Endothelial dysfunction in ME/CFS patients

Abstract:

Objective: A few earlier studies have found impaired endothelial function in patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). The present study investigated large-vessel and small-vessel endothelial function in patients with ME/CFS.

Study design: The study was a substudy of the RituxME trial, a national, multicenter, randomized, double-blind, placebo-controlled phase III study on the effect of rituximab vs. placebo in ME/CFS patients in Norway. Flow-mediated dilation (FMD) and post-occlusive reactive hyperemia (PORH) was measured at baseline and after 18 months of treatment in 39 patients and compared with healthy controls. Other outcome measures were symptom severity and various physical function measures.

Results: ME/CFS patients had markedly reduced FMD compared to healthy controls at baseline (5.1% vs. 8.2%, p< 0.0001, adjusted for arterial diameter and sex), and significantly lower microvascular regulation measured by PORH than healthy controls (1354 PU vs. 2208 PU, p = 0.002). There were no differences between the treatment and placebo groups in symptom changes or vascular measures. As a group, the ME/CSF patients experienced a slight, but significant improvement in clinical symptoms after 18 months. PORH, but not FMD, was similarly improved (1360 to 1834 PU, p = 0.028). There was no significant correlation between FMD and PORH. There were non-significant tendencies towards associations between symptom severity/physical function measures and lower FMD and PORH, and a significant correlation between PORH and steps per 24 hours at baseline.

Conclusions: ME/CFS patients had reduced macro- and microvascular endothelial function, indicating that vascular homeostasis may play a role in the clinical presentation of this disease.

Source: Sandvik MK, Sørland K, Leirgul E, Rekeland IG, Stavland CS, Mella O, Fluge Ø. Endothelial dysfunction in ME/CFS patients. PLoS One. 2023 Feb 2;18(2):e0280942. doi: 10.1371/journal.pone.0280942. PMID: 36730360; PMCID: PMC9894436. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9894436/ (Full text)

Detection of Epstein-Barr virus and cytomegalovirus in patients with chronic fatigue

Abstract:

Patients with chronic fatigue as a major complaint frequently present with recurrent sore throat, and on physical examination they have hyperemia and lymphoid hyperplasia of the pharyngeal area.

Pharyngeal scrapings were obtained from 41 such patients and analyzed for Epstein-Barr virus or cytomegalovirus DNA by colorimetric in situ hybridization. Results were compared with healthy control subjects matched for age and sex. Epstein-Barr virus-DNA was detected more frequently in male patients, 5/9 (55.6%), than controls, 0/6 (0%), but there was no difference in frequency in female patients, 4/32 (12.5%), than control subjects, 1/29 (3.4%).

Cytomegalovirus-DNA was detected infrequently in patients and controls, 13% versus 22% respectively. The presence of EBV-DNA did not correlate with antibody titers nor with the complaint of sore throat. Four of the five males who had positive EBV-DNA in the pharyngeal smears have now recovered.

 

Source: Wray BB, Gaughf C, Chandler FW Jr, Berry SS, Latham JE, Wood L, DuRant RH. Detection of Epstein-Barr virus and cytomegalovirus in patients with chronic fatigue. Ann Allergy. 1993 Sep;71(3):223-6. http://www.ncbi.nlm.nih.gov/pubmed/8396863