Emerging concepts of shear stress in placental development and function

Blood flow, and the force it generates, is critical to placental development and function throughout pregnancy. This mechanical stimulation of cells by the friction generated from flow is called shear stress (SS) and is a fundamental determinant of vascular homeostasis, regulating remodelling and vasomotor tone. This review describes how SS is fundamental to the establishment and regulation of the blood flow through the uteroplacental and fetoplacental circulations. Amongst the most recent findings is that alongside the endothelium, embryonic stem cells and the villous trophoblast are mechanically sensitive. A complex balance of forces is required to enable effective establishment of the uteroplacental circulation, while protecting the embryo and placental villi. SS also generates flow-mediated vasodilatation through the release of endothelial nitric oxide, a process vital for adequate placental blood flow. The identification of SS sensors and the mechanisms governing how the force is converted into biochemical signals is a fast-paced area of research, with multiple cellular components under investigation. For example, the Piezo1 ion channel is mechanosensitive in a variety of tissues including the fetoplacental endothelium. Enhanced Piezo1 activity has been demonstrated in response to the Yoda1 agonist molecule, suggesting the possibility for developing tools to manipulate these channels. Whether such agents might progress to novel therapeutics to improve blood flow through the placenta requires further consideration and research.

Piezo1 channels are mechanosensors in human fetoplacental endothelial cells

STUDY QUESTION

Does the shear stress sensing ion channel subunit Piezo1 have an important mechanotransduction role in human fetoplacental endothelium?

SUMMARY ANSWER

Piezo1 is present and functionally active in human fetoplacental endothelial cells, and disruption of Piezo1 prevents the normal response to shear stress.

WHAT IS KNOWN ALREADY

Shear stress is an important stimulus for maturation and function of placental vasculature but the molecular mechanisms by which the force is detected and transduced are unclear. Piezo1 channels are Ca²⁺-permeable non-selective cationic channels which are critical for shear stress sensing and maturation of murine embryonic vasculature.

STUDY DESIGN, SAMPLES/MATERIALS, METHODS

We investigated the relevance of Piezo1 to placental vasculature by studying human fetoplacental endothelial cells (FpECs) from healthy pregnancies. Endothelial cells were isolated from placental cotyledons and cultured, for the study of tube formation and cell alignment to shear stress. In addition, human placental arterial endothelial cells were isolated and studied immediately by patch-clamp electrophysiology.

MAIN RESULTS AND THE ROLE OF CHANCE

The synthetic Piezo1 channel agonist Yoda1 caused strong elevation of the intracellular Ca²⁺ concentration with a 50% effect occurring at about 5.4 μM. Knockdown of Piezo1 by RNA interference suppressed the Yoda1 response, consistent with it being mediated by Piezo1 channels. Alignment of cells to the direction of shear stress was also suppressed by Piezo1 knockdown without loss of cell viability. Patch-clamp recordings from freshly isolated endothelium showed shear stress-activated single channels which were characteristic of Piezo1.

LIMITATIONS, REASONS FOR CAUTION

The in vitro nature of fetoplacental endothelial cell isolation and subsequent culture may affect FpEC characteristics and PIEZO1 expression. In addition to Piezo1, alternative shear stress sensing mechanisms have been suggested in other systems and might also contribute in the placenta.

WIDER IMPLICATIONS OF THE FINDINGS

These data suggest that Piezo1 is an important molecular determinant of blood flow sensitivity in the placenta. Establishing and manipulating the molecular mechanisms regulating shear stress sensing could lead to novel therapeutic strategies to improve blood flow in the placenta.

LARGE-SCALE DATA

Not applicable.

STUDY FUNDING/COMPETING INTEREST(S)

LCM was funded by a Clinical Research Training Fellowship from the Medical Research Council and by the Royal College of Obstetricians and Gynaecologists, and has received support from a Wellcome Trust Institutional Strategic Support Fund. JS was supported by the Wellcome Trust and a BHF Intermediate Research Fellowship. HJG, CW, AJH and PJW were supported by PhD Studentships from BHF, BBSRC and the Leeds Teaching Hospitals Charitable Foundation respectively. All authors declare no conflict of interest.

Metabolic syndrome and time to pregnancy: a retrospective study of nulliparous women

OBJECTIVE

To determine: (1) the association between metabolic syndrome (MetS), time to pregnancy (TTP), and infertility; (2) associations between individual and an increasing number of MetS components, TTP, and infertility; and (3) whether these relationships differ by body mass index (BMI < 30 kg/m² versus BMI ≥ 30 kg/m² ).

DESIGN

Retrospective cohort study.

SETTING

Multiple centres (in Australia, Ireland, New Zealand, and the UK).

POPULATION

Five thousand five hundred and nineteen low-risk nulliparous pregnant women.

METHODS

Data on retrospectively reported TTP (number of months to conceive) and a blood sample to assess metabolic health were collected between 14 and 16 weeks of gestation. MetS was defined according to the International Diabetes Federation criteria. Accelerated failure time models with log-normal distribution were conducted to estimate time ratios (TRs) and 95% CIs. Differences in MetS on infertility (TTP > 12 months) were compared using a generalised linear model (Poisson distribution) with robust variance estimates (relative risks, RRs; 95% CIs). All analyses (entire cohort and split by BMI) were controlled for a range of maternal and paternal confounding factors.

MAIN OUTCOME MEASURES

Time to pregnancy and infertility.

RESULTS

Of the 5519 women included, 12.4% (n = 684) had MetS. Compared with women without MetS, women with MetS had a longer TTP (adjusted TR 1.30; 95% CI 1.15-1.46), which was similar in women who were obese and in women who were not obese. Marginal estimates for median TTP in women with MetS versus without MetS was 3.1 months (3.0-3.3 months) versus 4.1 months (3.6-4.5 months), respectively. Women with MetS were at a 62% greater risk for infertility and were at a greater risk for infertility whether they were obese (adjusted RR 1.62; 95% CI 1.15-2.29) or not (adjusted RR 1.73; 95% CI 1.33-2.23). Reduced high-density lipoprotein cholesterol (HDL-C) and raised triglycerides (TGs) were the main individual components associated with risk for infertility.

