Value of adding second-trimester uterine artery Doppler to patient characteristics in identification of nulliparous women at increased risk for pre-eclampsia: an individual patient data meta-analysis.

OBJECTIVE: To investigate the value of adding second-trimester uterine artery Doppler ultrasound to patient characteristics in the identification of nulliparous women at risk for pre-eclampsia. METHODS: For this individual patient data meta-analysis, studies published between January 1995 and December 2009 were identified in MEDLINE and EMBASE. Studies were eligible in which Doppler assessment of the uterine arteries had been performed among pregnant women and in which gestational age at ultrasound, Doppler ultrasound findings and data on the occurrence of pre-eclampsia were available. We invited corresponding authors to share their original datasets. Data were included of nulliparous women who had had a second-trimester uterine artery Doppler ultrasound examination. Shared data were checked for consistency, recoded to acquire uniformity and merged into a single dataset. We constructed random intercept logistic regression models for each of the patient and Doppler characteristics in isolation and for combinations. We compared goodness of fit, discrimination and calibration. RESULTS: We analyzed eight datasets, reporting on 6708 nulliparous women, of whom 302 (4.5%) developed pre-eclampsia. Doppler findings included higher, lower and mean pulsatility index (PI) and resistance index (RI) and any or bilateral notching. Of these, the best predictors were combinations of mean PI or RI and bilateral notching, with areas under the receiver-operating characteristics curve (AUC) of 0.75 (95% confidence interval (CI), 0.56-0.95) and 0.70 (95% CI, 0.66-0.74), respectively. Addition of Doppler findings to the patient characteristics blood pressure or body mass index (BMI) significantly improved discrimination. A model with blood pressure, PI and bilateral notching had an AUC of 0.85 (95% CI, 0.67-1.00). CONCLUSIONS: The addition of Doppler characteristics of mean PI or RI and bilateral notching to patient characteristics of blood pressure or BMI improves the identification of nulliparous women at risk for pre-eclampsia.

Is psychosocial stress in first ongoing pregnancies associated with pre-eclampsia and gestational hypertension?

OBJECTIVE: Investigating the association of pre-eclampsia and gestational hypertension with psychosocial stress in the first half of pregnancy. DESIGN: Prospective community-based cohort study. SETTING: Amsterdam, The Netherlands. POPULATION: Between January 2003 and March 2004, all pregnant Amsterdam women (n = 12 377) were invited to fill in a questionnaire with sociodemographic and psychosocial variables (response rate 67%). Only nulliparous women with a singleton pregnancy, who completed the questionnaire before 24 weeks, and delivered after 24 weeks, were included. METHODS: A postpartum questionnaire was used to gather information on hypertension or proteinuria. If this questionnaire was not available, the national obstetric register was used for pregnancy outcome. Medical files were examined for women with hypertension and/or proteinuria to confirm the diagnosis of pre-eclampsia and gestational hypertension according to the International Society for the Study of Hypertension in Pregnancy guidelines. Psychosocial stress was defined as workstress (Work Experience and Appreciation Questionnaire partly based on the Job Content Instrument of Karasek et al.), anxiety (the State-Trait Anxiety Inventory), depression (Center for Epidemiological Studies Depression Scale) and pregnancy-related anxiety (PRAQ-R). The association of psychosocial stress with the incidence of pre-eclampsia and gestational hypertension was explored by multivariate analysis adjusted for sociodemographic and medical confounders. MAIN OUTCOME MEASURES: Incidence of pre-eclampsia and gestational hypertension. RESULTS: A total of 3679 women were included. The incidence of pre-eclampsia and gestational hypertension was 3.5 and 4.4%, respectively. Workstress, anxiety, pregnancy-related anxiety or depression had no effect on the incidence of pre-eclampsia or gestational hypertension. CONCLUSION: Psychosocial stress in the first half of pregnancy does not influence the incidence of pre-eclampsia and gestational hypertension in nulliparous women.

Comparison of OPS imaging and conventional capillary microscopy to study the human microcirculation.

Orthogonal polarization spectral (OPS) imaging is a new clinical technique for observation of the microcirculation of organ surfaces. For validation purposes, we compared OPS images of the nailfold skin with those obtained from conventional capillary microscopy at rest and during venous occlusion in 10 male volunteers. These images were computer analyzed to provide red blood cell velocity and capillary diameters of the same nailfold capillaries at rest and during venous occlusion. Results showed that OPS images provided similar values for red blood cell velocity and capillary diameter as those obtained from capillary microscopy images. OPS imaging, however, provided significantly better image quality, as shown by comparison of image contrast between OPS imaging and capillary microscopy. This made image analysis better and easier to perform. It is anticipated, therefore, that OPS imaging will become a new and powerful technique in the study of the human microcirculation in vivo because it can be used on human internal organs.

Impaired vascular function in women with pre-eclampsia observed with orthogonal polarisation spectral imaging.

OBJECTIVE: To investigate in vivo the function of the microcirculation of the skin in pregnancy and pregnancy complicated with pre-eclampsia. DESIGN: Case-control study. SETTING: Academic Medical Centre. PARTICIPANTS: A group of 10 women with pre-eclampsia and a healthy control group of 10 pregnant women. METHODS: The microcirculation of the skin of the finger at rest and during venous occlusion was studied with laser Doppler fluxmetry and orthogonal polarisation spectral imaging. By inflating a cuff around the upper arm to a pressure of 50 mmHg, causing venous occlusion, the local sympathetic veno-arteriolar reflex was provoked. With laser Doppler fluxmetry the blood flow of the skin at a depth of 1-2mm was measured at rest and during venous occlusion. Orthogonal polarisation spectral imaging was used to assess red blood cell velocity at rest and during venous occlusion of the nutritive capillaries of the skin. RESULTS: Laser Doppler fluxmetry showed no significant difference between the normotensive group and the group with pre-eclampsia. Using orthogonal polarisation spectral imaging, venous occlusion produced a significantly greater decrease in red blood cell velocity in the control group than in the women with pre-eclampsia: (84% (81-88)(median and interquartile range) vs 58% (45-88), P = 0.0029). No differences in absolute red blood cell velocities were observed between groups either at rest or during venous occlusion. CONCLUSION: This study shows an impaired local veno-arteriolar reflex in pre-eclampsia at the nutritive, but not at the therrmoregulatory, level of the microcirculation of the skin.