[Note: Arterial wave reflection is an indicator of arterial stiffness.]
Some of the symptoms reported by people with Chronic Fatigue Syndrome (CFS) are associated with various cardiovascular phenomena. Markers of cardiovascular risk, including inflammation and oxidative stress, have been demonstrated in some CFS patients but little is known about the relationship of these and prognostic indicators of cardiovascular risk in this patient group.
We sought to investigate the relationship between inflammation and oxidative stress and augmentation index, a measure of arterial stiffness, in 41 well characterized CFS patients and in 30 healthy subjects.
The augmentation index, normalized for a heart rate of 75 beats per minute (AIx@75), was significantly greater in CFS patients than in control subjects (22.5 +/- 1.7 versus 13.3 +/- 2.3%, P=0.002). CFS patients also had significantly increased levels of C-reactive protein (2.58 +/- 2.91 versus 1.07 +/- 2.16 g/mL, P<0.01) and 8-iso-prostaglandin F 2alpha isoprostanes (470.7 +/- 250.9 versus
331.1 +/- 97.6 pg/mL, P<0.005).
In CFS patients, AIx@75 significantly correlated with log C-reactive protein (r=0.507, P=0.001), isoprostanes (r=0.366, P=0.026), oxidized LDL (r=0.333, P=0.039) and systolic blood pressure (r=0.371, P=0.017).
In a stepwise multiple regression model, (including systolic and diastolic blood pressure, body mass index, C-reactive protein, TNFalpha, IL-1, oxidised LDL, HDL cholesterol levels, isoprostanes, age and gender), AIx@75 was independently associated with log CRP (beta=0.385, P=0.006), age (beta=0.363, P=0.022), and female gender (beta=0.302, P=0.03) in CFS patients.
The combination of increased arterial wave reflection, inflammation and oxidative stress may result in an increased risk of future cardiovascular events. Assessment of arterial wave reflection might be useful for determining cardiovascular risk in this patient group.
Source: Clinical Science (London) Nov 21 2007; [E-pub ahead of print] PMID: 18031285, by Spence VA, Kennedy G, Belch JJ, Hill A, Khan F. Institute of Cardiovascular Research, University of Dundee Medical School, Dundee, Scotland, UK.