Epidemiological characterization of clubfoot: a population-based study of a surveillance program in Colombia

Clubfoot is a common musculoskeletal congenital abnormality, with a prevalence of 5-20 cases per 10 000 live births in low to middle-income countries. If left untreated, clubfoot causes severe consequences for the child: gait disturbances, reduced quality of life, and limited work opportunities. Our objective was to characterize clubfoot and determine its prevalence and associated risk factors in Bogotá and Cali, Colombia, from 2002 to 2020. A retrospective case-control study design was employed, analyzing data from birth defect reports provided by the Program for the Prevention and Follow-up of Congenital Defects and Orphan Diseases surveillance system. Cases included live births or stillbirths with clubfoot, while controls consisted of infants without congenital abnormalities, matched in terms of birth date and hospital. Prevalence was calculated considering a 95% confidence interval using Poisson distribution, and risk factors were assessed through adjusted odds ratios obtained by logistic regression model. Of 558 255 births, 861 cases of clubfoot were identified, 48.20% were postural clubfoot, and 15 cases were syndromic clubfoot. In Bogota, prevalence rate was 15.1 per 10 000 live births, whereas in Cali it was 17.29 per 10 000 live births. Family history of clubfoot within first-degree relatives was identified as a risk factor for clubfoot. Investigating risk factors for clubfoot holds significant importance in terms of preventing and reducing morbidity within this population. Helping to drive government and healthcare initiatives aimed at providing timely and effective treatment.

A case-control study characterizing polydactyly risk factors in Bogotá and Cali, Colombia between 2002 and 2020

BACKGROUND

Polydactyly is a congenital abnormality characterized by the presence of additional fingers on one or more extremities. In Colombia, polydactyly accounted for 17% of musculoskeletal congenital abnormalities in 2021, with a prevalence of 6.03 per 10,000 live births. The purpose of this study was to determine the prevalence of polydactyly and identify associated risk factors in Bogotá and Cali, Colombia, from 2002 to 2020.

METHODS

A retrospective case-control study design was employed, analyzing data from birth defect reports provided by the Program for the Prevention and Follow-up of Congenital Defects and Orphan Diseases surveillance system. Cases included live births or stillbirths with polydactyly, while controls consisted of infants without congenital abnormality, matched in terms of birth date and hospital. Prevalence of polydactyly was calculated and risk factors were assessed through odds ratios obtained by logistic regression models, considering a 95% confidence interval.

RESULTS

Among the 558,255 births included in the study, 848 cases of polydactyly were identified, resulting in a prevalence rate of 15.19 per 10,000 live births. Risk factors associated with polydactyly included male newborn sex, pregestational diabetes, and a family history of malformation among first-degree relatives.

CONCLUSION

These findings highlight the importance a surveillance system aimed to characterize populations with congenital abnormalities, providing a better option for analyzing risk factors, help improving prevention, diagnosis, notification, and optimal treatment in patients.

Risk factors characterisation for CHD: a case-control study in Bogota and Cali, Colombia, 2002-2020

OBJECTIVE

CHDs correspond to 28% of all congenital anomalies, being the leading cause of infant mortality in the first year of life. Thus, it is essential to explore risk factors for CHDs presentation, allowing the detection of probable cases within a population.

METHODS

We identified newborns with CHDs within a cohort from the Program for the Prevention and Monitoring of Congenital Defects in Bogota and Cali, 2002-2020. Cases were classified as isolated, complex isolated, polymalformed, and syndromic. Variables were analysed by comparing case and control averages with Student's t test using a 95% confidence level.

RESULTS

Prevalence obtained was 19.36 per 10 000 live births; non-specified CHD, ventricular septal defect, and atrial septal defect were the most prevalent. As risk factors were found: paternal and maternal age above 45 years, pregestational diabetes, mother's body mass index above 25, low educational level, and socio-economic status. As protective factors: folic acid consumption within the first trimester and pregestational period.

CONCLUSION

Different risk and protective factors associated with the presentation of CHDs have been described. We consider that public health strategies should be aimed to reduce risk factors exposure. Also, improving diagnosis and prognosis by having a close monitoring on high-risk patients.

Paternal age and risk for selected birth defects in a large South American sample

BACKGROUND

The relationship between maternal age (MA) and birth defects (BD) has been extensively studied while much less research, mostly with discordant results, has focused on the risk of paternal age (PA) for BD. Furthermore, no consensus has been reached on the best way to control the association of PA with MA.

OBJECTIVES

The aim of the study was to evaluate the risk of PA increase, at 1-year intervals, for selected BD, especially controlling for the confounding effect of MA.

