Consanguinity and birth defects in the jerusalem perinatal study cohort

CONSANGUINITY BY RANDOM ISONYMY AND SOCIOECONOMIC DEVELOPMENT IN ARGENTINA: A POPULATION STUDY

In human populations various flexible, labile and interdependent structures (genetic, demographic, socioeconomic) co-exist, each of which can be organized in an hierarchical order corresponding to administrative entities. The relationship between consanguinity, as estimated by random isonymy (F ST), and socioeconomic conditions was analysed at different levels of political and administrative organization in Argentina. From the surnames of 22,666,139 voters from the 2001 electoral roll, F ST was estimated for 510 Argentinian departments. Using a principal component analysis, a Socio-Demographic and Economic Indicator (SDEI), summarizing the effect of 22 socioeconomic and demographic variables at the departmental level, was computed. The relationship between departmental F ST and SDEI values was analysed for the whole nation and within regions using multiple regression analysis. The F ST presented a clinal distribution with the highest values in the north and west of the country, while SDEI expressed the opposite behaviour. A negative and significant correlation was observed between F ST and SDEI, accounting for 46% of the variation in consanguinity in Argentina. The strongest correlations of F ST with SDEI were observed in the Central, Patagonia and Cuyo regions, i.e. those with the highest values of SDEI and lowest values of F ST.

The Implications of Parental Consanguinity on the Care of Neonates

BACKGROUND

Approximately 6% of births worldwide, 7.9 million children, are born with a serious genetic congenital abnormality each year. A factor thought to increase the prevalence of birth defects is parental consanguinity, which is a social custom practiced in at least 20% of the world's population.

PURPOSE

The purpose of this article is to explore the relationship between consanguinity and congenital defects. This article also aims to enhance neonatal healthcare practitioners' comprehension of its implications for practice and research.

METHODS

A review of literature was compiled from a search of the online databases Cumulative Index of Nursing and Allied Health (CINAHL), PubMed, EBSCO MegaFILE, and Google Scholar.

RESULTS

Literature pertinent to this topic primarily consists of research studies that examine the inbreeding depression phenomenon through comparison of the prevalence of birth defects among the offspring of consanguineous and nonconsanguineous couples. Current studies indicate that the progeny of consanguineous couples are at an increased risk of congenital defects compared with those of nonconsanguineous couples.

IMPLICATIONS FOR PRACTICE

Consanguinity is one risk factor among many that can lead to a major birth defect. Relationships between consanguineous populations and neonatal healthcare practitioners such as registered nurses, advanced practice nurses, and physicians could significantly alter neonatal health outcomes. Specific recommendations such as genetic counseling and therapeutic communication are discussed.

IMPLICATIONS FOR RESEARCH

Further studies need to investigate the connection between consanguinity and birth defects while controlling for nongenetic variables. Moreover, a focus on consanguineous communities in the United States would prove beneficial.

Understanding utilization of outpatient clinics for children with special health care needs in southern Israel

To understand the pattern of utilization of ambulatory care by parents of children with special health care needs (CSHCN) and to explore parental challenges in coping with health maintenance of their infants after discharge from a neonatal intensive care unit (NICU). CSHCN require frequent utilization of outpatient ambulatory clinics especially in their first years of life. Multiple barriers are faced by families in disadvantaged populations which might affect adherence to medical referrals. Our study attempts to go beyond quantitative assessment of adherence rates, and capture the influence of parental agency as a critical factor ensuring optimal utilization of healthcare for CSHCN. A prospective, mixed-methods, cohort study followed 158 Jewish and Bedouin-Arab infants in the first year post discharge from NICU in southern Israel. Rates of utilization of ambulatory clinics were obtained from medical records, and quantitative assessment of factors affecting it was based on structured interviews with parents at baseline. Qualitative analysis was based on home visits or telephone in-depth interviews conducted about 1 year post-discharge, to obtain a rich, multilayered, experiential perspectives and explained perceptions by parents. Adherence to post-discharge referrals was generally good, but environmental, cultural, and financial obstacles to healthcare, magnified by communication barriers, forced parents with limited resources to make difficult choices affecting utilization of healthcare services. Improving concordance between primary caregivers and health care providers is crucial, and further development of supportive healthcare for CSHCN in concordance with parental limitations and preferences is needed.

Stillbirth and congenital anomalies in migrants in Europe

The risk of giving birth to a stillborn child or a child with severe congenital anomaly is higher for women who have immigrated to Europe as compared to the majority population in the receiving country. The literature, however, reveals great differences between migrant groups, even within migrants from low-income countries, although there is no clear pattern regarding refugee or non-refugee status. This heterogeneity argues against a particular migration-related explanation. There are social disparities in stillbirth risk worldwide, and it has been suggested that the demonstrated ethnic disparity is a result of the socioeconomic disadvantage most migrants face. Consanguinity has been considered as another cause for the increased stillbirth risk and the high risk of congenital anomaly observed in many migrant groups. Utilization and quality of care during pregnancy and childbirth is the third major aspect. All three factors seem to contribute to stillbirth risk, and they should be considered in clinical practice and public health.

