Childhood Metabolic Markers of Adult Morbidity in Blacks

Blacks are at increased risk for obesity, type 2 diabetes mellitus and cardiovascular disease. A common pathogenetic link among these entities is insulin resistance/hyperinsulinemia.

The specific aims of this project are: 1) to compare skeletal muscle lipid content (SMLC) in black vs white children by computed tomography (CT) scan of the mid-thigh, and assess the relationship to in vivo insulin sensitivity; 2) to test the hypothesis that free fatty acid (FFA) - induced insulin resistance is associated with larger increases in intramyocellular lipid (IMCL) in black vs white adolescents; 3) to examine if β-cell insulin secretion in prepubertal black children is more sensitive to the stimulatory effect of FFA than in whites; and 4) to test if the β-cell in black obese adolescents is more susceptible to the lipotoxic effect of FFA compared with whites. The methods to be used are: the well- established CT method as well as Magnetic Resonance Spectroscopy (1H-MRS) to assess SMLC and IMCL; intralipid infusion to elevate circulating FFA levels; the hyperinsulinemic-euglycemic clamp with stable isotopes and indirect calorimetry to measure insulin sensitivity and substrate turnover; the hyperglycemic clamp to assess insulin secretion; DEXA and whole body MRI for body composition assessments.

Study Overview

• Status: Completed
• Conditions: Healthy; Overweight; Normal Weight

• Study Type: Observational
• Enrollment (Actual): 156

Contacts and Locations

Study Locations

• United States
  • Pennsylvania
    • Pittsburgh, Pennsylvania, United States, 15224
      • Children's Hospital of Pittsburgh of UPMC

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 8 years to 17 years (Child)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Healthy black and white volunteers who are 8 to 17 years of age

Description

Inclusion Criteria:

Protocols 1 & 4:

• Age 11-17 years
• Male or Female
• Healthy
• Obese, BMI ≥ 95 percentile
• Pubertal/Tanner Stage II-V
• African American or White American, based on self identity with no admixture for 3 generations

Protocol 2:

• Age 11-17 years
• Male or Female
• Healthy
• Normal Weight, BMI 10- 95 percentile
• Pubertal/Tanner Stage II-V
• African American or White American, based on self-identity with no admixture for 3 generations

Protocol 3:

• Age 8-12 years
• Male or Female
• Healthy
• Normal Weight, BMI 10-95 percentile
• Prepubertal/Tanner Stage I
• African American or White American, based on self-identity with no admixture for 3 generations

Exclusion Criteria:

• Medications which interfere with metabolism
• Hemocue < 12 gm/dl in pubertal subjects and <11gm/dl in prepubertal subjects
• Positive serum pregnancy test
• Recent significant weight change or dieting
• Presence of disease (i.e.diabetes, hypothyroidism, genetic dyslipidemia, etc)

Study Plan

How is the study designed?

Design Details

• Observational Models: Other
• Time Perspectives: Cross-Sectional

Number of groups / cohorts

4

Cohorts and Interventions

Group / Cohort
Protocol 1; Healthy, overweight 11 to 17 year old black and white adolescents
Protocol 2; Healthy, normal-weight 11 to 17 year old black and white adolescents
Protocol 3; Healthy, normal-weight 8 to 12 year old black and white adolescents
Protocol 4; Healthy, overweight 11 to 17 year old black and white adolescents

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Skeletal muscle lipid content, insulin sensitivity and insulin secretion	Assessments at 2 timepoints occur within a 2 to 3 week period

Collaborators and Investigators

• Sponsor: University of Pittsburgh
• Collaborators: National Institutes of Health (NIH)

Study record dates

Study Major Dates

• Study Start: July 1, 2004
• Primary Completion (Actual): September 20, 2011
• Study Completion (Actual): September 20, 2011

Study Registration Dates

• First Submitted: March 9, 2011
• First Submitted That Met QC Criteria: March 9, 2011
• First Posted (Estimate): March 10, 2011

Study Record Updates

• Last Update Posted (Actual): October 18, 2017
• Last Update Submitted That Met QC Criteria: October 16, 2017
• Last Verified: October 1, 2017

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Body Weight; Overweight
• Other Study ID Numbers: R01HD027503 (U.S. NIH Grant/Contract)