OBJECTIVES: Congenital birth defects are the main source of disease burden among children under 5 years old in China. This study aims to compare the trends in disease burden of different congenital birth defects among Chinese children under 5 years old from 1990 to 2019, and to provide a scientific basis for strengthening the comprehensive prevention and control of birth defects. METHODS: Based on data from the Global Burden Disease (GBD) in 2019, the incidence mortality rate, and disability-adjusted life years (DALYs) rate of congenital birth defects among Chinese children under 5 years old from 1990 to 2019 were selected as evaluation indicators. The Joinpoint regression model was used to analyze the trends in disease burden of different types with congenital birth defects over three decades. The study also compared the differences in disease burden of congenital birth defects among children under 5 years old by gender. RESULTS: Compared to 1990, the DALYs rates of congenital heart anomalies (1 931.91/100 000), digestive congenital anomalies (364.63/100 000), neural tube defects (277.20/100 000), congenital musculoskeletal and limb anomalies (133.33/100 000), and Down syndrome (128.22/100 000) in children under 5 years old in China in 2019 were decreased 70.78%, 71.61%, 86.21%, 36.84% and 73.65%, respectively. From 1990 to 2019, the mortality rates and DALYs rates of different congenital birth defects showed an overall downward trend, but the incidence of digestive congenital anomalies and Down syndrome showed an upward trend after 2005 and 2001, respectively. Except for congenital musculoskeletal and limb anomalies, incidence of the remaining categories of birth defects were higher in boys than that in girls. CONCLUSIONS The disease burden of congenital birth defects in children under 5 years old in China is decreased substantially from 1990 to 2019, but the burden of congenital heart anomalies is still serious and the incidence of some birth defect diseases is on the rise, and it is still crucial to strengthen the prevention and treatment for birth defects in children and propose targeted measures according to their gender characteristics.
Child, Preschool ; Female ; Humans ; Male ; China/epidemiology* ; Cost of Illness ; Down Syndrome/epidemiology* ; East Asian People ; Congenital Abnormalities/epidemiology*

OBJECTIVETo investigate the distribution and characteristic of the karyotypes in Down syndrome (DS) patients in southern Hainan Province, China.

METHODSCytogenetic analysis was carried out in 132 cases clinically suspected of DS.

RESULTSEighty-six of the cases were diagnosed as DS with karyotype analysis. Among the DS patients in southern Hainan, 93.02% of the cases had typical trisomy 21, 3.49% had translocation, and 3.49% had mosaic karyotype. The percentage of DS babies born by younger mothers (<35 years) was greater than that of the babies born by elder mothers (91.86% vs 8.14%). In addition, a case of translocation between chromosomes 5 and 8 with regular trisomy 21 was identified, which represented the first case ever reported.

CONCLUSIONTypical trisomy 21 karyotype is more frequent in DS cases than translocation and mosaic karyotypes in southern Hainan Province, where the mother delivering a child with DS tends to be younger.

Abnormal Karyotype ; Child ; Child, Preschool ; China ; epidemiology ; Cytogenetics ; Down Syndrome ; epidemiology ; genetics ; Female ; Humans ; Infant ; Infant, Newborn ; Karyotyping ; Male

A cytogenetic study was performed on 4,117 Korean patients referred for suspected chromosomal abnormalities. Chromosome aberrations were identified in 17.5% of the referred cases. The most common autosomal abnormality was Down syndrome and Turner syndrome in abnormalities of sex chromosome. The proportions of different karyotypes in Down syndrome (trisomy 21 92.5%, translocation 5.1%, mosaic 2.4%) were similar to those reported in other countries. However, it was different in Turner syndrome (45, X 28.1%, mosaic 50.8%, 46, X, del (Xq) 4.4%, 46, X, i (Xq) 16.7%), in which proportions of mosaics and isochromosome, 46, X, i(Xq), were higher than those reported in other countries. In structural chromosome aberrations of autosome, translocation was the most common (43.6%), and duplication (21.3%), deletion (14.4%), marker chromosome (7.9%) and ring chromosome (4.0%) followed in order of frequency. Rates of several normal variant karyotypes were also described. Inversion of chromosome 9 was observed in 1.7% of total referred cases.
Adolescence ; Chromosomes, Human, Pair 6 ; Down Syndrome/genetics* ; Down Syndrome/epidemiology* ; Family Health ; Female ; Gene Deletion ; Human ; Infant, Newborn ; Inversion (Genetics) ; Karyotyping ; Klinefelter's Syndrome/genetics ; Klinefelter's Syndrome/epidemiology ; Korea/epidemiology ; Male ; Mosaicism ; Prevalence ; Translocation (Genetics) ; Turner's Syndrome/genetics* ; Turner's Syndrome/epidemiology* ; X Chromosome ; Y Chromosome

