS patients and healthy controls.

 

Source: Allen J, Murray A, Di Maria C, Newton JL. Chronic fatigue syndrome and impaired peripheral pulse characteristics on orthostasis–a new potential diagnostic biomarker. Physiol Meas. 2012 Feb;33(2):231-41. doi: 10.1088/0967-3334/33/2/231. Epub 2012 Jan 25. https://www.ncbi.nlm.nih.gov/pubmed/22273713

 

Postural neurocognitive and neuronal activated cerebral blood flow deficits in young chronic fatigue syndrome patients with postural tachycardia syndrome

Abstract:

Neurocognition is impaired in chronic fatigue syndrome (CFS). We propose that the impairment relates to postural cerebral hemodynamics.

Twenty-five CFS subjects and twenty control subjects underwent incremental upright tilt at 0, 15, 30, 45, 60, and 75° with continuous measurement of arterial blood pressure and cerebral blood flow velocity (CBFV). We used an n-back task with n ranging from 0 to 4 (increased n = increased task difficulty) to test working memory and information processing. We measured n-back outcomes by the number of correct answers and by reaction time. We measured CBFV, critical closing pressure (CCP), and CBFV altered by neuronal activity (activated CBFV) during each n value and every tilt angle using transcranial Doppler ultrasound.

N-back outcome in control subjects decreased with n valve but was independent of tilt angle. N-back outcome in CFS subjects decreased with n value but deteriorated as orthostasis progressed. Absolute mean CBFV was slightly less than in control subjects in CFS subject at each angle. Activated CBFV in control subjects was independent of tilt angle and increased with n value.

In contrast, activated CBFV averaged 0 in CFS subjects, decreased with angle, and was less than in control subjects. CCP was increased in CFS subjects, suggesting increased vasomotor tone and decreased metabolic control of CBFV. CCP did not change with orthostasis in CFS subjects but decreased monotonically in control subjects, consistent with vasodilation as compensation for the orthostatic reduction of cerebral perfusion pressure.

Increasing orthostatic stress impairs neurocognition in CFS subjects. CBFV activation, normally tightly linked to cognitive neuronal activity, is unrelated to cognitive performance in CFS subjects; the increased CCP and vasomotor tone may indicate an uncoupling of the neurovascular unit during orthostasis.

 

Source: Stewart JM, Medow MS, Messer ZR, Baugham IL, Terilli C, Ocon AJ. Postural neurocognitive and neuronal activated cerebral blood flow deficits in young chronic fatigue syndrome patients with postural tachycardia syndrome. Am J Physiol Heart Circ Physiol. 2012 Mar 1;302(5):H1185-94. doi: 10.1152/ajpheart.00994.2011. Epub 2011 Dec 16. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3311460/ (Full article)

 

Small heart with low cardiac output for orthostatic intolerance in patients with chronic fatigue syndrome

Abstract:

BACKGROUND: The etiology of chronic fatigue syndrome (CFS) is unknown. Orthostatic intolerance (OI) is common in CFS patients. Recently, small heart with low cardiac output has been postulated to be related to the genesis of both CFS and OI.

HYPOTHESIS: Small heart is associated with OI in patients with CFS.

METHODS: Study CFS patients were divided into groups of 26 (57%) CFSOI(+) and 20 (43%) CFSOI(-) according to the presence or absence of OI. In addition, 11 OI patients and 27 age- and sex-matched control subjects were studied. Left ventricular (LV) dimensions and function were determined echocardiographically.

RESULTS: The mean values of cardiothoracic ratio, systemic systolic and diastolic pressures, LV end-diastolic dimension, LV end-systolic dimension, stroke volume index, cardiac index, and LV mass index were all significantly smaller in CFSOI(+) patients than in CFSOI(-) patients and healthy controls, and also in OI patients than in controls. A smaller LV end-diastolic dimension (<40 mm) was significantly (P<0.05) more prevalently noted in CFSOI(+) (54%) and OI (45%) than in CFSOI(-) (5%) and controls (4%). A lower cardiac index (<2 L/min/mm(2)) was more prevalent in CFSOI(+) (65%) than in CFSOI(-) (5%, P<0.01), OI (27%), and controls (11%, P<0.01).

CONCLUSIONS: A small size of LV with low cardiac output was noted in OI, and its degree was more pronounced in CFSOI(+). A small heart appears to be related to the genesis of OI and CFS via both cerebral and systemic hypoperfusion. CFSOI(+) seems to constitute a well-defined and predominant subgroup of CFS.

© 2011 Wiley Periodicals, Inc.

