The prevalence of congenital abnormalities in patients with positive contraction stress tests

Peer Reviewe

Analysis of two mutations in the MTHFR gene associated with mild hyperhomocysteinaemia – heterogeneous distribution in the South African population

Objective, The frequencies of mutations 677C→T and 1298A→C in the methylenetetrahydrofolate reductase (MTHFR) gene, previously shown to be associated with decreased enzyme activity that may lead to hyperhomocysteinaemia and consequently increased risk of cardiovascular disease (CVD), were determined in the South African population.Methods, Hinfi (677C→T) and MbolI (1298A→C) restriction enzyme analyses were performed on amplified DNA samples of 76 white, 73 coloured and 60 black subjects.Results, The mutant alleles of mutations 677C→T and 1298A..-+C were more common in the white (allele frequencies 0.36 and 0.37, respectively) than in the black population (0.04 and 0.09), while intermediate frequencies were detected in the coloured population (0,18 and 0.30); Homozygosity for mutation 677C → T was not detected in the black cohort, while this genotype was detected in 1 coloured (1.4%) and 8 white (105%) subjects, In the black population, 5% of the 60 subjects analysed were homozygous for mutation 1298A→C, compared with approximately 12% in both the white and coloured populations,Conclusions. Since hyperhomocysteinaemia is a risk factor for premature CVD, the heterogeneous distribution of the 677C→T and 1298A→C mutations across ethnic groups may partly explain ethnic differences in heart disease risk through decreased enzyme activity and hence increased homocysteine levels

Associations between prenatal alcohol and tobacco exposure on Doppler flow velocity waveforms in pregnancy: a South African study

Background The negative impact of prenatal alcohol and tobacco exposure (PAE and PTE) on fetal development and birth outcomes are well described, yet pathophysiologic mechanisms are less clear. Our aim was to investigate (1) the associations between quantity, frequency and timing (QFT) of PAE and PTE with blood flow velocities in arteries of the fetal-placental-maternal circulation and (2) the extent to which combined effect of QFT of PAE and/or PTE and Doppler flow velocity waveforms (FWV) predict infant birth weight. Methods The Safe Passage Study is a cohort based in urban Cape Town, South Africa. Recruitment occurred between 2007 and 2015. Information on QFT of PAE and PTE was collected prospectively at up to 4 occasions during pregnancy using a modified Timeline Follow-Back approach. Ultrasound examinations consisted of Doppler flow velocity waveforms of the uterine, umbilical (UA) and fetal middle cerebral arteries for the pulsatility index (PI) at 20–24 and 34–38 weeks. Exclusion criteria included: twin pregnancies, stillbirths, participants exposed to other drugs. The sample was divided into three groups (controls, PAE and PTE) and included 1396 maternal-fetal-dyads assessed during the second trimester; 1398 assessed during the third trimester. Results PTE was associated with higher UA PI values in second and third trimesters (p < 0.001), compared to the PAE and control group. The total amount of cigarettes smoked during pregnancy was positively correlated with UA PI values (r = 0.087, p < 0.001). There was a positive correlation between cigarettes smoked per day in trimester one (r = 0.091, p < 0.01), and trimester two (r = 0.075, p < 0.01) and UA PI (in trimester two), as well as cigarettes smoked per day in trimester two (r = 0.058, p < 0.05) and trimester three (r = 0.069, p < 0.05) and the UA PI in trimester three. Generalized additive models indicated that PAE in trimester two, PTE in trimester one and Doppler FWV in trimester three were significant predictors of birth weight in this sample. Conclusion In our study, PTE in trimesters two and three resulted in increased vascular resistance of the placenta. These findings highlight nuance in associations between PAE, PTE and blood flow velocities in arteries of the fetal-placental-maternal circulation and birth weight, suggesting that quantity and timing are important factors in these relationships

Transitional objects of grief

CITATION: Goldstein, Richard D. et al. 2020. Transitional objects of grief. Comprensive Psychiatry, 98:152161, doi:10.1016/j.comppsych.2020.152161.The original publication is available at: https://www.ncbi.nlm.nih.govBackground: Transitional objects provide security and symbolic connection with valued others when separated from them. Bereaved parents often keep, cherish and visit saved objects of their deceased child. This research examined the hypothesis that these objects behave as transitional objects of grief in bereaved mothers during three years following their infants' deaths from Sudden Infant Death Syndrome. Methods: Questionnaires were administered asking about the presence of kept objects and momentos from their deceased infant, and the frequency, location and emotions experienced during visits to them. Diagnostic criteria for Prolonged Grief Disorder (PGD) were assessed using the Parental Bereavement Questionnaire. Results: 98.6% of the mothers reported having transitional objects of grief, and most visited them more frequently than once per week regardless of PGD status. Mothers with PGD reported significantly more distress when visiting the objects, especially those visiting them privately. Mothers with PGD who felt comforted by the objects had lower risk for finding life meaningless or finding discussion about the infant intolerable. Conclusions: Transitional objects of grief are common and associated with key aspects of grief. There is a need to understand the potential therapeutic uses of transitional objects in promoting bereavement adjustment.Publisher's versio