METHODS

The sample comprised of 27,944 liveborns presenting 1 of 18 selected isolated BD. Conditional logistic regressions were applied to evaluate the risk of advanced PA and its yearly increase, adjusting by MA and other variables.

RESULTS

Of the 18 analyzed BD, only the risk for preaxial polydactyly (PreP) showed a significant association with increasing PA, while advanced MA was of low risk. For esophageal and anal atresia, associations with both PA and MA increases were observed.

CONCLUSIONS

Results support the hypothesis of advanced PA as a risk factor for PreP and helps clarify the so far unexplained nonrandom association between this defect and Down syndrome.

Association between Genitourinary and Congenital Heart Defects: A 52-year Case-Control Study of the Latin American Collaborative Study of Congenital Malformations (ECLAMC)

Background Congenital urological anomalies are present in 4.3/10 thousand newborns, and their association with other anomalies may increase the overall mortality and disability. The present study establishes the risk of having congenital urological anomalies presenting associated cardiopathies.

Methods We conducted a retrospective case-control study using the Latin American Collaborative Study of Congenital Malformations (Estudio Colaborativo Latino Americano de Malformaciones Congénitas, ECLAMC, in Spanish). The analysis included all registered cases of congenital urological malformation from 1967 to 2019. Patients with or without associated heart defects were included for the statistical analysis. Odds ratios (ORs) were calculated using a 95% confidence interval (95% CI). We compared the variables with the Chi-squared test and analysis of variance (ANOVA). The statistical analysis was performed using the Statistical Package for the Social Sciences (IBM SPSS Statistics for Windows, IBM Corp., Armonk, NY, United States) software, version 27.0. Values of p < 0.05 were considered statistically significant.

Results A total of 7,767,161 newborns were evaluated, and 17,834 genital and upper urinary tract malformations were identified. Of these, 64.2% were genital anomalies, and 35.8% were abnormalities of the upper urinary tract. Genitourinary malformations and concomitant congenital heart defects (GU + C) were observed in 3.5% of the cases. Subjects with GU + C had a higher number of malformations (4.59 ± 2.3) than patients without heart defects (1.53 ± 1.58) (p < 0.000). The OR was of 3.61 (range: 1.86–7.00) for cloacal exstrophy, of 4.01 (range: 3.14–5.12) for imperforate anus, of 5.52 (range: 3.92–7.78) for horseshoe kidney, and of 13.7 (range: 6.65–28.22) for trisomy 21 (Down syndrome) with malformations of the upper urinary tract.

Conclusion The association of congenital heart defects with urological anomalies is higher for complex congenital anomalies such as imperforate anus, cloacal exstrophy, and horseshoe kidney. Patients with urological abnormalities and Down syndrome have the highest likelihood.

Neonatal anthropometry of malformed newborns: A large South American population-based study

BACKGROUND

Population-based anthropometric evaluation of malformed newborns is scarce.

OBJECTIVES

To evaluate malformed newborns' foetal growth using the ICD 10 malformations' classification.

METHODS

A study including 33,769 newborns (14,857 malformed and 18,912 nonmalformed), selected from 678,840 births from nine South American countries, period 2010-2018, was conducted. Prevalence of severe small and small for gestational age was calculated for malformed and nonmalformed newborns classified by preterm birth categories. Prevalence and relative risk (RR) with its 95% confidence interval (CI) were calculated. The associations between anthropometric phenotypes and congenital malformations were evaluated with generalized linear models.

RESULTS

Prevalence of preterm and term severe small and small for gestational age newborns was higher in malformed than that in nonmalformed neonates. For grouped ICD 10 malformations categories, the RR for severe small for gestational age was 2.88 (95% CI 2.51, 3.30) and 2.10 (95% CI 1.92, 2.30) for small for gestational age. For at-term and preterm malformed newborns, the RR for severe small for gestational age was 2.21 (95% CI 1.87, 2.61) and 3.21 (95% CI 2.52, 4.10), respectively; for small for gestational age, the RR was 2.31 (95% CI 2.11, 2.53) for at-term newborns and 2.58 (95% CI 2.16, 3.08) for preterm ones.

CONCLUSIONS

Prevalence and relative risk of severe small and small for gestational age vary according to the group of malformations and gestational age; they increase in congenital malformations of the nervous, respiratory and digestive systems, and in chromosomal abnormalities and are lower for malformations of eye, ear, face and neck and cleft lip and palate. Foetal growth considered together with malformed newborns' gestational age would allow for inferring different risks of morbidity and mortality.

