Descriptive epidemiology of Down’s syndrome in Estonia

Abstract

The aim of the study was to investigate the livebirth prevalence of Down's syndrome (DS) in Estonia during the past 14 years, create a DS database and observe the effectiveness of prenatal screening. This is a population-based descriptive study. The study subjects were children with DS diagnosis born between the years 1990 and 2003. We collected data from genetic centres in Estonia, from the databases of DS support groups, from institutions for disabled children and from the registers of family doctors/paediatricians. Prenatal screening for chromosomal anomalies for women aged >or=35 years was started in Estonia in 1995. Therefore, we divided the DS children into two groups: 112 born between 1990 and 1994 comprise group I, and 127 born between 1995 and 2003 comprise group II. Group II was further divided into two subgroups: IIa, from 1995 to 1998, when screening of advanced maternal age (>or=35 years) commenced, and IIb, from 1999 to 2003, when screening of second trimester maternal serum for younger women commenced. Prenatally, 68 cases of DS were diagnosed between 1995 and 2003 in the whole of Estonia, and all of these pregnancies were terminated. This represents 34.9% of all delivered and prenatally detected DS cases from this period. The overall livebirth prevalence was 1.17 per 1000 livebirths. The livebirth prevalence in group I was 1.25 and in group II was 1.09 per 1000 livebirths. The second trimester maternal serum screening with advanced maternal age screening was more effective than advanced maternal age screening alone. The livebirth prevalence in group IIa was 1.22 and in group IIb 0.99 per 1000 livebirths. Overall, regular trisomy was found in 90.4%, translocation in 6.3% and mosaicism in 2.9%. The overall male to female sex ratio of DS was 1.09.

Masticatory dysfunction in persons with Down’s syndrome. Part 1: aetiology and incidence

“…Down's syndrome is an autosomal chromosome anomaly resulting from trisomy of all or a critical part of the twenty-first chromosome. The incidence of Down's syndrome births varies between authors and countries from 0AE14 to 1AE66 in 1000 live births (1)(2)(3)(4)(5)(6)(7). Currently, the incidence of Down's syndrome births is decreasing slightly in countries where antenatal screening and pregnancy termination are legal, despite increased maternal age (8,9).…”

Giving and Withholding of Information following Genomic Screening: Challenges Identified in a Study of Primary Care Physicians in Estonia

“…Counseling skills 77.8%, n=42 Pharmacogenetics 74.1%, n=40 *The option "other" provided the opportunity for open-ended comments services financed by the national health insurance. Currently, there are two genetic counseling centers in Estonia (Reimand et al, 2006), and counseling is provided by medical geneticists, obstetricians or other specialists, such as oncologists. However, the Estonian HGRA, the law regulating the EGCUT and the Estonian Biobank, states that "Gene donors have the right to access personally their data stored in the Gene Bank" and "Gene donors have the right to genetic counseling upon accessing their data stored in the Gene Bank."…”