Lisa N. Yelland

Antenatal lifestyle advice for women who are overweight or obese: LIMIT randomised trial

Objective To determine the effect of antenatal dietary and lifestyle interventions on health outcomes in overweight and obese pregnant women. Design Multicentre randomised trial. We utilised a central telephone randomisation server, with computer generated schedule, balanced variable blocks, and stratification for parity, body mass index (BMI) category, and hospital. Setting Three public maternity hospitals across South Australia. Participants 2212 women with a singleton pregnancy, between 10+0 and 20+0 weeks’ gestation, and BMI ≥25. Interventions 1108 women were randomised to a comprehensive dietary and lifestyle intervention delivered by research staff; 1104 were randomised to standard care and received pregnancy care according to local guidelines, which did not include such information. Main outcome measures Incidence of infants born large for gestational age (birth weight ≥90th centile for gestation and sex). Prespecified secondary outcomes included birth weight >4000 g, hypertension, pre-eclampsia, and gestational diabetes. Analyses used intention to treat principles. Results 2152 women and 2142 liveborn infants were included in the analyses. The risk of the infant being large for gestational age was not significantly different in the two groups (lifestyle advice 203/1075 (19%) v standard care 224/1067 (21%); adjusted relative risk 0.90, 95% confidence interval 0.77 to 1.07; P=0.24). Infants born to women after lifestyle advice were significantly less likely to have birth weight above 4000 g (lifestyle advice 164/1075 (15%) v standard care 201/1067 (19%); 0.82, 0.68 to 0.99; number needed to treat (NNT) 28, 15 to 263; P=0.04). There were no differences in maternal pregnancy and birth outcomes between the two treatment groups. Conclusions For women who were overweight or obese, the antenatal lifestyle advice used in this study did not reduce the risk delivering a baby weighing above the 90th centile for gestational age and sex or improve maternal pregnancy and birth outcomes. Trial registration Australian and New Zealand Clinical Trials Registry (ACTRN12607000161426).

Performance of the Modified Poisson Regression Approach for Estimating Relative Risks From Clustered Prospective Data

Modified Poisson regression, which combines a log Poisson regression model with robust variance estimation, is a useful alternative to log binomial regression for estimating relative risks. Previous studies have shown both analytically and by simulation that modified Poisson regression is appropriate for independent prospective data. This method is often applied to clustered prospective data, despite a lack of evidence to support its use in this setting. The purpose of this article is to evaluate the performance of the modified Poisson regression approach for estimating relative risks from clustered prospective data, by using generalized estimating equations to account for clustering. A simulation study is conducted to compare log binomial regression and modified Poisson regression for analyzing clustered data from intervention and observational studies. Both methods generally perform well in terms of bias, type I error, and coverage. Unlike log binomial regression, modified Poisson regression is not prone to convergence problems. The methods are contrasted by using example data sets from 2 large studies. The results presented in this article support the use of modified Poisson regression as an alternative to log binomial regression for analyzing clustered prospective data when clustering is taken into account by using generalized estimating equations.

The effects of antenatal dietary and lifestyle advice for women who are overweight or obese on maternal diet and physical activity: the LIMIT randomised trial

