The Association of Prenatal Diagnoses with Mortality and Long-Term Morbidity in Children with Specific Isolated Congenital Anomalies: A European Register-Based Cohort Study

OBJECTIVES

To compare 5-year survival rate and morbidity in children with spina bifida, transposition of great arteries (TGA), congenital diaphragmatic hernia (CDH) or gastroschisis diagnosed prenatally with those diagnosed postnatally.

METHODS

Population-based registers' data were linked to hospital and mortality databases.

RESULTS

Children whose anomaly was diagnosed prenatally (n = 1088) had a lower mean gestational age than those diagnosed postnatally (n = 1698) ranging from 8 days for CDH to 4 days for TGA. Children with CDH had the highest infant mortality rate with a significant difference (p < 0.001) between those prenatally (359/1,000 births) and postnatally (116/1,000) diagnosed. For all four anomalies, the median length of hospital stay was significantly greater in children with a prenatal diagnosis than those postnatally diagnosed. Children with prenatally diagnosed spina bifida (79% vs 60%; p = 0.002) were more likely to have surgery in the first week of life, with an indication that this also occurred in children with CDH (79% vs 69%; p = 0.06).

CONCLUSIONS

Our findings do not show improved outcomes for prenatally diagnosed infants. For conditions where prenatal diagnoses were associated with greater mortality and morbidity, the findings might be attributed to increased detection of more severe anomalies. The increased mortality and morbidity in those diagnosed prenatally may be related to the lower mean gestational age (GA) at birth, leading to insufficient surfactant for respiratory effort. This is especially important for these four groups of children as they have to undergo anaesthesia and surgery shortly after birth. Appropriate prenatal counselling about the time and mode of delivery is needed.

Educational achievement of children with selected major congenital anomalies and associated factors: a Finnish registry-based study

BACKGROUND

Children with major congenital anomalies may be at risk of poor educational outcomes. We aimed to evaluate the educational achievement of children born with major congenital anomalies compared with children without major congenital anomalies in relation to sociodemographic factors.

METHODS

We performed a registry-based study including 401 544 children in Finland, graduates of the compulsory school who applied to secondary education. We used health data from the Finnish Register of Congenital Malformations for children born from 1995 to 2002 linked with education data from the Finnish Ministry of Education and Culture. We used generalized linear regression to compare the mean grade differences of children with specific major congenital anomalies and 'All anomalies' subgroup (major congenital anomalies, chromosomal syndromes, and multiple anomalies) with reference children.

RESULTS

Children with major congenital anomalies were less likely to apply for further education than reference children (88.0% vs. 96.8%; odds ratio = 4.13; 95% confidence interval, 3.92-4.36). For most non-chromosomal congenital anomalies, children born with congenital anomalies had similar educational achievement to the reference children. For the 'All anomalies' subgroup, children with congenital anomalies had lower educational achievement than reference children. Among children with congenital anomalies, male sex, lower maternal educational levels and younger maternal age were associated with lower educational achievement.

CONCLUSIONS

For children applying to further education, most non-chromosomal congenital anomalies were not associated with lower educational achievement. Nevertheless, efforts are needed to improve educational achievement in children with major congenital anomalies associated with maternal sociodemographic background.

Ethics and legal requirements for data linkage in 14 European countries for children with congenital anomalies

INTRODUCTION

Linking healthcare data sets can create valuable resources for research, particularly when investigating rare exposures or outcomes. However, across Europe, the permissions processes required to access data can be complex. This paper documents the processes required by the EUROlinkCAT study investigators to research the health and survival of children with congenital anomalies in Europe.

METHODS

Eighteen congenital anomaly registries in 14 countries provided information on all the permissions required to perform surveillance of congenital anomalies and to link their data on live births with available vital statistics and healthcare databases for research. Small number restrictions imposed by data providers were also documented.

