External validation of prognostic models to predict stillbirth using International Prediction of Pregnancy Complications (IPPIC) Network database: individual participant data meta-analysis

OBJECTIVE

Stillbirth is a potentially preventable complication of pregnancy. Identifying women at high risk of stillbirth can guide decisions on the need for closer surveillance and timing of delivery in order to prevent fetal death. Prognostic models have been developed to predict the risk of stillbirth, but none has yet been validated externally. In this study, we externally validated published prediction models for stillbirth using individual participant data (IPD) meta-analysis to assess their predictive performance.

METHODS

MEDLINE, EMBASE, DH-DATA and AMED databases were searched from inception to December 2020 to identify studies reporting stillbirth prediction models. Studies that developed or updated prediction models for stillbirth for use at any time during pregnancy were included. IPD from cohorts within the International Prediction of Pregnancy Complications (IPPIC) Network were used to validate externally the identified prediction models whose individual variables were available in the IPD. The risk of bias of the models and cohorts was assessed using the Prediction study Risk Of Bias ASsessment Tool (PROBAST). The discriminative performance of the models was evaluated using the C-statistic, and calibration was assessed using calibration plots, calibration slope and calibration-in-the-large. Performance measures were estimated separately in each cohort, as well as summarized across cohorts using random-effects meta-analysis. Clinical utility was assessed using net benefit.

RESULTS

Seventeen studies reporting the development of 40 prognostic models for stillbirth were identified. None of the models had been previously validated externally, and the full model equation was reported for only one-fifth (20%, 8/40) of the models. External validation was possible for three of these models, using IPD from 19 cohorts (491 201 pregnant women) within the IPPIC Network database. Based on evaluation of the model development studies, all three models had an overall high risk of bias, according to PROBAST. In the IPD meta-analysis, the models had summary C-statistics ranging from 0.53 to 0.65 and summary calibration slopes ranging from 0.40 to 0.88, with risk predictions that were generally too extreme compared with the observed risks. The models had little to no clinical utility, as assessed by net benefit. However, there remained uncertainty in the performance of some models due to small available sample sizes.

CONCLUSIONS

The three validated stillbirth prediction models showed generally poor and uncertain predictive performance in new data, with limited evidence to support their clinical application. The findings suggest methodological shortcomings in their development, including overfitting. Further research is needed to further validate these and other models, identify stronger prognostic factors and develop more robust prediction models. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Neutrophil-Lymphocyte Ratio and Absolute Lymphocyte Count as Prognostic Markers in Patients Treated with Curative-intent Radiotherapy for Non-small Cell Lung Cancer

AIMS

The neutrophil-lymphocyte ratio (NLR) and the absolute lymphocyte count (ALC) have been proposed as prognostic markers in non-small cell lung cancer (NSCLC). The objective of this study was to examine the association of NLR/ALC before and after curative-intent radiotherapy for NSCLC on disease recurrence and overall survival.

MATERIALS AND METHODS

A retrospective study of consecutive patients who underwent curative-intent radiotherapy for NSCLC across nine sites in the UK from 1 October 2014 to 1 October 2016. A multivariate analysis was carried out to assess the ability of pre-treatment NLR/ALC, post-treatment NLR/ALC and change in NLR/ALC, adjusted for confounding factors using the Cox proportional hazards model, to predict disease recurrence and overall survival within 2 years of treatment.

RESULTS

In total, 425 patients were identified with complete blood parameter values. None of the NLR/ALC parameters were independent predictors of disease recurrence. Higher pre-NLR, post-NLR and change in NLR plus lower post-ALC were all independent predictors of worse survival. Receiver operator curve analysis found a pre-NLR > 2.5 (odds ratio 1.71, 95% confidence interval 1.06-2.79, P < 0.05), a post-NLR > 5.5 (odds ratio 2.36, 95% confidence interval 1.49-3.76, P < 0.001), a change in NLR >3.6 (odds ratio 2.41, 95% confidence interval 1.5-3.91, P < 0.001) and a post-ALC < 0.8 (odds ratio 2.86, 95% confidence interval 1.76-4.69, P < 0.001) optimally predicted poor overall survival on both univariate and multivariate analysis when adjusted for confounding factors. Median overall survival for the high-versus low-risk groups were: pre-NLR 770 versus 1009 days (P = 0.34), post-NLR 596 versus 1287 days (P ≤ 0.001), change in NLR 553 versus 1214 days (P ≤ 0.001) and post-ALC 594 versus 1287 days (P ≤ 0.001).

CONCLUSION

NLR and ALC, surrogate markers for systemic inflammation, have prognostic value in NSCLC patients treated with curative-intent radiotherapy. These simple and readily available parameters may have a future role in risk stratification post-treatment to inform the intensity of surveillance protocols.

