title: Racial and ethnic differences in an estimated measure of insulin resistance among individuals with type 1 diabetes.
abstract: OBJECTIVE Insulin resistance is greater in racial/ethnic minorities than in non-Hispanic whites (NHWs) for those with and without type 2 diabetes. Because previous research on insulin resistance in type 1 diabetes was limited to NHWs, racial/ethnic variation in an estimated measure of insulin resistance in type 1 diabetes was determined. RESEARCH DESIGN AND METHODS The sample included 79 individuals with type 1 diabetes diagnosed at age <18 years (32.9% NHWs, 46.8% non-Hispanic black [NHB], 7.6% other/mixed, and 12.7% Hispanic) and their families. Estimated glucose disposal rate (eGDR) (milligrams per kilogram per minute; a lower eGDR indicates greater insulin resistance) was calculated using A1C, waist circumference, and hypertension status. RESULTS Mean current age was 13.5 years (range 3.2-32.5) and diabetes duration was 5.7 years (0.1-19.9). eGDR was inversely associated with age. Compared with that in NHWs, age-adjusted eGDR was significantly lower among nonwhites (NHB, other/mixed, and Hispanic: Delta = -1.83, P = 0.0006). Age-adjusted eGDR was negatively associated with body fat, triglycerides, urinary albumin/creatinine, acanthosis nigricans, parental obesity, and parental insulin resistance and positively related to HDL and sex hormone-binding globulin. In multivariable analysis, lower eGDR was significantly associated with older age, nonwhite race/ethnicity, acanthosis, and lower HDL. CONCLUSIONS Minorities with type 1 diabetes are significantly more insulin resistant, as measured by eGDR, than NHWs. Exploring potential mechanisms, including disparities in care and/or physiological variation, may contribute to preventing racial/ethnic differences in insulin resistance-associated outcomes.
authors.affiliation: Institute for Endocrine Discovery and Clinical Care, University of Chicago, Chicago, Illinois, USA. kdaniels@peds.bsd.uchicago.edu
authors.forename: Kirstie K
authors.initials: KK
authors.lastname: Danielson
authors.forename: Melinda L
authors.initials: ML
authors.lastname: Drum
authors.forename: Carmela L
authors.initials: CL
authors.lastname: Estrada
authors.forename: Rebecca B
authors.initials: RB
authors.lastname: Lipton
mesh_terms: D000293:Adolescent; D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000175:diagnosis / Q000453:epidemiology / Q000208:ethnology* / Q000378:metabolism*; D003940:Diagnostic Techniques, Endocrine / Q000706:statistics & numerical data; D005006:Ethnicity / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D007333:Insulin Resistance / Q000208:ethnology*; D008297:Male; D044469:Racial Groups / Q000706:statistics & numerical data; D055815:Young Adult
chemical_list: D001786:Blood Glucose