Estonian Children Research Articles

Stability of the factorial structure of metabolic syndrome from childhood to adolescence: a 6-year follow-up study

BackgroundMetabolic syndrome (MS) is a clustering of cardiometabolic risk factors that is considered a predictor of cardiovascular disease, type 2 diabetes and mortality. There is no consistent evidence on whether the MS construct works in the same way in different populations and at different stages in life.MethodsWe used confirmatory factor analysis to examine if a single-factor-model including waist circumference, triglycerides/HDL-c, insulin and mean arterial pressure underlies metabolic syndrome from the childhood to adolescence in a 6-years follow-up study in 174 Swedish and 460 Estonian children aged 9 years at baseline. Indeed, we analyze the tracking of a previously validated MS index over this 6-years period.ResultsThe estimates of goodness-of-fit for the single-factor-model underlying MS were acceptable both in children and adolescents. The construct stability of a new model including the differences from baseline to the end of the follow-up in the components of the proposed model displayed good fit indexes for the change, supporting the hypothesis of a single factor underlying MS component trends.ConclusionsA single-factor-model underlying MS is stable across the puberty in both Estonian and Swedish young people. The MS index tracks acceptably from childhood to adolescence.

Lack of Association Between PCK1 Polymorphisms and Obesity, Physical Activity, and Fitness in European Youth Heart Study (EYHS)

Phosphoenolpyruvate carboxykinase-1 (PCK1) is the rate-limiting enzyme in the hepatic gluconeogenic pathway. Studies have shown that overexpression of Pck1 in mice results in obesity-related traits and higher levels of physical activity (PA). Therefore, our aims were to investigate whether common genetic variation in the PCK1 gene influences obesity-related traits, PA, and fitness, and to examine whether PA and fitness attenuate the influence of the PCK1 polymorphisms on obesity in children. Analyses were undertaken on data from Danish and Estonian children (958 boys and 1,104 girls) from the European Youth Heart Study (EYHS), a school-based, cross-sectional study of children (mean ± s.d. age: 9.6 ± 0.4 years) and adolescents (15.5 ± 0.5 years). We genotyped eight polymorphisms that captured the common genetic variations in the PCK1 gene. The association between the PCK1 polymorphisms and BMI, waist circumference (WC), sum of four skinfolds, PA, and fitness was tested using an additive model adjusted for age, age-group, gender, maturity, and country. Interactions were tested by including interaction terms in the model. None of the polymorphisms were significantly associated with BMI, WC, sum of four skinfolds, PA, and fitness, and also with the risk of being overweight or obese (P > 0.05). The interactions between the polymorphisms and age-group, gender, PA, and fitness were not statistically significant. This is the first study to comprehensively examine the association of PCK1 polymorphisms with obesity, PA, and fitness. Despite strong evidence from animal studies, our study in the EYHS cohort failed to identify an association of PCK1 polymorphisms with obesity, PA, and fitness.

Active commuting to school in children and adolescents: An opportunity to increase physical activity and fitness

The purpose was to describe the patterns of commuting to school in young people and to examine its associations with physical activity (PA) and cardiorespiratory fitness. The sample comprised 2271 Estonian and Swedish children and adolescents (1218 females) aged 9-10 years and 15-16 years. Data were collected in 1998/99. Mode of commuting to and from school was assessed by questionnaire. Time spent (min/day) in PA and average PA (counts/min) was measured by accelerometry. Cardiorespiratory fitness was assessed by means of a maximal cycle ergometer test. Sixty-one percent of the participants reported active commuting to school (ACS). Estonian youth showed lower levels of ACS than Swedish (odds ratio, 0.64; 95% confidence interval, 0.53-0.76) and girls reported lower levels than boys (0.74; 0.62-0.88). ACS boys showed higher PA levels than non-ACS boys for moderate, vigorous, MVPA, and average PA levels (all p ≤ 0.01). Participants who cycled to school had higher cardiorespiratory fitness than walkers or passive travellers (p < 0.001). Nearly two-thirds of the participants actively commuted to school. ACS may provide an opportunity to increase levels of daily PA, especially in boys, and cardiorespiratory fitness, especially if cycling. Public health strategies should develop and test ACS patterns to get more evidence and promote bike-friendly environments.

