Camille Raynes-Greenow

Quality of data in perinatal population health databases: a systematic review.

BackgroundAdministrative or population health datasets (PHDS) are increasingly being used for research related to maternal and infant health. However, the accuracy and completeness of the information in the PHDS is important to ensure validity of the results of this research. ObjectiveTo compile and review studies that validate the reporting of conditions and procedures related to pregnancy, childbirth, and newborns and provide a tool of reference for researchers. MethodsA systematic search was conducted of Medline and EMBASE databases to find studies that validated routinely collected datasets containing diagnoses and procedures related to pregnancy, childbirth, and newborns. To be included datasets had to be validated against a gold standard, such as review of medical records, maternal interview or survey, specialized register, or laboratory data. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and/or &kgr; statistic for each diagnosis or procedure code were calculated. ResultsForty-three validation studies were included. Under-enumeration was common, with the level of ascertainment increasing as time from diagnosis/procedure to birth decreased. Most conditions and procedures had high specificities indicating few false positives, and procedures were more accurately reported than diagnoses. Hospital discharge data were generally more accurate than birth data, however identifying cases from more than 1 dataset further increased ascertainment. ConclusionsThis comprehensive collection of validation studies summarizing the quality of perinatal population data will be an invaluable resource to all researchers working with PHDS.

Is there an association between endometriosis and the risk of pre-eclampsia? A population based study

BACKGROUND An association between endometriosis and reduced risk of pre-eclampsia has recently been reported. Longitudinally-linked electronic hospital records are a valuable resource for investigating such findings in a large, population-based sample. Our aim was to determine whether women with a history of endometriosis were at modified risk for pregnancy hypertension or pre-eclampsia. METHODS A population-based, longitudinal study of all women in the Australian state of New South Wales, aged from 15 to 45 years of age with a singleton birth during the period 2000-2005. Endometriosis was identified using ICD-10 codes. Endometriosis subgroups were analysed based on: (i) site of endometriosis (ovary or peritoneum), (ii) multiple (i.e. two or more) sites affected and (iii) infertility. To investigate the association between pregnancy hypertension and endometriosis, number of weeks gestation at birth and maternal age, we used logistic regression. RESULTS In the 3239 (1.6%) women with endometriosis diagnosed before their first birth, 352 (10.9%) had a diagnosis of pregnancy hypertension compared with 23,186/205,640 (11.3%) in women with no endometriosis diagnosis (OR 0.96; 95% CI 0.9-1.3). The frequency of pregnancy hypertension and pre-eclampsia was not significantly different in women with more severe endometriosis or endometriosis in conjunction with infertility when compared with those with no endometriosis. After adjusting for maternal age and weeks gestation there was still no altered risk. CONCLUSIONS We have found no evidence for an association between endometriosis and subsequent risk of either pregnancy hypertension or pre-eclampsia in this large population-based dataset.

Evaluation of a decision aid for women with breech presentation at term: a randomised controlled trial [ISRCTN14570598]

Objectives  To evaluate the effectiveness of a decision aid for women with a breech presentation compared with usual care.

Sleep position, fetal growth restriction, and late-pregnancy stillbirth: the Sydney stillbirth study.

OBJECTIVE: To identify potentially modifiable risk factors for late-pregnancy stillbirth. METHODS: This was a population-based matched case–control study of pregnant women at 32 weeks of gestation or greater booked into tertiary maternity hospitals in metropolitan Sydney between January 2006 and December 2011. The case group consisted of women with singleton pregnancies with antepartum fetal death in utero. Women in the control group were matched for booking hospital and expected delivery date with women in the case group. Data collection was performed using a semistructured interview and included validated questionnaires for specific risk factors. Adjusted odds ratios (ORs) were calculated for a priori-specified risk factors using conditional logistic regression. RESULTS: There were 103 women in the case group and 192 women in the control group. Mean gestation was 36 weeks. Supine sleeping was reported by 10 of 103 (9.7%) of women who experienced late-pregnancy stillbirth and by 4 of 192 (2.1%) of women in the control group (adjusted OR 6.26, 95% confidence interval [CI] 1.2–34). Women who experienced stillbirth were more likely to: have been followed during pregnancy for suspected fetal growth restriction, 11.7% compared with 1.6% (adjusted OR 5.5, 95% CI 1.36–22.5); not be in paid work, 25.2% compared with 9.4% (adjusted OR 2.9, 95% CI 1.1–7.6); and to have not received further education beyond high school, 41.7% compared with 25.5% (adjusted OR 1.9, 95% CI 1.1–3.5). None of the deaths to women who reported supine sleeping were classified as unexplained. CONCLUSION: This study suggests that supine sleep position may be an additional risk for late-pregnancy stillbirth in an already compromised fetus. The clinical management of suspected fetal growth restriction should be investigated further as a means of reducing late stillbirth. LEVEL OF EVIDENCE: II