A modified two-process Knox test for investigating the relationship between law enforcement opioid seizures and overdoses

Recent research has shown an association between monthly law enforcement drug seizure events and accidental drug overdose deaths using cross-sectional data in a single state, whereby increased seizures correlated with more deaths. In this study, we conduct statistical analysis of street-level data on law enforcement drug seizures, along with street-level data on fatal and non-fatal overdose events, to determine possible micro-level causal associations between opioid-related drug seizures and overdoses. For this purpose, we introduce a novel, modified two-process Knox test that controls for self-excitation to measure clustering of overdoses nearby in space and time following law enforcement seizures. We observe a small, but statistically significant ( p  < 0.001), effect of 17.7 excess non-fatal overdoses per 1000 law enforcement seizures within three weeks and 250 m of a seizure. We discuss the potential causal mechanism for this association along with policy implications.

Predicting the Risk of Disease Recurrence and Death Following Curative-intent Radiotherapy for Non-small Cell Lung Cancer: The Development and Validation of Two Scoring Systems From a Large Multicentre UK Cohort

AIMS

There is a paucity of evidence on which to produce recommendations on neither the clinical nor the imaging follow-up of lung cancer patients after curative-intent radiotherapy. In the 2019 National Institute for Health and Care Excellence lung cancer guidelines, further research into risk-stratification models to inform follow-up protocols was recommended.

MATERIALS AND METHODS

A retrospective study of consecutive patients undergoing curative-intent radiotherapy for non-small cell lung cancer from 1 October 2014 to 1 October 2016 across nine UK trusts was carried out. Twenty-two demographic, clinical and treatment-related variables were collected and multivariable logistic regression was used to develop and validate two risk-stratification models to determine the risk of disease recurrence and death.

RESULTS

In total, 898 patients were included in the study. The mean age was 72 years, 63% (562/898) had a good performance status (0-1) and 43% (388/898), 15% (134/898) and 42% (376/898) were clinical stage I, II and III, respectively. Thirty-six per cent (322/898) suffered disease recurrence and 41% (369/898) died in the first 2 years after radiotherapy. The ASSENT score (age, performance status, smoking status, staging endobronchial ultrasound, N-stage, T-stage) was developed, which stratifies the risk for disease recurrence within 2 years, with an area under the receiver operating characteristic curve (AUROC) for the total score of 0.712 (0.671-0.753) and 0.72 (0.65-0.789) in the derivation and validation sets, respectively. The STEPS score (sex, performance status, staging endobronchial ultrasound, T-stage, N-stage) was developed, which stratifies the risk of death within 2 years, with an AUROC for the total score of 0.625 (0.581-0.669) and 0.607 (0.53-0.684) in the derivation and validation sets, respectively.

CONCLUSIONS

These validated risk-stratification models could be used to inform follow-up protocols after curative-intent radiotherapy for lung cancer. The modest performance highlights the need for more advanced risk prediction tools.

Prediction of stillbirth: an umbrella review of evaluation of prognostic variables

BACKGROUND

Stillbirth accounts for over 2 million deaths a year worldwide and rates remains stubbornly high. Multivariable prediction models may be key to individualised monitoring, intervention or early birth in pregnancy to prevent stillbirth.

OBJECTIVES

To collate and evaluate systematic reviews of factors associated with stillbirth in order to identify variables relevant to prediction model development.

SEARCH STRATEGY

MEDLINE, Embase, DARE and Cochrane Library databases and reference lists were searched up to November 2019.

SELECTION CRITERIA

We included systematic reviews of association of individual variables with stillbirth without language restriction.

DATA COLLECTION AND ANALYSIS

Abstract screening and data extraction were conducted in duplicate. Methodological quality was assessed using AMSTAR and QUIPS criteria. The evidence supporting association with each variable was graded.

RESULTS

The search identified 1198 citations. Sixty-nine systematic reviews reporting 64 variables were included. The most frequently reported were maternal age (n = 5), body mass index (n = 6) and maternal diabetes (n = 5). Uterine artery Doppler appeared to have the best performance of any single test for stillbirth. The strongest evidence of association was for nulliparity and pre-existing hypertension.

CONCLUSION

We have identified variables relevant to the development of prediction models for stillbirth. Age, parity and prior adverse pregnancy outcomes had a more convincing association than the best performing tests, which were PAPP-A, PlGF and UtAD. The evidence was limited by high heterogeneity and lack of data on intervention bias.

TWEETABLE ABSTRACT

Review shows key predictors for use in developing models predicting stillbirth include age, prior pregnancy outcome and PAPP-A, PLGF and Uterine artery Doppler.

Effect of sildenafil on maternal hemodynamics in pregnancies complicated by severe early-onset fetal growth restriction: planned subgroup analysis from a multicenter randomized placebo-controlled double-blind trial

OBJECTIVES

Fetal growth restriction (FGR) is associated with maternal cardiovascular changes. Sildenafil, a phosphodiesterase type-5 inhibitor, potentiates the actions of nitric oxide, and it has been suggested that it alters maternal hemodynamics, potentially improving placental perfusion. Recently, the Dutch STRIDER trial was stopped prematurely owing to excess neonatal mortality secondary to pulmonary hypertension. The main aim of this study was to investigate the effect of sildenafil on maternal hemodynamics in pregnancies with severe early-onset FGR.