RESULTS

The permissions requirements varied substantially, with certain registries able to conduct congenital anomaly surveillance as part of national or regional healthcare provision, while others were required to obtain ethics approvals or informed consent. Data linkage and analysis for research purposes added additional layers of complexity for registries, with some required to obtain several permissions, including ethics approvals to link the data. Restrictions relating to small numbers often resulted in a registry's data on specific congenital anomalies being unusable.

CONCLUSION

The permissions required to obtain and link data on children with congenital anomalies varied greatly across Europe. The variation and complexity present a significant obstacle to the use of such data, especially in large data linkage projects. Furthermore, small number restrictions severely limited the research that could be performed for children with specific rare congenital anomalies.

Prescription of cardiovascular medication in children with congenital heart defects across six European Regions from 2000 to 2014: data from the EUROlinkCAT population-based cohort study

OBJECTIVES

Advances in surgical management strategies have substantially reduced fatality from congenital heart defects (CHD). Decreased infant mortality might be expected, consequentially to result in greater morbidity in older children due to complications later in childhood and adolescence. This study aims to evaluate the use of cardiovascular medication (CVM) as an indicator of disease burden in children born with CHD in the first 10 years of life.

DESIGN

Population-based cohort study.

SETTING

Six population-based registries from the European Surveillance of Congenital Anomalies (EUROCAT) network participated. Data from live born children with major congenital anomalies (CA) born from 2000 to 2014 were linked to prescription databases. Four groups of children were analysed: CA, CHD, severe CHD (sCHD) and ventricular septal defect (VSD) without sCHD. Live born children without CA were included as reference group.

PARTICIPANTS

We obtained data on 61 038 children born with a CA, including 19 678 with CHD, 3392 with sCHD, 12 728 children with VSD without sCHD, and 1 725 496 reference children.

RESULTS

Children born with sCHD were the most likely to receive a CVM prescription (42.9%, 95% CI, 26.3 to 58.5) in the first year of life compared with 13.3% (6.7 to 22.0) of children with any CHD, 5.9% (3.7 to 8.7) of children with any CA and 0.1% (0.0 to 0.1) of reference children. Medication was less likely to be prescribed after the first year of life for sCHD; 18.8% (14.8 to 23.1) for children 1-4 years and 15.8% (12.0 to 20.1) 5-9 years. Children with sCHD were most likely to receive a diuretic (36.4%, 18.6 to 54.5), an antihypertensive (6.9%, 3.7 to 11.3) or a beta-blocker (5.5%, 2.9 to9.2).

CONCLUSION

Almost half of all children with sCHD were prescribed CVM in their first year of life. For all four groups of children with anomalies, the proportion of children with a CVM prescription decreased with age.

Survival of children with rare structural congenital anomalies: a multi-registry cohort study

BACKGROUND

Congenital anomalies are the leading cause of perinatal, neonatal and infant mortality in developed countries. Large long-term follow-up studies investigating survival beyond the first year of life in children with rare congenital anomalies are costly and sufficiently large standardized cohorts are difficult to obtain due to the rarity of some anomalies. This study aimed to investigate the survival up to 10 years of age of children born with a rare structural congenital anomaly in the period 1995-2014 in Western Europe.

METHODS

Live births from thirteen EUROCAT (European network for the epidemiological surveillance of congenital anomalies) population-based registries were linked to mortality records. Survival for 12,685 live births with one of the 31 investigated rare structural congenital anomalies (CAs) was estimated at 1 week, 4 weeks and 1, 5 and 10 years of age within each registry and combined across Europe using random effects meta-analyses. Differences between registries were evaluated for the eight rare CAs with at least 500 live births.

RESULTS

Amongst the investigated CAs, arhinencephaly/holoprosencephaly had the lowest survival at all ages (58.1%, 95% Confidence Interval (CI): 44.3-76.2% at 1 week; 47.4%, CI: 36.4-61.6% at 1 year; 35.6%, CI: 22.2-56.9% at 10 years). Overall, children with rare CAs of the digestive system had the highest survival (> 95% at 1 week, > 84% at 10 years). Most deaths occurred within the first four weeks of life, resulting in a 10-year survival conditional on surviving 4 weeks of over 95% for 17 out of 31 rare CAs. A moderate variability in survival between participating registries was observed for the eight selected rare CAs.