CONCLUSION

Metabolic syndrome is associated with longer TTP and infertility, independent of obesity. Additional studies, before pregnancy, are required to support our findings and to determine the applicability of which combinations of metabolic abnormalities pose the greatest risk to delayed fertility, or whether individual components are amenable to modification.

TWEETABLE ABSTRACT

Metabolic syndrome is associated with longer time to pregnancy and infertility, independent of obesity.

Rapid intra-adrenal feedback regulation of glucocorticoid synthesis

The hypothalamic–pituitary–adrenal axis is a vital neuroendocrine system that regulates the secretion of glucocorticoid hormones from the adrenal glands. This system is characterized by a dynamic ultradian hormonal oscillation, and in addition is highly responsive to stressful stimuli. We have recently shown that a primary mechanism generating this ultradian rhythm is a systems-level interaction where adrenocorticotrophin hormone (ACTH) released from the pituitary stimulates the secretion of adrenal glucocorticoids, which in turn feedback at the level of the pituitary to rapidly inhibit ACTH secretion. In this study, we combine experimental physiology and mathematical modelling to investigate intra-adrenal mechanisms regulating glucocorticoid synthesis. Our modelling results suggest that glucocorticoids can inhibit their own synthesis through a very rapid (within minutes), presumably non-genomic, intra-adrenal pathway. We present further evidence for the existence of a short time delay in this intra-adrenal inhibition, and also that at the initiation of each ACTH stimulus, this local feedback mechanism is rapidly antagonized, presumably via activation of the specific ACTH receptor (MC2R) signalling pathway. This mechanism of intra-adrenal inhibition enables the gland to rapidly release glucocorticoids while at the same time preventing uncontrolled release of glucocorticoids in response to large surges in ACTH associated with stress.

Previous pregnancy loss has an adverse impact on distress and behaviour in subsequent pregnancy

OBJECTIVE

To investigate whether women with previous miscarriages or terminations have higher levels of anxiety, depression, stress, and altered behaviours in a subsequent pregnancy.

DESIGN

A retrospective analysis of 5575 women recruited into the Screening for Pregnancy Endpoints (SCOPE) study, a prospective cohort study.

SETTING

Auckland, New Zealand, Adelaide, Australia, Cork, Ireland, and Manchester, Leeds, and London, UK.

POPULATION

Healthy nulliparous women with singleton pregnancies.

METHODS

Outcomes were recorded at 15 and 20 weeks of gestation.

MAIN OUTCOME MEASURES

Short-form State-Trait Anxiety Inventory (STAI) score, Perceived Stress Scale score, Edinburgh Postnatal Depression Scale score, and pregnancy-related behaviour measured using behavioural responses to pregnancy score.

RESULTS

Of the 5465 women included in the final analysis, 559 (10%) had one and 94 (2%) had two previous miscarriages, and 415 (8%) had one and 66 (1%) had two previous terminations of pregnancy. Women with one previous miscarriage had increased anxiety (adjusted mean difference 1.85; 95% confidence interval, 95% CI 0.61-3.09), perceived stress (adjusted mean difference 0.76; 95% CI 0.48-1.03), depression (adjusted odds ratio, aOR 1.26; 95% CI 1.08-1.45), and limiting/resting behaviour in pregnancy (adjusted mean difference 0.80; 95% CI 0.62-0.97). In women with two miscarriages, depression was more common (aOR 1.65; 95% CI 1.01-2.70) and they had higher scores for limiting/resting behaviour in pregnancy (adjusted mean difference 1.70; 95% CI 0.90-2.53) at 15 weeks of gestation. Women with one previous termination displayed elevated perceived stress (adjusted mean difference 0.65; 95% CI 0.08-1.23) and depression (aOR 1.25; 95% 1.08-1.45) at 15 weeks of gestation. Women with two previous terminations displayed increased perceived stress (adjusted mean difference 1.43; 95% CI 0.00-2.87) and depression (aOR 1.67; 95% 1.28-2.18).

CONCLUSIONS

This study highlights the psychological implications of miscarriage and termination of pregnancy.

Second-trimester maternal distress increases the risk of small for gestational age

BACKGROUND

The effect of prenatal distress on the risk of a small for gestational age (SGA) infant is uncertain. We have addressed the influences of prenatal stress, anxiety and depression on the risk of SGA. We also examined the effects of infant sex and timing of distress during pregnancy on any observed associations.

METHOD

The study population comprised 5606 healthy nulliparous pregnant women who participated in the international prospective Screening for Obstetric and Pregnancy Endpoints (SCOPE) study. Women completed the Perceived Stress Scale (PSS), the short form of the Spielberger State-Trait Anxiety Inventory (STAI) and the Edinburgh Postnatal Depression Scale (EPDS) at 15 ± 1 and 20 ± 1 weeks' gestation. SGA was defined as birthweight below the 10th customized percentile. Logistic regression was used for data analysis, adjusting for several potential confounders such as maternal age, body mass index (BMI), smoking, socio-economic status and physical exercise.

RESULTS

The risk of SGA was increased in relation to mild [adjusted odds ratio (aOR) 1.35, 95% confidence interval (CI) 1.07-1.71], moderate (aOR 1.26, 95% CI 1.06-1.49), high (aOR 1.45, 95% CI 1.08-1.95) and very high stress scores (aOR 1.56, 95% CI 1.03-2.37); very high anxiety score (aOR 1.45, 95% CI 1.13-1.86); and very high depression score (aOR 1.14, 95% CI 1.05-1.24) at 20 ± 1 weeks' gestation. Sensitivity analyses showed that very high anxiety and very high depression increases the risk of SGA in males but not in females whereas stress increases the risk of SGA in both males and females.

CONCLUSIONS

These findings suggest that prenatal stress, anxiety and depression measured at 20 weeks' gestation increase the risk of SGA. The effects of maternal anxiety and depression on SGA were strongest in male infants.