Macrostructure in the Narratives of Estonian Children With Typical Development and Language Impairment

This study examined the macrostructure in Estonian children's narratives according to the story grammar (SG) model. The study's aims were to determine whether differences exist in narrative macrostructure between Estonian- and English-speaking children, among typically developed (TD) children, and between children with and without language impairment (LI). A clinical group of 18 children with LI (ages 6-8) and a control group of 216 TD children (ages 6-7), divided into 3 language competence subgroups, participated in the study. Narratives were analyzed for the presence of SG components and quantity of story information units. Estonian children's narratives reflected age-expected SG structures similar to those of children in English-speaking countries. The analyses revealed significant group influences for the setting category, demonstrating the superior skills of TD children with high language competence in starting stories, compared with their peers. The quantity of story information units differed significantly between the high and low language competence TD subgroups, likewise between the control and the clinical groups. The contrasts between stories of TD children and between TD and LI children are discussed. The findings support the suitability of the SG model in terms of quantity of story information units for language assessment.

Laste esimesed eestikeelsed omadussõnad

Analysis of the recordings of three boys from the ages of 18 months until 4 years acquiring Estonian naturally in differing language environments indicated that Estonian adjectives increased relatively slowly and thus were less numerous in their recording lexicons than verbs and nouns. Adjectival rate of increase appeared to be relatively independent of a child’s macro-environment (as long as there is an Estonian-speaking carer to provide sufficient input), yet it seemed to be influenced by a child’s individual linguistic abilty. The boys started qualifying their nouns with adjectives by calling things beautiful, good and bad, small and big, old and new. Antonymous pairs of adjectives and evaluative adjectives appeared early in their speech. Adjectival commonality – defined in terms of the number of the same words used by several individuals – between individual boys, the Estonian boys and children learning English, as well as the Estonian boys and adults, indicated that the observed boys’ adjectives were representative of currently spoken Estonian, as well as possibly common in the early speech of all children.

Prevalence of c.35delG and p.M34T mutations in the GJB2 gene in Estonia

Objective The purpose of this study was to determine the prevalence of c.35delG and p.M34T mutations in the GJB2 gene among children with early onset hearing loss and within a general population of Estonia. Methods Using an arrayed primer extension assay, we screened 233 probands with early childhood onset hearing loss for 107 different mutations in the GJB2 gene. We then looked for the two most common mutations, c.35delG and p.M34T, in a population of 998 consecutively born Estonian neonates to determine the frequency of these mutations in the general population. Results In 115 (49%) of the patients with early onset hearing loss, we found a mutation in at least one allele of the GJB2 gene. Seventy-three (31%) were homozygous for the c.35delG mutation, seven (3%) were homozygous for the p.M34T mutation, and five (2%) had c35delG/p.M34T compound heterozygosity. Other six identified mutations in GJB2 gene occurred rarely. Among the 998 anonymous newborn samples, we detected 45 who were heterozygous for c.35delG, 2 individuals homozygous for c.35delG, and 58 who were heterozygous for p.M34T. Additionally, we detected two c.35delG/p.M34T compound heterozygotes. Conclusion The most common GJB2 gene mutations in Estonian children with early onset hearing loss were c.35delG and p.M34T, with c.35delG accounting for 75% of GJB2 alleles. The carrier frequency for c.35delG and p.M34T in a general population of Estonia was 1 in 22 and 1 in 17, respectively, and was higher than in most other countries.