Sleep Apnea in Early Childhood Associated with Preterm Birth but Not Small for Gestational Age: A Population-Based Record Linkage Study

STUDY OBJECTIVES Investigate the relationship between gestational age and weight for gestational age and sleep apnea diagnosis in a cohort of children aged up to 6 years old. DESIGN A cohort study, using record linked population health data. SETTING New South Wales, Australia. PARTICIPANTS 398,961 children, born between 2000 and 2004, aged 2.5 to 6 years. MEASUREMENTS The primary outcome was sleep apnea diagnosis in childhood, first diagnosed between 1 and 6 years of age. Children with sleep apnea were identified from hospital records with the ICD-10 code G47.3: sleep apnea, central or obstructive. RESULTS A total of 4,145 (1.0%) children with a first diagnosis of sleep apnea were identified. Mean age at first diagnosis was 44.2 months (SD 13.9). Adenoidectomy, tonsillectomy, or both were common among the children diagnosed with sleep apnea (85.6%). Children born preterm compared to term were significantly more likely to be diagnosed with sleep apnea (< 32 weeks versus term hazard ratio 2.74 [95% CI: 2.16, 3.49]) this remained even after adjustment for known confounding variables. Children born small for gestational age were not at increased risk of sleep apnea compared to children born appropriate for gestational age, hazard ratio 0.95 (95% CI 0.86-1.06). CONCLUSIONS This is the largest study investigating preterm birth and sleep apnea diagnosis and suggests that diagnosis of sleep disordered breathing is more prevalent in children born preterm, but not those who are small for gestational age.

Neonatal length inaccuracies in clinical practice and related percentile discrepancies detected by a simple length-board.

The study aims to assess accuracy of standard practice measurement of neonatal length compared with a gold‐standard length‐board technique.

Assisting informed decision making for labour analgesia: a randomised controlled trial of a decision aid for labour analgesia versus a pamphlet

BackgroundMost women use some method of pain relief during labour. There is extensive research evidence available of pharmacological pain relief during labour; however this evidence is not readily available to pregnant women. Decision aids are tools that present evidence based information and allow preference elicitation.MethodsWe developed a labour analgesia decision aid. Using a RCT design women either received a decision aid or a pamphlet. Eligible women were primiparous, ≥ 37 weeks, planning a vaginal birth of a single infant and had sufficient English to complete the trial materials. We used a combination of affective (anxiety, satisfaction and participation in decision-making) and behavioural outcomes (intention and analgesia use) to assess the impact of the decision aid, which were assessed before labour.Results596 women were randomised (395 decision aid group, 201 pamphlet group). There were significant differences in knowledge scores between the decision aid group and the pamphlet group (mean difference 8.6, 95% CI 3.70, 13.40). There were no differences between decisional conflict scores (mean difference -0.99 (95% CI -3.07, 1.07), or anxiety (mean difference 0.3, 95% CI -2.15, 1.50). The decision aid group were significantly more likely to consider their care providers opinion (RR 1.28 95%CI 0.64, 0.95). There were no differences in analgesia use and poor follow through between antenatal analgesia intentions and use.ConclusionsThis decision aid improves womens labour analgesia knowledge without increasing anxiety. Significantly, the decision aid group were more informed of labour analgesia options, and considered the opinion of their care providers more often when making their analgesia decisions, thus improving informed decision making.Trial RegistrationTrial registration no: ISRCTN52287533

Population-Based Surveillance of Neonatal Herpes Simplex Virus Infection in Australia, 1997–2011