Type 2 diabetes, socioeconomic status and risk of cancer in Scotland 2001-2007

AIMS/HYPOTHESIS

The objective of this study was to use Scottish national data to assess the influence of type 2 diabetes on the risk of cancer at 16 different sites, while specifically investigating the role of confounding by socioeconomic status in the diabetes-cancer relationship.

METHODS

All people in Scotland aged 55-79 years diagnosed with any of the cancers of interest during the period 2001-2007 were identified and classified by the presence/absence of co-morbid type 2 diabetes. The influence of diabetes on cancer risk for each site was assessed via Poisson regression, initially with adjustment for age only, then adjusted for both age and socioeconomic status.

RESULTS

There were 4,285 incident cancers in people with type 2 diabetes. RR for any cancers (adjusted for age only) was 1.11 (95% CI 1.05, 1.17) for men and 1.33 (1.28, 1.40) for women. Corresponding values after additional adjustment for socioeconomic status were 1.10 (1.04, 1.15) and 1.31 (1.25, 1.38), respectively. RRs for individual cancer sites varied markedly.

CONCLUSIONS/INTERPRETATION

Socioeconomic status was found to have little influence on the association between type 2 diabetes and cancer.

Cause-specific mortality in Scottish patients with colorectal cancer with and without type 2 diabetes (2000-2007)

AIMS/HYPOTHESIS

The objective of this study was to use Scottish national data to assess the influence of type 2 diabetes on (1) survival (overall and cause-specific) in multiple time intervals after diagnosis of colorectal cancer and (2) cause of death.

METHODS

Data from the Scottish Cancer Registry were linked to data from a population-based national diabetes register. All people in Scotland diagnosed with non-metastatic cancer of the colon or rectum in 2000-2007 were included. The effect of pre-existing type 2 diabetes on survival over four discrete time intervals (<1, 1-2, 3-5 and >5 years) after cancer diagnosis was assessed by Cox regression. Cumulative incidence functions were calculated representing the respective probabilities of death from the competing causes of colorectal cancer, cardiovascular disease, other cancers and any other cause.

RESULTS

Data were available for 19,505 people with colon or rectal cancer (1,957 with pre-existing diabetes). Cause-specific mortality analyses identified a stronger association between diabetes and cardiovascular disease mortality than that between diabetes and cancer mortality. Beyond 5 years after colon cancer diagnosis, diabetes was associated with a detrimental effect on all-cause mortality after adjustment for age, socioeconomic status and cancer stage (HR [95% CI]: 1.57 [1.19, 2.06] in men; 1.84 [1.36, 2.50] in women). For patients with rectal cancer, diabetes was not associated with differential survival in any time interval.

CONCLUSIONS/INTERPRETATION

Poorer survival observed for colon cancer associated with type 2 diabetes in Scotland may be explained by higher mortality from causes other than cancer.

External validity of randomized controlled trials of glycaemic control and vascular disease: how representative are participants?

AIMS

To describe the proportion of people with Type 2 diabetes living in Scotland who meet eligibility criteria for inclusion in several large randomized controlled trials of glycaemic control to inform physicians and guideline developers about the generalizibility of trial results.

METHODS

A literature review was performed to identify large trials assessing the impact of glycaemic control on risk of macrovascular disease. Inclusion and exclusion criteria from each trial were applied to data on the population of people with a diagnosis of Type 2 diabetes living in Scotland in 2008 (n = 180,590) in a population-based cross-sectional study and the number and proportion of people eligible for each trial was determined.

RESULTS

Seven trials were identified. The proportion of people with Type 2 diabetes who met the eligibility criteria for the trials ranged from 3.5 to 50.7%. Trial participants were younger at age of diagnosis of diabetes and at time of trial recruitment than in the Scottish study population. The application of upper age criteria excluded the largest proportion of patients, with up to 39% of people with Type 2 diabetes ineligible for a trial with the most stringent criteria based on age alone.

CONCLUSIONS

We found that many of the large trials of glycaemic control among people with Type 2 diabetes have limited external validity when applied to a population-based cohort of people with Type 2 diabetes. In particular, the age distribution of trial participants often does not reflect that of people with Type 2 diabetes in a contemporary British population.

Area-based socioeconomic status, type 2 diabetes and cardiovascular mortality in Scotland

AIMS/HYPOTHESIS

The aim of this study was to explore the relationships between type 2 diabetes mellitus, area-based socioeconomic status (SES) and cardiovascular disease mortality in Scotland.

METHODS

We used an area-based measure of SES, Scottish national diabetes register data linked to mortality records, and general population cause-specific mortality data to investigate the relationships between SES, type 2 diabetes and mortality from ischaemic heart disease (IHD) and cerebrovascular disease (CbVD), for 2001-2007. We used negative binomial regression to obtain age-adjusted RRs of mortality (by sex), comparing people with type 2 diabetes with the non-diabetic population.

RESULTS

Among 216,652 people aged 40 years or older with type 2 diabetes (980,687 person-years), there were 10,554 IHD deaths and 4,378 CbVD deaths. Age-standardised mortality increased with increasing deprivation, and was higher among men. IHD mortality RRs were highest among the least deprived quintile and lowest in the most deprived quintile (men: least deprived, RR 1.94 [95% CI 1.61, 2.33]; most deprived, RR 1.46 [95% CI 1.23, 1.74]) and were higher in women than men (women: least deprived, RR 2.84 [95% CI 2.12, 3.80]; most deprived, RR 2.04 [95% CI 1.55, 2.69]). A similar, weaker, pattern was observed for cerebrovascular mortality.

CONCLUSIONS/INTERPRETATION

Absolute risk of cardiovascular mortality is higher in people with diabetes than in the non-diabetic population and increases with increasing deprivation. The relative impact of diabetes on cardiovascular mortality differs by SES, and further efforts to reduce cardiovascular risk both in deprived groups and people with diabetes are required. Prevention of diabetes may reduce socioeconomic health inequalities.