A Register-Based Study of Diseases With an Autosomal Recessive Origin in Small Children in Denmark According to Maternal Country of Origin

BACKGROUND

Compared with children born of Danish mothers, the mortality of children, born and living in Denmark, is significantly increased in those with a mother from Afghanistan, Iraq, Pakistan, Somalia, and Turkey. Consanguinity has been suggested to account for part of this disparity. Since information on consanguinity is lacking, this suggestion is difficult to test. With an indirect approach, we addressed this question by comparing the risk of diseases with autosomal recessive inheritance in children born in Denmark of Danish-born women and of women born in these five countries, respectively.

METHODS

All children born in Denmark (1994-2010) were followed until 5 years of age or end-of-study period for the risk of hospitalisation with diseases of autosomal recessive aetiology, and therefore considered consanguinity-related. Diagnoses of autosomal recessive diseases were identified using two different methods: a literature review of consanguinity-associated diseases and a search in the Online Catalogue of Human Genes and Genetic Disorders. Risks were also calculated for diseases with known non-autosomal recessive aetiology (considered non-consanguinity-related). We estimated adjusted hazard ratios for the diseases in children of foreign-born women compared with children of Danish-born women.

RESULTS

Compared with offspring of Danish-born women, the risk of a consanguinity-related disease was significantly increased in children of foreign-born women, although the absolute risk was low. The risk of non-consanguinity-related diseases did not differ between the groups compared.

CONCLUSIONS

The findings support the hypothesis that consanguinity accounts for some, however a minor part, of the disparity in child mortality among migrants in Denmark.

Effect of consanguinity on birth defects in Saudi women: results from a nested case-control study

BACKGROUND

The role of consanguinity in the etiology of structural birth defects outside of chromosomal and inherited disorders has always been debated. We studied the independent role of consanguinity on birth defects in Saudi women with a high prevalence of consanguineous marriages.

METHODS

This case and control study was nested within a 3-year prospective cohort study to examine patterns of fetal and neonatal malformations in Saudi women at Prince Sultan Military Medical City (PSMMC), Riyadh -Saudi Arabia. Consanguineous marriages were defined as marriages with first or second cousins (related); unions beyond second cousins (distant relatives) were considered unrelated for this study.

RESULTS

During the 3-year study (July 2010 through June 2013), there were 28,646 total births; of these, we included 1,179 babies with major birth defects, and 1,262 babies as their controls. The consanguinity prevalence for all included women was 49.6%. The consanguinity among babies with major Birth Defects (BDs) was 54.5% and 45.2% for controls (P < 0.0002). The prevalence of major birth defects was 41.1 per 1000 total births. Univariate analysis showed that consanguinity had a statistically significant contribution in babies born with genetic syndromes, isolated renal defects, and isolated other defects (P < 0.05). Multivariate logistic regression analyses showed that consanguinity was an independent risk factor for this high prevalence of birth defects in the study population (P < 0.0002).

CONCLUSION

The prevalence of major birth defects in the study population is higher than what is reported from European countries. Consanguinity is a significant independent risk factor for the high prevalence of birth defects.

Risk factors for congenital anomaly in a multiethnic birth cohort: an analysis of the Born in Bradford study

BACKGROUND

Congenital anomalies are a leading cause of infant death and disability and their incidence varies between ethnic groups in the UK. Rates of infant death are highest in children of Pakistani origin, and congenital anomalies are the most common cause of death in children younger than 12 in this ethnic group. We investigated the incidence of congenital anomalies in a large multiethnic birth cohort to identify the causes of the excess of congenital anomalies in this community.

METHODS

We obtained questionnaire data from the mothers of children with one or more anomalies from the Born in Bradford study, a prospective birth cohort study of 13,776 babies and their families in which recruitment was undertaken between 2007 and 2011. Details of anomalies were prospectively reported to the study and we cross checked these details against medical records. We linked data for anomalies to maternal questionnaire and clinical data gathered as part of the Born in Bradford study. We calculated univariate and multivariate risk ratios (RRs) with 95% CIs for various maternal risk factors.

FINDINGS

Of 11,396 babies for whom questionnaire data were available, 386 (3%) had a congenital anomaly. Rates for congenital anomaly were 305·74 per 10,000 livebirths, compared with a national rate of 165·90 per 10,000. The risk was greater for mothers of Pakistani origin than for those of white British origin (univariate RR 1·96, 95% CI 1·56-2·46). Overall, 2013 (18%) babies were the offspring of first-cousin unions. These babies were mainly of Pakistani origin--1922 (37%) of 5127 babies of Pakistani origin had parents in first-cousin unions. Consanguinity was associated with a doubling of risk for congenital anomaly (multivariate RR 2·19, 95% CI 1·67-2·85); we noted no association with increasing deprivation. 31% of all anomalies in children of Pakistani origin could be attributed to consanguinity. We noted a similar increase in risk for mothers of white British origin older than 34 years (multivariate RR 1·83, 95% CI 1·14-3·00). Maternal education to degree level was protective (0·53, 95% CI 0·38-0·75), irrespective of ethnic origin.