BackgroundOverweight and obesity is a significant health concern during pregnancy. Our aim was to investigate the effect of providing antenatal dietary and lifestyle advice to women who are overweight or obese on components of maternal diet and physical activity.MethodsWe conducted a randomised controlled trial, in which pregnant women with a body mass index ≥25 kg/m2, and singleton gestation between 10+0 to 20+0 weeks were recruited and randomised to Lifestyle Advice (involving a comprehensive dietary and lifestyle intervention over their pregnancy) or Standard Care. Within the intervention group, we conducted a nested randomised trial in which a subgroup of women were further randomised to receive access to supervised group walking sessions in addition to the standard information presented during the intervention contacts (the Walking group) or standard information only.The outcome measures were maternal dietary intake, (including food groups, macronutrient and micronutrient intake, diet quality (using the Healthy Eating Index; HEI), dietary glycaemic load, and glycaemic index) and maternal physical activity. Women completed the Harvard Semi-Structured Food Frequency Questionnaire, and the Short Questionnaire to Assess Health-enhancing Physical Activity (SQUASH), at trial entry, 28 and 36 weeks’ gestational age, and 4 months postpartum.Analyses were performed on an intention-to-treat basis, using linear mixed effects models with adjustment for the stratification variables.ResultsWomen randomised to Lifestyle Advice demonstrated a statistically significant increase in the number of servings of fruit and vegetables consumed per day, as well as increased consumption of fibre, and reduced percentage energy intake from saturated fats (P < 0.05 for all). Maternal HEI was significantly improved at both 28 (73.35 ± 6.62 versus 71.86 ± 7.01; adjusted difference in means 1.58; 95% CI 0.89 to 2.27; P < 0.0001) and 36 (72.95 ± 6.82 versus 71.17 ± 7.69; adjusted difference in means 1.77; 95% CI 1.01 to 2.53; P < 0.0001) weeks. There were no differences in dietary glycaemic index or glycaemic load. Women randomised to Lifestyle Advice also demonstrated greater total physical activity (adjusted difference in means 359.76 metabolic equivalent task units (MET) minutes/week; 95% CI 74.87 to 644.65; P = 0.01) compared with women receiving Standard Care. The supervised walking group was poorly utilised.ConclusionsFor women who are overweight or obese, antenatal lifestyle advice improves maternal diet and physical activity during pregnancy.Please see related articles: http://www.biomedcentral.com/1741-7015/12/163 and http://www.biomedcentral.com/1741-7015/12/201.Trial registrationAustralian and New Zealand Clinical Trials Registry (http://ACTRN12607000161426)

Fish-oil supplementation in pregnancy does not reduce the risk of gestational diabetes or preeclampsia

BACKGROUND There is uncertainty regarding the efficacy of increasing n-3 long-chain PUFA (LCPUFA) intake during pregnancy in reducing the risk of gestational diabetes mellitus (GDM) and preeclampsia. OBJECTIVES The objective was to determine whether n-3 LCPUFA supplementation in pregnancy reduces the incidence of GDM or preeclampsia. A secondary objective was to assess the effect of n-3 LCPUFA supplementation on perinatal complications. DESIGN This was a double-blind, multicenter randomized control trial-the DHA to Optimize Mother Infant Outcome (DOMInO) trial. Pregnant women (n = 2399) of <21 wk gestation were randomly assigned to receive DHA-enriched fish oil (800 mg/d) or vegetable oil capsules without DHA from trial entry to birth. The presence of GDM or preeclampsia was assessed through a blinded audit of medical records. Birth outcomes and prenatal complications were also assessed. RESULTS The overall incidences of GDM and preeclampsia were 8% and 5%, respectively, based on clinical diagnosis. The RR of GDM was 0.97 (95% CI: 0.74, 1.27) and of preeclampsia was 0.87 (95% CI: 0.60, 1.25), and they did not differ significantly between the groups. Birth weight, length, and head circumference z scores also did not differ between the groups. There were 12 perinatal deaths and 5 neonatal convulsions in the control group compared with 3 perinatal deaths and no neonatal convulsions in the DHA group (P = 0.03 in both cases). CONCLUSION DHA supplementation of 800 mg/d in the second half of pregnancy does not reduce the risk of GDM or preeclampsia. Whether supplementation reduces the risk of perinatal death and neonatal convulsions requires further investigation. The DOMInO trial was registered with the Australian New Zealand Clinical Trials Registry as TRN12605000569606.

Patient satisfaction with point-of-care testing in general practice.

BACKGROUND Point-of-care testing is increasingly being used in general practice to assist GPs in their management of patients with chronic disease. However, patient satisfaction and acceptability of point-of-care testing in general practice has not been widely studied. AIM To determine if patients are more satisfied with point-of-care testing than with pathology laboratory testing for three chronic conditions. DESIGN OF STUDY As part of a large multicentre, randomised, controlled trial assessing the use of point-of-care testing in Australian general practice, satisfaction was measured for patients having pathology testing performed by point-of-care testing devices or pathology laboratories. Patients in the trial were managed by GPs for diabetes, hyperlipidaemia, and/or anticoagulant therapy. METHOD Patient satisfaction was measured using level of agreement with a variety of statements at the end of the study with a patient satisfaction questionnaire for both the intervention and control groups. Analysis was performed using a mixed model analysis of variance (ANOVA) with allowance for clustering at the practice level following Box-Cox transformations of the data to achieve normality. RESULTS Overall, intervention patients reported that they were satisfied with point-of-care testing. In comparison with the control group, the intervention group had a higher level of agreement than control patients with statements relating to their satisfaction with the collection process (P<0.001) and confidence in the process (P<0.001). They also viewed point-of-care testing as strengthening their relationship with their GP (P = 0.010) and motivational in terms of better managing their condition (P<0.001). CONCLUSION The results from this trial support patient satisfaction and acceptability of point-of-care testing in a general practice setting.