Sexual Behavior, Depressive Feelings, and Suicidality Among Estonian School Children Aged 13 to 15 Years

The present paper is based on a WHO Collaborative Cross-National Study "Health Behavior in School-Aged Children (HBSC)." It aimed at describing and analyzing how the sexual behaviors of 13- to 15-year-old Estonian school children were associated with self-reported depressive feelings and suicidality. Distinctive behavioral traits in relation to age of first sexual intercourse were also investigated. Self-reported questionnaires from school children (n = 3,055) were analyzed. In total, 15.2% of school children reported being nonvirgin. Among 13-year-olds, 2.9% of girls and 6.8% of boys were nonvirgins. Approximately 25% of the 15-year-old girls and boys were nonvirgins. The likelihood of depressive feelings and suicidal ideation increased significantly in both genders with loss of virginity. Boys who had lost their virginity at 13 years or younger were 4.2 times more likely to have suicidal thoughts; comparable girls were 7.8 times more likely to have suicidal thoughts. Compared to virgins, youths who had lost their virginity reported poor self-assessed health and more risk behaviors in themselves and their peers. Experiences of sexual intercourse increased the odds ratios for depressive feelings and suicidality. The earlier sexual intercourse was initiated, the greater were the odds of lower mental well-being. Risk behaviors emerged as a complex phenomenon requiring complex prevention.

Qualities to be developed in Estonian children at home and at school

The study examined the views of 580 mothers, 333 fathers and 43 primary school teachers about qualities to be developed at home and at school in Estonia — a country in transition with reforms towards child-centered democratic education. The study found that mothers, fathers and teachers shared the dominant family socialization values. Mothers, fathers and teachers concordantly stressed the importance of creativity to be developed at school. Teachers, differently from parents, did not consider smartness as a quality to be developed at school. Different socializers — mothers, fathers and teachers — are likely to manifest the pattern of autonomous relatedness (Kagitçibaşi, 1996, 2005) both in family and school socialization. They have a value system where values related to self-direction co-exist with those of social values. In line with this perspective, the study also showed that family socialization was more interdependently oriented whereas socialization at school was independently oriented.

Cultural, contextual, and gender differences in peer talk: A comparative study

The study focused on cultural, contextual, and gender differences in children's peer talk. Same-sex dyads of Estonian (n = 38), Finnish (n = 38), and Swedish (n = 34) preschool age children were videotaped during unstructured and structured play settings. We found only one gender difference in children's talkativeness and in the use of regulatory speech: during free play, Swedish boys used more imperatives per directives than Swedish girls. At the same time there were significant cultural and contextual differences. Estonian children were most directive and Swedish children were least directive. Finnish children were less directive than Estonian children but more directive than Swedish children. It was concluded that cultural and contextual factors strongly influence the likelihood, extent, and nature of gender differences in peer talk.

Laps(epõlv) 19. sajandi teise poole Eestis omaelulooliste tekstide näitel. Child(hood) in 19th Century Estonia: a Study of Autobiographical Texts

Laps(epõlv) 19. sajandi teise poole Eestis omaelulooliste tekstide näitel. Child(hood) in 19th Century Estonia: a Study of Autobiographical Texts

The role of individual and contextual factors in the development of maths skills

In this study, we examined the development of maths skills in 269 Estonian primary school children (119 boys and 150 girls; 20 classes). Testing was carried out over a three‐year period (Grade 1–Grade 3). Before the last testing session, children’s verbal skills and motivational orientations were also tested. In addition, teachers evaluated children’s learning behaviour and provided information about their own teaching methods. The data were analysed using multilevel growth curve modelling. We found that children with higher levels of pre‐maths skills developed at a faster rate. At the individual level, pre‐maths skills and verbal ability were positively associated with maths achievement in Grade 3, and avoidance orientations (self‐reported) and task‐avoidant behaviour (teacher‐reported) were negatively associated with maths achievement in Grade 3. At the classroom level, formalist teaching methods and teacher experience had a positive effect on students’ maths performance.

