biostudies-literatureSandvik MKThe Norwegian Ministry of Health and Care ServicesThe Norwegian Research CouncilKavli TrustThe Norwegian ME associationThe Norwegian Regional Health TrustsMEandYou Foundatione0280942https://www.ebi.ac.uk/biostudies/studies/S-EPMC9894436biostudies-literatureUnknown18(2)<h4>Objective</h4>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.<h4>Study design</h4>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.<h4>Results</h4>ME/CFS patients had markedly PloS oneEndothelial dysfunction in ME/CFS patients.PMC9894436229035/H10Leirgul ESorland KMella OStavland CSSandvik MKRekeland IGFluge OfalseEndothelial dysfunction in ME/CFS patients.<h4>Objective</h4>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.<h4>Study design</h4>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.<h4>Results</h4>ME/CFS patients had markedly 2023-01-01T00:00:00Z20232026-05-28T19:00:18.873Z2025-02-19T00:13:27.87ZS-EPMC98944363673036010.1371/journal.pone.0280942