Dietary interventions in overweight and obese pregnant women: a systematic review of the content, delivery, and outcomes of randomized controlled trials

CONTEXT

Interventions targeting maternal obesity are a healthcare and public health priority.

OBJECTIVE

The objective of this review was to evaluate the adequacy and effectiveness of the methodological designs implemented in dietary intervention trials for obesity in pregnancy.

DATA SOURCES

A systematic review of the literature, consistent with PRISMA guidelines, was performed as part of the International Weight Management in Pregnancy collaboration.

STUDY SELECTION

Thirteen randomized controlled trials, which aimed to modify diet and physical activity in overweight and obese pregnant women, were identified.

DATA SYNTHESIS

There was significant variability in the content, delivery, and dietary assessment methods of the dietary interventions examined. A number of studies demonstrated improved dietary behavior in response to diet and/or lifestyle interventions. Nine studies reduced gestational weight gain.

CONCLUSION

This review reveals large methodological variability in dietary interventions to control gestational weight gain and improve clinical outcomes in overweight and obese pregnant women. This lack of consensus limits the ability to develop clinical guidelines and apply the evidence in clinical practice.

Expression of myogenic regulatory factors during the development of mouse tongue striated muscle

While the role of myogenic regulatory factors (MRFs) in skeletal myogenesis has been well evaluated in limb and trunk muscles, very little is known about their role in tongue myogenesis. Here the expression of MRF mRNA in mouse tongue muscle was examined during development from embryonic day (E)11 to birth and compared them with that in hind-limb muscle. Desmin, muscle creatine kinase and troponin C mRNAs were used as markers for myoblast determination, myotubule formation and myofibre maturation, respectively. The mRNA quantities were determined by competitive reverse transcriptase-polymerase chain reaction. The expression profile of desmin mRNA indicated that myoblast determination occurred before E11 in both the tongue and hind-limb muscles; the profile of muscle creatine kinase and troponin C mRNAs indicated that myotubule formation and myofibre maturation began between E11 and 13 in both tongue and hind-limb muscles, but ended 2 days earlier in the tongue than in the hind limb. Expression of myoD and myogenin mRNAs began at E11, increased, and showed peak values earlier in the tongue muscle (E13) than in the hind-limb muscle (E15). Expression of MRF4 mRNA appeared earlier in the tongue (E13) than in the hind-limb muscle (E15) and increased in both muscles after that. These results suggest that myotubule formation and myofibre maturation in the tongue muscle progress faster than in the hind-limb muscle, a result of earlier expression of myoD, myogenin, and MRF4 in response to earlier functional demands such as suckling immediately after birth.

A simpler definition of major depressive disorder

BACKGROUND

The DSM-IV symptom criteria for major depressive disorder (MDD) are somewhat lengthy, with many studies showing that treatment providers have difficulty recalling all nine symptoms. Moreover, the criteria include somatic symptoms that are difficult to apply in patients with medical illnesses. In a previous report, we developed a briefer definition of MDD that was composed of the mood and cognitive symptoms of the DSM-IV criteria, and found high levels of agreement between the simplified and full DSM-IV definitions. The goal of the present study was to replicate these findings in another large sample of psychiatric out-patients and to extend the findings to other patient samples.

METHOD

We interviewed 1100 psychiatric out-patients and 210 pathological gamblers presenting for treatment and 1200 candidates for bariatric surgery. All patients were interviewed by a diagnostic rater who administered a semi-structured interview. We inquired about all symptoms of depression for all patients.

RESULTS

In all three samples high levels of agreement were found between the DSM-IV and the simpler definition of MDD. Summing across all 2510 patients, the level of agreement between the two definitions was 95.5% and the kappa coefficient was 0.87.

CONCLUSIONS

After eliminating the four somatic criteria from the DSM-IV definition of MDD, a high level of concordance was found between this simpler definition and the original DSM-IV classification. This new definition offers two advantages over the current DSM-IV definition--it is briefer and it is easier to apply with medically ill patients because it is free of somatic symptoms.

The influence of homologous blood transfusion on immunity and clinical outcome in aortic surgery

OBJECTIVES

To evaluate the influence of homologous blood transfusion on immune responses and post-operative morbidity in aortic surgery.

