HOMA-IR and HOMA2-IR estimation based on glycated hemoglobin as an alternative for fasting glucose

ABSTRACT

Background

Diabetes mellitus is a major global public health problem. Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) is a key laboratory index in the assessment of insulin resistance. The calculation of HOMA-IR and its updated version HOMA2-IR are partly based on plasma glucose determinations, which are prone to important pre-analytical errors. As glycated hemoglobin (Hb) fractions strongly correlate with fasting glucose levels and are more stable analytes, we explored the possibilities of using glycated Hb fractions for calculating HOMA-IR.

Methods

Labile Hb and HbA_1c fractions were simultaneously assayed on a Tosoh G8 analyzer and expressed as %. Fasting glucose was measured in fluoride plasma using a hexokinase method. A Lumipulse G1200 luminescence immunoassay was used to measure serum insulin. The HOMA-IR and HOMA2-IR values were compared to corresponding indices calculated using glucose and glycated Hb fractions.

Results

Labile Hb could be measured with between-run CVs of 2.2–2.3%. Labile Hb correlated with both glycemia (r = 0.80) and HbA_1c results (r = 0.73). HbA1c-derived estimated average glucose (eAG)-based HOMA calculation correlated very well with HOMA-IR (r² = 0.9972). Based on eAG calculations, HOMA2-IR (%B, %S, and IR) gave comparable results, as compared to labile Hb-based calculations, in particular for fasting plasma glucose values between 4.44 and 6.67 mmol/L.

Conclusions

HbA1c and eAG are practical alternatives for glucose for estimating HOMA-IR. The use of glycated Hb enables home sampling for HOMA-IR and HOMA2-IR calculation.

KEYWORDS:

• glucose
• glycated hemoglobin
• HOMA-IR
• labile hemoglobin fraction
• home sampling

Disclosure statement

No potential conflict of interest was reported by the authors.

Author contributions

All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

Non-standard abbreviations

eAG: estimated average glucose, HOMA-IR: Homeostatic Model Assessment of Insulin Resistance