Tag: deconditioning

Exercise Pathophysiology in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Post-Acute Sequelae of SARS-CoV-2: More in Common Than Not?

Abstract:

Topic importance: Post-Acute Sequelae of SARS-CoV-2 (PASC) is a long-term consequence of acute infection from coronavirus disease 2019 (COVID-19). Clinical overlap between PASC and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) has been observed, with shared symptoms including intractable fatigue, postexertional malaise, and orthostatic intolerance. The mechanistic underpinnings of such symptoms are poorly understood.

Review findings: Early studies suggest deconditioning as the primary explanation for exertional intolerance in PASC. Cardiopulmonary exercise testing (CPET) reveals perturbations related to systemic blood flow and ventilatory control associated with acute exercise intolerance in PASC, which are not typical of simple detraining. Hemodynamic and gas exchange derangements in PASC have substantial overlap with those observed with ME/CFS, suggestive of shared mechanisms.

Summary: This review aims to illustrate exercise pathophysiologic commonalities between PASC and ME/CFS that will help guide future diagnostics and treatment.

Source: Joseph P, Singh I, Oliveira R, Capone CA, Mullen MP, Cook DB, Stovall MC, Squires J, Madsen K, Waxman AB, Systrom DM. Exercise Pathophysiology in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Post-Acute Sequelae of SARS-CoV-2: More in Common Than Not? Chest. 2023 Apr 11:S0012-3692(23)00502-0. doi: 10.1016/j.chest.2023.03.049. Epub ahead of print. PMID: 37054777; PMCID: PMC10088277. https://pubmed.ncbi.nlm.nih.gov/37054777/

Comparison of the Degree of Deconditioning in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Patients with and without Orthostatic Intolerance

Abstract:

Background: Orthostatic intolerance (OI) is a core finding in individuals with myalgic encephalomyelitis /chronic fatigue syndrome (ME/CFS). Deconditioning is often proposed as an important determinant for OI. Deconditioning can be objectively classified using the predicted peak oxygen consumption (%VO2 peak) values as derived from cardiopulmonary exercise testing (CPET) and OI can be objectively quantified using cerebral blood flow (CBF) changes during tilt testing. Therefore, if deconditioning contributes to OI, a correlation between peak VO2 and the %CBF reduction is expected.

Methods and results: 18 healthy controls (HC) and 122 ME/CFS patients without hypotension or tachycardia on tilt testing were studied. Deconditioning was classified as follows: %VO2 peak ≥85%= no deconditioning, %VO2 peak 65-85%= mild deconditioning, %VO2 peak<65%= severe deconditioning. HC had higher %VO2 peak compared to ME/CFS patients (p<0.0001). ME/CFS patients had significantly larger CBF reduction than HC (p<0.0001). No relation between the degree of deconditioning by the %VO2 peak and the %CBF reduction in ME/CFS patients was found. Moreover, we separately analyzed ME/CFS patients without an abnormal CBF reduction. Despite equal CBF reductions compared to HC and large differences between these patients and the patients with an abnormal CBF reduction, cardiac index (CI) changes (measured by suprasternal Doppler) were significantly less compared to ME/CFS patients with an abnormal CBF reduction (p<0.0001) but larger than in HC (p=0.004). Despite these different hemodynamic findings, %VO2 values were not different between the two patient groups, argumenting again against the causative role of hemodynamic abnormalities in deconditioning.

Conclusion: In ME/CFS patients without hypotension or tachycardia there is no relation between the %VO2 peak during CPET and the %CBF and %CI reduction during tilt testing, whether or not patients have an abnormal CBF reduction during tilt testing. It suggests again that deconditioning does not play an important role in OI.

Source: VAN CAMPEN, C (Linda) M.C.; VISSER, Frans C.. Comparison of the Degree of Deconditioning in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Patients with and without Orthostatic Intolerance. Medical Research Archives, [S.l.], v. 10, n. 6, june 2022. ISSN 2375-1924. Available at: <https://esmed.org/MRA/mra/article/view/2858>. Date accessed: 17 july 2022. doi: https://doi.org/10.18103/mra.v10i6.2858.

The Abnormal Cardiac Index and Stroke Volume Index Changes During a Normal Tilt Table Test in ME/CFS Patients Compared to Healthy Volunteers, are Not Related to Deconditioning

Abstract:

1.1 Background. A small study in ME/CFS (Myalgic Encephalomyelitis/Chronic Fatigue Syndrome) patients undergoing tilt testing, showed that, despite a normal tilt test, stroke volumes and cardiac output were lower than in healthy volunteers. Moreover, it was suggested that this difference was related to deconditioning of patients. Aim of the study. We performed table testing in 150 ME/CFS patients. Stroke volumes and cardiac output were related to the severity of the disease.