Absence of Association Between the INSIG2 Gene Polymorphism (rs7566605) and Obesity in the European Youth Heart Study (EYHS)

The first genome-wide association study for BMI identified a polymorphism, rs7566605, 10 kb upstream of the insulin-induced gene 2 (INSIG2) transcription start site, as the most significantly associated variant in children and adults. Subsequent studies, however, showed inconsistent association of this polymorphism with obesity traits. This polymorphism has been hypothesized to alter INSIG2 expression leading to inhibition of fatty acid and cholesterol synthesis. Hence, we investigated the association of the INSIG2 rs7566605 polymorphism with obesity- and lipid-related traits in Danish and Estonian children (930 boys and 1,073 girls) from the European Youth Heart Study (EYHS), a school-based, cross-sectional study of pre- and early pubertal children. The association between the polymorphism and obesity traits was tested using additive and recessive models adjusted for age, age-group, gender, maturity and country. Interactions were tested by including the interaction terms in the model. Despite having sufficient power (98%) to detect the previously reported effect size for association with BMI, we did not find significant effects of rs7566605 on BMI (additive, P = 0.68; recessive, P = 0.24). Accordingly, the polymorphism was not associated with overweight (P = 0.87) or obesity (P = 0.34). We also did not find association with waist circumference (WC), sum of four skinfolds, or with total cholesterol, triglycerides, low-density lipoprotein, or high-density lipoprotein. There were no gender-specific (P = 0.55), age-group-specific (P = 0.63) or country-specific (P = 0.56) effects. There was also no evidence of interaction between genotype and physical activity (P = 0.95). Despite an adequately powered study, our findings suggest that rs7566605 is not associated with obesity-related traits and lipids in the EYHS.

Increasing incidence of childhood-onset type 1 diabetes mellitus among Estonian children in 1999-2006. Time trend analysis 1983-2006

The incidence of childhood-onset type 1 diabetes mellitus (T1DM) among Estonian children under 15 years of age was 10.1 per 100,000 per year in 1983-1990 and 12.2 per 100,000 per year in 1991-1998 with the highest incidence in age-group 10.0-14.9 years in both periods. From 1983 to 1998, the incidence increased most rapidly in age-group 0-4.9 years. To determine the incidence of T1DM among Estonian children in 1999-2006 and to compare the results with the data from 1983 to 1998. In 1999-2006, population-based incidence data were collected from two centers where all children with T1DM are seen after the diagnosis. Data for earlier periods were obtained from previously published data. Subjects were divided into three age-groups: 0-4.9 years, 5.0-9.9 years and 10.0-14.9 years. Between 1999 and 2006, 310 new cases of T1DM were diagnosed in Estonian children aged 0-14.9 years. The age-standardized incidence rate for that period was 17.2 [95% confidence interval (CI) 13.1-21.2]. The incidence was the highest, 21.2 (95% CI 17.7-25.3) in age-group 5.0-9.9 years. Over the time period 1983-2006, the incidence of childhood-onset T1DM in Estonian children under 15 years of age increased annually by an average 3.3% with the most rapid annual increase-9.3%-occurring in the youngest age-group. The incidence of childhood-onset T1DM in Estonia continues to rise and the age of onset of the disease becomes younger.

Chromium nitrate as a source of chromium added for nutritional purposes to food supplements

Chromium nitrate as a source of chromium added for nutritional purposes to food supplements

Edgar Valter: Estonia’s Master of Art and Imagination in Picture Books

Illustrator and author Edgar Valter created stories and characters that have become household names in Estonian children’s culture. Here we have a glimpse of his life, his work, and his legacy.

Comprehension and production of noun compounds by Estonian children with specific language impairment

The authors examined how 12 Estonian‐speaking children with specific language impairment (SLI) and 60 children with normal speech development (ND) comprehended compound nouns with differing sequence of the components (first task) and how they produced compound nouns to label genuine and accidental categories by using analogy (second task) and sentence transformation (third task). The results demonstrated that children with SLI were capable of producing compound nouns for genuine categories, but avoided production of compounds to label objects in temporary juxtapositions. However, by comparison with the control group, SLI children differed statistically significantly in terms of both the number of correct answers and the pattern of mistakes. In the cases when compound nouns were expected to be produced by transforming sentences, the results of SLI children were considerably lower than those of their peers. The results of this study support the idea that children with SLI experience difficulties related to processing linguistic information.

How do preschool children engage each other in dialogue in Finland, Estonia and Sweden?

