HOMA-IR (Homeostatic Model Assessment for Insulin Resistance)

Why Use

Clamp methods for measuring IR are resource intensive, invasive, and time consuming, and IR can be a useful metric. An estimate of IR may help decision making.

When to Use

Patients evaluated for potentially impaired glucose tolerance and diabetes.

Formula

Pearls / Pitfalls

The score, a shortcut for estimating insulin resistance (IR), has been examined in multiple studies. Results typically show reasonable correlation between HOMA-IR and ‘clamp’ measurement, the gold standard. However, agreement levels between the two, a more important gauge for individual accuracy and clinical use, are weak, suggesting more research and refinement are needed for clinical use.

Management

We are unaware of validated management algorithms using the HOMA-IR score.

Critical Actions

The HOMA-IR score should not be used in patients on insulin, and studies have questioned its accuracy in those with impaired glucose tolerance, normal BMI, the elderly, and others.

Advice

The HOMA-IR score may be most useful for epidemiologic, population-based, and other group level assessments. In addition, optimal diagnostic cutoffs for IR-related conditions seem to vary considerably from one population or group to the next, so care should be taken to customize cutoffs when using the score.

More Information

The HOMA-IR is used to measure severity of insulin resistance, though normal insulin resistance varies depending on the population. Common reference levels for HOMA-IR insulin resistance range from 0.7 - 2.