DESIGN

Analysis of the effects of homologous blood transfusion in 128 patients in a prospective randomised trial evaluating homologous and autologous blood transfusion in aortic surgery.

MATERIALS AND METHODS

Blood sampled before and at five times after surgery was assayed for C-reactive protein (CRP), neutrophil elastase, TNF-alpha and IL-6. Transfusions, morbidity and mortality were recorded; factors associated with poor outcome were identified by logistic regression.

RESULTS

homologous transfusion during surgery was required in 32 patients and precipitated an increase in neutrophil elastase (p=0.008) and TNF-alpha (p=0.015) but not IL-6 and CRP. Elastase peaked early in transfused patients at 41.27 (13.92-52.11) Deltang/ml by 2 h compared to a peak of 21.51 (10.64-31.13) Deltang/ml by 24 h in those who were not transfused. TNF-alpha peaked at 1.2 (0-4.33) Deltapg/ml by wound closure in transfused patients and at -0.1 (-2.05-2.52) Deltapg/ml by 2 h without transfusion. Intra-operative homologous transfusion was associated with increased mortality (p=0.01) and prolonged intensive care stay (p=0.03). Mortality increased with age (p=0.003) and was inversely related to the CRP peak (p=0.007). Prolonged surgery predicted post-operative complications (p=0.025).

CONCLUSION

Homologous transfusion increased the inflammatory response to aortic surgery and was associated with mortality.

Relationships between Maternal Obesity and Maternal and Neonatal Iron Status

Obesity in pregnancy may negatively influence maternal and infant iron status. The aim of this study was to examine the association of obesity with inflammatory and iron status in both mother and infant in two prospective studies in pregnancy: UPBEAT and SCOPE. Maternal blood samples from obese (n = 245, BMI ≥ 30 kg/m²) and normal weight (n = 245, BMI < 25 kg/m²) age matched pregnant women collected at approximately 15 weeks’ gestation, and umbilical cord blood samples collected at delivery, were analysed for a range of inflammatory and iron status biomarkers. Concentrations of C- reactive protein and Interleukin-6 in obese women compared to normal weight women were indicative of an inflammatory response. Soluble transferrin receptor (sTfR) concentration [18.37 nmol/L (SD 5.65) vs. 13.15 nmol/L (SD 2.33)] and the ratio of sTfR and serum ferritin [1.03 (SD 0.56) vs. 0.69 (SD 0.23)] were significantly higher in obese women compared to normal weight women (P < 0.001). Women from ethnic minority groups (n = 64) had higher sTfR concentration compared with white women. There was no difference in maternal hepcidin between obese and normal weight women. Iron status determined by cord ferritin was not statistically different in neonates born to obese women compared with neonates born to normal weight women when adjusted for potential confounding variables. Obesity is negatively associated with markers of maternal iron status, with ethnic minority women having poorer iron statuses than white women.

Direct DNA injection into mouse tongue muscle for analysis of promoter function in vivo

The striated muscle of the tongue provides a readily accessible site for the introduction of DNA expression vectors. Parameters were established to use the striated muscle of the tongue as a model system for the examination of gene expression following the direct injection of DNA constructs bearing gene promoter sequences controlling the expression of reporter genes. Plasmid expression vectors were used that contained either constitutive or muscle-specific promoters directing the transcription of reporter genes. Chloramphenicol acetyltransferase (CAT), luciferase, and beta-galactosidase (lacZ) were used as the reporter genes to detect the promoter-specific expression of the injected DNA. The expression of the injected plasmids was directly correlated with the mass of injected DNA and the time of incubation following the injection. Maximal levels of reporter gene expression were observed seven days after the injection, and the expression was maintained for more than two months following injection. Simultaneous injection of two individual expression vectors bearing either CAT or luciferase reporter genes resulted in a dose-dependent level of expression for each of the plasmids. The linearity of the coexpression provided a means to normalize DNA uptake and analyze promoter efficiency. The troponin C-fast enhancer linked to its own promoter directed significantly more CAT expression than an enhancerless SV40 promoter-CAT plasmid, demonstrating that different promoter strengths could be determined in the mouse tongue muscle in vivo. This model system represents a convenient means to approach the functional analysis of muscle gene promoters in vivo.

