Central Adiposity and Insulin Resistance in Youth with Type 1 Diabetes

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SUN 758-779-Cardiometabolic Risk & Vascular Biology
Clinical
Sunday, June 16, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SUN-775
Lisa K Volkening1, Charu Baskaran*1, Leah B Bellman1, Tonja R Nansel2, Leah M Lipsky2, Sanjeev N Mehta1 and Lori M Laffel1
1Joslin Diabetes Center, Boston, MA, 2Eunice Kennedy Shriver National Institute of Child Health & Human Development, Bethesda, MD
Adiposity and body fat distribution are associated with insulin resistance, metabolic syndrome, and diabetes. Given the epidemic of childhood obesity, youth with type 1 diabetes (T1D) experience overweight/obesity and are at risk for insulin resistance. To assess adiposity and its association with insulin resistance and components of metabolic syndrome in T1D, we measured body fat distribution by DXA in 126 T1D youth. DXA provided % body fat (%BF) and trunk-to-periphery fat ratio (TPFR) to estimate central (trunk) vs peripheral (arms+legs) body fat.

We categorized youth by sex-specific TPFR tertile and compared the lower 2 tertiles to the upper tertile. Statistical analyses included Pearson and partial correlations, unpaired t tests, and chi-square tests. Youth (49% male, 89% white) were aged 12.9±2.5 (mean±SD) years and had T1D for 5.9±3.2 years; A1c was 8.1±1.1% and 72% received insulin pump therapy.

Insulin dose was correlated with age (r=.24, p<.01), A1c (r=.32, p<.001), %BF (r=.33, p<.001), and TPFR (r=.31, p<.001); TPFR was correlated with age (r=.36, p<.0001), %BF (r=.49, p<.0001), diastolic BP percentile (r=.18, p<.05), cholesterol (r=.23, p=.01), HDL (r=-.20, p<.03), LDL (r=.22, p<.02), and triglycerides (r=.33, p=.0002). After controlling for %BF, TPFR remained correlated with age (r=.38, p<.0001) and triglycerides (r=.20, p<.03). Mean TPFR was 0.6±0.1 in the lower 2 TPFR tertiles (n=84) and 0.9±0.1 in the upper TPFR tertile (n=42) (p<.0001). Youth in the upper TPFR tertile, compared to youth in the lower 2 tertiles (upper vs. lower 2 tertiles for all), were older (13.7±2.5 vs. 12.5±2.4 years, p=.02) and had longer T1D duration (6.8±3.5 vs. 5.5±2.9 years, p=.03), higher insulin dose (1.0±0.3 vs. 0.9±0.3 U/kg/day, p=.04), and higher z-BMI (1.1±1.1 vs. 0.5±0.6, p=.003). The upper TPFR tertile, compared to the lower 2 tertiles (upper vs. lower 2 tertiles for all), had more obesity (38 vs. 1%, p<.0001), higher %BF (32.6±9.0 vs. 25.3±6.2, p<.0001), and higher triglycerides (138±81 vs. 106±51 mg/dL, p=.02). Systolic and diastolic BP percentiles, cholesterol, HDL, and LDL did not differ significantly by tertile grouping. A1c also did not differ by tertile grouping, suggesting that youth with higher TPFR required more insulin to achieve similar A1c levels to those with lower TPFR.

Youth with T1D who have elevated central adiposity appear susceptible to components of the metabolic syndrome and warrant aggressive interventions to reduce future CVD risk.

Disclosure: LML: Consultant, Eli Lilly & Company, Consultant, LifeScan/Animas, Consultant, Johnson &Johnson, Advisory Group Member, Sanofi, Advisory Group Member, Bristol-Myers Squibb, Consultant, Menarini. Nothing to Disclose: LKV, CB, LBB, TRN, LML, SNM

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm

Sources of Research Support: NICHD contract HHSN267200703434C; NIH Training Grant 5 T32 DK007260-36