Christopher Flatley

Relation of reduced preclinical left ventricular diastolic function and cardiac remodeling in overweight youth to insulin resistance and inflammation

Insulin resistance (IR) and inflammation are associated with an increased risk of cardiovascular disease and may contribute to obesity cardiomyopathy. The earliest sign of obesity cardiomyopathy is impaired left ventricular (LV) diastolic function, which may be evident in obese children and adolescents. However, the precise metabolic basis of the impaired LV diastolic function remains unknown. The aims of this study were to evaluate cardiac structure and LV diastolic function by tissue Doppler imaging in overweight and obese (OW) youth and to assess the relative individual contributions of adiposity, IR, and inflammation to alterations in cardiac structure and function. We studied 35 OW (body mass index standard deviation score 2.0±0.8; non-IR n=19, IR n=16) and 34 non-OW youth (body mass index standard deviation score 0.1±0.7). LV diastolic function was reduced in OW youth compared with non-OW controls, as indicated by lower peak myocardial relaxation velocities (p<0.001) and greater filling pressures (p<0.001). OW youth also had greater LV mass index (p<0.001), left atrial volume index, and LV interventricular septal thickness (LV-IVS; both p=0.02). IR-OW youth had the highest LV filling pressures, LV-IVS, and relative wall thickness (all p<0.05). Homeostasis model of assessment-insulin resistance and C-reactive protein were negative determinants of peak myocardial relaxation velocity and positive predictors of filling pressure. Adiponectin was a negative determinant of LV-IVS, independent of obesity. In conclusion, OW youth with IR and inflammation are more likely to have adverse changes to cardiovascular structure and function which may predispose to premature cardiovascular disease in adulthood.

Perinatal risk factors for low and moderate five-minute Apgar scores at term

OBJECTIVE To evaluate the specific maternal and perinatal variables associated with a low (≤3) or moderate (4-6) Apgar score, compared to a high (≥7) score. STUDY DESIGN This was a retrospective, cohort study of 58429 term singleton babies born at the Mater Mothers Hospital in Brisbane, Australia in 2007-2013. Maternal demographics, socio-economic status using the Australian Socioeconomic Index for Areas (SEIFA) score, obstetric factors, and birth outcomes were compared for neonates grouped into three categories based on their five-minute Apgar: low (≤3), moderate (4-6) and high (≥7). The low- and moderate-score cohorts were individually compared to the high-score cohort using both univariate and multivariate analysis. RESULTS Logistic regression analysis confirmed that of the variables analysed, only maternal public insurance status (OR 2.1, 95% CI 1.5-3.1), breech presentation (OR 2.4, 95% CI 1.1-4.6), other non-cephalic presentation (OR 9.5, 95% CI 2.2-25.4), intramuscular narcotic use (OR 2.3, 95% CI 1.5-3.5), and presence of meconium (OR 3.7, 95% CI 2.5-5.4) were significantly associated with low Apgar scores. Variables significantly associated with a moderate score were: SEIFA ≤50th centile (OR 1.6, 95% CI 1.2-2.0) and 61st to 70th centile (OR 1.31, 95% CI 0.9-1.8) categories, maternal public insurance status (OR 2.7, 95% CI 2.2-3.3), nulliparity (OR 2.0, 95% CI 1.7-2.5), emergency caesarean birth (OR 2.6, 95% CI 2.1-3.2), instrumental birth (OR 2.3, 95% CI 1.9-2.9), and presence of meconium (OR 2.6, 95% CI 2.1-3.2). CONCLUSIONS Factors associated with low and moderate Apgar scores vary in type and degree of influence. Distinctions in the perinatal background can help predict newborn compromise and accelerate delivery of care.

Intrapartum intervention rates and perinatal outcomes following successful external cephalic version.

