Relationships of Body Composition to Cardiac Structure and Function in Adolescents With Down Syndrome are Different than in Adolescents Without Down Syndrome

Senescent hearts from male Ts65Dn mice exhibit preserved function but altered size and nicotinamide adenine dinucleotide pathway signaling

Down syndrome (DS) is associated with congenital heart defects at birth, but cardiac function has not been assessed at older ages. We used the Ts65Dn mouse, a model of DS, to quantify heart structure and function with echocardiography in 18-mo male Ts65Dn and wild-type (WT) mice. Heart weight, nicotinamide adenine dinucleotide (NAD) signaling, and mitochondrial (citrate synthase) activity were investigated, as these pathways may be implicated in the cardiac pathology of DS. The left ventricle was smaller in Ts65Dn versus WT, as well as the anterior wall thickness of the left ventricle during both diastole (LVAW_d; mm) and systole (LVAW_s; mm) as assessed by echocardiography. Other functional metrics were similar between groups including left ventricular area end systole (mm2), left ventricular area end diastole (mm2), left ventricular diameter end systole (mm), left ventricular diameter end diastole (mm), isovolumetric relaxation time (ms), mitral valve atrial peak velocity (mm/s), mitral valve early peak velocity (mm/s), ratio of atrial and early peak velocities (E/A), heart rate (beats/min), ejection fraction (%), and fractional shortening (%). Nicotinamide phosphoribosyltransferase (NAMPT) protein expression, NAD concentration, and tissue weight were lower in the left ventricle of Ts65Dn versus WT mice. Sirtuin 3 (SIRT3) protein expression and citrate synthase activity were not different between groups. Although cardiac function was generally preserved in male Ts65Dn, the altered heart size and bioenergetic disturbances may contribute to differences in aging for DS.

Diet Quality and Cardiometabolic Risk Factors in Adolescents with Down Syndrome

BACKGROUND

Youth with Down syndrome (DS) have a high prevalence of obesity and dyslipidemia. Diet quality may influence cardiometabolic risk (CMR) in youth.

OBJECTIVE

The aim of this secondary analysis was to investigate the relationship between diet quality (Healthy Eating Index [HEI-2015]) with CMR factors in youth with DS compared with age, sex, race, ethnicity, and body mass index percentile matched, typically developing controls.

DESIGN

Adolescents (aged 10 to 20 years) with DS and controls of comparable age, sex, race, ethnicity, and body mass index percentile were recruited from 2012 to 2017 for a cross-sectional study from two large children's hospitals (Children's Hospital of Philadelphia and the Children's National Health System in Washington, DC).

PARTICIPANTS AND SETTING

CMRs in 143 adolescents with DS were compared with 100 controls. Exclusion criteria consisted of major organ-system illnesses.

MAIN OUTCOME MEASURES

The average of three 24-hour dietary recalls was used to calculate the HEI-2015. Anthropometrics, blood pressure, and fasting labs were collected.

STATISTICAL ANALYSES PERFORMED

Group differences were tested using Wilcoxon rank-sum tests. Relationships of CMR factors with HEI-2015 score within DS and controls were tested using linear regression models adjusted for sex, age, race, and body mass index z score.

RESULTS

Compared with controls (n = 100, median age = 14.8 years [interquartile range = 12.2 to 17.3 years]; 41% male; 24% African American; 65% with body mass index ≥85th percentile), adolescents with DS (n = 143, median age = 14.7 years [interquartile range = 11.4 to 17.4 years]; 44% male; 18% African American; 62% with body mass index ≥85th percentile) had higher scores (more aligned with dietary recommendations) for total HEI-2015 (DS: 52.7 [interquartile range = 46.8 to 58.6] vs controls: 45.1 [interquartile range = 39.5 to 55.0]; P < 0.0001). Youth with DS also had higher HEI-2015 component scores for fruits, greens/beans, dairy, refined grains, and saturated fats, but lower whole grains and sodium scores. Within the group with DS, total HEI-2015 was not significantly associated with CMR measures. Whereas HEI-2015 in the DS group was negatively associated with fasting glucose levels, the difference did not meet the set level of statistical significance (-0.14, 95% CI -0.29 to 0.00; P = 0.053).

CONCLUSIONS

Adolescents in both the control and DS groups reported low-quality diets, although the DS group had HEI-2015 scores more closely aligned with recommendations. In the DS group, diet quality was not significantly associated with CMR factors. Although further research is needed, these results suggest that dyslipidemia in youth with DS may not be related to dietary intake.

