Comparison of central nervous system malformations in spontaneous absortions in Northern Ireland and south-east England

Burden of Neural Tube Defects and Their Associated Factors in Africa: A Systematic Review and Meta-Analysis

Background

Neural tube defects are a type of congenital anomaly caused by an abnormality in the development of the brain and spinal cord during embryogenesis. They cause high rates of mortality, morbidity, and lifelong disability. There are several studies carried out worldwide reporting different findings on the burden and associated factors. The aim of this study is to carry out a systematic review and meta-analysis of the burden of neural tube defects and their associated factors in Africa.

Methods

A total of 58 eligible articles were identified systematically using databases such as PubMed, Embase, African Journal Online Library, ProQuest, Cochrane, Google Scopus, Google Scholar, and Grey literature. Extracted data were analyzed using STATA 16.0 statistical software. The heterogeneity of studies was determined using the Cochrane Q test statistic and I² test statistics with forest plots. A random effects model was used to examine the pooled burden of neural tube defects, subgroups of the region, subtypes of NTDs, sensitivity analysis, and publication bias. The association between NTDs and associated factors was studied using a fixed-effect model.

Results

Fifty-eight studies with a total of 7,150,654 participants in 16 African countries revealed that the pooled burden of neural tube defects was 32.95 per 10,000 births (95% CI: 29.77-36.13). The Eastern African region had the highest burden in the subgroup analysis, with 111.13 per 10,000 births (95% CI: 91.85-130.42). South African countries had the lowest burden, at 11.43 per 10,000 births (95% CI: 7.51-15.34). In subtype analysis, spina bifida had the highest pooled burden at 17.01 per 10,000 births (95 percent CI: 15.00-19.00), while encephalocele had the lowest at 1.66 per 10,000 births (95% CI: 1.12-2.20). Maternal folic acid supplementation (AOR: 0.38; 95% CI: 0.16-0.94), alcohol consumption (AOR: 2.54; 95% CI: 1.08-5.96), maternal age (AOR: 3.54; 95% CI: 1.67-7.47), pesticide exposure (AOR: 2.69; 95% CI: 1.62-4.46), X-ray radiation (AOR: 2.67; 95% CI: 1.05-6.78), and history of stillbirth (AOR: 3.18; 95% CI: 1.11-9.12) were significantly associated with NTDs.

Conclusion

The pooled burden of NTDs in Africa was found to be high. Maternal age, alcohol consumption, pesticide and X-ray radiation exposure, history of stillbirth, and folic acid supplementation were significantly associated with NTDs.

Prevention of neural tube defects by the fortification of flour with folic acid: a population-based retrospective study in Brazil

Objective

To determine if the fortification of wheat and maize flours with iron and folic acid – which became mandatory in Brazil from June 2004 – is effective in the prevention of neural tube defects.

Methods

Using data from national information systems on births in central, south-eastern and southern Brazil, we determined the prevalence of neural tube defects among live births and stillbirths in a pre-fortification period – i.e. 2001–2004 – and in a post-fortification period – i.e. 2005–2014. We distinguished between anencephaly, encephalocele, meningocele, myelomeningocele and other forms of spina bifida.

Findings

There were 8554 neural tube defects for 17 925 729 live births notified between 2001 and 2014. For the same period, 2673 neural tube defects were reported for 194 858 stillbirths. The overall prevalence of neural tube defects fell from 0.79 per 1000 pre-fortification to 0.55 per 1000 post-fortification (prevalence ratio, PR: 1.43; 95% confidence interval, CI: 1.38–1.50). For stillbirths, prevalence fell from 17.74 per 1000 stillbirths pre-fortification to 11.70 per 1000 stillbirths post-fortification. The corresponding values among live births were 0.57 and 0.44, respectively.

Conclusion

The introduction of the mandatory fortification of flour with iron and folic acid in Brazil was followed by a significant reduction in the prevalence of neural tube defects in our study area.

'Miscarriage or abortion?' Understanding the medical language of pregnancy loss in Britain; a historical perspective

Clinical language applied to early pregnancy loss changed in late twentieth century Britain when doctors consciously began using the term 'miscarriage' instead of 'abortion' to refer to this subject. Medical professionals at the time and since have claimed this change as an intuitive empathic response to women's experiences. However, a reading of medical journals and textbooks from the era reveals how the change in clinical language reflected legal, technological, professional and social developments. The shift in language is better understood in the context of these historical developments, rather than as the consequence of more empathic medical care for women who experience miscarriage.

Prevention of chronic kidney disease in spina bifida

OBJECTIVE

The prevalence of progressive chronic kidney disease (CKD) in children and adults with spina bifida is considerable, rising, and entirely preventable.

REMOVING THE CAUSE

PREVENTION OF SPINA BIFIDA: The best prevention of CKD in spina bifida is prevention of spina bifida itself through strategies that include folate supplementation, ideally before pregnancy.

THE CAUSE OF CKD

Dysfunctional bladder outlet causes febrile Urinary Tract Infections (UTI), even with clean intermittent catheterization (CIC), and subsequent renal scarring. The development of secondary vesicoureteric reflux (VUR) increases the risk of renal scarring and CKD.

