Cardiometabolic Risk and Body Composition in Youth With Down Syndrome

Abstract

Background and objectives: Whether BMI captures adiposity and cardiometabolic risk in Down syndrome (DS), a condition associated with obesity, short stature, and altered body proportions, is not known. We compared cardiometabolic risk measures in youth with DS and typically developing matched controls.

Methods: Youth with (n = 150) and without (n = 103) DS of comparable age (10-20 years), sex, race, ethnicity, and BMI percentile underwent whole-body dual-energy X-ray absorptiometry, fasting glucose, insulin, lipids, lipoprotein particles, inflammatory factors, and when BMI percentile ≥85, an oral glucose tolerance test.

Results: Sixty-four percent of youth with DS had BMI percentile ≥85. Among these, no difference in glucose, insulin, or insulin resistance was detected, but prediabetes was more prevalent with DS (26.4% vs 10.3%; P = .025) after adjustment for demographics, pubertal status, and BMI z score (odds ratio = 3.2; P = .026). Among all participants, those with DS had higher low-density lipoprotein cholesterol (median 107 [interquartile range 89-128] vs 88.5 [79-103] mg/dL; P < .00005), triglycerides (89.5 [73-133] vs 71.5 [56-104] mg/dL; P < .00005), non-high-density lipoprotein cholesterol (non-HDL-C; 128 [104-153] vs 107 [92-123] mg/dL; P < .00005), and triglycerides/HDL-C (2.2 [1.6-3.4] vs 1.7 [1.1-2.5] mg/dL; P = .0003) and lower levels of HDL-C (41 [36.5-47] vs 45 [37-53] mg/dL; P = .012). DS youth had higher high-sensitivity C-reactive protein, interleukin-6, small low-density lipoprotein particles (LDL-P), and total LDL-P, but similar LDL-P size. Youth with DS had less visceral fat (VFAT), fat mass, and lean mass for BMI z score, but greater VFAT at higher fat mass. However, VFAT did not fully explain the increased prevalence of dyslipidemia or prediabetes in youth with DS.

Conclusions: Despite similar insulin resistance, youth with DS had greater prevalence of dyslipidemia and prediabetes than typically developing youth, which was not fully explained by VFAT.

Trial registration: ClinicalTrials.gov NCT01821300.

Conflict of interest statement

POTENTIAL CONFLICT OF INTEREST: The authors have indicated they have no potential conflicts of interest to disclose.

Copyright © 2019 by the American Academy of Pediatrics.

Figures

FIGURE 1

Dyslipidemia in those with normal BMI versus those with overweight and obesity. A, Prevalence of dyslipidemia among those with normal BMI percentile. Categorical variables were compared by using Fisher’s exact test (those with DS: n = 54; control patients: n = 38). B, Prevalence of dyslipidemia among those with overweight or obesity. Categorical variables were compared by using Fisher’s exact test (those with DS: n = 92; control patients: n = 63). * P < .00005; ** P = .004.

FIGURE 2

A, Increased non-HDL-C level with increasing BMI z score in individuals with DS versus control patients. P = .033 for interaction, with adjustment for age, sex, race, ethnicity, and pubertal stage. B, Increased LDL-C level with increasing BMI z score in individuals with DS versus control patients. P = .032 for interaction, with adjustment for age, sex, race, ethnicity, and pubertal stage. The graphs reveal relationships of nontransformed data without adjustment for covariates.

FIGURE 3

A, Decreased fat mass for BMI z score in individuals with DS. P < .0005, with adjustment for age, sex, race, ethnicity, and pubertal stage. B, Increase visceral fat at higher fat mass in individuals with DS. P = .002 for interaction, with adjustment for age, sex, race, ethnicity, and pubertal stage. The graphs reveal relationships of nontransformed data without adjustment for covariates.