The effects of antenatal dietary and lifestyle advice for women who are overweight or obese on neonatal health outcomes: the LIMIT randomised trial

BackgroundOverweight and obesity during pregnancy represents a considerable health burden. While research has focused on interventions to limit gestational weight gain, there is little information describing their impact on neonatal health. Our aim was to investigate the effect on a range of pre-specified secondary neonatal outcomes of providing antenatal dietary and lifestyle advice to women who are overweight or obese.MethodsWe report a range of pre-specified secondary neonatal outcomes from a large randomised trial in which antenatal dietary and lifestyle advice was provided to women who were overweight or obese. Pregnant women were eligible for participation with a body mass index of 25 kg/m2 or over, and singleton gestation between 10+0 and 20+0 weeks. Outcome measures included gestational age at birth; Apgar score below 7 at 5 minutes of age; need for resuscitation at birth; birth weight above 4.5 kg or below 2.5 kg; birth weight, length and head circumference (and Z-scores); admission to the nursery; respiratory distress syndrome; and postnatal length of stay. Data relating to the primary outcome (large for gestational age infants defined as birth weight above the 90th centile) and birth weight above 4 kg have been reported previously. Analyses used intention-to-treat principles.ResultsIn total, 2,142 infants were included in the analyses. Infants born to women following lifestyle advice were significantly less likely to have birth weight above 4.5 kg (2.15% versus 3.69%; adjusted risk ratio (aRR) = 0.59; 95% confidence interval (CI) 0.36 to 0.98; P = 0.04), or respiratory distress syndrome (1.22% versus 2.57%; aRR = 0.47; 95% CI 0.24 to 0.90; P = 0.02), particularly moderate or severe disease, and had a shorter length of postnatal hospital stay (3.94 ± 7.26 days versus 4.41 ± 9.87 days; adjusted ratio of means 0.89; 95% CI 0.82 to 0.97; P = 0.006) compared with infants born to women who received Standard Care.ConclusionsFor women who are overweight or obese, antenatal dietary and lifestyle advice has health benefits for infants, without an increase in the risk of harm. Continued follow-up into childhood will be important to assess the longer-term effects of a reduction in high infant birth weight on risk of child obesity.Please see related articles: http://www.biomedcentral.com/1741-7015/12/161 and http://www.biomedcentral.com/1741-7015/12/201.Clinical trial registrationAustralian and New Zealand Clinical Trials Registry (http://ACTRN12607000161426)

A pragmatic cluster randomised controlled trial to evaluate the safety, clinical effectiveness, cost effectiveness and satisfaction with point of care testing in a general practice setting – rationale, design and baseline characteristics.

BackgroundPoint of care testing (PoCT) may be a useful adjunct in the management of chronic conditions in general practice (GP). The provision of pathology test results at the time of the consultation could lead to enhanced clinical management, better health outcomes, greater convenience and satisfaction for patients and general practitioners (GPs), and savings in costs and time. It could also result in inappropriate testing, increased consultations and poor health outcomes resulting from inaccurate results. Currently there are very few randomised controlled trials (RCTs) in GP that have investigated these aspects of PoCT.Design/MethodsThe Point of Care Testing in General Practice Trial (PoCT Trial) was an Australian Government funded multi-centre, cluster randomised controlled trial to determine the safety, clinical effectiveness, cost effectiveness and satisfaction of PoCT in a GP setting.The PoCT Trial covered an 18 month period with the intervention consisting of the use of PoCT for seven tests used in the management of patients with diabetes, hyperlipidaemia and patients on anticoagulant therapy. The primary outcome measure was the proportion of patients within target range, a measure of therapeutic control. In addition, the PoCT Trial investigated the safety of PoCT, impact of PoCT on patient compliance to medication, stakeholder satisfaction, cost effectiveness of PoCT versus laboratory testing, and influence of geographic location.DiscussionThe paper provides an overview of the Trial Design, the rationale for the research methodology chosen and how the Trial was implemented in a GP environment. The evaluation protocol and data collection processes took into account the large number of patients, the broad range of practice types distributed over a large geographic area, and the inclusion of pathology test results from multiple pathology laboratories.The evaluation protocol developed reflects the complexity of the Trial setting, the Trial Design and the approach taken within the funding provided. The PoCT Trial is regarded as a pragmatic RCT, evaluating the effectiveness of implementing PoCT in GP and every effort was made to ensure that, in these circumstances, internal and external validity was maintained.Trial Registration12612605000272695

