Insulin tolerance test is comparable to homeostasis model assessment for insulin resistance in patients with nonalcoholic fatty liver disease.

ABSTRACT

INTRODUCTION: Insulin resistance (IR) is common in patients with nonalcoholic fatty liver disease (NAFLD). We compared the performance of insulin tolerance test and the homeostasis model assessment (HOMA) for measuring IR in such patients. METHODS: In a prospective study, IR was determined using both insulin tolerance test and HOMA in 22 patients with NAFLD. Rate constant for insulin tolerance test (KITT) was calculated using the formula KITT (%/min) = 0.693/t(1/2), where t(1/2) was calculated from the slope of plasma glucose concentration during 3-15 minutes after administration of intravenous insulin. IR was assessed using HOMA as the product of fasting insulin (microU/L) and fasting plasma glucose (mmol/L) levels divided by 22.5. RESULTS: All the 22 patients had IR. Results of KITT and HOMA-IR for determining IR showed a fair correlation (r = 0.55; p = 0.03). CONCLUSIONS: Insulin tolerance test may be a useful method for assessing IR in patients with NAFLD.