Medical simulation for professional development--science and practice

From the earliest days of medical practice, when surgeons used cadavers to explore the possibilities of surgical intervention, simulation has been employed to advance the practice of health care. In the last 10 years, technological advances have allowed for a wider availability and greater realism of simulation, and this has encouraged a great expansion in its use. Simulation aims to create a virtuous cycle of professional development to improve patient outcomes. Although it seems eminently logical to believe that simulation will result in better outcomes, there is a need to test these new training interventions rigorously to be sure of their worth and to understand any limitations. The purpose of this BJOG supplement is to examine in depth several paradigms of medical simulation within maternity care and gynaecology, in different settings, looking at what can be achieved and how. In this opening review, we look at the potential use of medical simulation in broad terms and describe the types of evidence that can be employed to support its use.

Do men develop type 2 diabetes at lower body mass indices than women?

AIMS/HYPOTHESIS

To describe the associations between age, sex and BMI at diagnosis of type 2 diabetes, and test the hypothesis that men are diagnosed with diabetes at lower average BMI than women of similar age.

METHODS

Linear regression was used to estimate and compare the relationship between age and BMI at diagnosis among 51,920 men and 43,137 women included in a population-based diabetes register in Scotland for whom an index BMI measurement was taken within 1 year of diabetes diagnosis. We also examined HbA(1c) values by sex within the same timescale.

RESULTS

Mean BMI closest to date of diagnosis of type 2 diabetes mellitus was 31.83 kg/m(2) (SD 5.13) in men and 33.69 kg/m(2) (SD 6.43) in women. The inverse relationship between age and BMI at diagnosis of type 2 diabetes mellitus was significantly steeper in women than in men (slope estimate in men -0.12 kg/m(2) per year [95% CI -0.13, -0.12] women -0.18 kg/m(2) per year [95% CI -0.18, -0.17], p < 0.0001 for formal test of interaction). Mean BMI difference was most marked at younger ages and narrowed with advancing age. However, HbA(1c) levels within 1 year of diagnoses were broadly similar in men and women.

CONCLUSIONS/INTERPRETATION

Men are diagnosed with type 2 diabetes at lower BMI than women across the age range. This observation may help explain why type 2 diabetes is more common among middle-aged men in populations of European extraction. Whether the same pattern is also observed in other ethnic groups requires confirmation.

Effects of Atenolol, Labetalol and Methyldopa on Endogenous Antioxidants In-vitro

The aim of this study was to investigate whether atenolol, labetalol and methyldopa, which are commonly used for the treatment of hypertension in pregnancy, can induce antioxidant activity.

Reactive oxygen species scavengers (plasma thiol, red cell lysate thiol, red cell superoxide dismutase, red cell membrane thiol and plasma glutathione) were measured after incubation of peripheral blood with atenolol and methyldopa, respectively.

The results showed that atenolol and labetalol could significantly raise the levels of plasma thiol and membrane thiol but had no effects on lysate thiol, superoxide dismutase and glutathione. The effects on membrane thiol occurred after 60 min incubation and on plasma thiol after 120 min incubation.

The data also suggest that atenolol and labetalol at lower concentrations tend to have additive effects on reactive oxygen species scavengers but at higher concentrations do not.

Methyldopa had no significant effect on any of the parameters measured.

These findings suggest that atenolol and labetalol are able to induce higher levels of antioxidant activity.

Encoding and decoding mechanisms of pulsatile hormone secretion

Ultradian pulsatile hormone secretion underlies the activity of most neuroendocrine systems, including the hypothalamic-pituitary adrenal (HPA) and gonadal (HPG) axes, and this pulsatile mode of signalling permits the encoding of information through both amplitude and frequency modulation. In the HPA axis, glucocorticoid pulse amplitude increases in anticipation of waking, and, in the HPG axis, changing gonadotrophin-releasing hormone pulse frequency is the primary means by which the body alters its reproductive status during development (i.e. puberty). The prevalence of hormone pulsatility raises two crucial questions: how are ultradian pulses encoded (or generated) by these systems, and how are these pulses decoded (or interpreted) at their target sites? We have looked at mechanisms within the HPA axis responsible for encoding the pulsatile mode of glucocorticoid signalling that we observe in vivo. We review evidence regarding the 'hypothalamic pulse generator' hypothesis, and describe an alternative model for pulse generation, which involves steroid feedback-dependent endogenous rhythmic activity throughout the HPA axis. We consider the decoding of hormone pulsatility by taking the HPG axis as a model system and focussing on molecular mechanisms of frequency decoding by pituitary gonadotrophs.

Inflammation and preeclampsia

No individual can claim credit for all the advances made during his lifetime. However, certain individuals have a far greater influence than others. Prof. Christopher Redman has had a huge role to play in increasing the understanding of the aetiology, pathology, progression and management of preeclampsia. The work he did personally, led in others and stimulated in colleagues, both friend and foe, has helped to progress preeclampsia from a disease that came from nowhere to one that is more understood and safely managed. In this paper, it is the work in immunology that will be concentrated on in a chronological way but this will be linked to other relevant research and clinical practice. The understanding that preeclampsia is a two-stage disease starting in the placenta and progressing systemically has led to greater understanding as well as more questions. The universal role of immunology first as an acceptor within the placental bed then as a disease driver in the systemic circulation emphasises the good and the bad in physiological systems. Prof. Redman has been present in all these areas of discovery and enlightenment as will be described.

The profile of dermatological problems in primary care

BACKGROUND

Cutaneous disease is thought to account for 10-15% of patient consultations with general practitioners, but relatively little is known about the demography of dermatological conditions in primary care.

AIM

To assess the proportion and diagnostic profile of dermatological conditions seen in primary care in the southeast of Scotland, and to draw comparisons with secondary dermatological care.

METHODS

General practitioners in 13 general practices were asked to note all skin-related consultations during a 2-week period. The case notes of these patients were reviewed, and diagnosis and treatment was recorded. Patients who had consulted for the same skin disorder on >or= 3 occasions during the previous year were invited for assessment by a consultant dermatologist. Where possible, the case notes from 10% of all consultations during the 2-week study period were examined to assess accuracy of recording.