Objective:To determine intrapartum and perinatal outcomes following successful external cephalic version for breech presentation at term.Study Design:This was a retrospective cohort study of outcomes following successful external cephalic version in 411 women at an Australian tertiary maternity unit between November 2008 and March 2015. The study cohort was compared with a control group of 1236 women with cephalic presentation who underwent spontaneous labor. Intrapartum intervention rates and adverse neonatal outcomes were compared between both groups.Results:The success rate of external cephalic version (ECV) was 66.4%. The spontaneous vaginal delivery rate in the study cohort was 59.4% (224/411) vs 72.8% (900/1236) in the control cohort (P<0.001). Intrapartum intervention rates (emergency cesarean section (CS) and instrumental delivery) were higher in the ECV group (38% vs 27.2%, P<0.001). Rates of emergency CS for non-reassuring fetal status (9.5%, 39/411 vs 4.4%, 54/1236, P⩽0.001) and failure to progress (13.4%, 55/411 vs 4.1%, 51/1236, P<0.001) were higher in the study cohort. Neonatal outcomes were worse in the study cohort—Apgar score <7 at 5 min (2.2%, 9/411 vs 0.6%, 8/1236, P<0.001) and abnormal cord gases (8.5%, 35/411 vs 0.2%, 3/1236, P<0.001). Rates for resuscitation at birth and admission to the neonatal intensive care unit were higher in the study cohort (6.1% vs 4.1% and 1.9% vs 1.1%, respectively) but these were not statistically significant.Conclusion:Labor following successful ECV is more likely to result in increased intrapartum intervention rates and poorer neonatal outcomes.

Intrapartum intervention rates and perinatal outcomes following induction of labour compared to expectant management at term from an Australian perinatal centre

Induction of labor (IOL) is a common obstetric intervention, yet its impact on intervention rates and perinatal outcomes is conflicting.

The relationship between the five minute Apgar score, mode of birth and neonatal outcomes

Abstract Objective: To investigate the relationship between the five-minute Apgar score categories (low, intermediate, and normal), mode of birth and neonatal outcomes. Methods: This was a retrospective cross sectional study of term singleton deliveries at Mater Mothers’ Hospital in Brisbane, Australia between January 2007 and December 2015. The five minute score was subdivided in to three categories – low (0–3), intermediate (4–6), and normal (≥7). These were correlated with adverse neonatal outcomes and mode of birth. The referent cohort was the normal Apgar group. Results: The study cohort consisted of 39,258 births with a recorded five minute Apgar score. Of these, 38,705 (98.6%) neonates had a normal (≥7) Apgar score, 439 (1.1%) had an intermediate score (4–6) and 114 (0.3%) had a low (0–3) score. Neonatal complications including respiratory distress, feeding problems, hypothermia, and seizures were all significantly associated with both low and intermediate Apgar scores. Emergency operative birth (caesarean and instrumental) conveyed a higher risk of low and intermediate scores and poorer neonatal outcomes. Conclusions: Low and intermediate five minute Apgar scores were strongly associated with mode of birth and poorer neonatal outcomes.

Term small-for-gestational-age infants from low-risk women are at significantly greater risk of adverse neonatal outcomes