Economic evaluation of a randomized clinical trial of haemodilution with cell salvage in aortic surgery

BACKGROUND

This study evaluated the costs of acute normovolaemic haemodilution (ANH) and intraoperative cell salvage (ICS) versus homologous blood transfusion in aortic surgery in a prospective multicentre randomized trial.

METHODS

One hundred and forty-five patients were randomized either to standard transfusion practice (homologous) or to a combination of ANH and ICS (autologous). Costs for each inpatient admission were identified. Cell salvage costs were assigned on the assumption that 50 operations were done each year employing a trained cell salvage operator. The results were analysed statistically using bias-corrected bootstrap analysis.

RESULTS

Patients who had transfusion of homologous blood received some 251 units and those having a homologous transfusion received 103 units (P = 0.008). There was no difference in morbidity, mortality and duration of hospital stay. Transfusion-related mean costs were similar at 340 UK pounds for patients having a homologous transfusion and 357 UK pounds for those receiving autologous blood (mean difference 17 UK pounds (95 per cent confidence interval [c.i.]--184 UK pounds to 174 UK pounds); P not significant). There was also no significant difference in mean overall costs: 5859 UK pounds for homologous and 5384 UK pounds for autologous transfusion (mean difference--475 UK pounds (95 per cent c.i.--2231 UK pounds to 1342 UK pounds)). Sensitivity analysis showed that costs remained similar for 20 and 150 operations per annum. Exclusion of a dedicated cell salvage operator reduced autologous transfusion costs but did not have a significant impact on overall cost.

CONCLUSION

Autologous transfusion is cost neutral in aortic surgery even when surgical activity is low.

Project20: Does continuity of care and community-based antenatal care improve maternal and neonatal birth outcomes for women with social risk factors? A prospective, observational study

BACKGROUND

Social factors associated with poor childbirth outcomes and experiences of maternity care include minority ethnicity, poverty, young motherhood, homelessness, difficulty speaking or understanding English, migrant or refugee status, domestic violence, mental illness and substance abuse. It is not known what specific aspects of maternity care work to improve the maternal and neonatal outcomes for these under-served, complex populations.

METHODS

This study aimed to compare maternal and neonatal clinical birth outcomes for women with social risk factors accessing different models of maternity care. Quantitative data on pregnancy and birth outcome measures for 1000 women accessing standard care, group practice and specialist models of care at two large, inner-city maternity services were prospectively collected and analysed using multinominal regression. The level of continuity of care and place of antenatal care were used as independent variables to explore these potentially influential aspects of care. Outcomes adjusted for women's social and medical risk factors and the service attended.

RESULTS

Women who received standard maternity care were significantly less likely to use water for pain relief in labour (RR 0.11, CI 0.02-0.62) and have skin to skin contact with their baby shortly after birth (RR 0.34, CI 0.14-0.80) compared to the specialist model of care. Antenatal care based in the hospital setting was associated with a significant increase in preterm birth (RR 2.38, CI 1.32-4.27) and low birth weight (RR 2.31, CI 1.24-4.32), and a decrease in induction of labour (RR 0.65, CI 0.45-0.95) compared to community-based antenatal care, this was despite women's medical risk factors. A subgroup analysis found that preterm birth was increased further for women with the highest level of social risk accessing hospital-based antenatal care (RR 3.11, CI1.49-6.50), demonstrating the protective nature of community-based antenatal care.

CONCLUSIONS

This research highlights how community-based antenatal care, with a focus on continuity of carer reduced health inequalities and improved maternal and neonatal clinical outcomes for women with social risk factors. The findings support the current policy drive to increase continuity of midwife-led care, whilst adding that community-based care may further improve outcomes for women at increased risk of health inequalities. The relationship between community-based models of care and neonatal outcomes require further testing in future research. The identification of specific mechanisms such as help-seeking and reduced anxiety, to explain these findings are explored in a wider evaluation.