FINDING THE IDEAL MARKER FOR MEASUREMENT OF RENAL FUNCTION IN SPINA BIFIDA

Creatinine-based methods are insensitive because of low muscle mass and underdeveloped musculature in the legs. Only Cystatin C-based eGFR can reliably assess global renal function in these patients. However, unilateral renal damage requires nuclear medicine scans, such as (99m)Tc DMSA. (VIDEO)URODYNAMICS STUDIES (UDS): Early treatment is recommended based on UDS with anticholinergics, CIC, and antibiotic prophylaxis when indicated. Overnight catheter drainage, Botox, and eventually augmentation cystoplasty are required for poorly compliant bladders. A continent child or one rendered continent following surgery is at a higher risk of renal damage.

CONCLUSION

A multidisciplinary approach is required to reduce the burden of CKD in patients with spina bifida. The right tools have to be utilized to monitor these patients, particularly if recurrent UTIs occur. Cystatin C eGFR is preferred for monitoring renal damage in these patients, and (99m)Tc DMSA scans have to be used to detect unilateral renal scarring.

Epidemiology of neural tube defects

Neural tube defects (NTDs)-malformations secondary to abnormal neural tube closure between the third and fourth weeks of gestational age-have a complex and imperfectly understood etiology in which both genetic and environmental factors appear to be involved. A number of specific chromosomal or single-gene disorders, presumably not affected by environmental influences, are associated with the development of NTDs, but such syndromal cases account for a small proportion of NTDs in live-born infants. Analysis of recurrence patterns within families and of twin-concordance data provides evidence of a genetic influence in nonsyndromal cases, but factors such as socioeconomic status and geographic area (independent of race or ethnicity) are also associated with variations in the incidence of NTDs. The prevalence at birth of both anencephaly and spina bifida has decreased, but the advent of antenatal diagnosis and elective termination of affected pregnancies has undermined the reliability of birth prevalence rate as an estimate of incidence. Some occupational and other exposures, including maternal use of antiepileptic drugs (AEDs), are associated with increased risk for NTDs. Among women who have had an NTD-affected pregnancy, recurrence risk is markedly higher than the risk for a first NTD-affected pregnancy in the general population. There is strong evidence, overall, for a protective effect of adequate folate consumption. In some high-risk groups, however, such as women taking AEDs, folate supplementation has not been proven to reduce NTD risk.

Neural tube defects in spontaneous abortions

Nine specimens with neural tube defects (NTDs) were ascertained in a consecutive series of spontaneous abortions in New York City, giving a rate of 10.2 per 1,000 testable embryos and fetuses. All seven successfully karyotyped abortions had a chromosome anomaly. The rate of NTDs in miscarriages in New York is only one-third the rate in miscarriages in London, and the difference is due entirely to a deficit of fetuses with normal chromosomes. Our data, together with data from three other centers, indicate that there is a strongly positive association (r = 0.96) between rates of neural tube defects in early pregnancy and at term. The implications of these findings for genetic counseling and for etiologic studies are discussed.

Sibs of probands with neural tube defects--a study in the Federal Republic of Germany

Data for the risk of neural tube defects in sibs of affected children are needed for genetic counselling, for decision on prenatal studies, and for planning of preventive measures. Data have been reported from various populations but were lacking for Germany. This study presents data on the siblings of 240 index patients in the Western part of the Federal Republic of Germany. The prevalence among sibs of affected individuals was found to be 2.6%. This figure agrees well with reports from other countries in Continental Europe and the United States, and fits the expectation of lower recurrence risks in low incidence populations.

Epidemiology of neural tube defects in Germany

A survey is made of the epidemiologic studies of neural tube defects (NTD) in Germany. A temporary increase is noted in the prevalence of NTD at birth for the time during and shortly after the Second World War, followed by a downward trend thereafter. Thus an earlier observation of Lenz (1965) could be confirmed. Falling rates of NTD were also reported from various other countries in recent years. No convincing etiological explanation is available so far. The current prevalence of NTD at birth can be estimated for Germany to be about 1.0-1.5 per thousand newborns with about an even distribution to anencephalus and spina bifida.

A family study of spina bifida and anencephalus in Belfast, Northern Ireland (1964 to 1968)

The parents of 226 of the 360 patients with anencephalus or spinal bifida or both, born in Belfast 1964 to 1968, were visited to document the occurrence of these malformations among other relatives. The proportions of sibs with anencephalus and spina bifida were 10.41% for spina bifida index patients and 6.4% for anencephalus. For patients born after the index patients, the proportions were 12.19% and 6.35%, respectively. The overall incidence of either malformation among sibs was 8.87%. This estimate is higher than the 4 to 5% commonly reported and is probably related to the specific background of the Northern Ireland population, which is known to have the highest incidence of CNS malformations in the United Kingdom. The substantial size of this risk indicates the importance of amniocentesis for monitoring subsequent pregnancies of women who have had one child with a CNS malformation.