Cardiac Structure and Function in Adults with Down Syndrome

Various factors may alter the risk for cardiovascular disease in adults with Down syndrome (Ds), yet few studies have examined differences in cardiac physiology in this population. Previous research suggested lower systolic and diastolic function, but inconsistent methodologies and younger samples warrant research in adults with Ds. Our aim is to compare the cardiac structure and function of adults with Ds to age- and sex-matched adults without Ds. Echocardiography was used to assess systolic function, diastolic function, and cardiac structure in n = 19 adults (Ds n = 9, control n = 10). Regarding cardiac structure, adults with Ds had increased left ventricular posterior wall thickness at end-systole compared to adults without Ds (p = 0.007). Regarding systolic and diastolic function, adults with Ds were found to have lower septal peak systolic annular velocity (S') (p = 0.026), lower lateral and septal mitral annular early diastolic velocity (E') (p = 0.007 and p = 0.025, respectively), lower lateral peak mitral annular late diastolic velocity (A') (p = 0.027), and higher lateral and septal mitral annular early systolic velocity to diastolic velocity ratios (E/e') (p = 0.001 and p = 0.001, respectively). Differences in both cardiac structure and function were found when comparing adults with Ds to matched adults without Ds. Most of the differences were indicative of worse diastolic function.

Resistance training and Down Syndrome: A narrative review on considerations for exercise prescription and safety

The current manuscript reviews the literature on the health effects of resistance training (RT) for individuals with Down syndrome (DS), focusing on this training modality’s methodology, application, and safety. The literature has mentioned that early aging in this population is associated with loss of muscle strength, lower lean and bone mass, and increased obesity. It is necessary to propose non-pharmacological measures for prevention and health promotion. Thus, this review suggests a current research-based RT guide for individuals with DS. This review is divided into three sections: Section 2 briefly reviews DS and the effects on structural and functional decline and how exercise and physical activity can influence health aspects in this population; Section 3 summarizes the evidence for RT prescription; Section 4 briefly reviews the health and potential benefits of RT in individuals with DS. The findings from this review suggest that most individuals with DS should engage in moderate-intensity RT at least 2 days a week and perform RT on the major muscle groups and include balance training. The RT program should be modified and adapted according to individuals’ characteristics and limitations. RT promotes positive, health-related benefits such as increasing strength, improving body composition, improving functional capacity and balance, reducing inflammatory status and oxidative stress, and improving the immune system. The RT protocols summarized in this current review provide guidance, critical conclusions, and novel research settings, which could be useful to coaches, clinicians, and researchers to effectively design RT program for individuals with DS.

Relationship Between Postnatal Pulmonary Arterial Pressure and Altered Diastolic Function in Neonates with Down Syndrome

OBJECTIVE

To assess the influence of diastolic dysfunction on the evolution of pulmonary hypertension in neonates with Down Syndrome over the early newborn period.

STUDY DESIGN

This was a prospective observational cohort study. Echocardiography was performed three times over the first week of life in both Down syndrome and control cohorts. Measurements of pulmonary arterial pressure in addition to left ventricular (LV) and right ventricular systolic and diastolic function were collected.

RESULTS

Seventy babies with Down syndrome and 60 control infants were enrolled. Forty-eight of the infants with Down syndrome (69%) were born with congenital heart disease (CHD). Echocardiography surrogates of pulmonary hypertension and myocardial function remained significantly impaired in the Down syndrome group in comparison with control infants (all P < .01). In the Down syndrome group, LV early diastolic strain rate was independently associated with measures of pulmonary hypertension while controlling for gestational age, cesarean delivery, and the presence of CHD (P < .01).

CONCLUSIONS

Intrinsic LV diastolic impairment is directly associated with higher indices of pulmonary hypertension in infants with Down syndrome and may be a contributing factor to its evolution.

Comparison of the Upper and Lower Extremity and Trunk Muscle Masses between Children with Down Syndrome and Children with Typical Development

PURPOSE

Comparison of not only the upper and lower extremity but also trunk muscle masses measured by means of an ultrasound imaging device between children with Down syndrome (DS) and children with typical development (TD).

METHODS

The study included 35 children with TD (TD group) and 26 children with DS (DS group). The upper and lower extremity and trunk muscle thicknesses were measured using an ultrasound imaging device.

RESULTS

The thicknesses of the rectus abdominis, obliquus externus and internus abdominis, rectus femoris, and short head of the biceps femoris muscles were significantly lower in the DS group than in the TD group. The thicknesses of the other upper and lower extremity and trunk muscles did not differ significantly between the groups.

CONCLUSIONS

The results of this study demonstrated lower masses of trunk flexor and knee extensor and flexor muscles in children with DS compared to those in children with TD.

Prevalence of unsuspected abnormal echocardiograms in adolescents with down syndrome

The purpose of this article is to describe the prevalence of cardiac disease previously undiagnosed in healthy asymptomatic children and adolescents with Down syndrome (DS). Subjects with DS ages 10-20 years were recruited from two sites, the Children's Hospital of Philadelphia (Philadelphia, PA) and Children's National Health System (Washington, DC) for a cross-sectional study of body composition and cardiometabolic risk. Echocardiographic and clinical data were collected from patients enrolled in the parent study of cardiometabolic risk. Nine (6%) new cardiac diagnoses were identified out of 149 eligible patients. All new findings resulted in outpatient referrals to pediatric cardiology. Current guidelines recommend screening all newborns with DS for congenital heart disease. Older patients with DS may benefit from rescreening.