Chronic hypertension, perinatal mortality and the impact of preterm delivery: a population-based study

OBJECTIVES

To estimate the association between chronic hypertension and perinatal mortality and to evaluate the extent to which risks are impacted by preterm delivery.

DESIGN

Cross-sectional analysis.

SETTING

United States, 2015-18.

POPULATION

Singleton births (20-44 weeks of gestation).

EXPOSURE

Chronic hypertension, defined as elevated blood pressure diagnosed before pregnancy or recognised before 20 weeks of gestation.

MAIN OUTCOMES AND MEASURES

We derived the risk of perinatal mortality in relation to chronic hypertension from Poisson models, adjusted for confounders. The impacts of misclassification and unmeasured confounding were assessed. Causal mediation analysis was performed to quantify the impact of preterm delivery on the association.

RESULTS

Of the 15 090 678 singleton births, perinatal mortality rates were 22.5 and 8.2 per 1000 births in chronic hypertensive and normotensive pregnancies, respectively (adjusted risk ratio 2.05, 95% CI 2.00-2.10). Corrections for exposure misclassification and unmeasured confounding biases substantially increased the risk estimate. Although causal mediation analysis revealed that most of the association of chronic hypertension on perinatal mortality was mediated through preterm delivery, the perinatal mortality rates were highest at early term, term and late term gestations, suggesting that a planned early term delivery at 37-38^6/7  weeks may optimally balance risk in these pregnancies. Additionally, 87% (95% CI 84-90%) of perinatal deaths could be eliminated if preterm deliveries, as a result of chronic hypertension, were preventable.

CONCLUSIONS

Chronic hypertension is associated with increased risk for perinatal mortality. Planned early term delivery and targeting modifiable risk factors for chronic hypertension may reduce perinatal mortality rates.

TWEETABLE ABSTRACT

Maternal chronic hypertension is associated with increased risk for perinatal mortality, largely driven by preterm birth.

Maternal serum fructosamine levels and stillbirth: a case-control study of the Stillbirth Collaborative Research Network

OBJECTIVE

To evaluate the association between maternal fructosamine levels at the time of delivery and stillbirth.

DESIGN

Secondary analysis of a case-control study.

SETTING

Multicentre study of five geographic catchment areas in the USA.

POPULATION

All singleton stillbirths with known diabetes status and fructosamine measurement, and representative live birth controls.

MAIN OUTCOME MEASURES

Fructosamine levels in stillbirths and live births among groups were adjusted for potential confounding factors, including diabetes. Optimal thresholds of fructosamine to discriminate stillbirth and live birth.

RESULTS

A total of 529 women with a stillbirth and 1499 women with a live birth were included in the analysis. Mean fructosamine levels were significantly higher in women with a stillbirth than in women with a live birth after adjustment (177 ± 3.05 versus 165 ± 2.89 μmol/L, P < 0.001). The difference in fructosamine levels between stillbirths and live births was greater among women with diabetes (194 ± 8.54 versus 162 ± 3.21 μmol/L), compared with women without diabetes (171 ± 2.50 versus 162 ± 2.56 μmol/L). The area under the curve (AUC) for fructosamine level and stillbirth was 0.634 (0.605-0.663) overall, 0.713 (0.624-0.802) with diabetes and 0.625 (0.595-0.656) with no diabetes.

CONCLUSIONS

Maternal fructosamine levels at the time of delivery were higher in women with stillbirth compared with women with live birth. Differences were substantial in women with diabetes, suggesting a potential benefit of glycaemic control in women with diabetes during pregnancy. The small differences noted in women without diabetes are not likely to justify routine screening in all cases of stillbirth.

TWEETABLE ABSTRACT

Maternal serum fructosamine levels are higher in women with stillbirth than in women with live birth, especially in women with diabetes.

Stillbirth and fetal anomalies: secondary analysis of a case-control study

OBJECTIVE

Approximately 10% of stillbirths are attributed to fetal anomalies, but anomalies are also common in live births. We aimed to assess the relationship between anomalies, by system and stillbirth.

DESIGN

Secondary analysis of a prospective, case-control study.

SETTING

Multicentre, 59 hospitals in five regional catchment areas in the USA.

POPULATION OR SAMPLE

All stillbirths and representative live birth controls.

METHODS

Standardised postmortem examinations performed in stillbirths, medical record abstraction for stillbirths and live births.

MAIN OUTCOME MEASURES

Incidence of major anomalies, by type, compared between stillbirths and live births with univariable and multivariable analyses using weighted analysis to account for study design and differential consent.

RESULTS

Of 465 singleton stillbirths included, 23.4% had one or more major anomalies compared with 4.3% of 1871 live births. Having an anomaly increased the odds of stillbirth; an increasing number of anomalies was more highly associated with stillbirth. Regardless of organ system affected, the presence of an anomaly increased the odds of stillbirth. These relationships remained significant if stillbirths with known genetic abnormalities were excluded. After multivariable analyses, the adjusted odds ratio (aOR) of stillbirth for any anomaly was 4.33 (95% CI 2.80-6.70) and the systems most strongly associated with stillbirth were cystic hygroma (aOR 29.97, 95% CI 5.85-153.57), and thoracic (aOR16.18, 95% CI 4.30-60.94) and craniofacial (aOR 35.25, 95% CI 9.22-134.68) systems.