METHODS

This was a cardiovascular substudy within a UK multicenter, placebo-controlled trial, in which 135 women with a singleton pregnancy and severe early-onset FGR (defined as a combination of estimated fetal weight or abdominal circumference below the 10^th centile and absent/reversed end-diastolic flow in the umbilical artery on Doppler velocimetry, diagnosed between 22 + 0 and 29 + 6 weeks' gestation) were assigned randomly to receive either 25 mg sildenafil three times daily or placebo until 32 + 0 weeks' gestation or delivery. Maternal blood pressure (BP), heart rate (HR), augmentation index, pulse wave velocity (PWV), cardiac output, stroke volume (SV) and total peripheral resistance were recorded before randomization, 1-2 h and 48-72 h post-randomization, and 24-48 h postnatally. For continuous data, analysis was performed using repeated measures ANOVA methods including terms for timepoint, treatment allocation and their interaction.

RESULTS

Included were 134 women assigned randomly to sildenafil (n = 69) or placebo (n = 65) who had maternal BP and HR recorded at baseline. At 1-2 h post-randomization, compared with baseline values, sildenafil increased maternal HR by 4 bpm more than did placebo (mean difference, 5.00 bpm (95% CI, 1.00-12.00 bpm) vs 1.25 bpm (95% CI, -5.38 to 7.88 bpm); P = 0.004) and reduced systolic BP by 1 mmHg more (mean difference, -4.13 mmHg (95% CI, -9.94 to 1.44 mmHg) vs -2.75 mmHg (95% CI, -7.50 to 5.25 mmHg); P = 0.048). Even after adjusting for maternal mean arterial pressure, sildenafil reduced aortic PWV by 0.60 m/s more than did placebo (mean difference, -0.90 m/s (95% CI, -1.31 to -0.51 m/s) vs -0.26 m/s (95% CI, -0.75 to 0.59 m/s); P = 0.001). Sildenafil was associated with a non-significantly greater decrease in SV index after 1-2 h post-randomization than was placebo (mean difference, -5.50 mL/m² (95% CI, -11.00 to -0.50 mL/m² ) vs 0.00 mL/m² (95% CI, -5.00 to 4.00 mL/m² ); P = 0.056).

CONCLUSIONS

Sildenafil in a dose of 25 mg three times daily increases HR, reduces BP and reduces arterial stiffness in pregnancies complicated by severe early-onset FGR. These changes are short term, modest and consistent with the anticipated vasodilatory effect. They have no short- or long-term clinical impact on the mother. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Impact of ethnicity on adverse perinatal outcome in women with chronic hypertension: a cohort study

OBJECTIVE

To assess the impact of maternal ethnicity on the risk of adverse perinatal outcome in pregnant women with chronic hypertension.

METHODS

Demographic and delivery data were collated of women with chronic hypertension and singleton pregnancy who delivered at one of three UK obstetric units between 2000 and 2014. Multivariable logistic regression models were used to calculate risk ratios (RR), according to ethnic group, for adverse perinatal outcome, adjusted for other maternal characteristics including age, parity, body mass index, smoking status, deprivation index and year of delivery. The impact of maternal ethnicity on birth-weight centile calculation was investigated by comparing the birth-weight centile chart customized for ethnicity (Gestation Related Optimal Weight; GROW) with a birth-weight centile calculator that does not adjust for that factor (INTERGROWTH-21^st ).

RESULTS

The study cohort included 4481 pregnancies (4045 women) with chronic hypertension. Women of white ethnicity accounted for 47% (n = 2122) of the cohort and 36% (n = 1601) were of black, 8.5% (n = 379) of Asian and 8.5% (n = 379) of other ethnicity. The overall incidence of stillbirth was 1.6%, that of preterm birth < 37 weeks was 16% and that of fetal growth restriction (birth weight < 3^rd centile) was 11%. Black women, compared with white women, had the highest risk for all adverse perinatal outcomes, with stillbirth occurring in 3.1% vs 0.6% of pregnancies (adjusted RR (aRR), 5.56 (95% CI, 2.79-11.09)), preterm birth < 37 weeks in 21% vs 11% (aRR, 1.70 (95% CI, 1.43-2.01)) and birth weight < 3^rd centile in 15% vs 7.4% (aRR, 2.07 (95% CI, 1.71-2.51)). Asian women, compared with white women, were also at increased risk of adverse perinatal outcome, with stillbirth occurring in 1.6% vs 0.6% (aRR, 3.03 (95% CI, 1.11-8.28)), preterm birth < 37 weeks in 20% vs 11% (aRR, 1.82 (95% CI, 1.41-2.35)) and birth weight < 3^rd centile in 12% vs 7.4% (aRR, 1.69 (95% CI, 1.24-2.30)). The sensitivity and specificity for prediction of infants requiring neonatal unit admission were 40% and 93%, respectively, for those with birth weight < 3^rd centile according to GROW charts, compared with 16% and 96%, respectively, for those with birth weight < 3^rd centile according to INTERGROWTH-21^st charts.