CONCLUSIONS

Pooling standardised data across 13 European CA registries and the linkage to mortality data enabled reliable survival estimates to be obtained at five ages up to ten years. Such estimates are useful for clinical practice and parental counselling.

Linking a European cohort of children born with congenital anomalies to vital statistics and mortality records: A EUROlinkCAT study

EUROCAT is a European network of population-based congenital anomaly (CA) registries. Twenty-one registries agreed to participate in the EUROlinkCAT study to determine if reliable information on the survival of children born with a major CA between 1995 and 2014 can be obtained through linkage to national vital statistics or mortality records. Live birth children with a CA could be linked using personal identifiers to either their national vital statistics (including birth records, death records, hospital records) or to mortality records only, depending on the data available within each region. In total, 18 of 21 registries with data on 192,862 children born with congenital anomalies participated in the study. One registry was unable to get ethical approval to participate and linkage was not possible for two registries due to local reasons. Eleven registries linked to vital statistics and seven registries linked to mortality records only; one of the latter only had identification numbers for 78% of cases, hence it was excluded from further analysis. For registries linking to vital statistics: six linked over 95% of their cases for all years and five were unable to link at least 85% of all live born CA children in the earlier years of the study. No estimate of linkage success could be calculated for registries linking to mortality records. Irrespective of linkage method, deaths that occurred during the first week of life were over three times less likely to be linked compared to deaths occurring after the first week of life. Linkage to vital statistics can provide accurate estimates of survival of children with CAs in some European countries. Bias arises when linkage is not successful, as early neonatal deaths were less likely to be linked. Linkage to mortality records only cannot be recommended, as linkage quality, and hence bias, cannot be assessed.

Second-generation antipsychotic use during pregnancy and risk of congenital malformations

Purpose

To study if second-generation antipsychotic (S-GA) use during the first trimester of pregnancy is associated with an increased risk of major congenital malformations (MCM).

Methods

A population-based birth cohort study using national register data extracted from the Drugs and Pregnancy database in Finland, years 1996–2017. The sampling frame included 1,273,987 pregnant women. We included singleton pregnancies ending in live or stillbirth or termination of pregnancy due to severe malformation. Pregnancies with exposure to known teratogens were excluded. Women were categorized into three groups: exposed to S-GAs (n = 3478), exposed to first-generation antipsychotics (F-GAs) (n = 1030), and unexposed (no purchases of S-GAs or F-GAs during pregnancy, n = 22,540). We excluded genetic conditions and compared the prevalence of MCMs in S-GA users to the two comparison groups using multiple logistic regression models.

Results

Use of S-GAs during early pregnancy was not associated with an increased risk of overall MCMs compared to unexposed (adjusted odds ratio, OR 0.92; 95% CI 0.72–1.19) or to F-GA users (OR 0.82; 95% CI 0.56–1.20). Of individual S-GAs, olanzapine use was associated with an increased risk of overall MCMs (OR 2.12; 95% CI 1.19–3.76), and specifically, an increased risk of musculoskeletal malformations (OR 3.71; 95% CI 1.35–10.1) when compared to unexposed, while comparisons to F-GA users did not show significant results.

Conclusions

Olanzapine use is associated with an increased risk of major congenital malformations and specifically, musculoskeletal malformations. Use during pregnancy should be restricted to situations where no safer alternatives exist.

Supplementary information

The online version contains supplementary material available at 10.1007/s00228-021-03169-y.