CONCLUSIONS

In pregnancies affected by anomalies, the odds of stillbirth are higher with increasing numbers of anomalies. Anomalies of nearly any organ system increased the odds of stillbirth even when adjusting for gestational age and maternal race.

TWEETABLE ABSTRACT

Stillbirth risk increases with anomalies of nearly any organ system and with number of anomalies seen.

Acute ischaemic stroke: challenges for the intensivist

PURPOSE

To provide an update about the rapidly developing changes in the critical care management of acute ischaemic stroke patients.

METHODS

A narrative review was conducted in five general areas of acute ischaemic stroke management: reperfusion strategies, anesthesia for endovascular thrombectomy, intensive care unit management, intracranial complications, and ethical considerations.

RESULTS

The introduction of effective reperfusion strategies, including IV thrombolysis and endovascular thrombectomy, has revolutionized the management of acute ischaemic stroke and transformed outcomes for patients. Acute therapeutic efforts are targeted to restoring blood flow to the ischaemic penumbra before irreversible tissue injury has occurred. To optimize patient outcomes, secondary insults, such as hypotension, hyperthermia, or hyperglycaemia, that can extend the penumbral area must also be prevented or corrected. The ICU management of acute ischaemic stroke patients, therefore, focuses on the optimization of systemic physiological homeostasis, management of intracranial complications, and neurological and haemodynamic monitoring after reperfusion therapies. Meticulous blood pressure management is of central importance in improving outcomes, particularly in patients that have undergone reperfusion therapies.

CONCLUSIONS

While consensus guidelines are available to guide clinical decision making after acute ischaemic stroke, there is limited high-quality evidence for many of the recommended interventions. However, a bundle of medical, endovascular, and surgical strategies, when applied in a timely and consistent manner, can improve long-term stroke outcomes.

Severe maternal morbidity during delivery hospitalisation in a large international administrative database, 2008-2013: a retrospective cohort

OBJECTIVE

This study utilized the Dr. Foster Global Comparators database to identify pregnancy complications and associated risk factors that led to severe maternal morbidity during delivery hospitalisations in large university hospitals based in the USA, Australia, and England.

DESIGN

Retrospective cohort.

SETTING

Births in the USA, England and Australia from 2008 to 2013.

SAMPLE

Data from delivery hospitalisations between 2008 and 2013 were examined using the Dr. Foster Global Comparators database.

METHODS

We identified delivery hospitalisations with life-threatening diagnoses or use of life-saving procedures, using algorithms for severe maternal morbidity from the Center for Disease Control. Frequency of severe maternal morbidity was calculated for each country.

MAIN OUTCOME MEASURES

Multivariable analysis was used to examine the association between morbidity and socio-demographic and clinical characteristics within each country. Chi-square tests assessed differences in covariates between countries.

RESULTS

From 2008 to 2013, there were 516 781 deliveries from a total of 18 hospitals: 24.5% from the USA, 57.0% from England and 18.4% from Australia. Overall severe maternal morbidity rate was 8.2 per 1000 deliveries: 15.6 in the USA, 5.0 in England, and 8.2 in Australia. The most common codes identifying severe morbidity included transfusion, disseminated intravascular coagulation, acute renal failure, cardiac events/procedures, ventilation, hysterectomy, and eclampsia. Advanced maternal age, hypertension, diabetes, and substance abuse were associated with severe maternal morbidity in all three countries.

CONCLUSION

Rates of severe maternal morbidity differed by country. Identification of geographical, socio-demographic, and clinical differences can help target modifications of practice and potentially reduce severe maternal morbidity.

TWEETABLE ABSTRACT

Rates of severe maternal morbidity vary, but risk factors associated with adverse outcomes are similar in developed countries.

P109 Experience of tunnelled vs. bolt EVDs on the intensive care unit

Objectives

The placement of an external ventricular drain (EVD) is a common neurosurgical operation that carries great benefit in acute hydrocephalus but is not without risk. In our centre, bolt EVDs (B-EVD) are being placed in favour of tunnelled EVDs (T-EVD). The former has allowed for urgent CSF diversion in ITU. We compared EVD survival and complication rates between the two types of EVDs.

Design

Single centre prospective case-cohort.

Subjects

Twenty-five patients with B-EVDs and thirty-four patients with T-EVDs.

Methods

Clinical notes and radiographic reports were collected before and after the placement of EVDs for patients in ITU between January 2017 and June 2018.

Results

Fourteen of the 25 B-EVDs were placed on ITU, of which 2 were under stealth guidance. All 34 T-EVDs were placed in theatre. Mean time to CSF access after decision for diversion was 134 min in the B-EVD group and 227 min in the T-EVD group (p<0.05). Mean survival was 35 days for B-EVDs and 29 days for T-EVDs (p<0.05). Eight T-EVDs went onto be replaced as B-EVDs due to retraction or infection. Complications including infection, detachment or retraction were higher in the T-EVD group at 32% compared to 20% in the B-EVD group.

Conclusions

Bolt EVDs have a lower frequency of complications and higher survival compared to tunnelled EVDs. Since B-EVDs require fewer resources they can be placed faster and on ITU.

WM1-7 Brain parenchymal oxygen monitoring in delayed cerebral ischaemia

Objectives

At this single centre, tri-modal monitoring of ICP, temperature and direct brain tissue oxygen tension (PbtO2) is used to guide management of delayed cerebral ischaemia (DCI). We describe our experience of PbtO2 monitoring and its relationship with symptoms of DCI, regional cerebral blood flow (rCBF, perfusion imaging), intra-arterial chemical angioplasty and CSF diversion.