CONCLUSIONS

Black ethnicity, compared with white, is associated with the greatest risk of adverse perinatal outcome in women with chronic hypertension, even after adjusting for other maternal characteristics. Women of Asian ethnicity are also at increased risk, but to a lesser extent. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

A pilot interventional study to evaluate the impact of cholecalciferol treatment on HbA1c in type 1 diabetes (T1D)

BACKGROUND

Higher 25(OH)D3 levels are associated with lower HbA1c, but there are limited UK interventional trials assessing the effect of cholecalciferol on HbA1c.

AIMS

(1) To assess the baseline 25(OH)D3 status in a Manchester cohort of children with type 1 diabetes (T1D). (2) To determine the effect of cholecalciferol administration on HbA1c.

METHODS

Children with T1D attending routine clinic appointments over three months in late winter/early spring had blood samples taken with consent. Participants with a 25(OH)D3 level <50 nmol/L were treated with a one-off cholecalciferol dose of 100,000 (2-10 years) or 160,000 (>10 years) units. HbA1c levels before and after treatment were recorded.

RESULTS

Vitamin D levels were obtained from 51 children. 35 were Caucasian, 11 South Asian and 5 from other ethnic groups. 42 were vitamin D deficient, but 2 were excluded from the analysis. All South Asian children were vitamin D deficient, with mean 25(OH)D3 of 28 nmol/L. In Caucasians, there was a negative relationship between baseline 25(OH)D3 level and HbA1c (r = -0.484, P < 0.01). In treated participants, there was no significant difference in mean HbA1c at 3 months (t = 1.010, P = 0.328) or at 1 year (t = -1.173, P = 0.248) before and after treatment. One-way ANCOVA, controlling for age, gender, ethnicity, BMI and diabetes duration showed no difference in Δ HbA1c level.

CONCLUSION

We report important findings at baseline, but in children treated with a stat dose of cholecalciferol, there was no effect on HbA1c. Further studies with larger sample sizes and using maintenance therapy are required.

Clinical effectiveness and cost-effectiveness of endobronchial and endoscopic ultrasound relative to surgical staging in potentially resectable lung cancer: results from the ASTER randomised controlled trial

OBJECTIVE

To assess the clinical effectiveness and cost-effectiveness of endosonography (followed by surgical staging if endosonography was negative), compared with standard surgical staging alone, in patients with non-small cell lung cancer (NSCLC) who are otherwise candidates for surgery with curative intent.

DESIGN

A prospective, international, open-label, randomised controlled study, with a trial-based economic analysis.

SETTING

Four centres: Ghent University Hospital, Belgium; Leuven University Hospitals, Belgium; Leiden University Medical Centre, the Netherlands; and Papworth Hospital, UK.

PARTICIPANTS

INCLUSION CRITERIA

known/suspected NSCLC, with suspected mediastinal lymph node involvement; otherwise eligible for surgery with curative intent; clinically fit for endosonography and surgery; and no evidence of metastatic disease.

EXCLUSION CRITERIA

previous lung cancer treatment; concurrent malignancy; uncorrected coagulopathy; and not suitable for surgical staging.

INTERVENTIONS

Study patients were randomised to either surgical staging alone (n = 118) or endosonography followed by surgical staging if endosonography was negative (n = 123). Endosonography diagnostic strategy used endoscopic ultrasound-guided fine-needle aspiration combined with endobronchial ultrasound-guided transbronchial needle aspiration, followed by surgical staging if these tests were negative. Patients with no evidence of mediastinal metastases or tumour invasion were referred for surgery with curative intent. If evidence of malignancy was found, patients were referred for chemoradiotherapy.

MAIN OUTCOME MEASURES

The main clinical outcomes were sensitivity (positive diagnostic test/nodal involvement during any diagnostic test or thoracotomy) and negative predictive value (NPV) of each diagnostic strategy for the detection of N2/N3 metastases, unnecessary thoracotomy and complication rates. The primary economic outcome was cost-utility of the endosonography strategy compared with surgical staging alone, up to 6 months after randomisation, from a UK NHS perspective.

RESULTS

Clinical and resource-use data were available for all 241 patients, and complete utilities were available for 144. Sensitivity for detecting N2/N3 metastases was 79% [41/52; 95% confidence interval (CI) 66% to 88%] for the surgical arm compared with 94% (62/66; 95% CI 85% to 98%) for the endosonography strategy (p = 0.02). Corresponding NPVs were 86% (66/77; 95% CI 76% to 92%) and 93% (57/61; 95% CI 84% to 97%; p = 0.26). There were 21/118 (18%) unnecessary thoracotomies in the surgical arm compared with 9/123 (7%) in the endosonography arm (p = 0.02). Complications occurred in 7/118 (6%) in the surgical arm and 6/123 (5%) in the endosonography arm (p = 0.78): one pneumothorax related to endosonography and 12 complications related to surgical staging. Patients in the endosonography arm had greater EQ-5D (European Quality of Life-5 Dimensions) utility at the end of staging (0.117; 95% CI 0.042 to 0.192; p = 0.003). There were no other significant differences in utility. The main difference in resource use was the number of thoracotomies: 66% patients in the surgical arm compared with 53% in the endosonography arm. Resource use was similar between the groups in all other items. The 6-month cost of the endosonography strategy was £9713 (95% CI £7209 to £13,307) per patient versus £10,459 (£7732 to £13,890) for the surgical arm, mean difference £746 (95% CI -£756 to £2494). The mean difference in quality-adjusted life-year was 0.015 (95% CI -0.023 to 0.052) in favour of endosonography, so this strategy was cheaper and more effective.

