Shear rate patterns during flow-mediated dilation in women with endometriosis: preliminary findings

• Published in: Physiology (Bethesda, Md.) Md.), 2023-05, Vol.38 (S1)
• Main Authors: Kirby, Nathalie, Williams, Auni, Content, Virginia, Wolf, S Tony, Dillon, Gabrielle, Stachenfeld, Nina, Alexander, Lacy
• Format: Article
• Language: English
• ISSN: 1548-9213; 1548-9221
• DOI: 10.1152/physiol.2023.38.S1.5733199

Abstract only Purpose: Endometriosis is an estrogen-dependent gynecological disorder associated with systemic inflammation and arterial stiffness, which may negatively modulate shear stress patterns to promote a pro-atherogenic state, and thus contribute to the elevated cardiovascular disease risk observed in women with the disease. However, shear stress patterns have not previously been examined in this population. Therefore, the purpose of this study was to investigate whether arterial blood flow patterns are altered in women with endometriosis. We hypothesized that women with endometriosis would exhibit disturbed blood flow patterns, characterized by high retrograde shear rates and oscillatory flow as well as reduced anterograde shear rates, as compared with women without the disease. Methods: We examined anterograde and retrograde shear rates, and oscillatory shear index (OSI; |retrograde shear rate|÷[|antegrade shear rate|+|retrograde shear rate|]) in four women with surgically confirmed endometriosis and eight without (mean (SD), 28 (5) years, BMI 24.7 (4.2) kg·m -2 ) at rest, during hyperemia (60 s post-forearm occlusion at 220 mmHg) and recovery (120-180 s post-occlusion) from flow-mediated dilation using duplex Doppler ultrasound. Shear rates were compared using two-factor (group x phase) linear mixed-effects models with post-hoc corrections for multiple comparisons of three time-points. Results: Endometriosis patients exhibited greater OSI (interaction: p=0.001) at rest (mean difference [95%CI]; 0.095 [0.001, 0.188], p=0.033) and recovery (0.126 [0.034, 0.226], p=0.005), though not during hyperemia ( p>0.999) compared to controls. This was driven by greater retrograde shear (interaction: p=0.013) during recovery (15 sec -1 [2, 28], p=0.002), though retrograde shear did not differ between groups at rest ( p=0.155) or during hyperemia ( p>0.999). Anterograde shear (interaction: p=0.049) was greater in controls than in endometriosis patients during hyperemia (276 sec -1 [61, 613], p=0.026), but not during rest or recovery (both p>0.999). Conclusions: Women with endometriosis exhibited greater oscillatory shear at rest and greater oscillatory and retrograde shear during recovery from flow-mediated dilation, as compared to controls. However, anterograde shear was diminished in endometriosis patients during hyperemia. These data indicate that shear stress patterns are negatively altered in women with endometriosis, which provides novel mechanistic insi