 

Source: Miwa K, Fujita M. Small heart with low cardiac output for orthostatic intolerance in patients with chronic fatigue syndrome. Clin Cardiol. 2011 Dec;34(12):782-6. doi: 10.1002/clc.20962. Epub 2011 Nov 28. http://onlinelibrary.wiley.com/doi/10.1002/clc.20962/full (Full article)

 

Increasing orthostatic stress impairs neurocognitive functioning in chronic fatigue syndrome with postural tachycardia syndrome

Abstract:

CFS (chronic fatigue syndrome) is commonly co-morbid with POTS (postural tachycardia syndrome). Individuals with CFS/POTS experience unrelenting fatigue, tachycardia during orthostatic stress and ill-defined neurocognitive impairment, often described as ‘mental fog’. We hypothesized that orthostatic stress causes neurocognitive impairment in CFS/POTS related to decreased CBFV (cerebral blood flow velocity).

A total of 16 CFS/POTS and 20 control subjects underwent graded tilt table testing (at 0, 15, 30, 45, 60 and 75°) with continuous cardiovascular, cerebrovascular, and respiratory monitoring and neurocognitive testing using an n-back task at each angle. The n-back task tests working memory, concentration, attention and information processing. The n-back task imposes increasing cognitive challenge with escalating (0-, 1-, 2-, 3- and 4-back) difficulty levels. Subject dropout due to orthostatic presyncope at each angle was similar between groups.

There were no n-back accuracy or RT (reaction time) differences between groups while supine. CFS/POTS subjects responded less correctly during the n-back task test and had greater nRT (normalized RT) at 45, 60 and 75°. Furthermore, at 75° CFS/POTS subjects responded less correctly and had greater nRT than controls during the 2-, 3- and 4-back tests. Changes in CBFV were not different between the groups and were not associated with n-back task test scores.

Thus we conclude that increasing orthostatic stress combined with a cognitive challenge impairs the neurocognitive abilities of working memory, accuracy and information processing in CFS/POTS, but that this is not related to changes in CBFV. Individuals with CFS/POTS should be aware that orthostatic stress may impair their neurocognitive abilities.

 

Source: Ocon AJ, Messer ZR, Medow MS, Stewart JM. Increasing orthostatic stress impairs neurocognitive functioning in chronic fatigue syndrome with postural tachycardia syndrome. Clin Sci (Lond). 2012 Mar;122(5):227-38. doi: 10.1042/CS20110241. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3368269/ (Full article)

 

Fatigue severity remains stable over time and independently associated with orthostatic symptoms in chronic fatigue syndrome: a longitudinal study

Abstract:

OBJECTIVES: to examine fatigue variability over time in chronic fatigue syndrome (CFS) and the effect of other symptoms on its predictability.

DESIGN: longitudinal cohort study of patients with CFS (Fukuda criteria).

SETTING: specialist CFS clinical service.

SUBJECTS: phase 1: 100 patients who participated in a study of CFS symptoms in 2005 were revisited in 2009. Phase 2: 25 patients completed fatigue diaries to address intra- and inter-day variability in perceived fatigue.

MAIN OUTCOME MEASURES: phase 1: subjects completed fatigue impact scale (FIS), Epworth sleepiness scale (ESS), orthostatic grading scale (OGS) and hospital anxiety and depression scale (HADS). Changes in variables represented the differences between 2005 and 2009. Phase 2: subjects rated fatigue on a scale of 0 (no fatigue) to 10 (severe fatigue) four times a day for 5 weeks.

RESULTS: symptom assessment tools were available in both 2005 and 2009 for 74% of patients. FIS and HADS depression (HAD-D) and anxiety (HAD-A) scores significantly improved during follow-up whereas ESS and OGS remained stable. FIS improved in 29/74 (39%) subjects, and by ≥ 10 points in 19 (26%). FIS worsened by ≥ 10 points in 33/74 (45%) subjects. On multivariate analysis, independent predictors of current fatigue (FIS in 2009) were FIS in 2005, HAD-D in 2009, OGS in 2009 and change in HAD-A. Reported fatigue was stable from week to week and from day to day. Patients reported higher fatigue in the morning (mean ± SD; 6.4 ± 2), becoming significantly lower at lunchtime (6.2 ± 2; P < 0.05) and increasing again to 7 ± 2 at bedtime.

CONCLUSIONS: current fatigue is independently associated with current autonomic symptom burden, current depression and change in anxiety during follow-up. These findings have implications for targeted symptom management in CFS.

 

Source: Jones DE, Gray J, Frith J, Newton JL. Fatigue severity remains stable over time and independently associated with orthostatic symptoms in chronic fatigue syndrome: a longitudinal study. J Intern Med. 2011 Feb;269(2):182-8. doi: 10.1111/j.1365-2796.2010.02306.x. Epub 2010 Nov 14. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2796.2010.02306.x/full (Full article)

 

Are symptoms of ‘hypoglycemia’ in Chronic Fatigue Syndrome (CFS) associated with hypoglycemia or orthostatic intolerance in young people?

