Elevated blood lactate in resting conditions correlate with post-exertional malaise severity in patients with Myalgic encephalomyelitis/Chronic fatigue syndrome

Abstract

Elevated blood lactate after moderate exercise was reported in some of patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). We hypothesised that blood lactate could be also elevated in resting conditions. We aimed investigating the frequency of elevated lactate at rest in ME/CFS patients, and comparing characteristics of ME/CFS patients with and without elevated lactate. Patients fulfilling international consensus criteria for ME/CFS who attended the internal medicine department of University hospital Angers-France between October 2011 and December 2017 were included retrospectively. All patients were systematically hospitalised for an aetiological workup and overall assessment. We reviewed their medical records for data related to the assessment: clinical characteristics, comorbidities, fatigue features, post-exertional malaise (PEM) severity, and results of 8 lactate measurements at rest. Patients having ≥1 lactate measurement ≥2 mmol/L defined elevated lactate group. The study included 123 patients. Elevated (n = 55; 44.7%) and normal (n = 68; 55.3%) lactate groups were comparable except for PEM, which was more severe in the elevated lactate group after adjusting for age at disease onset, sex, and comorbidities (OR 2.47, 95% CI: 1.10–5.55). ME/CFS patients with elevated blood lactate at rest may be at higher risk for more severe PEM. This finding may be of interest in ME/CFS management.

Cellular metabolism dictates T cell effector function in health and disease

“…Interestingly, in non‐confined tissues elevated levels of lactate are reported in the serum of MS patients. In these patients, increased levels of lactate correlates with fatigue and exercise intolerance 126 …”

“…In these patients, increased levels of lactate correlates with fatigue and exercise intolerance. 126 In synovitis of RA patients, the inflammatory infiltrate contains mostly monocyte and/or MΦ grouped in follicular structures. Synovitis also harbours confined secondary lymphoid organs (SLO) like features.…”

Pathophysiology of skeletal muscle disturbances in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

“…Does this lead to a situation of anaerobic glycolysis even at rest? To be more specific, ME/CFS patients do not only show elevated lactate levels after exercise; a recent paper shows that a group of ME/CFS patients (about half) has already elevated lactate levels at rest and these correlate with PEM [ 79 ]. During exercise blood flow to skeletal muscle can increase 20 to 30-fold reflecting the high metabolism during exercise.…”

Epidemiological and clinical factors associated with post-exertional malaise severity in patients with myalgic encephalomyelitis/chronic fatigue syndrome

“…ME/ CFS patients with comorbid IBS may constitute a distinct ME/CFS subgroup, characterized by more severe fatigue and GI symptoms [44]. Dysbiosis could thus trigger autoimmunity, which in turn might be responsible for mitochondrial dysfunction identified as having a role not only in PEM pathophysiology [12,13], but also in terms of PEM severity as we have recently demonstrated [14].…”

“…However some studies showed that mitochondrial dysfunction may have a role in PEM nature [12,13]. We recently reported that elevated blood lactate levels at rest in a subgroup of ME/CFS patients were associated with more severe PEM [14].…”