1.2 Methods and results. In the patients the severity of the disease was clinically evaluated according to the ME criteria and scored as mild, moderate or severe disease. In a subgroup of 109 patients this clinical diagnosis was confirmed by the physical functioning score of the Rand-36 questionnaire. Significantly lower physical functioning scores (indicating worse functioning) were observed in the more severely affected patients. Stroke Volume Index (SVI) and Cardiac Index (CI) were measured by suprasternal aortic Doppler imaging in the supine position, prior to the tilt, and twice during the tilt. Thirty-seven healthy volunteers underwent the same tilt protocol. In all patients and all healthy volunteers, a normal heart rate and blood pressure response was observed during the tilt. The decreases in SVI and CI during the tilt was significantly larger in patients compared to the SVI and CI decrease in HV. The decrease in SVI and CI were similar and not significantly different between the mild, moderate, and severe ME groups.

1.3 Conclusions. During a normal tilt table test decreases in SVI and CI decrease are significantly greater in ME/CFS patients than in HV, consistent with previous work. The absence of differences between patients with mild, moderate, and severe ME/CFS suggests that the decreases in stroke volumes and cardiac output are not related to deconditioning. Other factors like decreased blood volumes and autonomic dysfunction may cause this difference in the hemodynamic response between ME/CFS patients and HV.

3. Abbreviations

BMI : Body Mass Index

BSA : Body Surface Area

CFS : Chronic Fatigue Syndrome

CI : Cardiac Index

DBP : Diastolic Blood Pressure

HR : Heart Rate

HUT : Head-Up Tilt Test

HV : Healthy Volunteers

IOM : Institute of Medicine

MAP : Mean Blood Pressure

ME : Myalgic Encephalomyelitis

NMH : Neurally Mediated Hypotension

Normal BPHR : normal Blood Pressure and Heart Rate Response During HUT

OI : Orthostatic Intolerance

R36 Phys Funct : Rand-36 Physical Functioning Score

SBP : Systolic Blood Pressure

SVI : Stroke Volume Index

SVRI : Systemic Vascular Resistance Index

VTI : Time-Velocity Integral

Source: van Campen CMC, Visser FC (2018) The Abnormal Cardiac Index and Stroke Volume Index Changes During a Normal Tilt Table Test in ME/CFS Patients Compared to Healthy Volunteers, are Not Related to Deconditioning. J Thrombo Cir: JTC -107. DOI: 10.29011/ JTC -107. 000007 https://www.gavinpublishers.com/articles/Research-Article/Journal-of-Thrombosis-and-Circulation/The-Abnormal-Cardiac-Index-and-Stroke-Volume-Index-Changes-During-a-Normal-Tilt-Table-Test-in-ME-CFS-Patients-Compared-to-Healthy-Volunteers-are-Not-Related-to-Deconditioning (Full article)

Chronic fatigue syndrome: comments on deconditioning, blood volume and resulting cardiac function

Abstract:

Cardiovascular and autonomic dysfunction have been suggested to underlie the symptoms accompanying CFS (chronic fatigue syndrome). In the present issue of Clinical Science, Hurwitz and co-workers have investigated whether deficits were present in cardiac output and blood volume in a cohort of patients with CFS and if these were linked to illness severity and sedentary lifestyle. The results clearly demonstrate reduced cardiac stroke volume and cardiac output in more severely afflicted patients with CFS, which is primarily attributable to a measurable reduction in blood volume. Similar findings are observed in microgravity and bed rest deconditioning, in forms of orthostatic intolerance and, to a lesser extent, in sedentary people. The circulatory consequences of reduced cardiac output may help to account for many of the findings of the syndrome.

You can read the rest of this comment here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4236909/

 

Source: Stewart JM. Chronic fatigue syndrome: comments on deconditioning, blood volume and resulting cardiac function. Clin Sci (Lond). 2009 Oct 19;118(2):121-3. doi: 10.1042/CS20090327. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4236909/ (Full article)

 

A longitudinal study of physical activity and body mass index among persons with unexplained chronic fatigue

Abstract:

OBJECTIVE AND METHODS: A cohort of 100 patients with unexplained chronic fatigue (CF) was assessed longitudinally for 1.5 years to determine if physical activity (kcal expended), exercise capacity (VO(2)max), perceived exertion, and body mass index (BMI) changed over time and were associated with changes in CF-related clinical status.

RESULTS: BMI increased significantly over time but did not predict changes in clinical status. Increasing energy expenditure was associated with increasing vitality and decreasing CF symptom severity over time, and decreasing perceived exertion was associated with increasing physical functioning. However, increasing perceived exertion was also associated with increasing CF symptoms.

CONCLUSIONS: These data do not support models that posit associations between CF and deconditioning.