Background: Symptoms of nausea, feeling faint, malaise and mild anxiety are common in young people with CFS and popularly attributed to ‘hypoglycemia’ resulting in various dietary interventions with little reported improvement.

Objectives: To determine whether the symptoms are associated with measured hypoglycaemia using continuous tissue glucose monitoring or whether these symptoms are associated with documented orthostatic intolerance.

Methods: Nine young people with CFS (mean age 20 years) and mean duration of 4.5 years with persistently troublesome symptoms were compared with 10 healthy adult controls without diabetes. Each subject agreed to 3 days Continuous Glucose Monitoring System (Medtronic CGMS). This is routinely used in adolescent diabetics to document food intake, tissue glucose levels and activity levels to monitor control.

Subsequently 8 of these had formal cardiac tilt table testing where heart rate and blood pressure are measured supine and during 70 degree head-up tilt for up to 10 minutes to assess the presence orthostatic intolerance (either postural orthostatic tachycardia (POTS) or neurocardiogenic hypotensive syndrome). If positive, appropriate medical management of increasing salt and fluids, gentle improvement of muscle tone and blood pressure support medications, was implemented.

Results: The tissue glucose was calibrated with the blood glucose and all fell within acceptable normal range. There was statistical (but not clinical) significance in average tissue glucose in CFS subjects. 6% of time in controls and 16.8% in CFS was spent in the range <4mmol/L glucose (95% CI -23% to +2%, p=0.1) suggesting weak evidence for a difference given the variability and small sample size. The reported presence of symptoms throughout the day was not associated with significant reduction in tissue glucose levels.

Six had confirmed evidence for POTS, one for neurocardiogenic syndrome and one for a combination of both. All 8 reported improvement in all symptoms especially nausea, dizziness and malaise with active treatment of their orthostatic intolerance.

Conclusion: This study could not confirm a link between putative symptoms of ‘hypoglycemia’ and documented hypoglycemia. This suggests that symptoms frequently attributed to ‘hypoglycemia’ may be due to orthostatic intolerance and further investigation and management of this condition provides more reported relief for these troublesome symptoms.

Dr Kathy Rowe, Senior Consultant Paediatrician, Department of General Medicine, Royal Children’s Hospital, Melbourne, Victoria, Australia 3052
kathy.rowe@rch.org.au  No conflicts of interest to declare. RCH internally funded.

 

Source: Katherine Rowe, Rebecca Gebert, Susan Donath, Angas Hamer & Fergus Cameron. Are symptoms of ‘hypoglycemia’ in Chronic Fatigue Syndrome (CFS) associated with hypoglycemia or orthostatic intolerance in young people? From: The IACFS/ME 2016 Conference Syllabus.

 

Orthostatic symptoms predict functional capacity in chronic fatigue syndrome: implications for management

Abstract:

OBJECTIVES: To establish the relationship between the functional impairment experienced by Chronic fatigue syndrome (CFS) patients and the symptoms frequently experienced by those with CFS; specifically cognitive impairment, fatigue and orthostatic symptoms.

DESIGN: Cross sectional questionnaire survey.

SETTING: Specialist CFS Clinical Service.

SUBJECTS: Ninety-nine Fukuda diagnosed CFS and 64-matched controls.

MAIN OUTCOME MEASURES: Symptom and functional assessment tools completed and returned by post included; PROMIS HAQ (Patient-Reported Outcomes Measurement Information System, Health Assessment Questionnaire), CFQ (Cognitive Failures Questionnaire), FIS (Fatigue Impact Scale) and OGS (Orthostatic Grading Scale) assessment tools.

RESULTS: CFS patients experience greater functional impairment than controls [mean (95% CI) PROMIS HAQ scores CFS 36 (31-42) vs. controls 6 (2-10); P < 0.0001], especially in the functional domains of activities and reach. Poorer functional ability impairment is significantly associated with greater cognitive impairment (P = 0.0002, r = 0.4), fatigue (P < 0.0001, r = 0.5) and orthostatic symptoms (P < 0.0001, r = 0.6). However, only orthostatic symptoms (OGS) independently associated with functional impairment (beta = 0.4, P = 0.01).

CONCLUSION: Treatment of orthostatic symptoms in CFS has the potential to improve functional capacity and so improve quality of life.