Description and results of birth defects surveillance and follow-up programs in Bogotá and Cali, Colombia, 2002-2019

Birth defects are structural or functional defects present at birth and are caused by different factors that affect intrauterine development. They are the second most common cause of death under five years of age in Latin America and the Caribbean. In Bogotá and Cali, Colombia, there are two surveillance programs established to evaluate the prevalence of them. The purpose of the following article is to describe the experience and results of the surveillance of the Birth Defects Surveillance Programs in Bogotá and Cali, Colombia, 2002-2019. The information was taken from the surveillance programs that have an active hospital system in some institutions of the city (ECLAMC modality), and use data from the passive national system (Sistema Nacional de Vigilancia en Salud Pública - SIVIGILA) to expand their coverage. From 2002 until 2019, 1,289.650 births have been monitored through one of the surveillance programs, including both methodologies. The importance of surveillance programs relies on the amount of data obtained that allows the development of research, the detection of potential changes throughout time, and the guidance of public policies to improve promotion and prevention strategies.

The Latin American network for congenital malformation surveillance: ReLAMC

The early detection of congenital anomaly epidemics occurs when comparing current with previous frequencies in the same population. The success of epidemiologic surveillance depends on numerous factors, including the accuracy of the rates available in the base period, wide population coverage, and short periodicity of analysis. This study aims to describe the Latin American network of congenital malformation surveillance: ReLAMC, created to increase epidemiologic surveillance in Latin America. We describe the main steps, tasks, strategies used, and preliminary results. From 2017 to 2019, five national registries (Argentina [RENAC], Brazil [SINASC/SIM-BRS], Chile [RENACH], Costa Rica [CREC], Paraguay [RENADECOPY-PNPDC]), six regional registries (Bogotá [PVSDC-Bogota], Cali [PVSDC-Cali], Maule [RRMC SSM], Nicaragua [SVDC], Nuevo-León [ReDeCon HU], São Paulo [SINASC/SIM-MSP]) and the ECLAMC hospital network sent data to ReLAMC on a total population of 9,152,674 births, with a total of 101,749 malformed newborns (1.1%; 95% CI 1.10-1.12). Of the 9,000,651 births in countries covering both live and stillbirths, 88,881 were stillborn (0.99%; 95% CI 0.98-0.99), and among stillborns, 6,755 were malformed (7.61%; 95% CI 7.44-7.79). The microcephaly rate was 2.45 per 10,000 births (95% CI 2.35-2.55), hydrocephaly 3.03 (2.92-3.14), spina bifida 2.89 (2.78-3.00), congenital heart defects 15.53 (15.27-15.79), cleft lip 2.02 (1.93-2.11), cleft palate and lip 2.77 (2.66-2.88), talipes 2.56 (2.46-2.67), conjoined twins 0.16 (0.14-0.19), and Down syndrome 5.33 (5.18-5.48). Each congenital anomaly showed heterogeneity in prevalence rates among registries. The harmonization of data in relation to operational differences between registries is the next step in developing the common ReLAMC database.

Digital Pattern Recognition for the Identification and Classification of Hypospadias Using Artificial Intelligence vs Experienced Pediatric Urologist

OBJECTIVE

To improve hypospadias classification system, we hereby, show the use of machine learning/image recognition to increase objectivity of hypospadias recognition and classification. Hypospadias anatomical variables such as meatal location, quality of urethral plate, glans size, and ventral curvature have been identified as predictors for postoperative outcomes but there is still significant subjectivity between evaluators.

MATERIALS AND METHODS

A hypospadias image database with 1169 anonymized images (837 distal and 332 proximal) was used. Images were standardized (ventral aspect of the penis including the glans, shaft, and scrotum) and classified into distal or proximal and uploaded for training with TensorFlow. Data from the training were outputted to TensorBoard, to assess for the loss function. The model was then run on a set of 29 "Test" images randomly selected. Same set of images were distributed among expert clinicians in pediatric urology. Inter- and intrarater analyses were performed using Fleiss Kappa statistical analysis using the same 29 images shown to the algorithm.

RESULTS

After training with 627 images, detection accuracy was 60%. With1169 images, accuracy increased to 90%. Inter-rater analysis among expert pediatric urologists was k= 0.86 and intrarater 0.74. Image recognition model emulates the almost perfect inter-rater agreement between experts.

CONCLUSION

Our model emulates expert human classification of patients with distal/proximal hypospadias. Future applicability will be on standardizing the use of these technologies and their clinical applicability. The ability of using variables different than only anatomical will feed deep learning algorithms and possibly better assessments and predictions for surgical outcomes.

