Clinical practice - latest insights in optimizing the care of children with Down syndrome

An essential part of the care of children with Down syndrome is secondary screening for comorbidity. It is well known that comorbidity frequently occurs in these children. A new update of the Dutch Down syndrome medical guideline was developed to create a sound evidence base for several of these conditions. We present the latest insights and recommendations from this Dutch medical guideline which are based on the most relevant literature currently available and developed with rigorous methodology. The main focus of this revision of the guideline was on obstructive sleep apnea and other airway problems and hematologic disorders, such as transient abnormal myelopoiesis, leukemia, and thyroid disorders. Conclusion: This is a short summary of the latest insights and recommendations from the updated Dutch medical guideline for children with Down syndrome.

Mainstream and special school attendance among a Dutch cohort of children with Down Syndrome

Object

To determine the level of mainstream education in a nationwide cohort of adolescents with Down Syndrome (DS), and to find characteristics related to mainstream or special school attendance.

Method

Dutch children with DS born in 1992, 1993 or 1994, were assessed when 16–19 years old. Parents scored school enrolment between the age of 4–18 years, general characteristics and the levels of intellectual disability using the Dutch Social Competence Rating Scale. Associations between disability and years in mainstream school were assessed by ordinal logistic regression, adjusting for sex and parental education.

Results

We collected data from 170 boys and 152 girls (response 63%); mean age 18.3 years (ranges 16.8–19.9). Intellectual disability was mostly moderate (43%). Most children (74%) entered mainstream education between 4 and 6 years of age. At 13 years 17% was in mainstream school and 7% stayed in up to 16 years. From the age of 8 years onwards the majority was in special education, while 6% never attended school. Girls were more often in mainstream school and stayed in longer. Level of disability was significantly associated with number of years in mainstream education.

Conclusion

Three out of four Dutch children with DS entered mainstream primary education, however late entry and high dropout are common.

Problem behavior of individuals with Down syndrome in a nationwide cohort assessed in late adolescence

OBJECTIVE

To assess problem behavior in adolescents with Down syndrome and examine the association with sex and severity of intellectual disability.

STUDY DESIGN

Cross-sectional data of a Dutch nationwide cohort of Down syndrome children aged 16-19 years were collected using a written parental questionnaire. Problem behavior was measured using the Child Behavior Checklist and compared with normative data. The degree of intellectual disability was determined using the Dutch Social competence rating scale.

RESULTS

The response rate was 62.8% (322/513), and the mean age 18.3 years (SD ± 0.8). The total score for problem behavior was higher in adolescents with Down syndrome than in adolescents without Down syndrome (26.8 vs 16.5; P < .001). Overall, 51% of adolescents with Down syndrome had problem scores in the clinical or borderline range on 1 or more Child Behavior Checklist subscales; this is more than twice as high as adolescents without Down syndrome. Adolescents with Down syndrome had more internalizing problems than their counterparts without Down syndrome (14% and 9%, respectively, in the clinical range); the percentages for externalizing problems were almost equal (7% and 9%, respectively, in the clinical range). The highest problem scores in adolescents with Down syndrome were observed on the social problems and thought problems subscales (large to very large standardized differences). Male sex and/or more severe mental disabilities were associated with more behavioral problems.

CONCLUSIONS

Serious problem behavior is more prevalent in adolescents with Down syndrome. This demonstrates the need for a focus on general behavior improvement and on the detection and treatment of specific psychopathology in individuals with Down syndrome.

Management of undescended testis: a decision analysis

BACKGROUND

Undescended testis (UDT) or cryptorchidism is the most common genital anomaly seen in boys and can be treated surgically by orchidopexy. The age at which orchidopexy should be performed is controversial for both congenital and acquired UDT.

METHODS

A decision analysis is performed in which all available knowledge is combined to assess the outcomes of orchidopexy at different ages.

RESULTS

Without surgery, unilateral congenital UDT and bilateral congenital UDT are associated with average losses in quality-adjusted life-years (QALYs) of 1.53 QALYs (3% discounting 0.66 QALYs) and 5.23 QALYs (1.91 QALYs), respectively. Surgery reduces this QALY loss to on average 0.84 QALYs (0.21 QALYs) for unilateral UDT and 1.66 QALYs (0.40 QALYs) for bilateral UDT. Surgery at detection will lead to the lowest QALY loss of 0.91 (0.34) and 1.73 (0.60) QALYs, respectively, for unilateral and bilateral acquired UDT compared with surgery during puberty and no surgery. No sensitivity analysis is able to change the preferences for these strategies.

CONCLUSIONS

Based on our decision analytic model using societal valuations of health outcomes, surgery for unilateral UDT (both congenital and acquired) yielded the lowest loss in QALYs. Given the modest differences in outcomes, there is room for patient (or parent) preference with respect to the performance and timing of surgery in case of unilateral UDT. For bilateral UDT (both congenital and acquired), orchidopexy at any age provides considerable benefit, in particular through improved fertility. As there is no strong effect of timing, the age at which orchidopexy is performed should be discussed with the parents and the patient. More clinical evidence on issues related to timing may in the future modify these results and hence this advice.