Differential expression of troponin C genes during tongue myogenesis

Determination of muscle fiber type is related to the developmental stage of the tissue. Ordinarily the final distribution of fast and slow fibers in a muscle is determined postnatally. Tongue muscle, however, is composed solely of fast-twitch fibers that express only troponin C fast mRNA and fast (type II) myosin heavy chain (MHC) proteins in both the adult and the one-day-old mouse. The fiber-type determination of this muscle was examined during fetal development. Both troponin C fast and slow mRNAs were expressed at initial stages of tongue development at embryonic day 18. However, by embryonic day 16 the troponin C fast transcripts predominated. AT 17 days of embryonic development, TnC fast mRNA was 10 times more abundant than TnC slow, and at 18 days of development the TnC slow mRNA was barely detectable. The tongue muscle myotubes expressed fast, slow, and embryonic MHC isoforms during early embryonic development. At 18 days of gestation, the MHC isoform expressed by the majority of the myotubes was the fast isoform, whereas the slow isoform was present in very few fibers. RT-PCR analysis of the MHC transcripts present throughout tongue development demonstrated expression of the mdms or type IIx MHC in both late fetal and postnatal stages of development. In contrast, the type I/beta slow MHC mRNA was undetectable in the postnatal and adult tongue. The absence of TnC and MHC slow-isoform mRNAs in the newborn mouse tongue suggests that slow isoform genes become dominantly repressed with the TnC-F and MHC type IIx genes remaining transcriptionally active, giving rise to an unusually homogeneous fast-twitch phenotype. The tongue muscle fibers acquire their specific adult-type fiber characteristics during fetal development rather than postnatally.

Vascular surgical society of great britain and ireland: autologous transfusion reduces blood transfusion requirements in aortic surgery

BACKGROUND: Elective aortic surgery is associated with a blood loss that warrants a routine blood crossmatch of 4-6 units. Autologous transfusion strategies to reduce blood requirements were evaluated in a pilot study involving six hospitals in the North West. METHODS: Eighty patients undergoing elective aortic surgery were randomized to either autologous (a combination of acute normovolaemic haemodilution and intraoperative cell salvage) or homologous transfusion. The transfusion trigger, in the absence of pressing clinical need, was 8 g dl-1 haemoglobin for both groups. RESULTS: Randomization achieved two groups well matched for age, aneurysm or occlusive surgery, aspirin intake, estimated blood volume, preoperative haemoglobin and aneurysm size. In the 'best' hospitals (n = 49) mean(s.d.) blood loss (630(49) ml) was significantly lower (P < 0.01) than that in the 'worst' hospitals (1077(110) ml, n = 31) and fewer patients required transfusion (nine of 42 versus 15 of 30; P < 0.05). No significant differences were found between homologous and autologous groups for all variables measured in the 'best' hospitals. In the 'worst' hospitals blood requirements were significantly higher (P < 0.05) for the homologous group (800(112) ml) compared with the autologous group (489(65) ml), although blood loss was similar (1239(195) versus 915(92) ml respectively). CONCLUSION: Autologous transfusion techniques significantly reduced homologous blood requirements in aortic surgery where blood loss exceeded 800 ml.

DNA methylation signatures in cord blood associated with birthweight are enriched for dmCpGs previously associated with maternal hypertension or pre-eclampsia, smoking and folic acid intake

Many epidemiological studies have linked low birthweight to an increased risk of non-communicable diseases (NCDs) in later life, with epigenetic proceseses suggested as an underlying mechanism. Here, we sought to identify neonatal methylation changes associated with birthweight, at the individual CpG and genomic regional level, and whether the birthweight-associated methylation signatures were associated with specific maternal factors. Using the Illumina Human Methylation EPIC array, we assessed DNA methylation in the cord blood of 557 and 483 infants from the UK Pregnancies Better Eating and Activity Trial and Southampton Women's Survey, respectively. Adjusting for gestational age and other covariates, an epigenome-wide association study identified 2911 (FDR≤0.05) and 236 (Bonferroni corrected p ≤ 6.45×10-8) differentially methylated CpGs (dmCpGs), and 1230 differentially methylated regions (DMRs) (Stouffer ≤0.05) associated with birthweight. The top birthweight-associated dmCpG was located within the Homeobox Telomere-Binding Protein 1 (HMBOX1) gene with a 195 g (95%CI: -241, -149 g) decrease in birthweight per 10% increase in methylation, while the top DMR was located within the promoter of corticotropin-releasing hormone-binding protein (CRHBP). Furthermore, the birthweight-related dmCpGs were enriched for dmCpGs previously associated with gestational hypertension/pre-eclampsia (14.51%, p = 1.37×10-255), maternal smoking (7.71%, p = 1.50 x 10-57) and maternal plasma folate levels during pregnancy (0.33%, p = 0.029). The identification of birthweight-associated methylation markers, particularly those connected to specific pregnancy complications and exposures, may provide insights into the developmental pathways that affect birthweight and suggest surrogate markers to identify adverse prenatal exposures for stratifying for individuals at risk of later NCDs.