RESULTS

The percentage of consultations relating to cutaneous disorders varied between practices, ranging from 3% to 18.8%, with a mean of 8.4%. Eczema accounted for 22.5%, infections 20.3% and benign tumours for 11.4% of consultations with a dermatological basis. In contrast, in secondary care, benign tumours accounted for 23.8%, malignant tumours for 16.4% and eczema for 16.3% of dermatological consultations.

CONCLUSIONS

Dermatological disorders make up a significant proportion of general practitioners' workload. The diagnostic profile of primary-care dermatology differs markedly from that of hospital practice. General practitioners may benefit from training specifically tailored to the common primary-care dermatological conditions.

Fetal folate C677T methylenetetrahydrofolate reductase gene polymorphism and low birth weight

The aim of this study was to determine if fetal C677T methylenetetrahydrofolate reductase (MTHFR) genotype contributes to low birth weight. The study group consisted of 243 term babies with a birth weight<10th centile for gestational age, with subgroup analyses for those <1st centile. The control group consisted of 132 term babies with a birth weight 3.3-3.8 kg. Odds ratio analyses with 95% confidence intervals (CI) were calculated for carriage of the t allele and overall genotype frequencies. There was no significant difference in carriage of the t allele between study and control groups, odds ratio (OR) 0.79 (95% CI, 0.57-1.09). No differences were observed for frequencies of heterozygote and recessive homozygote genotypes for the two populations. In the subgroup analyses, no statistical differences were observed in the t allele frequency, frequency of the heterozygote or homozygote genotype. Trends were seen and the study suggests that fetal C677T MTHFR genotype may be a factor contributing to birth weight. The potential may exist to influence clinical outcome by maternal folate supplementation.

Interleukin-4 -590 (C>T), toll-like receptor-2 +2258 (G>A) and matrix metalloproteinase-9 -1562 (C>T) polymorphisms in pre-eclampsia

Functional single nucleotide polymorphisms (SNPs) of interleukin (IL)-4 -590 (C>T), toll-like receptor (TLR)-2 +2258 (G>A) and matrix metalloproteinase (MMP)-9 -1562 (C>T) were examined by polymerase chain reaction-restriction fragment length polymorphism to identify their merit as genetic markers for pre-eclampsia. One hundred and seventeen pre-eclamptic women and 146 control subjects with uncomplicated singleton pregnancies participated in this study, conducted at Leeds General Infirmary and St James's University Hospital. While the TLR-2 +2258 (G>A) and MMP-9 -1562 (C>T) SNPs failed to present any significant association with pre-eclampsia, there was a marked trend for an association between the IL-4 -590 (C>T) SNP and pre-eclampsia (chi(2)= 5.87, P = 0.055), with a prevalence of TT homozygous women in this group (OR 4.455, 95% CI 1.286-15.350).

Murine serum cytokines throughout the estrous cycle, pregnancy and post partum period

Cytokines are pleiotropic glycoproteins participating in many aspects of mammalian reproductive physiology. Although murine models have been established to study normal and pathological pregnancy, the small volume of retrievable sample has hampered investigations into the role of cytokines in these processes. These problems were overcome by using fluid-phase multiplex immunoassays to monitor the serum profiles of 18 cytokines in single animals throughout normal murine reproduction: estrus, diestrus, post coitum, preimplantation, implantation, mid-pregnancy, late pregnancy and post partum. Most cytokines were detectable throughout all stages studied. Modest changes in profile were associated with estrous cyclicity and early pregnancy while virtually all cytokine levels increased markedly in mid- to late pregnancy and either fell slightly or levelled off post partum. The functional interrelationships between the various cytokines and the hormonal milieu are discussed with respect to gestational stage. Although certain profiles supported the 'conventional' Th1:Th2 cytokine paradigm of pregnancy, many of the changes recorded were orchestrated around IL-12 (p40) and (p70). The present findings suggest that the traditional cytokine dichotomy poorly describes complex immunological processes like pregnancy.

First trimester maternal blood rheology and pregnancy induced hypertension

This study evaluates the relationship between the first trimester assessment of maternal rheology and the subsequent development of pregnancy induced hypertension. This is a prospective observational study based in the Glasgow Royal Maternity Hospital, Scotland. From an original population of 744 consecutive antenatal attendees a total of 579 women were booked at less than 14 weeks' gestation. The main study group is a further subset comprising 251 primigravid women booking with a singleton pregnancy without essential hypertension. Previously published data from a group of non-pregnant women of similar age drawn from the same local community was used for external comparison. Blood samples were collected at the booking visit, from which fibrinogen, red cell aggregation, haematocrit and plasma, whole blood, relative and corrected viscosities were recorded. Information was obtained from the case notes in retrospect starting approximately 1 year after the first patients had first been recruited into the trial. The overall outcome of the pregnancies was noted with particular reference to pregnancy induced hypertension (PIH), birth weight, antepartum haemorrhage, pre-term labour, perinatal death, condition at delivery and neonatal complication. Our results show PIH is associated with a significantly raised mean blood viscosity and fibrinogen at time of booking. All significance disappears after adjustment for smoking, diastolic blood pressure and age. Viscosity is, however, only marginally non-significant (p = 0.07). In conclusion, blood rheology, in particular blood viscosity and fibrinogen, may play a predictive role in the development of pregnancy-induced hypertension. When combined with measurement of smoking and diastolic blood pressure at booking, these measurements could be used to calculate a risk score for the development of PIH, allowing targeting of antenatal care. Further data is required.

Outcomes of severe pre-eclampsia/eclampsia in Yorkshire 1999/2003

OBJECTIVE

To establish the risk of serious complications from severe pre-eclampsia and eclampsia in a region using a common guideline for the management of these conditions.

DESIGN

A five-year prospective study.

SETTING

Sixteen maternity units in Yorkshire.

POPULATION

All women managed with severe pre-eclampsia and eclampsia.

METHODS

A common guideline was developed for the management of women with these conditions. A network of midwives prospectively collected outcome data.