BACKGROUND Small‐for‐gestational‐age infants (birthweight <0th centile) are at increased risk of perinatal complications but are frequently not identified antenatally, particularly in low‐risk women delivering at term (≥37 weeks gestation). This is compounded by the fact that late pregnancy ultrasound is not the norm in many jurisdictions for this cohort of women. We thus investigated the relationship between birthweight <10th centile and serious neonatal outcomes in low‐risk women at term. OBJECTIVE(S) We aimed to determine whether there is a difference of obstetric and perinatal outcomes for small‐for‐gestational‐age infants, subdivided into fifth to <10th centile and less than the fifth centile cohorts compared with an appropriate‐for‐gestational age (birthweight 10th–90th centile) group at term. STUDY DESIGN This was a retrospective analysis of data from the Mater Mother’s Hospital in Brisbane, Australia, for women who delivered between January 2000 and December 2015. Women with multiple pregnancy, diabetes mellitus, hypertension, preterm birth, major congenital anomalies, and large for gestational age infants (>90th centile for gestational age) were excluded. Small‐for‐gestational‐age infants were subdivided into 2 cohorts: infants with birthweights from the fifth to <10th centile and those less than the fifth centile. Serious composite neonatal morbidity was defined as any of the following: Apgar score ≤3 at 5 minutes, respiratory distress syndrome, acidosis, admission into the neonatal intensive care unit, stillbirth, or neonatal death. Univariate and multivariate analyses were performed using generalized estimating equations to compare obstetric and perinatal outcomes for small‐for‐gestational‐age infants compared with appropriate‐for‐gestational age controls. RESULTS The final study comprised 95,900 infants. Five percent were between the fifth and <10th centiles for birthweight and 4.3% were less than the fifth centile. The rate of serious composite neonatal morbidity was 11.1% in the control group, 13.7% in the fifth and <10th centile, and 22.6% in the less than the fifth centile cohorts, respectively. Even after controlling for confounders, both the fifth to <10th centiles and less than the fifth centile cohorts were at significantly increased risk of serious composite neonatal morbidity compared with controls (odds ratio, 1.25, 95% confidence interval, 1.15–1.37, and odds ratio, 2.20, 95% confidence interval, 2.03–2.39, respectively). Infants with birthweights <10th centile were more likely to have severe acidosis at birth, 5 minute Apgar score ≤3 and to be admitted to the neonatal intensive care unit. The serious composite neonatal morbidity was higher in infants less than the fifth centile compared with those in the fifth to <10th centile cohort (odds ratio, 1.71, 95% confidence interval, 1.52–1.92). The odds of perinatal death (stillbirth and neonatal death) were significantly higher in both small‐for‐gestational age groups than controls. After stratification for gestational age at birth, the composite outcome remained significantly higher in both small‐for‐gestational‐age cohorts and was highest in the less than the fifth centile group at 37+0 to 38+6 weeks (odds ratio, 3.32, 95% confidence interval, 2.87–3.85). The risk of perinatal death was highest for infants less than the fifth centile at 37+0 to 38+6 weeks (odds ratio, 5.50, 95% confidence interval, 2.33–12.98). CONCLUSION Small‐for‐gestational‐age infants from term, low‐risk pregnancies are at significantly increased risk of mortality and morbidity when compared with appropriate‐for‐gestational age infants. Although this risk is increased at all gestational ages in infants less than the fifth centile for birthweight, it is highest at early‐term gestation. Our findings highlight that early‐term birth does not necessarily improve outcomes and emphasize the importance of identifying this cohort of infants.

The fetal cerebroplacental ratio in pregnancies complicated by gestational diabetes mellitus

To assess the relationship between the cerebroplacental ratio (CPR) and intrapartum and perinatal outcomes in pregnancies complicated by gestational diabetes mellitus (GDM).

Maternal demographic factors associated with emergency caesarean section for non-reassuring foetal status

Abstract Objectives: This study aimed to determine maternal and obstetric factors associated with emergency caesarean section (CS) for non-reassuring foetal status (NRFS). Materials and methods: This was a retrospective analysis of term singleton births between January 2007 and December 2015 at the Mater Mother’s Hospital in Brisbane. The study group comprised all cases of emergency CS for NRFS, and the control cohort comprised all other births meeting the inclusion criteria but excluding those in the study cohort. Results: Over the study period, there were 74,177 births fulfilling the inclusion criteria. The overall rate of emergency CS for NRFS was 4.2% (3132/74,177). Multivariate analysis showed that being overweight and obese, Indian and “other” ethnicity, artificial reproductive techniques, smoking, induction of labour and gestation at 39–42 weeks were associated with an increased risk, whereas being underweight, female sex, hypertension and birth without labour conferred a lower risk. Conclusion: Many maternal and obstetric factors were associated with emergency CS for NRFS and influenced adverse perinatal outcomes. Recognition of these risk factors could help risk stratify women prior to labour.