Design

Prospective cohort.

Subjects

Patients with aSAH who underwent over 24 hours of multi-modal PbtO2, temperature and intracranial pressure (ICP) monitoring via a Raumedic NEUROVENT-PTO probe.

Methods

Longitudinal analysis of PbtO2 values, presented as mmHg (mean±SD).

Results

Analysis of 1392 hours of tri-modal monitoring in 13 SAH patients. PbtO2 decreases >50% consistently reproduced focal neurological deficit. Symptomatic PbtO2 values ranged from 12–20 mmHg. Of the six patients who had reduced rCBF, all had a mean PbtO2 <15 mmHg. Five patients underwent intra-arterial chemical angioplasty (10 mg Verapamil in 100 ml NaCl over 30–40 mins). PbtO2 increased by at least 30% for 3.4±0.47 hours. CSF diversion resulted in a sustained mean increase in PbtO2 of 7.6±2.94 mmHg over the first 5 min (p=0.034).

Conclusions

PbtO2 <15 mmHg may predict development of a clinical deficit. Chemical angioplasty resulted in a pronounced but short-lived increase in PbtO2. CSF diversion resulted in a persistent increase in PbtO2. PbtO2 targeted management may be a valuable addition to the clinicians’ arsenal against DCI.

Cervical funneling or intra-amniotic debris and preterm birth in nulliparous women with midtrimester cervical length less than 30 mm

OBJECTIVE

To evaluate whether the presence of cervical funneling or intra-amniotic debris identified in the second trimester is associated with a higher rate of preterm birth (PTB) in asymptomatic nulliparous pregnant women with a midtrimester cervical length (CL) less than 30 mm (i.e. below the 10th percentile).

METHODS

This was a secondary cohort analysis of data from a multicenter trial in nulliparous women between 16 and 22 weeks' gestation with a singleton gestation and CL less than 30 mm on transvaginal ultrasound, randomized to treatment with either 17-alpha-hydroxyprogesterone caproate or placebo. Sonographers were centrally certified in CL measurement, as well as in identification of intra-amniotic debris and cervical funneling. Univariable and multivariable analysis was performed to assess the associations of cervical funneling and intra-amniotic debris with PTB.

RESULTS

Of the 657 women randomized, 112 (17%) had cervical funneling only, 33 (5%) had intra-amniotic debris only and 45 (7%) had both on second-trimester ultrasound. Women with either of these findings had a shorter median CL than those without (21.0 mm vs 26.4 mm; P < 0.001). PTB prior to 37 weeks was more likely in women with cervical funneling (37% vs 21%; odds ratio (OR), 2.2 (95% CI, 1.5-3.3)) or intra-amniotic debris (35% vs 23%; OR, 1.7 (95% CI, 1.1-2.9)). Results were similar for PTB before 34 and before 32 weeks' gestation. After multivariable adjustment that included CL, PTB < 34 and < 32 weeks continued to be associated with the presence of intra-amniotic debris (adjusted OR (aOR), 1.85 (95% CI, 1.00-3.44) and aOR, 2.78 (95% CI, 1.42-5.45), respectively), but not cervical funneling (aOR, 1.17 (95% CI, 0.63-2.17) and aOR, 1.45 (95% CI, 0.71-2.96), respectively).

CONCLUSIONS

Among asymptomatic nulliparous women with midtrimester CL less than 30 mm, the presence of intra-amniotic debris, but not cervical funneling, is associated with an increased risk for PTB before 34 and 32 weeks' gestation, independently of CL. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Targeted temperature management in patients with intracerebral haemorrhage, subarachnoid haemorrhage, or acute ischaemic stroke: consensus recommendations

BACKGROUND

A modified Delphi approach was used to identify a consensus on practical recommendations for the use of non-pharmacological targeted temperature management in patients with intracerebral haemorrhage, subarachnoid haemorrhage, or acute ischaemic stroke with non-infectious fever (assumed neurogenic fever).

METHODS

Nine experts in the management of neurogenic fever participated in the process, involving the completion of online questionnaires, face-to-face discussions, and summary reviews, to consolidate a consensus on targeted temperature management.

RESULTS

The panel's recommendations are based on a balance of existing evidence and practical considerations. With this in mind, they highlight the importance of managing neurogenic fever using a single protocol for targeted temperature management. Targeted temperature management should be initiated if the patient temperature increases above 37.5°C, once an appropriate workup for infection has been undertaken. This helps prevent prophylactic targeted temperature management use and ensures infection is addressed appropriately. When neurogenic fever is detected, targeted temperature management should be initiated rapidly if antipyretic agents fail to control the temperature within 1 h, and should then be maintained for as long as there is potential for secondary brain damage. The recommended target temperature for targeted temperature management is 36.5-37.5°C. The use of advanced targeted temperature management methods that enable continuous, or near continuous, temperature measurement and precise temperature control is recommended.

CONCLUSIONS

Given the limited heterogeneous evidence currently available on targeted temperature management use in patients with neurogenic fever and intracerebral haemorrhage, subarachnoid haemorrhage, or acute ischaemic stroke, a Delphi approach was appropriate to gather an expert consensus. To aid in the development of future investigations, the panel provides recommendations for data gathering.