Contextualizing the impact of prenatal alcohol and tobacco exposure on neurodevelopment in a South African birth cohort: an analysis from the socioecological perspective

BackgroundAlcohol and tobacco are known teratogens. Historically, more severe prenatal alcohol exposure (PAE) and prenatal tobacco exposure (PTE) have been examined as the principal predictor of neurodevelopmental alterations, with little incorporation of lower doses or ecological contextual factors that can also impact neurodevelopment, such as socioeconomic resources (SER) or adverse childhood experiences (ACEs). Here, a novel analytical approach informed by a socio-ecological perspective was used to examine the associations between SER, PAE and/or PTE, and ACEs, and their effects on neurodevelopment.MethodsN = 313 mother-child dyads were recruited from a prospective birth cohort with maternal report of PAE and PTE, and cross-sectional structural brain neuroimaging of child acquired via 3T scanner at ages 8–11 years. In utero SER was measured by maternal education, household income, and home utility availability. The child’s ACEs were measured by self-report assisted by the researcher. PAE was grouped into early exposure (&lt;12 weeks), continued exposure (&gt;=12 weeks), and no exposure controls. PTE was grouped into exposed and non-exposed controls.ResultsGreater access to SER during pregnancy was associated with fewer ACEs (maternal education: β = −0.293,p = 0.01; phone access: β = −0.968,p = 0.05). PTE partially mediated the association between SER and ACEs, where greater SER reduced the likelihood of PTE, which was positively associated with ACEs (β = 1.110,p = 0.01). SER was associated with alterations in superior frontal (β = −1336.036, q = 0.046), lateral orbitofrontal (β = −513.865, q = 0.046), caudal anterior cingulate volumes (β = −222.982, q = 0.046), with access to phone negatively associated with all three brain volumes. Access to water was positively associated with superior frontal volume (β=1569.527, q = 0.013). PTE was associated with smaller volumes of lateral orbitofrontal (β = −331.000, q = 0.033) and nucleus accumbens regions (β = −34.800, q = 0.033).ConclusionResearch on neurodevelopment following community-levels of PAE and PTE should more regularly consider the ecological context to accelerate understanding of teratogenic outcomes. Further research is needed to replicate this novel conceptual approach with varying PAE and PTE patterns, to disentangle the interplay between dose, community-level and individual-level risk factors on neurodevelopment

Stillbirth rates in singleton pregnancies in a stable population at Karl Bremer and Tygerberg hospitals over 50 years

CITATION: Odendaal, H. J., Gebhardt, G. S. & Theron, G. B. 2013. Stillbirth rates in singleton pregnancies in a stable population at Karl Bremer and Tygerberg hospitals over 50 years. South African Journal of Obstetrics and Gynaecology, 19(3):67-70, doi:10.7196/SAJOG.662.The original publication is available at http://www.sajog.org.zaObjectives. To determine the changes in stillbirth rates in singleton pregnancies in a stable population over a period of 50 years. Methods. Stillbirth rates for singleton pregnancies where the fetus weighed 1 000 g or more were collected from 1962 to 2011. From 1972 to 2011, rates included fetuses weighing 500 g or more at birth. Results. When the birth weight was 1 000 g or more the stillbirth rate declined from 70 to 12.6 per 1 000 births, and when the birth weight was 500 g or more it dropped from 34.2 to 24.5. The decline was very much slower towards the end of the study period. Conclusion. To achieve further sustained reductions in stillbirth rates, healthcare workers should continue to emphasise quality of healthcare, but they should also address and prevent specific conditions associated with stillbirth, such as smoking and drinking during pregnancy.http://www.sajog.org.za/index.php/SAJOG/article/view/662Publisher's versio

Lipoprotein(a) determination and risk of cardiovascular disease in South African patients with familial hypercholesterolaemia