Project20: maternity care mechanisms that improve access and engagement for women with social risk factors in the UK - a mixed-methods, realist evaluation

OBJECTIVES

To evaluate how women access and engage with different models of maternity care, whether specialist models improve access and engagement for women with social risk factors, and if so, how?

DESIGN

Realist evaluation.

SETTING

Two UK maternity service providers.

PARTICIPANTS

Women accessing maternity services in 2019 (n=1020).

METHODS

Prospective observational cohort with multinomial regression analysis to compare measures of access and engagement between models and place of antenatal care. Realist informed, longitudinal interviews with women accessing specialist models of care were analysed to identify mechanisms.

MAIN OUTCOME MEASURES

Measures of access and engagement, healthcare-seeking experiences.

RESULTS

The number of social risk factors women were experiencing increased with deprivation score, with the most deprived more likely to receive a specialist model that provided continuity of care. Women attending hospital-based antenatal care were more likely to access maternity care late (risk ratio (RR) 2.51, 95% CI 1.33 to 4.70), less likely to have the recommended number of antenatal appointments (RR 0.61, 95% CI 0.38 to 0.99) and more likely to have over 15 appointments (RR 4.90, 95% CI 2.50 to 9.61) compared with community-based care. Women accessing standard care (RR 0.02, 95% CI 0.00 to 0.11) and black women (RR 0.02, 95% CI 0.00 to 0.11) were less likely to have appointments with a known healthcare professional compared with the specialist model. Qualitative data revealed mechanisms for improved access and engagement including self-referral, relational continuity with a small team of midwives, flexibility and situating services within deprived community settings.

CONCLUSION

Inequalities in access and engagement with maternity care appears to have been mitigated by the community-based specialist model that provided continuity of care. The findings enabled the refinement of a realist programme theory to inform those developing maternity services in line with current policy.

Hypertension prevalence, coding and control in an urban primary care setting in the UK between 2014 and 2021

OBJECTIVE

Hypertension is a leading preventable cause of mortality, yet high rates of undiagnosed and uncontrolled hypertension continue. The burden falls most heavily on some ethnic minorities and the socially deprived, with the COVID-19 pandemic having further widened inequalities. We sought to determine the prevalence and predictors of unmeasured blood pressure (BP), uncoded elevated BP and uncontrolled hypertension in primary care across 2014-2021.

METHODS

A population-based cohort study using data from all 41 general practices in a socioeconomically diverse inner-city borough. BP measurements, sociodemographic, lifestyle and clinical factors were extracted from anonymized primary care data. Hypertension and BP control were defined using NICE guidelines. Associations between patient characteristics and hypertension outcomes were identified using logistical regression modelling.

RESULTS

Of 549 082 patients, 39.5% had unmeasured BP; predictors included male sex [AOR 2.40, 95% confidence interval (95% CI) 2.26-2.43] and registration in the pandemic years. Of 71 970 adults with elevated BP, 36.0% were uncoded; predictors included obesity (AOR 2.51, 95% CI 2.42-2.60) and increasing age. Of 44 648 adults on the hypertension register, 46.8% had uncontrolled hypertension; predictors included black ethnicity compared to white (AOR 1.54, 95% CI 1.41-1.68) and cardiovascular co-morbidities (AOR 1.23, 95% CI 1.21-1.25). Social deprivation was only weakly or not significantly associated with hypertension outcomes.

CONCLUSION

The burden of uncoded elevated BP and uncontrolled hypertension is high. Obesity and male sex were associated with uncoded elevated BP and uncontrolled hypertension. Black ethnicity was associated with uncontrolled hypertension. Initiatives are needed to optimize hypertension coding and control, with an emphasis on specific population subgroups.