Predicting Vaginal Delivery in Nulliparous Women Undergoing Induction of Labor at Term

OBJECTIVE

We sought to develop a model to calculate the likelihood of vaginal delivery in nulliparous women undergoing induction at term.

STUDY DESIGN

We obtained data from the Consortium on Safe Labor by including nulliparous women with term singleton pregnancies undergoing induction of labor at term. Women with contraindications for vaginal delivery were excluded. A stepwise logistic regression analysis was used to identify the predictors associated with vaginal delivery by considering maternal characteristics and comorbidities and fetal conditions. The receiver operating characteristic curve, with an area under the curve (AUC) was used to assess the accuracy of the model.

RESULTS

Of 10,591 nulliparous women who underwent induction of labor, 8,202 (77.4%) women had vaginal delivery. Our model identified maternal age, gestational age at delivery, race, maternal height, prepregnancy weight, gestational weight gain, cervical exam on admission (dilation, effacement, and station), chronic hypertension, gestational diabetes, pregestational diabetes, and abruption as significant predictors for successful vaginal delivery. The overall predictive ability of the final model, as measured by the AUC was 0.759 (95% confidence interval, 0.749-0.770).

CONCLUSION

We identified independent risk factors that can be used to predict vaginal delivery among nulliparas undergoing induction at term. Our predictor provides women with additional information when considering induction.

Increased Frequency of BK Virus-Specific Polyfunctional CD8+ T Cells Predict Successful Control of BK Viremia After Kidney Transplantation

BACKGROUND

BK virus infection remains an important cause of loss of allograft function after kidney transplantation. We sought to determine whether polyfunctional T cells secreting multiple cytokines simultaneously, which have been shown to be associated with viral control, could be detected early after start of BK viremia, which would provide insight into the mechanism of successful antiviral control.

METHODS

Peripheral blood mononuclear cells collected during episodes of BK viral replication were evaluated by multiparameter flow cytometry after stimulation by overlapping peptide pools of BK virus antigen to determine frequency of CD8+ and CD4+ T cells expressing 1 or more cytokines simultaneously, as well as markers of T-cell activation, exhaustion, and maturation.

RESULTS

BK virus controllers, defined as those with episodes of BK viremia of 3 months or less, had an 11-fold increase in frequency of CD8+ polyfunctional T cells expressing multiple cytokines, as compared with patients with prolonged episodes of BK viremia. Patients with only low level BK viremia expressed low frequencies of polyfunctional T cells. Polyfunctional T cells were predominantly of the effector memory maturation subtype and expressed the cytotoxicity marker CD107a.

CONCLUSIONS

Noninvasive techniques for immune assessment of peripheral blood can provide insight into the mechanism of control of BK virus replication and may allow for future patient risk stratification and customization of immune suppression at the onset of BK viremia.

Neonatal complications associated with use of fetal scalp electrode: a retrospective study

OBJECTIVES

To estimate the incidence and risk of complications associated with a fetal scalp electrode and to determine whether its application in the setting of operative vaginal delivery was associated with increased neonatal morbidity.

DESIGN

Retrospective cohort study.

SETTING

Twelve clinical centers with 19 hospitals across nine American Congress of Obstetricians and Gynecologists US districts.

POPULATION

Women in the USA.

METHODS

We evaluated 171 698 women with singleton deliveries ≥ 23 weeks of gestation in a secondary analysis of the Consortium on Safe Labor study between 2002 and 2008, after excluding conditions that precluded fetal scalp electrode application such as prelabour caesarean delivery. Secondary analysis limited to operative vaginal deliveries ≥ 34 weeks of gestation was also performed.

MAIN OUTCOME MEASURES

Incidences and adjusted odds ratios with 95% confidence intervals of neonatal complications were calculated, controlling for maternal characteristics, delivery mode and pregnancy complications.

RESULTS

Fetal scalp electrode was used in 37 492 (22%) of deliveries. In non-operative vaginal delivery, fetal scalp electrode was associated with increased risk of injury to scalp due to birth trauma (1.2% versus 0.9%; adjusted odds ratios 1.62; 95% confidence intervals 1.41-1.86) and cephalohaematoma (1.0% versus 0.9%; adjusted odds ratios 1.57; 95% confidence intervals 1.36-1.83). Neonatal complications were not significantly different comparing fetal scalp electrode with vacuum-assisted vaginal delivery and vacuum-assisted vaginal delivery alone or comparing fetal scalp electrode with forceps-assisted vaginal delivery and forceps-assisted vaginal delivery alone.

CONCLUSIONS

We found increased neonatal morbidity with fetal scalp electrode though the absolute risk was very low. It is possible that these findings reflect an underlying indication for its use. Our findings support the use of fetal scalp electrodes when clinically indicated.

TWEETABLE ABSTRACT

Neonatal risks associated with fetal scalp electrode use were low (injury to scalp 1.2% and cephalohaematoma 1.0%).

The association of beta-2 adrenoceptor genotype with short-cervix mediated preterm birth: a case-control study

OBJECTIVE

To determine whether β2 -adrenoceptor (β2 AR) genotype is associated with shortening of the cervix or with preterm birth (PTB) risk among women with a short cervix in the second trimester.

DESIGN

A case-control ancillary study to a multicentre randomised controlled trial.