Prevention of Neural Tube Defects in Europe: A Public Health Failure

Objective: Thirty years ago it was demonstrated that folic acid taken before pregnancy and in early pregnancy reduced the risk of a neural tube defect (NTD). Despite Public Health Initiatives across Europe recommending that women take 0.4 mg folic acid before becoming pregnant and during the first trimester, the prevalence of NTD pregnancies has not materially decreased in the EU since 1998, in contrast to the dramatic fall observed in the USA. This study aimed to estimate the number of NTD pregnancies that would have been prevented if flour had been fortified with folic acid in Europe from 1998 as it had been in the USA. Design and Setting: The number of NTD pregnancies from 1998 to 2017 that would have been prevented if folic acid fortification had been implemented in the 28 countries who were members of the European Union in 2019 was predicted was predicted using data on NTD prevalence from 35 EUROCAT congenital anomaly registries and literature searches for population serum folate levels and folic acid supplementation. Results: From 1998 to 2017 an estimated 95,213 NTD pregnancies occurred amongst 104 million births in the 28 countries in the EU, a prevalence of 0.92 per 1,000 births. The median serum folate level in Europe over this time period was estimated to be 14.1 μg/L. There is a lack of information about women taking folic acid supplements before becoming pregnant and during the first trimester of pregnancy, with one meta-analysis indicating that around 25% of women did so. An estimated 14,600 NTD pregnancies may have been prevented if the European countries had implemented fortification at the level adopted by the USA in 1998 and 25% of women took folic acid supplements. An estimated 19,500 NTD pregnancies would have been prevented if no women took folic acid supplements. Conclusions: This study suggests that failure to implement mandatory folic acid fortification in the 28 European countries has caused, and continues to cause, neural tube defects to occur in almost 1,000 pregnancies every year.

No MSH6 germline mutations in breast cancer families with colorectal and/or endometrial cancer

BACKGROUND

The genetic background in breast cancer families with colorectal and/or endometrial cancer is mostly unknown. The functional connection between MSH6 and the known breast cancer predisposition gene product BRCA1 suggests that the MSH6 gene may also play a role in breast cancer predisposition.

METHODS

We analysed 38 breast cancer families with colorectal and/or endometrial cancer for germline mutations in MSH6.

RESULTS

No disease associated mutations were detected among the breast cancer families. However, mutation analysis revealed a Glu995STOP mutation in an atypical HNPCC family. The same mutation was found in a patient with both breast and colorectal carcinoma in our previous study, and haplotype analysis confirmed a common ancestral origin. The Glu995STOP mutation was further examined in an extensive series of 245 colorectal and 142 breast carcinoma patients with a family history of breast, colorectal, and/or endometrial carcinoma, and in 268 healthy population controls, but none was found to carry the mutation.

CONCLUSIONS

Our results suggest that MSH6 may not be the underlying gene in breast cancer families with a history of colorectal and/or endometrial cancer. The Glu995STOP founder mutation is not a familial breast cancer predisposition allele and makes only a limited contribution to colorectal cancer burden in Finland.

Prognostic impact of chromosomal aberrations in Ewing tumours

Although greater than 50% of Ewing tumours contain non-random cytogenetic aberrations in addition to the pathognomonic 22q12 rearrangements, little is known about their prognostic significance. To address this question, tumour samples from 134 Ewing tumour patients were analysed using a combination of classical cytogenetics, comparative genomic and fluorescence in situ hybridisation. The evaluation of the compiled data revealed that gain of chromosome 8 occurred in 52% of Ewing tumours but was not a predictive factor for outcome. Gain of 1q was associated with adverse overall survival and event-free survival in all patients, irrespective of whether the tumour was localised or disseminated (overall survival: P=0.002 and P=0.029; event-free survival: P=0.018 and P=0.010). Loss of 16q was a significant predictive factor for adverse overall survival in all patients (P=0.008) and was associated with disseminated disease at diagnosis (P=0.039). Gain of chromosome 12 was associated with adverse event-free survival (P=0.009) in patients with localised disease. These results indicate that in addition to a 22q12 rearrangement confirmation in Ewing tumours it is important to assess the copy number of 1q and 16q to identify patients with a higher probability of adverse outcome.