MAIN OUTCOME MEASURE

Incidence of the conditions and serious complication rates.

RESULTS

A total of 210,631 women delivered in the 16 units between 1 January 1999 and 31 December 2003. One thousand eighty-seven women were diagnosed with severe pre-eclampsia or eclampsia (5.2/1000). One hundred and fifty-one women had serious complications including 82 women (39/10,000) having eclamptic seizures and 49 women (23/10,000) requiring ICU admission. There were no maternal deaths but 54 out of 1145 babies died before discharge, giving a mortality rate of 47.2/1000. Of the 82 cases of eclampsia, 45 occurred antenatally (55%), 18 before admission to the maternity unit. Eleven cases occurred in labour (13%), including 1 during a caesarean section, and 26 cases occurred following delivery (32%). Twenty-five women developed pulmonary oedema (2.3% of cases) and six women required renal dialysis (0.55% of cases). One hundred and sixty-five (15%) required no antihypertensive therapy and 489 (53%) of the remainder required only oral therapy. Two hundred and one (18.5%) required more than one drug.

CONCLUSION

A regional guideline for severe pre-eclampsia and eclampsia can be developed and implemented. Its use may contribute to a low rate of serious complications.

Towards improved neonatal outcome: future strategies

The role of the obstetrician is to help predict and prevent maternal/fetal infection/inflammation related to neonatal mortality and morbidity. Predictive studies have mainly focused on the high-risk phenotype. Currently, there is a scientific drive to analyse the genetic susceptibility of preterm birth (PTB). Studies of the combination of environmental and lifestyle risk factors with the known genotype may result in a better understanding of the causation of PTB. Predictive technical markers such as fibronectin, cervical length measurement and home uterine activity remain largely unproven. Current antenatal care has not achieved primary prevention of PTB. Tocolytics and antibiotics constitute the two key elements of secondary prevention. Tocolytics have a minimal benefit but should not be used to prolong an infected preterm pregnancy. The use of antibiotics in preterm premature rupture of membranes can prolong the pregnancy with a decrease in neonatal morbidity. Anti-inflammatory cytokines, cytokine inhibitors and soluble cytokine receptors are promising treatment options that could modulate the intra-amniotic inflammatory process.

An investigation into the association among preterm birth, cytokine gene polymorphisms and periodontal disease

OBJECTIVE

To investigate a putative relationship between preterm delivery and the carriage of polymorphic genes that code for the cytokines interleukin-1beta (IL-1beta) at codon +3953 and tumour necrosis factor-alpha (TNF-alpha) at codon -308 in a group of postpartum women and to elucidate if the concurrent presence of periodontal disease increased the risk of preterm delivery in this group.

DESIGN

Case-control study

SETTING

Postnatal wards at Guy's and St Thomas' Hospital Trust.

POPULATION

Postpartum women from southeast London, UK.

METHODS

Case subjects were defined as those who experienced a birth at less than 37 weeks of gestation. Control subjects gave birth at term. Demographic data were collected and a periodontal examination was performed. Blood samples were collected and analysed by restriction fragment length polymerase techniques for the presence of each of the allelic variants.

MAIN OUTCOME MEASURES

The level of periodontal disease and the carriage of allelic variants of IL-1beta+3953 and TNF-alpha-308 genes.

RESULTS

Forty-eight case subjects and 82 control subjects were assessed. There was no statistically significant difference in the carriage of the IL-1beta+3953 allelic variant between cases and controls (29%versus 18%, P= 0.112). However, 23 (48%) of the case subjects and 24 (29%) of controls were heterozygous or homozygous for the variant TNF-alpha-308 gene (odds ratio [OR] 2.2, 95% confidence interval [CI] 1.0-5.0, P= 0.026). There was no association between the carriage of either the polymorphic IL-1beta+3953 or TNF-alpha-308 variant and the severity of periodontal disease. The combination of periodontal disease and the allelic variant did not increase the risk of preterm delivery.

CONCLUSIONS

In this study, a higher proportion of women who delivered preterm carried the polymorphic TNF-alpha-308 gene. There did not appear to be any interaction between either of the genotypes and periodontal disease with preterm delivery as has been reported for bacterial vaginosis and the TNF-alpha-308 polymorphic gene.

Abnormal IL-2 receptor levels in non-pregnant women with a history of recurrent miscarriage

BACKGROUND

Immunological abnormalities have been found in pregnant women with a history of recurrent miscarriage. This study compared interleukin-2 receptor (IL-2R) levels in non-pregnant women with a history of recurrent miscarriage with those found in serum from a non-pregnant group with no such history.

METHODS

Group 1 comprised 49 non-pregnant women with a history of recurrent miscarriage (at least three consecutive miscarriages). Group 2 comprised 22 non-pregnant women with no history of miscarriage. Serum IL-2R levels were measured in all patients.

RESULTS

The results obtained showed that although all women were not pregnant at the time of sampling, IL-2R levels were significantly higher in women in Group 1 compared with those in Group 2 (1589 +/- 1289 versus 1082 +/- 823 pg/ml; P < 0.05). Follow-up data were available for 21 women from Group 1. The next pregnancy ended successfully for 14 of these women, while seven miscarried again. The IL-2R levels obtained pre-pregnancy were not significantly different between the two groups (1480 +/- 910 versus 1356 +/- 716 pg/ml).

CONCLUSION

This study has shown that non-pregnant women with a history of recurrent miscarriage have raised IL-2R levels. These increased pre-pregnancy IL-2R levels did not necessarily predict miscarriage for the next pregnancy.

Primary care reform: a pilot study to test the evaluative potential of the Patient Enablement Instrument in Poland

BACKGROUND

Primary health care reform is underpinned by a move towards patient-centred holistic care. This pilot study uses the Patient Enablement Instrument (PEI) to assess outcome at a fundamental level: that of the patient and their doctor at consultation.

