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Laser Doppler: A Tool for Measuring Pancreatic Islet Microvascular Vasomotion In Vivo
Published on: March 8, 2018
Effect of circadian rhythm on doppler parameters ın patients with gestational diabetes mellitus
Ezgi Darici1,2, Burak Guler3, Enis Ozkaya4
1Department of Obstetrics and Gynecology, Center for Endometriosis, Semmelweis University Budapest, Hungary. ezgidarici@hotmail.com.
Objectives:
Circadian rhythm (CR) is a 24-hour biological cycle regulated by endogenous and environmental factors. Altered CR gene expression has been associated with gestational diabetes mellitus (GDM), potentially affecting vascular regulation and fetal hemodynamics. This study aimed to evaluate the effect of circadian rhythm on Doppler ultrasonographic parameters in pregnancies complicated by GDM.
Material And Methods:
This prospective cross-sectional study included 80 pregnant women between 32-39 gestational weeks classified into control, diet-regulated GDM, and insulin-regulated GDM groups. Doppler measurements of the umbilical artery (UA), middle cerebral artery (MCA), and uterine arteries (UtA) were performed twice daily at sunrise and sunset. Peak systolic velocity (PSV), systole/diastole ratio (S/D), pulsatility index (PI), and resistance index (RI) were analyzed.
Results:
In the control group, MCA S/D and PI demonstrated significant diurnal variation (p = 0.03 and p = 0.01, respectively). In insulin-regulated GDM, MCA PI showed significant variation between morning and evening measurements (p = 0.006), whereas MCA PSV, S/D, and RI remained unchanged (p > 0.05). Right uterine artery S/D, PI, and RI values also differed significantly in insulin-regulated GDM (p = 0.014, p = 0.008, and p = 0.001, respectively). No significant variation was detected in the diet-regulated GDM group or in umbilical and left uterine artery Doppler parameters. Intraclass correlation coefficient analysis demonstrated moderate-to-good reproducibility for MCA and UA measurements and very good reliability for uterine artery S/D, PI, and RI indices.
Discussion:
The findings suggest that circadian rhythm influences Doppler parameters, particularly in insulin-regulated GDM pregnancies. These results are consistent with previous studies demonstrating vascular and metabolic alterations in GDM.
Conclusions:
Doppler parameters vary during the day, reflecting circadian influence, especially in insulin-regulated GDM.
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