PURPOSE: Increased maternal age is a major risk factor for chromosomal abnormalities. The maternal age-specific risk of fetal trisomy was theoretically calculated. We investigated the actual frequency of fetal trisomy between 16 and 24 gestational weeks in pregnant women over the age of 34 at delivery. MATERIALS AND METHODS: We retrospectively, over a four-year period, reviewed the medical records of women with singleton pregnancies that started their antenatal care before the 10th week of pregnancy. Pregnant women aged 34 to 45 years at the time of delivery were enrolled and divided into groups of one-year intervals. We investigated the frequency of Down syndrome and all trisomies as a function of the maternal age and compared with the theoretical maternal-age-specific risk. RESULTS: Of the 5,858 pregnant women enrolled in the study, the rate of trisomy 21 was 0.29% (17 cases). The observed frequencies of trisomy 21 in women with maternal ages of 35 years and 40 years were 1:1,116 and 1:141, respectively. The rate of all trisomies was 0.39% (23 cases). The observed frequencies of all trisomies in women with maternal ages of 35 years and 40 years were 1:372 and 1:56, respectively. CONCLUSION: The frequencies of Down syndrome and all trisomies were proportional to the maternal age. However, the observed frequencies of Down syndrome and all trisomies between the 16 and 24 gestational weeks were lower than the theoretical rates.
Chromosome Aberrations ; Down Syndrome ; Epidemiology ; Female ; Humans ; Maternal Age ; Medical Records ; Pregnancy ; Pregnant Women* ; Retrospective Studies ; Risk Factors ; Trisomy*

BACKGROUNDTo establish the prevalence of hearing deficit in children with Down syndrome (DS) in Hong Kong as measured by brainstem auditory evoked potentials (BAEP). The secondary objective is to examine the agreement between BAEP and clinical questioning in detecting hearing deficit in DS.

METHODSConsecutive DS patients attending the Down's Clinic in a regional pediatric referral center were recruited into this cross-sectional study. BAEP data performed within 12 months were retrieved. The care-taker was interviewed with a structured questionnaire to detect any symptom of hearing impairment. BAEP findings and clinical questionings were compared in an agreement analysis using quadratic weighted kappa statistics.

RESULTSFifty DS patients (35 male, 15 female, mean age 11.70 years ± 5.74 standard deviation) were recruited. Eighteen patients (36.0%) were identified having hearing deficit by BAEP. Among patients with hearing impairment, 13 patients (72.2%) had a conductive deficit, and most have mild to moderate hearing loss. Five patients (27.8%) had sensorineural deficit and most have moderate to severe degree. Eight (44.4%) had bilateral hearing deficit. Care-takers of 13 patients (26.0%) reported symptoms of hearing impairment, with 9 (69.2%) having mild symptoms, 3 (23.1%) had moderate symptoms and 1 (7.7%) had severe symptoms. The weighted kappa was 0.045 (95.0% confidence interval - 0.138-0.229), indicating very poor strength of agreement between BAEP and clinical questioning. For patients with conductive hearing impairment, only 1 patients (7.7%) recalled history of otitis media.

CONCLUSIONSThe estimated point prevalence of hearing impairment in Chinese DS children in Hong Kong is 36%. Our finding of poor strength of agreement between objective testing and symptom questioning reflects significant underestimation of hearing impairment by history taking alone. In view of the high prevalence and low parental awareness, continuous surveillance of hearing is mandatory for DS patients throughout childhood and adolescence.

Adolescent ; Child ; Cross-Sectional Studies ; Down Syndrome ; epidemiology ; physiopathology ; Evoked Potentials, Auditory ; physiology ; Female ; Hearing Loss ; epidemiology ; etiology ; Humans ; Male ; Prevalence

OBJECTIVETo develop a method for evaluating the feasibility of prenatal screening using local median value and determining the cut-off value.

METHODSWith receiver operating characteristic curve (ROC) analysis, results of second trimester prenatal screening calculated by a local median value in a new model and the built-in median value in 2T software were compared. The cut-off value was set by serial analysis of true and false positive rates and other relevant data.

RESULTSThe ROC curve has accurately estimated the difference in the screening efficacy between a local median value and that embedded in the 2T model, and established a reasonable cut-off value for the laboratory based on false positive rate and detection rate.