CONCLUSIONS

Endosonography (followed by surgical staging if negative) had higher sensitivity and NPVs, resulted in fewer unnecessary thoracotomies and better quality of life during staging, and was slightly more effective and less expensive than surgical staging alone. Future work could investigate the need for confirmatory mediastinoscopy following negative endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) and endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), the diagnostic accuracy of EUS-FNA or EBUS-TBNA separately and the delivery of both EUS-FNA or EBUS-TBNA by suitably trained chest physicians.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN 97311620.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 16, No. 18. See the HTA programme website for further project information.

PP164. Magnesium sulphate for prevention and treatment of eclampsia in low and middle income countries: Systematic review of tested regimens

INTRODUCTION

Magnesium sulphate (MgSO4) is regarded as the most effective prophylactic and therapeutic agent for eclampsia. Although well studied and widely used in high income countries (HICs), MgSO4 is under utilized in low and middle income countries (LMICs) due to many factors including lack of adequately trained health care providers, supplies for administration, or the MgSO4 itself, in addition to fear of potential adverse effects.

OBJECTIVES

To systematically review the dosing and effectiveness of MgSO4 regimens administered in LMICs to women with pre-eclampsia or eclampsia.

METHODS

We searched Medline, EMBASE, IPA, CINAHL, CDSR and CENTRAL databases for English language randomized controlled trials (RCT) and observational studies of MgSO4 regimens administered in LMICs to women with pre-eclampsia or eclampsia. Two authors independently reviewed search results and extracted relevant data from eligible studies. No quality assessment was performed.

RESULTS

Twenty two papers (7 RCT and 15 observational studies) from 12 LMIC met our inclusion criteria, of which 21 were conducted in hospital settings. Two studied MgSO4 for eclampsia prevention ,14 for eclampsia treatment and 6 studied MgSO4 for both. In 20 studies, both loading and maintenance MgSO4 dosing was administered, with intravenous (IV) or combined IV and intramuscular (IM) loading doses of 4-15g and IV or IM maintenance doses up to 2g/h. Five studies used only the IV route of administration, while the remainder coupled IV with IM administration. All studies were effective at preventing the initiation and/or recurrence of eclamptic seizures. One study of 265 women with eclampsia found that MgSO4 loading dose administration in the community (4g IV over 20min plus 3g IM in each buttock) before referral and administration of maintenance therapy in hospital was more effective in decreasing recurrent eclampsia compared with the standard practice of referral to hospital where the initial dose of MgSO4 was administered [RR of 0.23, 95% CI 0.11, 0.49]. The two studies of 4g IV plus 10g IM loading dose-only regimens did not show a significant reduction in eclamptic seizures compared with identical loading dose plus 5g/4h IM maintenance dose regimens [RR of 1.38, 95% CI of 0.23, 8.45]. However the combined sample size was small (N=180 women).

CONCLUSION

In LMICs, most studies of MgSO4 for pre-eclampsia or eclampsia were conducted in high level health care facilities and administered MgSO4 by the IV route, at least in part. The one study of community administration of a MgSO4 loading dose showed this approach to be effective. There are limited data to support loading dose-only regimens.

Prevention and treatment of postpartum hypertension

BACKGROUND

Postpartum blood pressure (BP) is highest three to six days after birth when most women have been discharged home. A significant rise in BP may be dangerous (e.g., lead to stroke), but there is little information about how to prevent or treat postpartum hypertension.

OBJECTIVES

To assess the relative benefits and risks of interventions to: (1) prevent postpartum hypertension, by assessing whether 'routine' postpartum administration of oral antihypertensive therapy is better than placebo/no treatment; and(2) treat postpartum hypertension, by assessing whether (i) oral antihypertensive therapy is better than placebo/no therapy for mild-moderate postpartum hypertension; and (ii) one antihypertensive agent offers advantages over another for mild-moderate or severe postpartum hypertension.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register (March 2004), MEDLINE (1966 to May 2003), EMBASE (1980 to January 2003), bibliographies of retrieved papers and personal files.

SELECTION CRITERIA

For women with antenatal hypertension, trials comparing a medical intervention with placebo/no therapy. For women with postpartum hypertension, trials comparing one antihypertensive with either another or placebo/no therapy.