SETTING

Fourteen participating centres of the Maternal-Fetal Medicine Units Network of the Eunice Kennedy Shriver National Institute of Child Health and Human Development.

POPULATION

Four hundred thirty-nine women, including 315 with short cervix and 124 with normal cervical length.

METHODS

Nulliparous women with cervical length <30 mm upon a 16-22-week transvaginal sonogram and controls frequency-matched for race/ethnicity with cervical lengths ≥40 mm were studied. β2 AR genotype was determined at positions encoding for amino acid residues 16 and 27.

MAIN OUTCOME MEASURES

Genotype distributions were compared between case and control groups. Within the short cervix group, pregnancy outcomes were compared by genotype, with a primary outcome of PTB <37 weeks.

RESULTS

Genotype data were available at position 16 for 433 women and at position 27 for 437. Using a recessive model testing for association between short cervix and genotype, and adjusted for ethnicity, there was no statistical difference between cases and controls for Arg16 homozygosity (OR 0.7, 95% CI 0.4-1.3) or Gln27 homozygosity (OR 0.9, 95% CI 0.3-2.7). Among cases, Arg16 homozygosity was not associated with protection from PTB or spontaneous PTB. Gln27 homozygosity was not associated with PTB risk, although sample size was limited.

CONCLUSIONS

β2 AR genotype does not seem to be associated with short cervical length or with PTB following the second-trimester identification of a short cervix. Influences on PTB associated with β2 AR genotype do not appear to involve a short cervix pathway.

International issues in stillbirth

The phenomenon of stillbirth has been poorly addressed in terms of reported statistics and as a clinical issue. A Study Group of the European Association of Perinatal Medicine reviewed the topic and highlighted specific issues. Such proposal was discussed in an open workshop held in Modena, Italy last year and this paper reports the final recommendations. Briefly, at least 22 completed weeks of gestation was endorsed as definition for including SB in statistics and for clinical studies. A minimum diagnostic work-up was suggested together with the emphasis toward a local, multidisciplinary audit process, in order to comprehend causality. Attention for parents emotional support and appropriate counselling was believed as essential part of the clinical process. Finally, the need for funding comprehensive research programs in SB through international, multidisciplinary involvement was believed mandatory for developing effective preventative strategies to avert the devastating occurrence of stillbirth.

Tetrahydrobiopterin: a novel antihypertensive therapy

Tetrahydrobiopterin (BH(4)) is a cofactor for the nitric oxide (NO) synthase enzymes, such that its insufficiency results in uncoupling of the enzyme, leading to release of superoxide rather than NO in disease states, including hypertension. We hypothesized that oral BH(4) will reduce arterial blood pressure (BP) and improve endothelial function in hypertensive subjects. Oral BH(4) was given to subjects with poorly controlled hypertension (BP >135/85 mm Hg) and weekly measurements of BP and endothelial function made. In Study 1, 5 or 10 mg kg(-1) day(-1) of BH(4) (n=8) was administered orally for 8 weeks, and in Study 2, 200 and 400 mg of BH(4) (n=16) was given in divided doses for 4 weeks. Study 1: significant reductions in systolic (P=0.005) and mean BP (P=0.01) were observed with both doses of BH(4). Systolic BP was 15+/-15 mm Hg (P=0.04) lower after 5 weeks and persisted for the 8-week study period. Study 2: subjects given 400 mg BH(4) had decreased systolic (P=0.03) and mean BP (P=0.04), with a peak decline of 16+/-19 mm Hg (P=0.04) at 3 weeks. BP returned to baseline 4 weeks after discontinuation. Significant improvement in endothelial function was observed in Study 1 subjects and those receiving 400 mg BH(4). There was no significant change in subjects given the 200 mg dose. This pilot investigation indicates that oral BH(4) at a daily dose of 400 mg or higher has a significant and sustained antihypertensive effect in subjects with poorly controlled hypertension, an effect that is associated with improved endothelial NO bioavailability.

Heritability of flow-mediated dilation: a twin study

BACKGROUND

Endothelial dysfunction assessed by brachial artery flow-mediated dilation (FMD) is a marker for early atherosclerotic vascular disease and future cardiovascular events.

OBJECTIVE

To estimate the heritability of brachial artery FMD using a twin design.

METHODS

We estimated the heritability of FMD using 94 middle-aged male twin pairs. FMD was measured by ultrasound, and traditional coronary heart disease risk factors were measured. Genetic modeling techniques were used to determine the relative contributions of genes and environment to the variation in FMD.

RESULTS

The mean age of the twin participants was 54.9 +/- 2.8 years. The mean FMD was 0.047 +/- 0.030. The intraclass correlation coefficient was higher in MZ twins [0.38, 95% confidence interval (CI) 0.32-0.43] than in DZ twins (0.19, 95% CI 0.11-0.26), suggesting a role of genetic influence in FMD variation. Structural equation modeling showed that both genetic and unique environmental factors contributed significantly to the variation in FMD. The crude FMD heritability was 0.37 (95% CI 0.15-0.54). After adjustment for traditional cardiovascular risk factors, including age, total cholesterol, blood pressure, and body mass index, the heritability of FMD was 39% (95% CI 0.18-0.56). The remaining variation in FMD could be explained by individual-specific environment.

CONCLUSION

This is the first study using twins to estimate the relative contributions of genetics and environment to the variation in FMD in a US population. Our results demonstrate a moderate genetic effect on brachial artery FMD, independent of traditional coronary risk factors. Our data also highlight the importance of unique environment on the variability in FMD.