OBJECTIVES

Our aim was to assess the evaluative potential of the PEI in relation to a reform programme in Poland by (i) comparing the outcomes of consultations (using the PEI) carried out by nine doctors (three diploma GPs who had participated in the training programme, three GPs who had not participated in the training programme and three polyclinic internists); and (ii) relating PEI scores to a proxy quality process measure (consultation length).

METHODS

A cross-sectional quantitative questionnaire survey was carried out using the PEI. The subjects were patients consulting with nine doctors distributed within a single region around Gdansk.

RESULTS

The overall results with the PEI and consultation length reflected UK experience. In addition, there were significant differences between groups in this pilot study. Patients seen by diploma GPs achieved higher patient enablement scores (mean 4.33, 95% confidence interval 4.09-4.58) relative to GPs (mean 3.44, 3.21-3.67) and polyclinic doctors (mean 3.23, 2.99-3.47). However, there is evidence of appreciable between-doctor variation in PEI scores within groups. The difference in patient enablement between groups was not affected by patient case mix, in contrast to the duration of consultation, which was. Holistically trained diploma GPs spent longer with patients with psychological problems. Patients seen by diploma GPs received longer consultations (mean 12.65 min, 95% confidence interval 12.18-13.13) relative to their colleagues (the GPs' mean was 10.11, 9.82-10.41 min; that of the polyclinic internists was 10.16, 9.81-10.50 min). The duration of consultation was positively correlated with patient enablement.

CONCLUSION

The results of such training courses should be examined from the perspective of both the patient and their doctor. Significant differences were found in both patient enablement and consultation length between patients attending groups of doctors delivering primary care, but working from different paradigms. This pilot shows promising results which, if repeated in a larger study, would provide an objective means of evaluating such reform programmes.

Interleukin-2 receptor concentrations in pregnant women with a history of recurrent miscarriage

BACKGROUND

The mechanism by which the maternal immune system tolerates the fetus during pregnancy is unclear.

METHODS

This study measured interleukin-2 receptor (IL-2R) concentrations in the serum of non-pregnant women (Group 1); healthy first trimester pregnant women (Group 2); pregnant women with a history of recurrent miscarriage whose pregnancies again failed later in the first trimester (Group 3); and first trimester pregnant women with a history of recurrent miscarriage but whose pregnancies on this occasion went successfully to term (Group 4). An initial sample was obtained from all women in Groups 1, 2, 3 and 4. A further sample was obtained 4 weeks later from women in Groups 1, 2 and 4.

RESULTS

The initial sample showed no significant difference in IL-2R concentrations between Groups 1 and 2. Concentrations were significantly higher in Groups 3 (667 +/- 244 U/ml; P < 0.003) and 4 (730 +/- 360 U/ml; P < 0.05) compared with healthy pregnant women (425 +/- 94). When the second sample was obtained concentrations in Group 4 were found to have fallen so that they no longer differed from Group 2.

CONCLUSIONS

Our results confirm earlier findings that a successful pregnancy is associated with significantly lower concentrations of IL-2R.

A digital system for recording the electrical activity of the uterus

The ability to identify true pre-term labour would be of considerable clinical benefit as electrical signals from the uterus, recorded using surface electrodes, may discriminate between labouring and non-labouring states in human pregnancy. A digital recording system for recording the electrical activity of the uterus has been developed and is described in this paper. A pilot study in which entire recordings in 21 women were subjected to power spectral analysis suggests that the relative power in two frequency bands (0.2-0.45 Hz and 0.8-3 Hz) changes as pregnancy progresses into early labour.

Abnormal immunoglobulin subclass patterns in women with a history of recurrent miscarriage

OBJECTIVE

To determine whether IgG subclass patterns differed between nonpregnant women, healthy pregnant women, and pregnant women with a history of recurrent miscarriage.

DESIGN

Controlled clinical study.

SETTING

An academic setting.

PATIENT(S)

Group 1 was comprised of 10 nonpregnant women, group 2 of 10 healthy pregnant women, group 3 of eight pregnant women with a history of recurrent miscarriage and whose pregnancies on this occasion went to term, and group 4 of 10 women with a history of recurrent miscarriage whose pregnancies again failed later in the first trimester.

INTERVENTION(S)

None of the patients received any medication.

MAIN OUTCOME MEASURE(S)

Serum levels of total IgG and IgG 1, 2, 3, and 4.

RESULT(S)

The results obtained showed that normal pregnancy was associated with a significant increase in total IgG production and an increase in IgG subclasses 1, 2, and 3. Women with a history of miscarriage, but who had a successful pregnancy on this occasion, showed a similar pattern of IgG subclasses. Women with a history of miscarriage and whose pregnancy again ended in miscarriage showed a different IgG subclass pattern.

CONCLUSION(S)

Pregnancies that ended in miscarriage showed a different pattern of IgG subclasses than those that continued to term. The changes seen in immunoglobulin patterns could be linked to changes in cytokine production.

Sympathetic neural mechanisms in normal and hypertensive pregnancy in humans

BACKGROUND

Direct recordings from peripheral sympathetic nerves have shown an increased sympathetic drive in pregnancy-induced hypertension (PIH) and preeclampsia (PE). It is unknown whether sympathetic drive is altered in normal pregnancy, when arterial blood pressure can be normal or relatively low. The aim of this study was to measure and compare peripheral sympathetic discharge, its vasoconstrictor effect and its baroreceptor control, during pregnancy and postpartum in women with normal pregnancy (NP) and PIH and in normotensive nonpregnant (NN) women.

METHODS AND RESULTS

Twenty-one women with NP, 18 women with PIH, and 21 NN women had muscle sympathetic nerve activity assessed from multiunit discharges (MSNA) and from single units with defined vasoconstrictor properties (s-MSNA). The s-MSNA in NP (38+/-6.6 impulses/100 beats) was greater (P<0.05) than in NN women (19+/-1.8 impulses/100 beats) despite similar age and body weight but less than in PIH women (P<0.001) (146+/-23.5 impulses/100 beats). MSNA followed a similar trend. Cardiac baroreceptor reflex sensitivity (BRS) was impaired in NP and PIH women relative to NN. After delivery, sympathetic activity decreased to values similar to those obtained in NN, and there was an increase in BRS. In women with NP, the decrease in sympathetic output occurred despite an insignificant change in blood pressure.