BACKGROUND Neonatal herpes simplex virus (HSV) infection is uncommon, but mortality after disseminated disease and morbidity after encephalitis are high. For the last decade, increased dose and duration of acyclovir has been advised to prevent disease progression and recurrence. We sought to determine prospectively the epidemiologic, clinical, and secular trends of this condition in Australia. METHODS This was prospective national active surveillance for neonatal HSV disease through the Australian Paediatric Surveillance Unit from 1997 to 2011. Case notification triggered a questionnaire requesting de-identified data from the pediatric clinician. RESULTS We identified 131 confirmed cases of neonatal HSV disease in 15 years from 261 notifications (95% response). The reported incidence (3.27 cases per 100 000 live births overall; 95% confidence interval [CI], 2.73-3.86) was stable. Overall mortality was 18.8% (95% CI, 12.1-25.5); the mortality rate was significantly lower in the latter part of the study period, 2005-2011, compared with 1997-2004 (P = .04). There were significantly more young mothers (<20 years of age) compared with Australian birth record data (18.5% vs 4.8%; P < .001). HSV-1 infection was more common than HSV-2 (62.7% vs 37.3%; P < .001), and the rate of HSV-1 infections increased significantly over the surveillance period (P < .05). From 2002, most infants received high-dose acyclovir. The time from symptom onset to initiation of therapy in survivors did not change over time. CONCLUSIONS Mortality from neonatal HSV infection has fallen but remains high. HSV-1 is the major serotype causing neonatal disease in Australia. Young mothers represent an important target group for prevention.

Effect of Long-Term Infection with nef-Defective Attenuated HIV Type 1 on CD4+ and CD8+ T Lymphocytes: Increased CD45RO+ CD4+ T Lymphocytes and Limited Activation of CD8+ T Lymphocytes

Members of the Sydney Blood Bank Cohort (SBBC) have been infected with an attenuated strain of HIV-1 with a natural nef/LTR mutation and have maintained relatively stable CD4+ T lymphocyte counts for 14-18 years. Flow cytometric analysis was used to examine the phenotype of CD4+ and CD8+ T lymphocytes in these subjects, including the immunologically important naive (CD45RA+CD62L+), primed (CD45RO+), and activated (CD38+HLA-DR+ and CD28-) subsets. The median values were compared between the SBBC and control groups, comprising age-, sex-, and transfusion-matched HIV-1-uninfected subjects; transfusion-acquired HIV-1-positive LTNPs; and sexually acquired HIV-1-positive LTNPs. Members of the SBBC not only had normal levels of naive CD4+ and CD8+ T lymphocytes, but had primed CD45RO+ CD4+ T lymphocytes at or above normal levels. Furthermore, these primed cells expressed markers suggesting recent exposure to specific antigen. SBBC members exhibited variable activation of CD8+ T lymphocytes. In particular, SBBC members with undetectable plasma HIV-1 RNA had normal levels of activated CD8+ T lymphocytes. Therefore, the result of long-term infection with natural nef/LTR mutant HIV-1 in these subjects suggests a decreased cytopathic effect of attenuated HIV-1 on susceptible activated CD4+ T lymphocyte subsets in vivo, and minimal activation of CD8+ T lymphocytes.

Risk factors for antepartum stillbirth and the influence of maternal age in New South Wales Australia: A population based study

BackgroundMaternal age is a known risk factor for stillbirth and delayed childbearing is a societal norm in developed country settings. The timing and reasons for age being a risk factor are less clear. This study aimed to document the gestational specific risk of maternal age throughout pregnancy and whether the underlying causes of stillbirth differ for older women.MethodsUsing linkage of state maternity and perinatal death data collections the authors assessed risk factors for antepartum stillbirth in New South Wales Australia for births between 2002 – 2006 (n = 327,690) using a Cox proportional hazards model. Gestational age specific risk was calculated for different maternal age groups. Deaths were classified according to the Perinatal Mortality Classifications of the Perinatal Society of Australia and New Zealand.ResultsMaternal age was a significant independent risk factor for antepartum stillbirth (35 – 39 years HR 1.4 95% CI 1.12 – 1.75; ≥ 40 years HR 2.41 95% CI 1.8 – 3.23). Other significant risk factors were smoking HR 1.82 (95% CI 1.56 –2.12) nulliparity HR 1.23 (95% CI 1.08 – 1.40), pre-existing hypertension HR 2.77 (95% CI 1.94 – 3.97) and pre-existing diabetes HR 2.65 (95% CI 1.63 – 4.32). For women aged 40 or over the risk of antepartum stillbirth beyond 40 weeks was 1 in 455 ongoing pregnancies compared with 1 in 1177 ongoing pregnancies for those under 40. This risk was increased in nulliparous women to 1 in 247 ongoing pregnancies. Unexplained stillbirths were the most common classification for all women, stillbirths classified as perinatal infection were more common in the women aged 40 or above.ConclusionsWomen aged 35 or older in a first pregnancy should be counselled regarding stillbirth risk at the end of pregnancy to assist with informed decision making regarding delivery. For women aged 40 or older in their first pregnancy it would be reasonable to offer induction of labour by 40 weeks gestation.