Antiangiogenic therapy with interferon alfa for neovascular age-related macular degeneration

BACKGROUND

Antiangiogenic therapy is a new approach to the treatment of neovascular age-related macular degeneration. Interferon alfa is one antiangiogenic agent thought to function by inhibiting the migration and proliferation of vascular endothelial cells. It has been used in the treatment of hepatitis, solid tumors and hematologic malignancies.

OBJECTIVES

The aim of this review was to investigate interferon alfa as a treatment modality for neovascular age-related macular degeneration.

SEARCH STRATEGY

We searched and identified trials from the Cochrane Central Register of Controlled Trials (CENTRAL), which contains the Cochrane Eyes and Vision Group Trials Register, in The Cochrane Library (Issue 2, 2005), MEDLINE (1966 to 2005/06 week 1), EMBASE (1980 to 2005/week 23), LILACS (Latin American and Caribbean Health Science Literature Database) (June 2005) and the reference lists of included studies.

SELECTION CRITERIA

This review included randomized controlled trials evaluating interferon alfa therapy in people with neovascular age-related macular degeneration who were followed for at least one year.

DATA COLLECTION AND ANALYSIS

Both review authors independently extracted data and assessed trial quality. No data synthesis was conducted as only one trial met the inclusion criteria.

MAIN RESULTS

The one included trial enrolled and randomized 481 participants from 45 centers worldwide into four groups. The study allowed for analysis of the number of participants who had lost three or more lines of vision at 52 weeks in three interferon alfa-2a groups versus placebo. The results show an odds ratio of 1.60 (95% Confidence Interval 1.01 to 2.53) indicating that interferon is associated with a 60% increased odds of losing three or more lines at 52 weeks. This finding is marginally statistical with a P value of 0.04 and indicates that the treatment has the potential for harm rather than benefit.

AUTHORS' CONCLUSIONS

At present there is not enough evidence to recommend the use of interferon alfa-2a for the treatment of age-related macular degeneration.

In vitro sealing of punctured fetal membranes: potential treatment for midtrimester premature rupture of membranes

OBJECTIVE

Midtrimester premature rupture of membranes causes significant perinatal morbidity and death. No effective treatment exists. We investigated (1) whether a needle puncture in the fetal membranes could be sealed in vitro and (2) the optimal composition of the sealant to be used.

STUDY DESIGN

Membranes from second trimester pregnancies (16-24 weeks of gestation) were stretched over a modified syringe with a 2.5-cm open diameter. The syringe was filled with 20 mL of second trimester amniotic fluid, and the membrane was punctured with a 20-gauge needle. Sealants were injected into the amniotic fluid. The primary outcome variable was time for leakage of amniotic fluid. Median times for leakage for the formulations were compared by Wilcoxon exact rank sum test.

RESULTS

Platelets alone failed to seal the puncture site. All other formulations stopped leakage temporarily. Tisseel (Baxter Corp, Glendale, Calif) and cryoprecipitate/thrombin preparations led to more prolonged sealing of punctured amniotic membranes than platelets (P <.01) and were not significantly different from each other.

CONCLUSION

Of the sealants tested in vitro, amniotic membranes are best sealed by a fibrin/thrombin-based sealant.

Does transvaginal ultrasound of the cervix predict preterm premature rupture of membranes in a high-risk population?

OBJECTIVES

To determine in patients with a cervical length < 25 mm on transvaginal ultrasound if the severity of cervical length shortening can be used to predict preterm premature rupture of membranes (PPROM) and the contribution of PPROM to preterm delivery in these patients.

METHODS

We retrospectively reviewed asymptomatic singleton pregnancies between 14 and 24 weeks at high risk of preterm delivery by obstetric history and transvaginal cervical length < 25 mm. Cases developing subsequent PPROM were compared with controls for transvaginal sonographic cervical characteristics.

RESULTS

Of 69 patients identified to have a cervical length < 25 mm, 27 (39%) had PPROM, and 42 (61%) did not. Mean +/- standard deviation (SD) cervical length was 12.7 +/- 8.7 mm and 17.0 +/- 7.6 mm in the two groups, respectively (P = 0.04). Mean +/- SD cervical funneling was 57.4 +/- 31.4% and 40.0 +/- 28.1%, respectively (P = 0.01). The characteristics most predictive of PPROM were: cervical length of < 10 mm (sensitivity, specificity, positive and negative predictive values of 33, 90, 69, and 68%, respectively; odds ratio, 4.8; 95% confidence interval, 1.3-17.5) and cervical funneling > 75% (sensitivity, specificity, positive and negative predictive values of 33, 93, 75 and 68%, respectively; odds ratio, 6.5; 95% confidence interval, 1.6-26.9). Stepwise logistic regression revealed cervical length to be a significant predictor of PPROM (odds ratio, 4.0; 95% confidence interval, 1.1-14.2).

CONCLUSION

In patients at high risk for preterm delivery because of obstetric history and transvaginal sonographic cervical length < 25 mm, a cervical length < 10 mm and cervical funneling > 75% were most predictive of PPROM. PPROM was the major contributor to preterm delivery in these patients.