Concomitant DNA copy number amplification at 17q and 22q in dermatofibrosarcoma protuberans

Dermatofibrosarcoma protuberans (DFSP) is a tumor of low or intermediate malignant potential with a tendency for recurrence, but low rate of metastasis. The tumorigenesis of DFSP has recently been shown to be associated with the fusion of the collagen type I alpha 1 (COL1A1) and platelet-derived growth factor B-chain (PDGFB) genes, often as a consequence of translocation t(17;22)(q22;q13). Cytogenetically, DFSP is often characterized by supernumerary ring chromosomes containing material from chromosomes 17 and 22. A subset of DFSPs undergo fibrosarcomatous transformation de novo or upon recurrence, and contain components indistinguishable from fibrosarcoma (FS-DFSP). The fibrosarcomatous transformation appears to carry an increased risk for recurrence and metastasis, and is considered to represent tumor progression. The molecular cytogenetic events contributing to tumor progression are unknown. We used comparative genomic hybridization to analyze DNA copy number changes in 11 cases of typical DFSP and 10 cases of FS-DFSP. All cases in both groups were found to exhibit a gain or high-level amplification on chromosome 17q and the majority also on 22q. This finding is in line with previous studies, and suggests further that not only the COL1A1/PDGFB fusion gene formation but also the role of DNA copy number gains in the 17q and 22q regions is crucial per se in the pathogenesis of DFSP. Even though FS-DFSPs displayed a trend toward increase in the number of DNA copy number changes, the difference was not statistically significant, which indicates that mechanisms other than copy number changes are important in the transformation process of DFSP.

FGF4 and INT2 oncogenes are amplified and expressed in Kaposi's sarcoma

Kaposi's sarcoma (KS) is a vascular tumor, the pathogenesis of which has been suggested to include human herpesvirus 8 (HHV-8) as well as various cytokines and growth factors. Very little is known about cytogenetic and molecular genetic changes in KS. We studied DNA copy number changes in KS and found a recurrent gain at 11q13. We then analyzed the amplification and expression status of two known oncogenes, FGF4 and INT2, residing at 11q13. Comparative genomic hybridization, interphase fluorescence in situ hybridization with yeast artificial chromosome probes containing FGF4 and INT2, and immunoperoxidase immunostaining with anti-FGF4 and -INT2 antibodies were used on 12 KS samples. All samples tested were shown by polymerase chain reaction to be HHV-8 positive. A recurrent gain at 11q13 was shown by comparative genomic hybridization in 4 of 10 cases studied. Of six cases studied by interphase fluorescence in situ hybridization, four showed a 3- to 4-fold amplification with the probes containing FGF4 and INT2. Expression of FGF4 and INT2 was found in nine and three cases, respectively, of nine studied. Amplification and expression of these genes is particularly interesting in the context of oncovirus involvement, because INT2 is a homolog of mouse int2 which causes mammary carcinoma in mice when activated by integration of retrovirus mouse mammary tumor virus. This raises the question of whether HHV-8 represents an integrating oncovirus that causes amplification and activation of genomic oncogenes in humans.

Clinical correlations of genetic changes by comparative genomic hybridization in Ewing sarcoma and related tumors

Our previous comparative genomic hybridization (CGH) study of Ewing sarcoma and related tumors showed that DNA sequence copy number increases of 1q21-q22 and of chromosomes 8 and 12 were associated with trends toward poor survival (Armengol et al., Br J Cancer 1997, 75, 1403-1409). These trends were not statistically significant. In the present study, we analyzed 28 primary Ewing sarcomas and related tumors by CGH to study whether these (or other) changes have prognostic value in these tumors. Twenty-one tumors (75%) had changes with a mean of 1.9 changes per tumor. The most frequent aberration was gain of chromosome 8 in 10 tumors (36%). Five tumors (18%) had copy number increases at 1q21-22 and 5 had gain of 7q. Copy number increase of 6p21.1-pter, gain of chromosome 12, and loss of 16q were seen in 11%. Copy number increases of 1q21-q22 and of chromosomes 8 and 12 were associated with trends toward worse outcome, but the differences did not reach statistical significance. A novel finding is the association of copy number increase at 6p with worse distant disease-free (P = 0.04) and overall survival (P = 0.004). To confirm this finding and to see whether copy number increases of 1q21-q22 and of chromosomes 8 and 12 have definite prognostic value, a larger number of cases needs to be studied.