CONCLUSIONThe method of ROC curve can be used to evaluate the performance of local median value in prenatal screening and to test the rationality of cut-off value established in the laboratory. As the result, a better cut-off value may be derived.

China ; epidemiology ; Down Syndrome ; diagnosis ; epidemiology ; genetics ; Female ; Humans ; Male ; Pregnancy ; Pregnancy Trimester, Second ; genetics ; Prenatal Diagnosis ; instrumentation ; methods ; standards ; ROC Curve ; Software

PURPOSE: The aims of this study were to examine the distribution of refractive errors and clinical characteristics of strabismus in Korean patients with Down's syndrome. METHODS: A total of 41 Korean patients with Down's syndrome were screened for strabismus and refractive errors in 2009. RESULTS: A total of 41 patients with an average age of 11.9 years (range, 2 to 36 years) were screened. Eighteen patients (43.9%) had strabismus. Ten (23.4%) of 18 patients exhibited esotropia and the others had intermittent exotropia. The most frequently detected type of esotropia was acquired non-accommodative esotropia, and that of exotropia was the basic type. Fifteen patients (36.6%) had hypermetropia and 20 (48.8%) had myopia. The patients with esotropia had refractive errors of +4.89 diopters (D, +/-3.73) and the patients with exotropia had refractive errors of -0.31 D (+/-1.78). Six of ten patients with esotropia had an accommodation weakness. Twenty one patients (63.4%) had astigmatism. Eleven (28.6%) of 21 patients had anisometropia and six (14.6%) of those had clinically significant anisometropia. CONCLUSIONS: In Korean patients with Down's syndrome, esotropia was more common than exotropia and hypermetropia more common than myopia. Especially, Down's syndrome patients with esotropia generally exhibit clinically significant hyperopic errors (>+3.00 D) and evidence of under-accommodation. Thus, hypermetropia and accommodation weakness could be possible factors in esotropia when it occurs in Down's syndrome patients. Based on the results of this study, eye examinations of Down's syndrome patients should routinely include a measure of accommodation at near distances, and bifocals should be considered for those with evidence of under-accommodation.
Adolescent ; Adult ; Child ; Child, Preschool ; Down Syndrome/*complications/epidemiology ; Female ; Humans ; Incidence ; Male ; Prevalence ; Refractive Errors/complications/*epidemiology ; Republic of Korea/epidemiology ; Retrospective Studies ; Strabismus/complications/*epidemiology ; *Vision Screening ; Young Adult

OBJECTIVES: To investigate the accuracy and scientific validity of the current very low risk factor for hereditary diseases in humans following exposures to ionizing radiation adopted by the United Nations Scientific Committee on the Effects of Atomic Radiation and the International Commission on Radiological Protection. The value is based on experiments on mice due to reportedly absent effects in the Japanese atomic bomb (Abomb) survivors. METHODS: To review the published evidence for heritable effects after ionising radiation exposures particularly, but not restricted to, populations exposed to contamination from the Chernobyl accident and from atmospheric nuclear test fallout. To make a compilation of findings about early deaths, congenital malformations, Down’s syndrome, cancer and other genetic effects observed in humans after the exposure of the parents. To also examine more closely the evidence from the Japanese A-bomb epidemiology and discuss its scientific validity. RESULTS: Nearly all types of hereditary defects were found at doses as low as one to 10 mSv. We discuss the clash between the current risk model and these observations on the basis of biological mechanism and assumptions about linear relationships between dose and effect in neonatal and foetal epidemiology. The evidence supports a dose response relationship which is non-linear and is either biphasic or supralinear (hogs-back) and largely either saturates or falls above 10 mSv. CONCLUSIONS: We conclude that the current risk model for heritable effects of radiation is unsafe. The dose response relationship is non-linear with the greatest effects at the lowest doses. Using Chernobyl data we derive an excess relative risk for all malformations of 1.0 per 10 mSv cumulative dose. The safety of the Japanese A-bomb epidemiology is argued to be both scientifically and philosophically questionable owing to errors in the choice of control groups, omission of internal exposure effects and assumptions about linear dose response.
Accidental Falls ; Animals ; Asian Continental Ancestry Group ; Down Syndrome ; Epidemiology ; Genetic Diseases, Inborn ; Humans ; Mice ; Nuclear Weapons ; Parents ; Radiation, Ionizing ; Risk Factors ; Survivors ; United Nations