INTERPRETATION

Consanguinity is a major risk factor for congenital anomaly. The risk remains even after adjustment for deprivation, and accounts for almost a third of anomalies in babies of Pakistani origin. High levels of educational attainment are associated with reduced risk in all ethnic groups. Our findings will be valuable in health promotion and public health, and to those commissioning antenatal, paediatric, and clinical genetic services. Sensitive advice about the risks should be provided to communities at increased risk, and to couples in consanguineous unions, to assist in reproductive decision making.

FUNDING

National Institute for Health Research Collaboration for Leadership in Applied Health Research and Care programme.

Prevalence of birth defects and risk-factor analysis from a population-based survey in Inner Mongolia, China

BACKGROUND

Birth Defects are a series of diseases that seriously affect children's health. Birth defects are generally caused by several interrelated factors. The aims of the article is to estimate the prevalence rate and types of birth defects in Inner Mongolia, China, to compare socio-demographic characteristics among the children with birth defects and to analyze the association between risk factors and birth defects.

METHODS

Data used in this study were obtained through baseline survey of Inner Mongolia Birth Defects Program, a population-based survey conducted from 2005 to 2008. The survey used cluster sampling method in all 12 administrative districts of Inner Mongolia. Sampling size is calculated according to local population size at a certain percentage. All live births, stillbirths and abortions born from October 2005 to September 2008, whose families lived in Inner Mongolia at least one year, were included. The cases of birth defects were diagnosed by the clinical doctors according to their experiences with further laboratory tests if needed. The inclusion criteria of the cases that had already dead were decided according to death records available at local cites. We calculated prevalence rate and 95% confidence intervals of different groups. Outcome variable was the occurrence of birth defects and associations between risk factors and birth defects were analyzed by using Poisson regression analysis.

RESULTS

976 children with birth defects were diagnosed. The prevalence rate of birth defects was 156.1 per 10000 births (95%CI: 146.3-165.8). The prevalence rate of neural tube defect (20.1 per 10000 births) including anencephaly(6.9 per 10000), spina bifida (10.6 per 10000), and encephalocele (2.7 per 10000) was the highest, followed by congenital heart disease (17.1 per 10000). The relative risk (RR) for maternal age less than 25 was 2.22 (95%CI: 2.05, 2.41). The RR of the ethnic Mongols was lower than Han Chinese (RR: 0.84; 95%CI: 0.80-0.89). The RR of the third and second pregnancy was significantly higher than the first pregnancy while a slight difference between the second and the first pregnancy was also found. Alcohol drinking of mothers, familial inheritance and living area were also found to be related to the occurrence of the birth defects.

CONCLUSIONS

Relatively higher birth defect rates were found in Inner Mongolia. This study found that maternal age less than 25, alcohol drinking, familiar inheritance, lower education level of mothers, times of pregnancies and living in rural areas may increase the risk of birth defects. Ethnic Mongols were less likely to have birth defects than Han Chinese.

Consanguinity, prematurity, birth weight and pregnancy loss: a prospective cohort study at four primary health center areas of Karnataka, India

OBJECTIVE

To determine whether consanguinity adversely influences pregnancy outcome in South India, where consanguinity is a common means of family property retention.

STUDY DESIGN

Data were collected from a prospective cohort of 647 consenting women, consecutively registered for antenatal care between 14 and 18 weeks gestation, in Belgaum district, Karnataka in 2005. Three-generation pedigree charts were drawn for consanguineous participants. χ (2)-Test and Student's t-test were used to assess categorical and continuous data, respectively, using SPSS version 14. Multivariate logistic regression adjusted for confounding variables.

RESULT

Overall, 24.1% of 601 women with singleton births and outcome data were consanguineous. Demographic characteristics between study groups were similar. Non-consanguineous couples had fewer stillbirths (2.6 vs 6.9% P=0.017; adjusted P=0.050), miscarriages (1.8 vs 4.1%, P=0.097; adjusted P=0.052) and lower incidence of birth weight <2500 g (21.8 vs 29.5%, P=0.071, adjusted P=0.044). Gestation <37 weeks was 6.2% in both the groups. Adjusted for consanguinity and other potential confounders, age <20 years was protective of stillbirth (P=0.01), pregnancy loss (P=0.023) and preterm birth (P=0.013), whereas smoking (P=0.015) and poverty (P=0.003) were associated with higher rates of low birth weight.

CONCLUSION

Consanguinity significantly increases pregnancy loss and birth weight <2500 g.

Relationship between consanguinity and depression in a south Indian population

A Pilot study was Carried out to study the association of consanguinity marriage with depression. It was observed that the consanguinity of marriage was associated with depression. The odds ratio was 5.66 (CI: 2.42-13.54). The age and sex had an association with depression. The age and sex adjusted odds ratio of consanguinity marriage was 7.66 (CI: 3.93-19.45) indicating that it is independently associated with depression.