 

Source: Costigan A, Elliott C, McDonald C, Newton JL. Orthostatic symptoms predict functional capacity in chronic fatigue syndrome: implications for management. QJM. 2010 Aug;103(8):589-95. doi: 10.1093/qjmed/hcq094. Epub 2010 Jun 9. http://qjmed.oxfordjournals.org/content/103/8/589.long (Full article)

 

Home orthostatic training in chronic fatigue syndrome–a randomized, placebo-controlled feasibility study

Abstract:

BACKGROUND: Orthostatic (Tilt)-training is an effective treatment for neurally mediated hypotension (NMH). NMH is a frequent finding in chronic fatigue syndrome (CFS). We evaluated home orthostatic training (HOT) in CFS in a randomized placebo-controlled feasibility study.

METHODS: Thirty-eight patients with CFS (Fukuda Criteria) were randomly allocated to daily tilt training (n = 19) or sham training (n = 19) for 6 months. Haemodynamic responses to standing were performed in all subjects using continuous technology (Taskforce) at enrolment, week 1, 4 and 24. Symptom response and compliance were assessed using diaries.

RESULTS: Two patients (one from each arm) withdrew from the study. Fourteen patients in each group complied completely or partially, and patients found the training manageable and achievable. Compared to the sham group, blood pressure while standing dropped to 8.0 mmHg less in the HOT group at 4 weeks (95% CI: 1.0 to 15.0, P = 0.03). At 4 weeks, the HOT group had higher total peripheral resistance compared to the sham group; mean difference 70.2, 95% CI: -371.4 to 511.8. Changes were maintained at 6 months. There was no significant difference in fatigue between groups at 4 weeks (mean difference 1.4, 95% CI: -13.5 to 16.2), but there was a trend towards improvement in fatigue at 6 months. Compliers had lower fatigue compared to non-compliers.

CONCLUSIONS: A placebo-controlled study of HOT in CFS is feasible. HOT is well tolerated and generally complied with. A likely physiological rationale for HOT in CFS is related to reductions in orthostatic intolerance. An adequately powered study including strategies to enhance compliance is warranted.

 

Source: Sutcliffe K, Gray J, Tan MP, Pairman J, Wilton K, Parry SW, Newton JL. Home orthostatic training in chronic fatigue syndrome–a randomized, placebo-controlled feasibility study. Eur J Clin Invest. 2010 Jan;40(1):18-24. doi: 10.1111/j.1365-2362.2009.02225.x. Epub 2009 Nov 12. https://www.ncbi.nlm.nih.gov/pubmed/19912315

 

Postural orthostatic tachycardia syndrome is an under-recognized condition in chronic fatigue syndrome

Abstract:

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.

RESULTS: 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: Hoad A, Spickett G, Elliott J, Newton J. Postural orthostatic tachycardia syndrome is an under-recognized condition in chronic fatigue syndrome. QJM. 2008 Dec;101(12):961-5. doi: 10.1093/qjmed/hcn123. Epub 2008 Sep 19. http://qjmed.oxfordjournals.org/content/101/12/961.long (Full article)

 

A matched case control study of orthostatic intolerance in children/adolescents with chronic fatigue syndrome

Abstract:

This study aimed to define cardiovascular and heart rate variability (HRV) changes following head-up tilt (HUT) in children/adolescents with chronic fatigue syndrome (CFS) in comparison to age- and gender-matched controls.

Twenty-six children/adolescents with CFS (11-19 y) and controls underwent 70-degree HUT for a maximum of 30 min, but returned to horizontal earlier at the participant’s request with symptoms of orthostatic intolerance (OI) that included lightheadedness.

Using electrocardiography and beat-beat finger blood pressure, a positive tilt was defined as OI with 1) neurally mediated hypotension (NMH); bradycardia (HR <75% of baseline), and hypotension [systolic pressure (SysP) drops >25 mm Hg)] or 2) postural orthostatic tachycardia syndrome (POTS); HR increase >30 bpm, or HR >120 bpm (with/without hypotension).

Thirteen CFS and five controls exhibited OI generating a sensitivity and specificity for HUT of 50.0% and 80.8%, respectively. POTS without hypotension occurred in seven CFS subjects but no controls. POTS with hypotension and NMH occurred in both. Predominant sympathetic components to HRV on HUT were measured in CFS tilt-positive subjects.

In conclusion, CFS subjects were more susceptible to OI than controls, the cardiovascular response predominantly manifest as POTS without hypotension, a response unique to CFS suggesting further investigation is warranted with respect to the pathophysiologic mechanisms involved.

 

Source: Galland BC, Jackson PM, Sayers RM, Taylor BJ. A matched case control study of orthostatic intolerance in children/adolescents with chronic fatigue syndrome. Pediatr Res. 2008 Feb;63(2):196-202. https://www.ncbi.nlm.nih.gov/pubmed/18091356