DATA COLLECTION AND ANALYSIS

We extracted the data independently and were not blinded to trial characteristics or outcomes. We contacted authors for missing data when possible.

MAIN RESULTS

Six trials are included.

PREVENTION

Three trials (315 women; six comparisons) compared furosemide or nifedipine capsules with placebo/no therapy. There are insufficient data for conclusions about possible benefits and risks of these management strategies. Most outcomes included data from only one trial. No trial reported severe maternal hypertension or breastfeeding.

TREATMENT

In two trials (106 women; three comparisons), oral timolol or hydralazine were compared with oral methyldopa for treatment of mild to moderate postpartum hypertension. In one trial (38 women; one comparison), oral hydralazine plus sublingual nifedipine were compared with sublingual nifedipine for treatment of severe postpartum hypertension. The need for additional antihypertensive therapy did not differ between groups (relative risk 4.24, 95% confidence interval 0.96 to 18.84; three trials, N = 144 women), but three antihypertensive drugs were studied. All were well tolerated.

AUTHORS' CONCLUSIONS

There are no reliable data to guide management of women who are hypertensive postpartum or at increased risk of becoming so. If a clinician feels that hypertension is severe enough to treat, the agent used should be based on his/her familiarity with the drug. Future studies of prevention or treatment of postpartum hypertension should include information about use of postpartum analgesics and outcomes of severe maternal hypertension, breastfeeding, hospital length of stay, and maternal satisfaction with care.

Nausea and vomiting in pregnancy: results of a survey that identified interventions used by women to alleviate their symptoms

Nausea and vomiting of pregnancy (NVP) affects most pregnant women. There are safe and effective treatments available; however, most women choose to avoid pharmacological therapies and try lifestyle and dietary changes to treat their condition. To date, no attempt has been made to quantify women's experience with a variety of interventions. This study aims to identify factors commonly reported by women that alleviate their symptoms of NVP. Five hundred women with NVP, calling a pregnancy healthline between February 1996 and July 1999, completed a questionnaire where they were asked to rate which of 21 factors helped and to what extent each factor helped to improve their NVP symptoms. For each item, the 'frequency' (percentage of women who indicated that item as an improvement) and 'mean importance' (mean importance score of women who indicated that item as an improvement) were multiplied to give the 'overall impact' score. All 500 women reported that dietary and lifestyle changes helped to improve their NVP symptoms. However, most items were rated low and only 31% of women reported benefit from the use of pharmacological treatment. In conclusion, this study has identified that NVP is a multifaceted condition. Lifestyle changes including validation, supportive counseling and dietary adjustments are important components, that can be used to counsel women with NVP, concomitantly with safe and effective treatment.

The effects of creatine dietary supplementation on anterior compartment pressure in the lower leg during rest and following exercise

OBJECTIVE

To examine the effects of creatine supplementation on anterior compartment pressure of the lower leg at rest and following exercise.

DESIGN

14 college-age males received creatine or placebo supplementation for 34 days. At baseline, anterior compartment pressure was measured preexercise, immediately postexercise, and 1, 5, and 15 minutes postexercise after a level treadmill run for 20 minutes at 80% of maximal aerobic power.

INTERVENTION

Following baseline testing, subjects began a 6-day creatine or placebo loading phase at a dosage of 0.3 g x kg body mass(-1) x d(-1). This was followed by a 28-day maintenance phase at a dosage of 0.03 g x kg body mass(-1) x d(-1). Subjects and investigators were blinded as to treatment administration. Subjects continued to exercise during the supplementation period. After 6 days and 34 days of supplementation. anterior compartment pressure was measured at rest and following exercise.

RESULTS

Creatine supplementation for 6 days significantly increased compartment pressure compared with the placebo group at rest (76%), immediately post- (150%), 1 minute post- (125%), 5 minute post- (106%), and 15 minute postexercise (77%). Anterior compartment pressures continued to remain significantly higher for the creatine group compared with the placebo group at rest (72%), immediately post- (125%) and 1 minute postexercise (180%) after 34 days of creatine supplementation.

CONCLUSIONS

These data indicate that creatine supplementation abnormally increases anterior compartment pressure in the lower leg at rest and following 20 minutes of level running at 80% of maximal aerobic power.

A novel method for the evaluation of the severity of nausea and vomiting of pregnancy

The symptomatology of nausea and vomiting of pregnancy (NVP) ranges from mild to very severe. The most advanced method to measure the burden of NVP, the Rhode's scores, incorporates physical signs (length and number of episodes of nausea, number and volume of vomits, and number of retching) with measures of distress caused by these symptoms. However, this system has been validated only for symptoms that occurred in the past 12 h, thus obviating its wide clinical use, and particularly its retrospective use.

OBJECTIVE

To examine whether the severity of the physical symptoms of NVP correlate with the degree of stress caused by them, and to develop simple scores that can be used clinically.