Reference centiles for the middle cerebral artery and umbilical artery pulsatility index and cerebro-placental ratio from a low-risk population - a Generalised Additive Model for Location, Shape and Scale (GAMLSS) approach

Abstract Objective: The primary aim of this study was to create reference ranges for the fetal Middle Cerebral artery Pulsatility Index (MCA PI), Umbilical Artery Pulsatility Index (UA PI) and the Cerebro–Placental Ratio (CPR) in a clearly defined low-risk cohort using the Generalised Additive Model for Location, Shape and Scale (GAMLSS) method. Methods: Prospectively collected cross-sectional biometry and Doppler data from low-risk women attending the Mater Mother’s Hospital, Maternal and Fetal Medicine Department in Brisbane, Australia between January 2010 and April 2017 were used to derive gestation specific centiles for the MCA PI, UA PI and CPR. All ultrasound scans were performed between 18 + 0 and 41 + 6 weeks gestation with recorded data for the MCA PI and/or UA PI. The GAMLSS method was used for the calculation of gestational age-adjusted centiles. Distributions and additive terms were assessed and the final model was chosen on the basis of the Global Deviance, Akaike information criterion (AIC) and Schwartz bayesian criterion (SBC), along with the results of the model and residual diagnostics as well as visual assessment of the centiles themselves. Results: Over the study period 6013 women met the inclusion criteria. The MCA PI was recorded in 4473 fetuses, the UA PI in 6008 fetuses and the CPR was able to be calculated in 4464 cases. The centiles for the MCA PI used a fractional polynomial additive term and Box-Cox t (BCT) distribution. Centiles for the UA PI used a cubic spline additive term with BCT distribution and the CPR used a fractional polynomial additive term and a BCT distribution. Conclusion: We have created gestational centile reference ranges for the MCA PI, UA PI and CPR from a large low-risk cohort that supports their applicability and generalisability.

Comparison between public and private sectors of care and disparities in adverse neonatal outcomes following emergency intrapartum cesarean at term - A retrospective cohort study

Background Perinatal outcomes may be influenced by a variety of factors including maternal demographics and medical condition as well as socio-economic status. The evidence for disparities in health outcomes stratified by type of care (public or private) is lacking. The aim of this study was to investigate short term neonatal outcomes following category 1 and 2 emergency cesareans at term between publicly and privately funded women at a single major tertiary centre in Australia. Category 1—immediate threat to life (maternal or fetal); Category 2—maternal or fetal compromise that is not immediately life-threatening. Methods This was a retrospective, cross sectional study of 61355 term singleton babies born at the Mater Mother’s Hospital in Brisbane, Australia in 2007–2014. We collected data from the hospital’s maternity database and compared maternal demographics, indications for cesarean and neonatal outcomes for publicly and privately funded women. Results Over the study period there were 32477 public and 28878 private, term singleton births. Compared to the publicly funded cohort, privately insured women were older, had lower BMI, were of Caucasian ethnicity, Australian born, nulliparous, had shorter labors and had lower rates of hypertensive disorders and diabetes. The most common indications for category 1 and category 2 cesareans in combination were non-reassuring fetal status followed by failure to progress in labor and malpresentation. For both category 1 and 2 cesareans, neonatal outcomes (Apgar score <7 at 5 minutes, abnormal cord gases, Neonatal Critical Care Unit admission rates, rates of severe respiratory distress and jaundice) were significantly worse in the publicly funded compared to the privately insured cohort Multivariate analyses controlling for maternal age, ethnicity, country of birth, parity, hypertension, diabetes mellitus, gestational age at birth and length of labour confirmed that private insurance status was highly protective for the perinatal outcomes of Apgar score <7 at 5 minutes (aOR 0.26, 95% CI 0.13–0.55), admission to NCCU (OR 0.51, 95% CI 0.30–0.92) and respiratory distress (aOR 0.60, 95% CI 0.41–0.86). Conclusion Birth in the private health sector was inversely associated with adverse neonatal outcomes following category 1 and 2 cesareans.