Background: The aim of this study was to examine endothelium function and seasonal variations of endothelium function in women with primary Raynaud's phenomenon (RP) and healthy controls.
Patients and methods: After a fast of at least 8 hours we studied 21 patients with primary RP (mean age 31.1 years, mean duration of RP 9.1 years) and 22 controls (mean age 27.8 years) by use of high resolution brachial artery sonography in winter (December/January 2000) and summer (July/August 2001). To exclude circadian variations all examinations were performed in the late afternoon only. All subjects were non-smokers. Confounding factors like serum glucose, HbAlc, and lipid concentrations were analyzed immediately before the investigations. Nicotine contamination was randomly analyzed in hair samples in 8 subjects of each study group. Flow mediated dilatation (FMD%) and nitroglycerin induced dilatation (NID%) were calculated by putting the basal vessel diameter as 100%.
Results: Basal, flow-mediated, and nitroglycerin-induced absolute diameters of the brachial artery did not differ significantly between the study groups (p = 0.85). The test conditions (basal, postocclusive, nitroglycerin-induced) always let to the same vessel response in winter and summer (p = 0.61) and there was no significant influence between these test conditions and the study groups (p = 0.07). Compared to patients FMD% was slightly reduced in controls in summer (p = 0.09). Analysis of variance excluded a significant relation between study group and season (p = 0.43). For NID% too, no statistically significant differences were found.
Conclusions: We were not able to show impaired or seasonally variant flow-mediated or nitroglycerin-induced dilatation of the brachial artery in patients with primary RP. Our results argue against the presence of a more generalized endothelium dysfunction detectable with high resolution ultrasound of the brachial artery in patients with primary RP.