Population adjustment of the definition of the vaginal birth after cesarean rate

OBJECTIVE

The vaginal birth after cesarean delivery rate is calculated with a denominator equal to the number of all women who give birth after a previous cesarean delivery, including those who are not candidates for a trial of labor. We evaluated the impact of adjustment for noncandidates for a trial of labor on vaginal birth after cesarean delivery rates.

STUDY DESIGN

All women with a previous cesarean delivery who were delivered during 1998 were classified as either candidates or noncandidates for a trial of labor. An adjusted vaginal birth after cesarean delivery rate was calculated by eliminating noncandidates for a trial of labor from the denominator. The percentage of noncandidates for a trial of labor, the vaginal birth after cesarean delivery rate, and the adjusted vaginal birth after cesarean delivery rate were compared among 3 clinical services.

RESULTS

The maternal-fetal medicine service had a significantly higher percentage of noncandidates for a trial of labor than did either the low-risk resident clinic or the low-risk private service. The maternal-fetal medicine service had a significantly lower vaginal birth after cesarean delivery rate than did the private service, but this difference was no longer present after application of an adjusted vaginal birth after cesarean delivery definition.

CONCLUSION

For accurate comparison of vaginal birth after cesarean delivery rates among providers it is essential to account for patient risk status in the vaginal birth after cesarean delivery definition through the elimination of noncandidates for a trial of labor.

Evaluation of trovafloxacin in the treatment of Klebsiella pneumoniae lung infection in tumour-bearing mice

Trovafloxacin, a new trifluoroquinolone, was evaluated for its therapeutic efficacy against Klebsiella pneumoniae lung infection in tumour (P388 murine leukaemia cells)-bearing mice, treated with or without a chemotherapeutic agent, daunorubicin (DNR) and in mice without tumour. Its activity was compared with ciprofloxacin and cephazolin. The effect on therapeutic efficacy of the addition of recombinant granulocyte colony stimulating factor (rGCSF) was also examined. Our study showed that both quinolones successfully cured pneumonia owing to infection with K. pneumoniae in mice without tumours but that all antibiotics failed in tumour-bearing mice if DNR was withheld. Substantial differences were noted in DNR-treated tumour-bearing mice with infection-the cure rate with trovafloxacin was 91% whereas the cure rate with ciprofloxacin or cephazolin was 57%. Addition of rGCSF to ciprofloxacin did not substantially improve its efficacy (when assessed by protection against death owing to infection; the survival rate was 41%). Trovafloxacin cure rates ranged from 80 to 90% whether or not rGCSF was added to the treatment regimen. Our results suggest that prior cancer chemotherapy had no adverse effect on the therapeutic efficacy of trovafloxacin, and that trovafloxacin may be a promising therapeutic agent for treatment of bacterial infections in the presence of leucopenia.

Efficacy of trovafloxacin for treatment of experimental Bacteroides infection in young and senescent mice

We investigated the efficacy of trovafloxacin, a new quinolone, in comparison with that of clindamycin in the treatment of intra-abdominal abscesses caused by Bacteroides fragilis in young and senescent mice. The development of abscess formation, the number of viable organisms, and antibiotic concentrations were measured, and the values for young and old mice were compared. Trovafloxacin was well distributed to the tissues in both young and old animals. Although the pharmacokinetics and concentrations of trovafloxacin in serum were similar between young and old mice, the levels in tissue were higher in senescent mice than in young mice. Trovafloxacin therapy sterilized abscesses in 94% of young mice and in 73% of old mice, but this difference was not significant. This therapeutic response to trovafloxacin was similar to that seen with clindamycin. These results suggest that aging may not have any adverse effect on the therapeutic outcome for intra-abdominal abscesses caused by B. fragilis.

In vivo efficacy of trovafloxacin (CP-99,217), a new quinolone, in experimental intra-abdominal abscesses caused by Bacteroides fragilis and Escherichia coli

The efficacy of trovafloxacin in treating Bacteroides fragilis and Escherichia coli infections was investigated and compared to the efficacy of combined clindamycin and gentamicin therapy in an experimental model of intra-abdominal abscesses in rats. Rats were treated with different doses of CP-116,517-27, a parenteral prodrug of trovafloxacin. Response to treatment was evaluated by mortality rate and elimination of infection (cure rate). Mortality in the control group was 85.4%, whereas in rats treated with trovafloxacin, it was close to 0%. The highest cure rate (89.3%) resulted from the administration of 40 mg of CP-116,517-27 per kg of body weight three times a day (TID) for 10 days (equivalent to 18.15 mg of active drug trovafloxacin per rat per day). The therapeutic response with trovafloxacin was comparable to that of a combination therapy of clindamycin (75 mg/kg) plus gentamicin (20 mg/kg) TID (cure rate, 74%; mortality rate, 5%). The measured peak levels of trovafloxacin in serum and abscess pus were 2.6 +/- 0.3 and 5.2 micrograms/ml, respectively. The tumor necrosis factor alpha levels in the untreated animals were high compared to those for rats treated with trovafloxacin or clindamycin plus gentamicin. These results demonstrate that trovafloxacin as a single agent appears to be as successful as clindamycin plus gentamicin in the treatment of experimental intra-abdominal abscesses in rats.