CONCLUSIONS

Central sympathetic output was increased in women with normal pregnancy and was even greater in the hypertensive pregnant group. The findings suggest that the moderate sympathetic hyperactivity during the latter months of normal pregnancy may help to return the arterial pressure to nonpregnant levels, although when the increase in activity is excessive, hypertension may ensue.

Focus for the future: tackling the 'pelvic pain' problem in gynecologic practice--an interactive session

OBJECTIVE

The clinical management of women with chronic pelvic pain (CPP) and endometriosis involves important issues that exist at the interface between these two conditions.

METHODS

To address these issues, an interactive session was convened to discuss an empiric algorithmic protocol for the clinical management of CPP and endometriosis presented during the Takeda-sponsored session as part of the XVI FIGO World Congress of Gynecology and Obstetrics and to monitor the audience response to this approach.

RESULTS

Approximately one-third of the audience responded that they would definitely try this method, approximately 18% were already using it, and approximately 21% would be fairly likely to try it. Thirty percent of the audience was not convinced that the empiric approach is the best management strategy.

CONCLUSION

The advantages of this management strategy should be carefully considered, and discussed with colleagues who do think it is the reasonable treatment approach in selected cases.

Focus for the future: tackling the 'pelvic pain' problem in gynecologic practice - an interactive session

OBJECTIVE

The clinical management of women with chronic pelvic pain (CPP) and endometriosis involves important issues that exist at the interface between these two conditions.

METHODS

To address these issues, an interactive session was convened to discuss an empiric algorithmic protocol for the clinical management of CPP and endometriosis presented during the Takeda-sponsored session as part of the XVI FIGO World Congress of Gynecology and Obstetrics and to monitor the audience response to this approach.

RESULTS

Approximately one-third of the audience responded that they would definitely try this method, approximately 18% were already using it, and approximately 21% would be fairly likely to try it. Thirty percent of the audience was not convinced that the empiric approach is the best management strategy.

CONCLUSION

The advantages of this management strategy should be carefully considered, and discussed with colleagues who do think it is the reasonable treatment approach in selected cases.

The association between deprivation levels, attendance rate and triage category of children attending a children's accident and emergency department

OBJECTIVE

To determine the relation between deprivation category, triage score and accident and emergency (A&E) attendance for children under the age of 13.

DESIGN

Retrospective study of all children attending an A&E department over one year.

SETTING

A paediatric teaching hospital in Edinburgh.

SUBJECTS

All children attending the A&E department who had a postcode and a triage score documented on attendance. The postcode was used to determine the deprivation category and the triage scored the severity of illness or injury.

MAIN OUTCOME MEASURE

The relation between deprivation category, triage score and frequency of attendance.

RESULTS

There is a trend towards increased attendance in all triage categories for deprivation categories 6 and 7.

CONCLUSIONS

Attendance at A&E is not only related to severity of injury but also to deprivation category. The reason why people from disadvantaged areas attend more frequently needs further evaluation.

The carriage of pro-inflammatory cytokine gene polymorphisms in recurrent pregnancy loss

PROBLEM

Recurrent pregnancy loss (RPL) affects 2-4% of couples, and remains largely unexplained. Recent studies have examined the role of cytokines in the maintenance of normal pregnancy, which is linked with an increased expression of Th2 cytokines. Overexpression of Th1 cytokines is associated with RPL. Knowing that functional polymorphisms exist for certain cytokines, it has therefore been suggested that women with RPL may have a genetic predisposition to overexpress Th1 cytokines.

METHOD OF STUDY

The genes for interleukin-1 beta (IL-1beta) and tumor necrosis factor alpha (TNF-alpha) carry functional gene polymorphisms. In both cases these are biallelic polymorphisms that can be detected by polymerase chain reaction followed by restriction fragment length polymorphism. The aim of this pilot study was to assess whether carriage of the rarer alleles (TNF*2 and IL-1B*2) could act as independent risk factors in recurrent miscarriage.

RESULTS

We found an increased incidence in the carriage of TNF*2, more pronounced in those women with two or more miscarriages. Carriage of the IL-1B*2 either alone or in association with TNF*2 was not associated with recurrent miscarriage.

CONCLUSION

There may be a role for these cytokine gene polymorphisms in RPL.

Developing a 'consultation quality index' (CQI) for use in general practice

BACKGROUND

The core values of general practice include holism and patient-centredness. None of the measures of quality of care in general practice presently capture the expression of these values at routine consultations.

OBJECTIVES

The aim of the present study was to construct a 'consultation quality index' (CQI) which reflects the core values of general practice, using as proxies 'consultation length' and how well patients 'know the doctor' as process measures and 'patient enablement' as an outcome measure.

METHODS

The CQI was constructed from data collected from 23 799 adult English-speaking patients consulting 221 doctors in four demographically contrasting areas of the UK during 2 weeks of March/April 1998. A total of 171 doctors who entered 50 qualifying consultations were allocated scores for the three component variables, and a total CQI was calculated.

RESULTS

CQI scores were in the range 4-18. Validity was examined by looking at high and low scorers in greater detail and by searching for correlates with case mix, patient age and gender, and the deprivation scores of the practices concerned. Particular attention was paid to how registrars and doctors new to their practices scored. The scores of different doctors in the same practice were also noted. The results had strong face validity and were independent of case mix and deprivation. Reliability was gauged by examining similar work from a previous study which had collected information on consultation length and enablement over three time periods. High CQI scores were associated with smaller overall practice list sizes.

CONCLUSIONS

We have outlined possible uses for the CQI as part of the packages assessing quality of care by doctors and practices. The measure may also have a part to play in recognizing poorly performing doctors. We suggest how CQI scores could contribute to an incentive scheme to reward good consulting practice. Further work is in hand to compare doctors' CQI scores with scores based on performance indicators constructed from routine NHS data on prescribing and preventive medicine.