Prevalence of overweight in Dutch children with Down syndrome

OBJECTIVE

Prevalence of overweight in children is increasing, causing various health problems. This study aims to establish growth references for weight and to assess the prevalence rates of overweight and obesity in a nationwide sample of Dutch children with Down syndrome (DS), taking into account the influence of comorbidity.

METHODS

In 2009, longitudinal growth data from Dutch children with trisomy 21 who were born after 1982 were retrospectively collected from medical records of 25 Dutch regional specialized DS centers. "Healthy" was defined as not having concomitant disorders or having only a mild congenital heart defect. Weight and BMI references were calculated by using the LMS method, and prevalence rates of overweight and obesity by using cutoff values for BMI as defined by the International Obesity Task Force. Differences in prevalence rates were tested by multilevel logistic regression analyses to adjust for gender and age.

RESULTS

Growth data of 1596 children with DS were analyzed. Compared with the general Dutch population, healthy children with DS were more often overweight (25.5% vs 13.3% in boys, and 32.0% vs 14.9% in girls) and obese (4.2% vs 1.8%, and 5.1% vs 2.2%, respectively). Prevalence rates of overweight between DS children with or without concomitant disorders did not vary significantly.

CONCLUSIONS

Dutch children with DS have alarmingly high prevalence rates of overweight and obesity during childhood and adolescence. Health care professionals should be aware of the risk of overweight and obesity in children with DS to prevent complications.

Unchanged prevalence of Down syndrome in the Netherlands: results from an 11-year nationwide birth cohort

OBJECTIVE

This study aims to evaluate trends in prevalence of Down syndrome (DS) births in the Netherlands over an 11-year period and how they have been affected by maternal age and introduction of prenatal screening.

METHOD

Nationwide data of an 11-year birth cohort (1997-2007) from the Netherlands Perinatal Registry were analyzed. First-trimester combined screening was introduced in 2002, free of charge only for women 36 years of age or older and only on patients' request. Changes in maternal age, prevalence of DS births, and rates of births at <24 weeks (legal limit for termination of pregnancy in the Netherlands) during the study period were evaluated using logistic and linear regression analyses.

RESULTS

In total, 1,972,058 births were registered (91% of the births in 1997-2007). Mean prevalence of DS was 14.57 per 10,000 births (95% confidence interval 14.43; 14.73); 85% of DS were live births. No significant trend in overall prevalence of DS births was observed (p = 0.385), in spite of a significant increase of mean maternal age during the same period (p < 0.001). The increased prevalence of DS births at ≥ 24 weeks among women ≥ 36 years of age (p = 0.011) was offset by a significant increase in the proportion of DS births at <24 weeks among women aged <36 years (p = 0.013).

CONCLUSION

The proportion of DS births in the Netherlands has not changed during the period 1997-2007.

[Youth Healthcare guideline 'Skin disorders']

There is a high incidence of skin disorders; these are also frequently encountered within Youth Healthcare (YHC). Some skin disorders are caused by an underlying disease, syndrome or child abuse. Therefore, detection of these causes in an early stage is important. Skin disorders can have a huge psychosocial impact on both child and parents. This is one of the reasons why prevention, detection, diagnosis, treatment, referral, and uniform advice and guidance are of great importance. The YHC Guideline examines counselling and advice, criteria for referral to primary or secondary healthcare, and skincare in general. It also describes the disorders that should be actively detected. The Guideline also looks at specific aspects of dark skins and ethnic diversity, and the impact of skin disorders on general wellbeing. The accompanying web-based tool includes argumentation and opinions from experts on more than 75 skin disorders, including illustrations and decision trees, to aid the drawing up of a treatment plan.

Development, problem behavior, and quality of life in a population based sample of eight-year-old children with Down syndrome

Objective

Children with Down syndrome (DS) have delayed psychomotor development. We investigated levels of development, problem behavior, and Health-Related Quality of Life (HRQoL) in a population sample of Dutch eight-year-old children with DS. Developmental outcomes were compared with normative data of eight-year-old children from the general population.

Method

Over a three-year-period all parents with an eight-year-old child with DS were approached by the national parent organization. Developmental skills were assessed by means of the McCarthy Scales of Children's Ability. To measure emotional and behavioral problems we used the Child Behavior Checklist. HRQoL was assessed with the TNO-AZL Children's Quality of Life questionnaire. Analyses of variance were applied to compare groups.

Results

A total of 337 children participated. Mean developmental age was substantially lower than mean calendar age (3.9 years, SD 0.87 and 8.1 years, SD 0.15 respectively). Mean developmental age was significantly lower among boys than girls (3.6 (SD 0.85) and 4.2 years (SD 0.82) respectively; p<0.001). Compared with the general population, children with DS had more emotional and behavioral problems (p<0.001). However on the anxious/depressed scale, they scored significantly more favorably (p<0.001). Significantly lower HRQoL scores for the scales gross motor skills, autonomy, social functioning and cognitive functioning were found (p-values<0.001). Hardly any differences were observed for the scales physical complaints, positive and negative emotions.

Conclusion

Eight-year-old children with DS have an average developmental delay of four years, more often have emotional and behavioral problems, and have a less favorable HRQoL compared with children from the general population.