Insulin resistance probability score and incident cardiovascular disease

Background: Insulin resistance (IR) is associated with cardiovascular disease (CVD). However, insulin immunoassay variability and scarce research of the elderly have hindered the adoption of IR assessment for CVD prevention. We asked whether the probability of having IR [p(IR)]—derived from insulin and C-peptide mass-spectrometry assays—was associated with CVD in the elderly. Methods: A random cohort was drawn from MPP, a population-based study of the elderly. After excluding those with missing data, CVD, or diabetes, 3645 participants (median age = 68) remained. Results: During follow-up (13.3 years), 794 incident CVD events were observed. p(IR) > 80% (n = 152) compared with p(IR) ≤ 80% was associated with incident CVD (HR = 1.51, 95% CI 1.12–2.05, p = 0.007) and CVD or all-cause mortality (HR = 1.43, 95% CI 1.16–1.77, p = 0.0009) after adjusting for age, sex, hypertension, smoking, HDL-cholesterol, total cholesterol, triglycerides, BMI, and prediabetes. Conclusion: High p(IR) was associated with >50% greater risk of incident CVD. IR assessment in the elderly may be warranted.