Differentiating lymphocytic adenohypophysitis from pituitary adenoma in the peripartum patient

Lymphocytic adenohypophysitis (LAH) is an autoimmune disorder of the pituitary gland with a predilection for the peripartum period and often mimics a pituitary adenoma. We sought to define the clinical, endocrinologic and radiographic characteristics differentiating peripartum LAH from pituitary adenoma to enable the use of noninvasive diagnosis and appropriate therapy. From published reports and our own case, the clinical histories and laboratory and radiographic studies of 45 patients fulfilling the diagnosis of peripartum LAH were reviewed. History of infertility or menstrual irregularity, symptomatology, endocrinologic evaluation, diagnostic imaging and associated medical conditions were analyzed. For comparison, 806 patients with pituitary adenoma and pregnancy from published series were evaluated. The spontaneous pregnancy rate in pituitary adenoma patients was 2.4% vs. 100% in LAH patients. Visual disturbances and headaches were significantly more frequent in patients with LAH. Prolactin levels were significantly lower in patients with LAH than in those with pituitary adenomas (34.6 +/- 46.3 [SD] vs. 393.0 +/- 300.4, P < .0001). Abnormalities in thyroid and/or adrenal function were also more common in patients with LAH (57.5% vs. 2.5%, P < .001). There were no distinguishing characteristics on radiographic studies. History and endocrinologic evaluation can differentiate between LAH and pituitary adenoma in the peripartum patient.

Cholelithiasis of the ovary

BACKGROUND

Laparoscopic cholecystectomy is becoming a popular surgical option in the management of gallstone disease. Reports on complications of this procedure have usually focused on prolonged operative time, bleeding, and infections. We describe a case of cholelithiasis of the ovary following laparoscopic cholecystectomy.

CASE

A 70-year-old woman, para 5-0-0-5, presented with a 2-month history of a pelvic mass following a laparoscopic cholecystectomy. Exploratory laparotomy demonstrated a 4 x 4-cm para-ovarian cyst as well as multiple rectal and pelvic implants. Pathologic findings confirmed gallstones of the ovary and pelvic peritoneum. These gallstones elicited mesothelial proliferation, local hemorrhage, and adhesion formation.

CONCLUSION

The pathologic consequences of pelvic cholelithiasis can be marked. This was demonstrated in a postmenopausal woman, but has direct implications for the premenopausal patient as well. Our experience suggests that gallstones lost during laparoscopic cholecystectomy should be removed if possible.

Fetal movement during labor

The prognostic significance of antepartum fetal movement is well known; therefore it may be a variable in intrapartum fetal well-being. We report the simultaneous observation of fetal movement with fetal heart rate and uterine contractions by processed Doppler actograph signals during spontaneous labor of 22 normal women with normal fetal outcome. The mean percent incidence of fetal movement during labor was 17.3%. The percentage occurring during uterine contractions was 65.9%. Of all uterine contractions, 89.8% were associated with fetal movement. The proportion of time the fetus spent moving during uterine contractions (21.4%) was higher than between uterine contractions (12.9%). Uterine contractions associated with fetal movement were significantly longer than those not associated with fetal movement (p less than 0.0001). Mean percent incidence of fetal movement did not differ significantly between latent and active-phase labor. This study demonstrates a clear relationship between fetal movement and uterine contractions in labor.

Chromatin and cell surface receptors mediate melanoma cell growth response to nerve growth factor

Growth response to nerve growth factor (NGF) was tested in the primary melanoma cell line WM 164, which expressed a low level of NGF cell-surface receptor, and in WM 164 cells transfected with cDNA for the cell-surface receptor (TrWM 164 cells), which expressed a higher level of the cell-surface receptor. Neither cell line expressed the chromatin receptor for NGF or internalized NGF. Both cell lines were stimulated to growth by NGF. After 10 d of exposure to NGF, a 230,000 Mr chromatin protein (receptor) was induced in both cell lines; as a result, NGF bound to the chromatin, and ribosomal RNA synthesis and cell proliferation were inhibited. We suggest that the cell-surface and chromatin receptors each mediate a different function of NGF.

Pyridoxal phosphate protects against an irreversible temperature-dependent inactivation of hepatic delta-aminolevulinic acid synthase

The stability of hepatic delta-aminolevulinic acid synthase (ALAS), the first and rate-limiting enzyme of the heme biosynthetic pathway, was investigated. Incubation of the mitochondrial matrix fraction obtained from either control or allylisopropylacetamide-induced rats at 37 degrees C in Tris-Cl, pH 7.4, EDTA, and dithiothreitol resulted in a rapid decrease in ALAS activity such that 50-70% of the activity was lost after 30 min. Similar decreases in ALAS activity were observed when a cytosolic fraction from the induced animals was incubated at 37 degrees C. Addition of 0.1 mM pyridoxal-P, the cofactor of ALAS, to the preincubation medium completely prevented the observed loss of activity; however, dialysis of the inactive matrix fraction against several changes of buffer containing pyridoxal-P did not restore activity, suggesting that the inactivation was irreversible. These decreases in ALAS activity in the absence of pyridoxal-P were temperature dependent, as a 55% loss of ALAS activity was observed after a 60-min incubation at 30 degrees C, while the enzyme was completely stable when preincubated at 22 degrees C for 60 min. This inactivation of ALAS does not appear to involve proteolytic digestion, as addition of a wide spectrum of protease inhibitors to the preincubation medium in the absence of pyridoxal-P did not protect against the inactivation. The suggestion is made that the cofactor, pyridoxal-P, may dissociate from the enzyme during the preincubation and, consequently, the apoenzyme may be irreversibly inactivated at temperatures above 22 degrees C.