Abstract The present study compares preschool children in Finland, Estonia and Sweden regarding linguistic structures with which children in dyads elicited talk from each other in a naturalistic play activity. Nineteen Finnish (mean age 5.1), 19 Estonian (mean age 5.4) and 17 Swedish (mean age 5.1) same-sex pairs were video-recorded by a native researcher. Analyses of the results showed that children in different groups produced quite a similar number of utterances and eliciting talk structures. The Swedish and Finnish children used most yes-no questions, whereas the Estonian children had the highest occurrence of open questions. Imperative as well as elliptic structures were used by the Finnish children to a significantly higher extent than by the Swedish children. In summary, the groups differed less from each than was predicted on the basis of adult–child interaction. The results suggested that the symmetrical child–child free play context affected the choice of eliciting talk structures.

Somatotype in 6–11-year-old Italian and Estonian schoolchildren

The study of somatotypes can contribute to the understanding of variability in human body build. The aim of this study was to compare the somatotypes of Italian and Estonian schoolchildren in order to evaluate factors that might lead to variability in somatotypes. The sample consisted of 762 Italian and 366 Estonian children aged 6–11 years. They were somatotyped by the Heath-Carter anthropometric method. Data on organised extra-curricular physical activity and hours of weekly training were also collected. One-way ANOVA was used to evaluate country-related variations of somatotype in each age/sex group, while factorial ANOVA was used to test the influence of country and organised physical activity on the variability of the anthropometric characteristics and somatotype components. There are significant differences in mean somatotypes between the Italian and Estonian children in many age classes and a different constitutional trend in children from the two different countries is observed. The Italian children are more endomorphic and less mesomorphic and ectomorphic than the Estonian children. On the other hand, it emerges from factorial ANOVA, that the somatotype components do not present significant variations related to organised physical activity and to the interaction between the country of origin and sport practice. Moreover, the results of the forward stepwise discriminant analyses show that mesomorphy is the best discriminator between the two countries, followed by ectomorphy. Our findings suggest that the observed differences between Italian and Estonian children could be related mainly to country rather than to the practice of organised physical activity in the two countries.

Longitudinal Stability of Sedentary Behaviors and Physical Activity during Early Adolescence

The purpose of this study was to examine the stability of sedentary behaviors and physical activity in Estonian school children aged 11-12 year at the beginning of the study. In addition, the consequence of changes in sedentary behaviors on a change in physical activity was investigated. Adolescents (N = 345) completed the 3-Day Physical Activity Recall on four occasions over a 22-month period. Results indicated the curvilinear changes in sedentary behaviors and physical activity across time. There was a significant decrease in physical activity and an increase in sedentary behaviors across three years. Stability coefficients indicated a moderate differential stability of the sedentary behaviors (ranged from 0.31 to 0.64) and physical activity (ranged from 0.36 to 0.59) during early adolescence. Latent growth modeling indicated that increase in sedentary behaviors across a 22-month period was inversely associated with a change in physical activity. Interventions targeted at "high-risk" groups to reduce sedentary behaviors during early adolescence are encouraged.

Associations between an alpha 2a adrenergic receptor gene polymorphism and adolescent personality

The aim of this study was to investigate the impact of the C-1291G polymorphism in the promoter region of the alpha 2A adrenoreceptor gene (ADRA2A) to the personality traits. In the present study, data of the younger cohort of the Estonian Children Personality Behaviour and Health Study was used (N = 419). Personality traits were assessed by 240-item (Estonian Personality Item Pool NEO (EPIP-NEO)). Restriction enzyme MspI was used after PCR amplification to genotype the subjects according to C-1291G polymorphism of the ADRA2A. There were no significant differences on the level of the Big Five personality domains between genotypes; however, there were three significant differences on the level of different subscales. The subjects with GG genotype had significantly higher scores on Depression and significantly lower scores on Morality and Orderliness compared to subjects with CC and CG genotypes. There was a significant interaction between sex and ADRA2A polymorphism regarding E1, Friendliness; E2, Gregariousness; and E6, Cheerfulness. With CC and CG genotypes girls had higher scores on extraversion scales than boys, but with GG genotype boys score higher than girls with GG genotype. It is concluded that the gene polymorphism in the ADRA2A has an influence on personality traits in adolescents.