CITATION: Scholtz, C. L. et al 2000. Lipoprotein(a) determination and risk of cardiovascular disease in South African patients with familial hypercholesterolaemia. South African Medical Journal, 90(4):374-378.The original publication is available at http://www.samj.org.zaObjective. A raised plasma level of lipoprotein(a) (Lp(a)) is an established genetic risk factor for coronary heart disease (CHD), particularly in patients with concomitant elevation of low-density lipoprotein (LDL) cholesterol. The current study focused on the comparison of two commercially available Lp(a) assay kits to determine whether differences observed in measured Lp(a) levels could be deemed negligible in CHD risk assessment in familial hypercholesterolaemic (FH) patients. Design. To compare results obtained on duplicate plasma samples using two commercially available Lp(a) measuring kits, the immunoradiometric assay (RIA) and the enzyme-linked immunoabsorbent assay (ELISA). Setting. Division of Human Genetics, Department of Obstetrics and Gynaecology, University of Stellenbosch, Tygerberg, South Africa and the Institute for Medical Biology and Human Genetics, University of Innsbruck, Austria. Subjects. Plasma samples were obtained from 146 family members of 65 molecularly characterised South African FH families for comparative analysis. Results. Using the RIA method, 34 samples (23%) considered to be in the normal range by the ELISA technique, were placed in the high-risk group (> 30 mg/dl). Only one sample, considered to have a normal Lp(a) level with the RIA method, was categorised by the ELISA technique as high risk. Conclusion. Our data demonstrate that measurements of Lp(a) using the RIA method (the only assay available in South Africa at the time of this study) differ significantly from those obtained by the reference ELISA technique, suggesting that misclassification could lead to inaccurate CHD risk assessment. This is an important consideration in Afrikaner FH families, where plasma levels of Lp(a) have been shown to be elevated significantly in FH patients compared with non-FH individuals.Publisher’s versio

Alcohol exposure before and during pregnancy is associated with reduced fetal growth: the Safe Passage Study

Abstract Background Prenatal alcohol exposure (PAE) is a worldwide public health concern. While PAE is known to be associated with low birth weight, little is known about timing and quantity of PAE on fetal growth. This study investigated the association between periconceptional and prenatal alcohol exposure and longitudinal fetal growth, focusing on timing and quantity in a high exposure cohort. Methods The Safe Passage Study was a prospective cohort study, including 1698 pregnant women. Two-dimensional transabdominal ultrasound examinations were performed to measure fetal femur length, abdominal and head circumference, and biparietal diameter, at three time points during pregnancy. Estimated fetal weight and Z-scores of all parameters were calculated. Trimester-specific alcohol exposure was assessed using the Timeline Followback method. To investigate the associations of specific timing of PAE and fetal growth, two models were built. One with alcohol exposure as accumulative parameter over the course of pregnancy and one trimester specific model, in which PAE was separately analyzed. Linear mixed models adjusted for potential confounders were applied with repeated assessments of both alcohol exposure and fetal growth outcomes. Results This study demonstrated that periconceptional and prenatal alcohol exposure were associated with reduced fetal growth. Effect sizes are displayed as estimated differences (ED) in Z-score and corresponding 95% confidence intervals (95% CIs). When investigated as accumulative parameter, PAE was related to a smaller femur length (ED 30 ; − 0.13 (95% CI; − 0.22; − 0.04), ED 36 ; − 0.14 (95% CI; − 0.25; − 0.04)) and a smaller abdominal circumference (ED 36 ; − 0.09 (95% CI; − 0.18; − 0.01)). Periconceptional alcohol exposure was associated with a smaller abdominal circumference (ED 30 ; − 0.14 (95% CI; − 0.25; − 0.02), ED 36 ; − 0.22 (95% CI; − 0.37; − 0.06)) and a smaller estimated fetal weight (ED 36 ; − 0.22 (95% CI; − 0.38; − 0.05)). Second trimester alcohol exposure was associated with a smaller abdominal circumference (ED 30 ; − 0.49 (95% CI; − 0.86; − 0.12), ED 36 ; − 0.70 (95% CI; − 1.22; − 0.17)) and estimated fetal weight (ED 30 ; − 0.54 (95% CI; − 0.94; − 0.14), ED 36 ; − 0.69 (95% CI; − 1.25; − 0.14)). No additional association of binge drinking was found besides the already observed association of PAE and fetal growth. Conclusions This study demonstrated that PAE negatively affects fetal growth, in particular when exposed during the periconception period or in second trimester. Our results indicate that potential negative consequences of PAE are detectable already before birth. Therefore, healthcare providers should actively address and discourage alcohol use during pregnancy