Utility of a surrogate measure of insulin resistance in American Indians: the Strong Heart Study

Ethn Dis. Fall 2002;12(4):523-9.

Abstract

Objective: 1) Determine in a sample of American Indians (AI) how well insulin sensitivity (SI) measured by the frequently sampled intravenous glucose test (FSIGT) correlates with a simpler measure of insulin resistance (IR) measured by the homeostasis assessment (HOMA) model; (2) compare insulin sensitivity in a sample of diabetic and non-diabetic Al in the Strong Heart Study (SHS) with that of White, Black, and Hispanic Americans in the Insulin Resistance Atherosclerosis Study (IRAS).

Design: Cross sectional

Setting: Community

Participants: Sixty-one Al participants in SHS MAIN OUTCOME MEASURES: Mean SI measured by FSIGT, a complex protocol to evaluate insulin sensitivity, and mean IR measured by the HOMA model, a method based on measures of fasting glucose and fasting insulin.

Results: Although 70% of sample participants were non-diabetic, only 18% were insulin sensitive by SI. Diabetes status strongly confounded Si among Al in SHS. At non-diabetic levels of fasting glucose (< 126 mg/dL), SI correlated well with HOMA IR (rho = -0.49, P = .0009), but SI did not reflect HOMA IR at levels of fasting glucose that are diagnostic of diabetes (> or = 126 mg/dL; rho = -0.13, P = n.s.). With the exception of some Hispanic participants in IRAS, mean SI of non-diabetic Al in SHS was lower than that of their non-diabetic IRAS counterparts. Diabetic Al participants in SHS had markedly lower mean SI than all diabetic participants in IRAS.

Conclusions: The HOMA model may be a useful tool to identify non-diabetic American Indians who might benefit from early CVD risk factor modification.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Cardiovascular Diseases / ethnology*
  • Cardiovascular Diseases / etiology
  • Cardiovascular Diseases / prevention & control
  • Case-Control Studies
  • Cross-Sectional Studies
  • Diabetes Complications
  • Diabetes Mellitus / drug therapy
  • Diabetes Mellitus / ethnology*
  • Diabetes Mellitus / metabolism*
  • Female
  • Glucose
  • Glucose Tolerance Test
  • Humans
  • Indians, North American*
  • Insulin Resistance*
  • Male
  • Middle Aged
  • Northwestern United States / epidemiology
  • Southwestern United States / epidemiology

Substances

  • Glucose