 

Source: Schmaling KB, Fiedelak JI, Bader J, Buchwald D. A longitudinal study of physical activity and body mass index among persons with unexplained chronic fatigue. J Psychosom Res. 2005 Apr;58(4):375-81. http://www.ncbi.nlm.nih.gov/pubmed/15992573

 

Is physical deconditioning a perpetuating factor in chronic fatigue syndrome? A controlled study on maximal exercise performance and relations with fatigue, impairment and physical activity

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS) patients often complain that physical exertion produces an increase of complaints, leading to a greater need for rest and more time spent in bed. It has been suggested that this is due to a bad physical fitness and that physical deconditioning is a perpetuating factor in CFS. Until now, studies on physical deconditioning in CFS have shown inconsistent results.

METHODS: Twenty CFS patients and 20 matched neighbourhood controls performed a maximal exercise test with incremental load. Heart rate, blood pressure, respiratory tidal volume, O2 saturation, O2 consumption, CO2 production, and blood-gas values of arterialized capillary blood were measured. Physical fitness was quantified as the difference between the actual and predicted ratios of maximal workload versus increase of heart rate. Fatigue, impairment and physical activity were assessed to study its relationship with physical fitness.

RESULTS: There were no statistically significant differences in physical fitness between CFS patients and their controls. Nine CFS patients had a better fitness than their control. A negative relationship between physical fitness and fatigue was found in both groups. For CFS patients a negative correlation between fitness and impairment and a positive correlation between fitness and physical activity was found as well. Finally, it was found that more CFS patients than controls did not achieve a physiological limitation at maximal exercise.

CONCLUSIONS: Physical deconditioning does not seem a perpetuating factor in CFS.

 

Source: Bazelmans E, Bleijenberg G, Van Der Meer JW, Folgering H. Is physical deconditioning a perpetuating factor in chronic fatigue syndrome? A controlled study on maximal exercise performance and relations with fatigue, impairment and physical activity. Psychol Med. 2001 Jan;31(1):107-14. http://www.ncbi.nlm.nih.gov/pubmed/11200949

Strength and physiological response to exercise in patients with chronic fatigue syndrome

Abstract:

OBJECTIVE: To measure strength, aerobic exercise capacity and efficiency, and functional incapacity in patients with chronic fatigue syndrome(CFS) who do not have a current psychiatric disorder.

METHODS: Sixty six patients with CFS without a current psychiatric disorder, 30 healthy but sedentary controls, and 15 patients with a current major depressive disorder were recruited into the study. Exercise capacity and efficiency were assessed by monitoring peak and submaximal oxygen uptake, heart rate, blood lactate, duration of exercise, and perceived exertion during a treadmill walking test. Strength was measured using twitch interpolated voluntary isometric quadriceps contractions. Symptomatic measures included physical and mental fatigue, mood, sleep, somatic amplification, and functional incapacity.

RESULTS: Compared with sedentary controls, patients with CFS were physically weaker, had a significantly reduced exercise capacity, and perceived greater effort during exercise, but were equally unfit. Compared with depressed controls, patients with CFS had significantly higher submaximal oxygen uptakes during exercise, were weaker, and perceived greater physical fatigue and incapacity. Multiple regression models suggested that exercise incapacity in CFS was related to quadriceps muscle weakness, increased cardiovascular response to exercise, and body mass index. The best model of the increased exercise capacity found after graded exercise therapy consisted of a reduction in submaximal heart rate response to exercise.

CONCLUSIONS: Patients with CFS were weaker than sedentary and depressed controls and as unfit as sedentary controls. Low exercise capacity in patients with CFS was related to quadriceps muscle weakness, low physical fitness, and a high body mass ratio. Improved physical fitness after treatment was associated with increased exercise capacity. These data imply that physical deconditioning helps to maintain physical disability in CFS and that a treatment designed to reverse deconditioning helps to improve physical function.

Comment in: Chronic fatigue syndrome: is it physical? [J Neurol Neurosurg Psychiatry. 2000]

 

Source: Fulcher KY, White PD. Strength and physiological response to exercise in patients with chronic fatigue syndrome. J Neurol Neurosurg Psychiatry. 2000 Sep;69(3):302-7. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1737090/ (Full article)

 

Chronic fatigue syndrome: is it physical?