PURPOSE: Gall bladder (GB) stones in children are rarely observed, and so reports of them have been quite limited in Korea. Therefore, we tried to assess the epidemiology and clinical features of children with GB stone diagnosed at Severance Hospital. METHODS: A clinical study was performed on 18 patients below 15 years of age diagnosed with GB stone by abdominal ultrasonography or CT scan at Severance hospital from January 1999 to May 2005. RESULTS: Concerning patients' profile, their sex ratio of male to female in total 18 cases was 2:1 with the mean age of 6+/-4.3 years. 15 patients (83.3%) were asymptomatic. Inducing factors were found in 14 children (77.8%) including ceftriaxone therapy in 6 cases (33.3%), infection in 4 cases (22.2%), spherocytosis in 3 cases (16.7%), Down syndrome and abdominal operation in 1 case (5.6%) respectively. Single stone was found in 13 cases (76.5%) and multiple in 4 cases (23.5%). 15 cases (88.2%) had the stones less than 5 mm in size, and 2 cases (11.8%) between 5 and 10 mm. 17 patients received conservative treatment, and one patient had cholecystectomy due to Meckel diverticulum. CONCLUSION: In this report, Pediatric GB stones are predominant in male children, without typical symptoms, having inducing factors, single and small. Recently the diagnosis of them has been increased because of the development of imaging study. But the reports for them were still rare in Korea. Therefore the study for them is more necessary to find it's clinical characteristics.
Ceftriaxone ; Child* ; Cholecystectomy ; Diagnosis ; Down Syndrome ; Epidemiology ; Female ; Humans ; Korea ; Male ; Meckel Diverticulum ; Sex Ratio ; Tomography, X-Ray Computed ; Ultrasonography ; Urinary Bladder Calculi* ; Urinary Bladder*

INTRODUCTIONInfants with Down syndrome (DS) are at higher risk of hearing loss (HL). Normal hearing at one year of age plays an important part in language development. An audit was conducted to determine the impact of the newborn hearing screening program on the incidence, type and timing of diagnosis of HL during first year of life.

MATERIALS AND METHODSInfants with DS were scheduled for Universal Newborn Hearing Screening (UNHS) within 4 weeks of life. If they passed, they had a high-risk screen at 3 to 6 months. They were referred to the otolaryngology department if they did not pass the UNHS or the high-risk screen. Information was obtained from the computerised data tracking system and case notes. Infants born from April 2002 to January 2005 and referred to the DS clinic of our hospital were analysed.

RESULTSThirty-seven (82.2%) of 45 infants underwent UNHS, of which 12 (32.4%) infants did not pass. Of remaining 33 infants, 27 had high-risk screen done of which 14 (51.8%) did not pass. Twenty-eight infants were referred to the ear, nose, throat (ENT) clinic: 12 from UNHS, 14 from high-risk screens and 2 from the DS clinic. Eleven (39.2%) defaulted follow-up. Fourteen (82.3%) of 17 infants who attended the ENT Clinic had HL. Twelve (85.7%) were conductive, and 2 (14.2%) mixed. Nine (64.2%) had mild-moderate HL and 3 (21%) had severe HL. The mean age of diagnosis was 6.6 ± 3.3 months. All were treated medically, plus surgically if indicated. By 12 months of age, the hearing had normalised in 4 (28.6%) infants and remained the same in 3 (21.4%). Five (35.7%) defaulted follow-up. Thirty-five out of 45 (77.8%) underwent complete hearing screen in the first year of life (UNHS & High-risk screen). Six out of 45 (13.3%) had incomplete screening. Fourteen out of 41 (34.1%) had HL of varying degrees. Four out of 45 (8.8%) did not have any audiological assessment in first year of life.

CONCLUSIONThe incidence of HL in the first year of life was high (34.1%). Eighty-five percent were conductive with 64.2% in mild-moderate range. One third of infants hearing normalized after treatment, one third remained unaltered and one third of infants did not attend follow-up. An aggressive approach involving early screening after birth and continued surveillance and early referral to appropriate agencies are essential for establishing timely diagnosis and treatment. Measures to reduce the high default rate during long-term follow-up are needed. Parent education and integrated multidisciplinary follow-up clinic may be useful.

Down Syndrome ; complications ; Early Diagnosis ; Female ; Hearing Loss ; diagnosis ; epidemiology ; etiology ; physiopathology ; Hearing Tests ; Humans ; Infant ; Male ; Mass Screening ; Medical Audit ; Population Surveillance ; methods ; Severity of Illness Index ; Singapore ; epidemiology ; Trisomy ; genetics