Anomalias congênitas na perspectiva da vigilância em saúde: compilação de uma lista com base na CID-10

Resumo Objetivo: Propor uma lista de anomalias congênitas com códigos correspondentes na Classificação Estatística Internacional de Doenças e Problemas Relacionados à Saúde – 10ᵃ Revisão (CID-10), visando a aplicação no âmbito da vigilância em saúde. Métodos: Em dezembro de 2019, realizou-se busca nas seguintes fontes de dados: CID-10; CID-11; anomalias monitoradas por três modelos de vigilância; base de informações sobre doenças raras (Orphanet). Realizou-se extração das anomalias a partir dessas fontes, processamento para correspondência com base na CID-10 e compilação mediante revisão manual. Resultados: Foram identificados 898 códigos, dos quais 619 (68,9%) constavam no capítulo XVII da CID-10. Dos 279 códigos de outros capítulos, 19 foram exclusivos da busca na CID-11, 72 dos modelos de vigilância, 79 da Orphanet e 36 da busca de termos na CID-10. Conclusão: Os códigos que constam do capítulo XVII da CID-10 não captam a totalidade das anomalias congênitas, indicando a necessidade de adoção de uma lista ampliada.

Geography of Microcephaly in the Zika Era: A Study of Newborn Distribution and Socio-environmental Indicators in Recife, Brazil, 2015-2016

OBJECTIVES

We assessed sociodemographic and health care factors of mothers and newborns during a 2015-2016 outbreak of microcephaly in Recife, Brazil, and we analyzed the spatial distribution and incidence risk of newborns with microcephaly in relation to socio-environmental indicators.

METHODS

We collected data from August 2015 through May 2016 from Brazil's Live Birth Information System and Bulletin of Microcephaly Notification, and we geocoded the data by maternal residence. We constructed thematic maps of districts, according to socio-environmental and vector indicators. We identified spatial aggregates of newborns with microcephaly by using the Bernoulli model. We performed logistic regression analyses to compare the incidence risk of microcephaly within socio-environmental indicator groups.

RESULTS

We geocoded 17 990 of 19 554 (92.0%) live births in Recife, of which 202 (1.1%) newborns were classified as having microcephaly, based on a head circumference of ≥2 standard deviations below the mean. Larger proportions of newborns with microcephaly (compared with newborns without microcephaly) were born to mothers who delivered in a public hospital, did not attend college, were aged ≤19, or were black or mixed race. A higher risk of microcephaly (incidence rate ratio [IRR] = 3.90; 95% confidence interval [CI], 1.88-8.06) occurred in districts with the lowest (vs highest) Municipal Human Development Index (ie, an index that assesses longevity, education, and income). The risk of microcephaly was significantly higher where rates of larvae density (IRR = 2.31; 95% CI, 1.19-4.50) and larvae detection (IRR = 2.04; 95% CI, 1.05-4.00) were higher and rates of sewage system (IRR = 2.20; 95% CI, 1.16-4.18) and garbage collection (IRR = 1.96; 95% CI, 0.99-3.88) were lower. Newborns with microcephaly lived predominantly in the poorest areas and in a high-risk cluster (relative risk = 1.89, P = .01) in the north.

CONCLUSIONS

The disproportionate incidence of microcephaly in newborns in poor areas of Recife reinforces the need for government and public health authorities to formulate policies that promote social equity and support for families and their children with microcephaly.

Neural tube defects: Sex ratio changes after fortification with folic acid

Background

Historically, neural tube defects (NTDs) have predominated in female infants but the reasons remain unclear. In South America, the pre- folic acid fortification (FAF) rates of NTDs were around 18/10,000 births for females and 12/10,000 births for males, with an estimated sex ratio (male/female) of 0.67. During the post- FAF period, unpublished routine reports have indicated changes in the sex ratio for these defects while some descriptive reports are controversial. To date and to our knowledge, however, no studies specifically focusing on these changes to test this hypothesis directly have been undertaken. The aim of this study was to analyze changes in the sex ratio of infants with NTDs after FAF in South American countries.

Materials and methods

With a descriptive cross-sectional study design, 2,597 infants with isolated NTDs born between 1990 and 2013 in 3 countries participating in the Latin American Collaborative Study of Congenital Malformations (ECLAMC) network were included: (Chile N = 521 and Argentina N = 1,619 [with FAF policies]; Venezuela N = 457 [without FAF policies; used as control]; total births = 2,229,561). The differences-in-differences method and Poisson regressions were used to evaluate the sex ratio shift from female to male before vs. after FAF, and to assess whether these differences were related to the fortification.