DNA copy number losses in human neoplasms

This review summarizes reports of recurrent DNA sequence copy number losses in human neoplasms detected by comparative genomic hybridization. Recurrent losses that affect each of the chromosome arms in 73 tumor types are tabulated from 169 reports. The tables are available online at http://www.amjpathol.org and http://www. helsinki.fi/ approximately lglvwww/CMG.html. The genes relevant to the lost regions are discussed for each of the chromosomes. The review is supplemented also by a list of known and putative tumor suppressor genes and DNA repair genes (see Table 1, online). Losses are found in all chromosome arms, but they seem to be relatively rare at 1q, 2p, 3q, 5p, 6p, 7p, 7q, 8q, 12p, and 20q. Losses and their minimal common overlapping areas that were present in a great proportion of the 73 tumor entities reported in Table 2 (see online) are (in descending order of frequency): 9p23-p24 (48%), 13q21 (47%), 6q16 (44%), 6q26-q27 (44%), 8p23 (37%), 18q22-q23 (37%), 17p12-p13 (34%), 1p36.1 (34%), 11q23 (33%), 1p22 (32%), 4q32-qter (31%), 14q22-q23 (25%), 10q23 (25%), 10q25-qter (25%),15q21 (23%), 16q22 (23%), 5q21 (23%), 3p12-p14 (22%), 22q12 (22%), Xp21 (21%), Xq21 (21%), and 10p12 (20%). The frequency of losses at chromosomes 7 and 20 was less than 10% in all tumors. The chromosomal regions in which the most frequent losses are found implicate locations of essential tumor suppressor genes and DNA repair genes that may be involved in the pathogenesis of several tumor types.

DNA copy number changes in alveolar soft part sarcoma: a comparative genomic hybridization study

Alveolar soft part sarcoma (ASPS) is a rare, histologically distinctive soft tissue sarcoma typically occurring in children and young adults. Although the tumor often shows focal expression of muscle markers, its relationship with rhabdomyosarcoma is not established. The genetic background of ASPS is poorly understood. This study was undertaken to analyze the DNA copy number changes in 13 cases of ASPS using comparative genomic hybridization (CGH) on formaldehyde-fixed, paraffin-embedded tissue sections. Four ASPS cases showed DNA copy number changes. Gains were more common than losses. Gains observed in more than one case included 1q, 8q, 12q and 16p. Although these findings do not show consistent DNA copy number changes in ASPS, they give preliminary clues to genomic areas that might be important in the pathogenesis of ASPS.

Evidence for two molecular steps in the pathogenesis of myeloid disorders associated with deletion of chromosome 7 long arm

Partial deletion of the long arm of chromosome 7 (7q-) is a frequent chromosomal aberration in many neoplasias, including acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS). Recurrent deletions, leading to loss of heterozygosity (LOH), may be indicative of a tumor suppressor gene nearby. We studied eight AML or MDS patients with 7q-, in order to define the commonly deleted area in more detail. Separated blood lymphocytes and granulocytes were typed with 48 polymorphic microsatellite markers, and the heterozygosity between the two cell lineages was compared. The minimum commonly deleted region spanned from D7S658 to D7S655. Unexpectedly, four of the patients showed remarkable homozygosity in both lymphocytes and granulocytes around the commonly deleted area, and thus no deletions could be demonstrated by comparing the two cell lineages. Comparison to leukemic patients without 7q- and to normal individuals revealed that the homozygosity was restricted to patients with 7q-. We suggest that a specific mechanism, such as mitotic recombination in bone marrow stem cells, leading to homozygosity in both granulocytes and lymphocytes, represents a leukemogenetic step in these patients.