Seven-year follow-up of children born to women in a randomized trial of prenatal DHA supplementation

The sale of prenatal supplements with docosahexaenoic acid (DHA) continues to increase, despite little evidence of benefit to offspring neurodevelopment.1 We randomized pregnant women to receive 800 mg of DHA daily or a placebo during the last half of pregnancy and found no group differences in cognitive, language, and motor development at 18 months of age, although secondary analyses revealed less cognitive delay but lower language scores in the DHA group.2 At 4 years of age there was no benefit of DHA supplementation in general intelligence, language, and executive functioning, and a possible negative effect on parent-rated behavior and executive functioning.3 This follow-up was designed to evaluate the effect of prenatal DHA on intelligence quotient (IQ) at 7 years, the earliest age at which adult performance can be indicated.

Correlations between blood and tissue omega-3 LCPUFA status following dietary ALA intervention in rats.

The aim of this study was to assess relationships between the fatty acid contents of plasma and erythrocyte phospholipids and those in liver, heart, brain, kidney and quadriceps muscle in rats. To obtain a wide range of tissue omega-3 (n-3) long chain polyunsaturated fatty acids (LCPUFA) we subjected weanling rats to dietary treatment with the n-3 LCPUFA precursor, alpha linolenic acid (ALA, 18:3 n-3) for 3 weeks. With the exception of the brain, we found strong and consistent correlations between the total n-3 LCPUFA fatty acid content of both plasma and erythrocyte phospholipids with fatty acid levels in all tissues. The relationships between eicosapentaenoic acid (EPA, 20:5 n-3) and docosapentaenoic acid (DPA, 22:5 n-3) content in both blood fractions with levels in liver, kidney, heart and quadriceps muscle phospholipids were stronger than those for docosahexaenoic acid (DHA, 22:6 n-3). The strong correlations between the EPA+DHA (the Omega-3 Index), total n-3 LCPUFA and total n-3 PUFA contents in both plasma and erythrocyte phospholipids and tissues investigated in this study suggest that, under a wide range of n-3 LCPUFA values, plasma and erythrocyte n-3 fatty acid content reflect not only dietary PUFA intakes but also accumulation of endogenously synthesised n-3 LCPUFA, and thus can be used as a reliable surrogate for assessing n-3 status in key peripheral tissues.

Does maternal depression predict developmental outcome in 18 month old infants

AIM Our aim was to examine the associations between maternal depression in the first 6 months postpartum, home environment and cognitive, language and motor development in infants at 18 months of age. STUDY DESIGN AND METHODS This article reports results from the control group (n=312 full term; n=48 preterm) of the prospective Docosahexaenoic acid (DHA) to Optimise Maternal Infant Outcome (DOMInO) Randomised Controlled Trial. Mothers in South Australia completed the Edinburgh Postnatal Depression Scale (EPDS) at 6 weeks and 6 months postpartum. Infant development was assessed when children were 18 months old with the Bayley Scales of Infant and Toddler Development Version III and mothers completed the Home Screening Questionnaire at this assessment. RESULTS There were no significant associations between maternal depression in the first 6 months postpartum and cognitive, language or motor development after controlling for infant prematurity, breastfeeding status and socio-economic level. Home environment remained a significant predictor of development after controlling for potential confounding variables. Using mediation models, we did not find an association between maternal depression and developmental outcome through home environment. CONCLUSIONS Maternal depression in the first 6 months postpartum was not associated with infant development at 18 months of age. Further studies should focus on women with chronic depression.