Comment on: Strength and physiological response to exercise in patients with chronic fatigue syndrome. [J Neurol Neurosurg Psychiatry. 2000]

 

It is increasingly recognised that chronic fatigue syndrome (CFS) is heterogeneous. A significant proportion of patients fulfilling operative criteria for a diagnosis of CFS will also fulfill criteria for a psychiatric disorder, such as depression or somatisation. Failure to recognise this heterogeneity prejudices attempts to understand CFS in cross sectional studies. In this issue (pp 302–307) Fulcher et al report a study of muscle strength, aerobic exercise capacity, and functional incapacity in a group of patients with CFS without concurrent psychiatric disorder, compared with patients with major depression and a group of normal but sedentary subjects.1 In an incremental treadmill exercise test, patients with CFS and depressed patients had lower peak oxygen consumption rates, maximal heart rates, and plasma lactate concentrations than the sedentary controls; but this reflected the shorter duration of exercise tolerated by these patients. At submaximal work rates, patients with CFS and depressed patients experienced greater perception of eVort than sedentary controls at the same level of work. This is in keeping with the finding that such patients show greater sensitivity to bodily sensations than normal subjects. Overall, there was little difference between the patients with CFS and the depressed patients in exercise characteristics, yet the patients with CFS reported significantly greater degrees of physical fatigue and physical incapacity.

You can read the full comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1737076/pdf/v069p00289.pdf

 

Source: Lane R. Chronic fatigue syndrome: is it physical? J Neurol Neurosurg Psychiatry. 2000 Sep;69(3):289. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1737076/

 

Significant other responses are associated with fatigue and functional status among patients with chronic fatigue syndrome

Abstract:

OBJECTIVE: The predictive power of partners’ responses to illness behavior for illness outcomes was investigated among couples in which one person had chronic fatigue syndrome (CFS).

METHODS: One hundred nineteen participants who met case-definition criteria for CFS and were living with a significant other (SO) completed self-report measures of relationship satisfaction, responses of their SO to fatigue symptoms, and outcome measures of fatigue and functional status.

RESULTS: The results indicated that more frequent solicitous SO responses to illness behavior were predictive of greater fatigue-related severity and bodily pain. Solicitous SO responses to fatigue behavior were particularly influential in the context of a satisfactory relationship. In highly satisfactory relationships, solicitous SO responses were associated with significantly greater fatigue severity and fatigue-related disability than in relationships characterized by low or average satisfaction.

CONCLUSIONS: Solicitous SO responses to CFS-related symptoms are associated with poorer patient outcomes, especially in the context of a satisfactory intimate relationship. Because of the cross-sectional nature of the study, the direction of effects cannot be interpreted unambiguously. SOs may be inadvertently positively reinforcing illness-related behavior: Solicitous partners may help the patient more with tasks of daily living, thereby decreasing the patient’s activity level, which may lead to deconditioning and disability. Alternatively, patients with more severe symptoms and disability may present more opportunities for concerned SO responses, which again may be heightened in the context of a caring, satisfactory relationship. In either case, the results suggest that additional research on the role of solicitous SO responses is warranted.

 

Source: Schmaling KB, Smith WR, Buchwald DS. Significant other responses are associated with fatigue and functional status among patients with chronic fatigue syndrome. Psychosom Med. 2000 May-Jun;62(3):444-50. http://www.ncbi.nlm.nih.gov/pubmed/10845358

 

Chronic fatigue syndrome: physical and cardiovascular deconditioning

Abstract:

We investigated whether chronic fatigue syndrome (CFS) patients have physical and/or cardiovascular de-conditioning, in 273 CFS patients and 72 healthy controls.

We used laboratory tests to assess haematological, biochemical, endocrinological and immunological systems. The cardiovascular system was assessed by echocardiography and carotid echography. Body composition was determined by dual energy X-ray absorptiometry (DEXA).

CFS patients had smaller left ventricular end systolic (p < 0.001) and diastolic (p = 0.008) dimensions but thinner posterior walls (p = 0.02) than corresponding values in healthy controls. Left ventricular mass was also reduced in CFS patients (p = 0.006). Both maximum (p < 0.001) and minimum (p < 0.008) diameter of the carotid artery were smaller in CFS patients. The laboratory screening tests showed significant differences in serum albumin (p = 0.05), phosphate (p = 0.02), HDL-cholesterol (p = 0.03), HDL:total cholesterol ratio (p = 0.01), triglycerides (p = 0.02), neutrophils (p = 0.01) and thyroid-stimulating hormone (p = 0.04) between CFS patients and controls. Male CFS patients had an increased percentage of fat mass compared with healthy male subjects (p = 0.02).

This large group of CFS patients had evidence of physical and cardiovascular de-conditioning, suggesting that in these patients a graded exercise programme could lead to physical reconditioning and could increase their ability to perform physical activities.

 

Source: De Lorenzo F, Xiao H, Mukherjee M, Harcup J, Suleiman S, Kadziola Z, Kakkar VV. Chronic fatigue syndrome: physical and cardiovascular deconditioning. QJM. 1998 Jul;91(7):475-81. http://qjmed.oxfordjournals.org/content/91/7/475.long (Full article)