Results and conclusions

In Chile and Argentina the prevalence of NTDs, particularly anencephaly and cervico-thoracic spina bifida, showed a greater reduction rate in females than in males after FAF, resulting in a change of the sex ratio of infants with NTDs. Some mechanisms possibly involved in this differential reduction are proposed which might be useful to identify the pathogenesis of NTDs as a whole and specifically of those susceptible to the protective effect of folic acid.

Risk factors for congenital diaphragmatic hernia in the Bogota birth defects surveillance and follow-up program, Colombia

PURPOSE

The mortality rate for congenital diaphragmatic hernia (CDH) remains high and prevention efforts are limited by the lack of known risk factors. The aim of this study was to determine prevalence, risk factors, and neonatal results associated with CDH on a surveillance system hospital-based in Bogotá, Colombia.

METHODS

The data used in this study were obtained from The Bogota Birth Defects Surveillance and Follow-up Program (BBDSFP), between January 2001 and December 2013. With 386,419 births, there were 81 cases of CDH. A case-control methodology was conducted with 48 of the total cases of CDH and 192 controls for association analysis.

RESULTS

The prevalence of CDH was 2.1 per 10,000 births. In the case-control analysis, risk factors found were maternal age ≥35 years (OR, 33.53; 95 % CI, 7.02-160.11), infants with CDH were more likely to be born before 37 weeks of gestation (OR, 5.57; 95 % CI, 2.05-15.14), to weigh less than 2500 g at birth (OR, 9.05; 95 % CI, 3.51-23.32), and be small for gestational age (OR, 5.72; 95 % CI, 2.18-14.99) with a high rate of death before hospital discharge in the CDH population (CDH: 38 % vs BBDSFP: <1 %; p < 0.001).

CONCLUSIONS

The prevalence of CDH calculated was similar to the one reported in the literature. CDH is strongly associated with a high rate of death before hospital discharge and the risk factors found were maternal age ≥35 years, preterm birth, be small for gestational age, and have low weight at birth. These neonatal characteristics in developing countries would help to identify early CDH. Prevention efforts have been limited by the lack of known risk factors and established epidemiological profiles, especially in developing countries.

Descriptive analysis of high birth prevalence rate geographical clusters of congenital anomalies in South America

BACKGROUND

The birth prevalence rate (BPR) of congenital anomalies (CAs) is heterogeneous and exhibits geographical and sociocultural variations throughout the world. In South America (SA), high birth prevalence regions of congenital anomalies have been observed. The aim of this study was to identify, describe, and characterize geographical clusters of congenital anomalies in SA.

METHODS

This observational descriptive study is based on clinical epidemiological data registered by the Latin-American Collaborative Study of Congenital Malformations network. Between 1995 and 2012, a total of 25,082 malformed newborns were ascertained from 2,557,424 births at 129 hospitals in SA. The spatial scan statistic was used to determine geographical regions with high BPR of CAs. The BPR was obtained with a Poisson regression model. Odds ratios were estimated for several risk factors inside the geographical clusters.

RESULTS

We confirmed the existence of high BPR regions of CAs in SA. Indicators of low socioeconomic conditions, such as a low maternal education, extreme age childbearing, infectious diseases, and medicine use during pregnancy were detected as risk factors inside these regions. Native and African ancestries with high frequency of consanguineous marriages could explain partially these high BPR clusters.

CONCLUSION

The recognition of clusters could be a starting point in the identification of susceptibility genes associated with the occurrence of CA in high BPR regions.

Congenital Malformations and Consequential Epidemiology

A call for a shift in the discipline of epidemiology, away from those aimed at identifying risk factors and toward those aimed at more directly improving health - so called consequential epidemiology. This call for epidemiologists to engage in solving the biggest public health problems has been heralded for decades by Cates and more recently by Galea [Am J Epidemiol 2013; 178; 1185-94]. In consideration of the consequential epidemiology perspective, the impacts of epidemiologic research of birth defects over the recent decades are evaluated and directions for the field are proposed. While many causal factors have been identified, the causes of the majority of birth defects remain unknown. Folic acid intake notwithstanding, primary prevention of birth defects is elusive. Meanwhile, research that identifies what improves the lives of individuals born with a birth defect and how to ensure those factors are available to all affected would have great impact. In summary, a consequentialist approach to birth defects epidemiology requires a shift in research agendas and teams, but the opportunities are wide open.