METHODS AND RESULTS

We prospectively scored 283 women with NVP using the Rhode's system. There was excellent and highly significant correlation between the physical symptoms and their degrees of distress. Subsequently, we examined two simple scoring systems, one with three and one with five physical symptoms. Both yielded distribution of severity of NVP not different from the one found with the use of the full Rhode's score.

CONCLUSION

A scoring system based on all five physical symptoms, or only on three (length of nausea, number of episodes of nausea and number of vomits) yielded accurate estimates of severity and changes in severity of NVP. Unlike the Rhode's score, this simple method can be used clinically to evaluate the severity and changes in NVP.

Pharmacologic treatment of nausea and vomiting during pregnancy

QUESTIONSome of my pregnant patients have trouble functioning because of morning sickness. In particular, they are afraid to take medications. They end up losing weight, quitting work, and dropping out of other activities. What can I do to allay their fears?ANSWERWomen often benefit from knowing that they are not alone in having this problem, that morning sickness typically does not harm a fetus, and that safe therapies are available. Psychological and medical support is very important. Other causes of nausea and vomiting must always be ruled out. The Motherisk Program has a clinic and hot-line line for patients with severe morning sickness.

Acid-suppressing drugs during pregnancy

Images

Tea drinking and haemostasis: a randomized, placebo-controlled, crossover study in free-living subjects

The hypothesis that tea drinking may protect against coronary heart disease (CHD) through effects on clotting as measured by plasma fibrinogen, tissue-type plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1) was tested in 65 healthy volunteers (31 men and 34 women; aged 20-74 years) in a randomized, blind, placebo-controlled, crossover study lasting 10 weeks (run-in phase 2 weeks, tea and placebo phases 4 weeks). During the placebo phase, intakes of milk, sugar, water and caffeine were matched to those in the tea phase during which 6 mugs of tea were drunk daily. Compliance with tea intake was measured by marking tea bags with p-aminobenzoic acid and measuring recovery in 24-hour urine collections. The mean +/- SD fibrinogen level, PAI-1 activity and tPA antigen level at baseline of 2.91 +/- 0.81 g/l, 7.9 +/- 5.3 U/ml and 4.76 +/- 2.17 ng/ml, respectively, were in the normal range. No significant differences in these variables between the run-in, tea or placebo phases were observed. The putative protective effect of tea against development of CHD is not mediated through effects of black tea on fibrinogen, tPA or PAI-1.

Anaesthetic drugs and bacterial contamination

We investigated the bacterial contamination of commonly used intravenous anaesthetic agents. Ten trainee anaesthetists drew up four syringes each of propofol, midazolam, thiopentone, 0.9% saline and a culture medium control using their normal practice. A set of syringes was cultured at the time of drawing up and at 2, 4 and 8 h afterwards. No anaesthetist washed his or her hands before drawing up the drugs. Six anaesthetists capped the syringes using sheathed needles. Eight syringes were contaminated with bacteria. Coagulase-negative staphylococci were isolated from six syringes (four sheathed and two unsheathed) and an Acinetobacter sp. from two syringes (one sheathed and one unsheathed). No bacteria were cultured from the midazolam syringes. However, two syringes from each of the other solutions were contaminated. This implies that one syringe was contaminated when it was drawn up, at 2 h a further two had detectable contamination, two more were contaminated at 4 h and three more at 8 h. We cannot recommend drawing up drugs at the start of a list for use later in the day. They should be used immediately after drawing up. Basic hand washing before drawing up drugs may reduce contamination.

Propofol versus propofol with midazolam for laryngeal mask insertion

We evaluated the addition of midazolam to propofol during induction of anaesthesia by assessing laryngeal mask tolerance, haemodynamic variables, recovery times and cost. Forty patients (ASA grades I-IV) undergoing elective surgery were allocated randomly to receive a standard dose of propofol or a smaller dose of propofol combined with midazolam. A laryngeal mask was inserted and any episodes of coughing or hiccuping during its insertion or removal were recorded. Anaesthesia was maintained with nitrous oxide and enflurane with fentanyl for analgesia. After surgery, recovery times, pain, shivering, nausea, vomiting and analgesic requirements were recorded. The cost of the drugs used was also calculated. No significant differences were detected in any variables, except that patients given propofol needed more morphine in the recovery ward. The average cost of propofol alone was 3.47 pounds per anaesthetic, while the midazolam plus propofol cost was 2.03 pounds. Adding midazolam to propofol allowed a reduced dose of propofol to be used without adverse effects, while reducing the anaesthetic costs.

Musculoskeletal injuries in a college-age population during a 1-semester term

The authors' retrospective survey assessed the incidence and causes of sport- and exercise-related injuries in college students participating in intramural, recreational, and club sports. For their survey, they examined clinical screening forms and medical charts of 300 students (160 men and 140 women) to determine the type of injury, the body part affected, loading behavior of tissues involved, and mechanism of the injuries. Sprains resulting from tensile forces accounted for most of the injuries, with the knee the most frequently injured body part. The occurrence of injuries was equally divided between injuries from overuse, caused primarily by improper body mechanics, and acute injuries resulting from collisions with the ground or floor or from falls. The study suggests a need for programs in sport-injury prevention for college students.

