Haemodynamic differences amongst women who were screened for gestational diabetes in comparison to healthy controls.

AIM: To assess the changes in haemodynamics amongst pregnant women who were screened for gestational diabetes mellitus (GDM) in comparison to low-risk healthy pregnant controls. METHODOLOGY: A total of 120 pregnant women of mean (standard deviation) age 31.03 (5.41) years who attended their oral glucose tolerance test as part of the national screening for GDM (study), and 60 low-risk healthy pregnant women (control) of mean age 29.71 (5.33) years, were invited to participate in this study. All women included in the study booked at the University Hospitals of Leicester NHS Trust and fulfilled the relevant inclusion criteria. Non-invasive assessment of arterial stiffness and cardiac output were undertaken on participants between 26 and 28 weeks of pregnancy. The mean difference between GDM and low-risk group for each of the arterial stiffness and cardiac output measurements was assessed by a two-sample unpaired t-test. RESULTS: Significant differences were found between the study and control groups for brachial (-64.5 vs. -69.5, p < 0.04) and aortic augmentation indices (5.2 vs. 2.7, p = 0.04), though there was no significant difference for PWV (8.3 vs. 8.1, p = 0.49). Cardiac output (7.6 vs. 7.0, p = 0.011), stroke volume (84.4 vs. 76.9, p = 0.013) and central mean arterial pressure (71 vs. 58, <0.001) were also significantly different between groups. However, no significant differences were reported for heart rate, systolic and diastolic blood pressure, or total peripheral resistance. CONCLUSION: Pregnant women at risk of GDM between gestational weeks 26 and 28 had significantly increased measures of arterial stiffness, as assessed by brachial and aortic augmentation indices, compared with low-risk healthy controls. Whether these women are at greater long-term cardiovascular disease risk warrants further investigation.

The effects of metformin on maternal haemodynamics in gestational diabetes mellitus: A pilot study.

BACKGROUND: Gestational diabetes mellitus (GDM) is a major clinical challenge and is likely to remain so as the incidence of GDM continues to increase. AIM: To assess longitudinal changes in maternal haemodynamics amongst women diagnosed with GDM requiring either metformin or dietary intervention in comparison to low-risk healthy controls. METHODOLOGY: Fifty-six pregnant women attending their first appointment at the GDM clinic and 60 low-risk healthy pregnant controls attending their routine antenatal clinics were recruited and assigned to three groups: GDM Metformin (GDM-M), GDM Diet (GDM-D) and Control. Non-invasive assessment of maternal haemodynamics, using recognised measures of arterial stiffness and central blood pressure (Arteriograph®), were undertaken under controlled conditions within four gestational windows: antenatal; AN1 (26-28 weeks), AN2 (32-34 weeks) and AN3 (37-40 weeks), and postnatal (PN) (6-8 weeks after delivery). Data were analysed using a linear mixed model incorporating gestational age and other relevant predictors, including age, blood pressure (BP), baseline bodyweight and pulse as fixed effects, and patient as a random effect. RESULTS: Fitted linear mixed models showed evidence of a two-way interaction effect between groups (GDM-D, GDM-M and Control) and stages of gestation (AN1, AN2, AN3 and PN) for maternal haemodynamic parameters: brachial artery augmentation index (AIx) (p = 0.004), aortic AIx (p = 0.008), and central systolic BP (p = 0.001). However, differences in respect of aortic pulse wave velocity (p = 0.001) and heart rate (p < 0.001) were only significant for gestational stage. At AN2, we did not observe any evidence that the mean brachial Aix in the GDM-M was different from the control group (p = 0.158). CONCLUSION: AIx and central systolic BP measures of arterial stiffness are adversely affected by GDM in comparison to controls during pregnancy. The possible beneficial effects of metformin therapy seen at 32 to 34 weeks of gestation require further exploration.

Association between arterial stiffness and wave reflection with subsequent development of placental-mediated diseases during pregnancy: findings of a systematic review and meta-analysis.

OBJECTIVE: We present a comprehensive systematic review of published literature to examine, whether arterial stiffness and wave reflection measurements during pregnancy differed between healthy patients and patients with placental-mediated diseases including preeclampsia (PET), small for gestational age (SGA), fetal death, and placental abruption, and a quantitative assessment of the findings using the meta-analysis approach. METHODS: We searched Medline, Embase, and The Cochrane Library for studies of arterial stiffness in pregnancy, analyzed pregnancy outcomes and conducted the meta-analysis of data evaluated by trimesters of pregnancy. Hemodynamic parameters evaluated included: pulse wave velocity (PWV), augmentation index (AIx), and augmentation index-75 (AIx-75). RESULTS: We screened 2806 citations, reviewed 36 studies and included nine (n = 15 923) studies for further quantitative assessment. Compared with healthy pregnancy, measures of arterial stiffness and wave reflection were consistently increased among pregnant women who subsequently developed PET during all trimesters. In the first trimester, mean AIx-75 (%) in the PET group was significantly higher with estimated standardized mean difference (SMD) of 0.90 [95% confidence intervals (95% CI) 0.07-1.73; P = 0.034]. In the second trimester, the PET group had significantly higher PWV (m/s) with estimated SMD of 1.26 (95% CI 0.22-2.30; P = 0.018). Concerning the SGA group, mean AIx (%) was greater during the second trimester only: 65.5 (SD 15.6) vs. 57.0 (11.2), P < 0.01. CONCLUSION: There is significant increase in arterial stiffness and wave reflection parameters among pregnant women who subsequently developed PET and SGA fetuses. Larger studies with consistent methodological designs are required to evaluate the role and usefulness of arterial stiffness and wave reflection measurements as a screening tool for placental-mediated diseases during pregnancy.

Longitudinal study to assess changes in arterial stiffness and cardiac output parameters among low-risk pregnant women.

AIM: A single-centre, prospective longitudinal study to assess changes in maternal arterial stiffness and cardiac output parameters among low-risk healthy pregnant women. METHODOLOGY: Thirty low-risk, healthy, pregnant women attending their routine antenatal dating ultrasound scan were recruited. Non-invasive assessment of arterial stiffness and cardiac output was undertaken at five gestational windows from 11 to 40 weeks of pregnancy. Data were analysed using a linear mixed model incorporating time and other relevant predictors as fixed effects, and patient as a random effect. RESULTS: Gestational age had a significant effect on all arterial stiffness parameters, including brachial augmentation index (AIx) (p = .001), aortic AIx (p = .002) and aortic pulse wave velocity (p = .002). The aortic AIx (%) reduced during pregnancy: the lowest mean (standard error, SE) was 4.07 (1.01) at 28 weeks before it increased to 7.04 (SE 1.64) at 40 weeks. Similarly, non-invasive assessments of cardiac output (p < .001), stroke volume (p = .014), heart rate (p < .001) and total peripheral resistance (p < .001) demonstrated significant changes with gestational age. Mean cardiac output (l/m) increased during pregnancy reaching a peak at 28 weeks gestation 6.66 (SE 0.28), but dropped thereafter to reach 5.71 (SE 0.25) around term. CONCLUSION: The current study provides pregnancy normograms for gestational changes in arterial stiffness and cardiac output parameters among low-risk, healthy pregnant women. Further work will be required to assess the risk of placental mediated diseases and pregnancy outcome among pregnant women with parameters outside the normal range.