Drug therapy for fetal arrhythmias

Diagnosis of specific types of fetal arrhythmias, especially tachyarrhythmias, is still difficult, often making semi-blind treatment inevitable. Published reports of many experienced clinicians show that digoxin remains a mainstream drug for therapy for fetal SVT and AF; digoxin is used as an initial monotherapy or in combination with other drugs if unresponsive to digoxin alone. It remains to be evaluated whether this treatment strategy offers overall better clinical outcomes than other approaches. Verapamil and propranolol are used in combination with digoxin, although successful control by propranolol seems rare. Quinidine and procainamide reportedly are effective in some cases. Reports on successful outcomes of flecainide therapy have emerged recently, although possible negative inotropic actions are of concern. Amiodarone is effective in some cases with incessant tachycardias, but risks of fetal thyroid dysfunction preclude its use as a firstline drug in uncomplicated fetal SVT cases. Empiric findings still prevail in the area of fetal drug therapy for arrhythmias, especially tachycardias. Heterogeniety of the conditions, lack of comparative studies, and difficulty in monitoring fetal drug level, let alone unbound drug concentrations, further complicate assessment of efficacy of different modes of treatment. Problems identified throughout this review have yet to be solved. Despite all these uncertain factors, however, it is clear that no one can undermine never-ending efforts of many clinicians in this exciting field of medicine.

Alcohol and anxiety: ethopharmacological approaches

1. Anxiety reduction may be a mechanism in many of the behavioral problems associated with alcohol intake, including abuse, addiction, aggression, and impulsivity. 2. New "ethoexperimental" models of anxiety measure natural antipredator defensive behaviors. These include flight, freezing, and defensive threat and attack to discrete, present, threat stimuli; a pattern of risk assessment behaviors to potential threat; proximic avoidance and inhibition of nondefensive behaviors to both present and potential threat; and antipredator alarm vocalizations in a social situation when concealment is possible. 3. Alcohol reduces freezing, behavioral inhibition, and proximic avoidance. It increases risk assessment from a freezing baseline and decreases it from a movement (risk assessment) baseline. It has a biphasic effect on defensive attack, increasing it at low doses, but decreasing it at high doses. Alcohol has little or no effect on flight, defensive threat, and antipredator ultrasound. 4. The effects of alcohol on behavioral inhibition, proximic avoidance, and risk assessment from either a freezing or a movement baseline are identical to those of the classic anxiolytic, diazepam. However, alcohol appears to impact several defensive behaviors not influenced by diazepam. 5. These results provide considerable support for an anxiolytic interpretation of alcohol effects, but suggest that alcohol may have additional effects than those on anxiety mechanisms.

Attenuation of antipredator defensive behavior in rats following chronic treatment with imipramine

The anxiety/defense test battery has been developed to assess defensive reactions in rats to situations associated with a natural predator, the domestic cat. This comprises three paradigms designed to study the effects of cat exposure on general activity and location with respect to the cat (proxemic avoidance), the effects of cat exposure on non-defensive consummatory behavior, and the behavioral response to cat odor. In the present study subjects were exposed to 21 days pretreatment with imipramine (0, 5, and 15 mg/kg), before being assessed in the three experimental paradigms (carried out over a total period of 7 days). Imipramine treatment was maintained on a daily basis during the 7 days taken to complete the series of tests. The data indicated a behaviorally specific profile consistent with anxiety/fear reduction, but not with sedation, in three different paradigms, following treatment with 15 mg/kg imipramine. These behavioral changes included a reduction in freezing, proxemic avoidance and a disinhibition of suppressed feeding in response to cat presentation. Similarly, imipramine treatment (15 mg/kg) significantly reduced behaviors associated with risk assessment (e.g. flat back approach, stretch attend) during presentation of a cat odor stimulus. This behavioral profile suggests that chronic pretreatment with imipramine produces an attenuation of antipredator defensive behavior.

How should Fitts' Law be applied to human-computer interaction?

The paper challenges the notion that any Fitts' Law model can be applied generally to human-computer interaction, and proposes instead that applying Fitts' Law requires knowledge of the users' sequence of movements, direction of movement, and typical movement amplitudes as well as target sizes. Two experiments examined a text selection task with sequences of controlled movements (point-click and point-drag). For the point-click sequence, a Fitts' Law model that used the diagonal across the text object in the direction of pointing (rather than the horizontal extent of the text object) as the target size provided the best fit for the pointing time data, whereas for the point-drag sequence, a Fitts' Law model that used the vertical size of the text object as the target size gave the best fit. Dragging times were fitted well by Fitts' Law models that used either the vertical or horizontal size of the terminal character in the text object. Additional results of note were that pointing in the point-click sequence was consistently faster than in the point-drag sequence, and that pointing in either sequence was consistently faster than dragging. The discussion centres around the need to define task characteristics before applying Fitts' Law to an interface design or analysis, analyses of pointing and of dragging, and implications for interface design.