Procalcitonin and Midregional Proatrial Natriuretic Peptide as Biomarkers of Subclinical Cerebrovascular Damage: The Northern Manhattan Study

Background and Purpose - Chronic infections and cardiac dysfunction are risk factors for stroke. We hypothesized that blood biomarkers of infection (procalcitonin) and cardiac dysfunction (midregional proatrial natriuretic peptide [MR-proANP]), previously associated with small vessel stroke and cardioembolic stroke are also associated with subclinical cerebrovascular damage, including silent brain infarcts and white matter hyperintensity volume. Methods - The NOMAS (Northern Manhattan Study) was designed to assess risk factors for incident vascular disease in a multiethnic cohort. A subsample underwent brain magnetic resonance imaging and had blood samples available for biomarker measurement (n=1178). We used logistic regression models to estimate the odds ratios and 95% confidence intervals (95% CIs) for the association of these biomarkers with silent brain infarcts after adjusting for demographic, behavioral, and medical risk factors. We used linear regression to assess associations with log-white matter hyperintensity volume. Results - Mean age was 70±9 years; 60% were women, 66% Hispanic, 17% black, and 15% were white. After adjusting for risk factors, subjects with procalcitonin or MR-proANP in the top quartile, compared with the lowest quartile were more likely to have silent brain infarcts (adjusted odds ratio for procalcitonin, 2.2; 95% CI, 1.3-3.7 and for MR-proANP, 3.3; 95% CI, 1.7-6.3) and increased white matter hyperintensity volume (adjusted mean change in log-white matter hyperintensity volume for procalcitonin, 0.29; 95% CI, 0.13-0.44 and for MR-proANP, 0.18; 95% CI, 0.004-0.36). Conclusions - Higher concentrations of procalcitonin, a marker of infection, and MR-proANP, a marker of cardiac dysfunction, are independently associated with subclinical cerebrovascular damage. If further studies demonstrate an incremental value for risk stratification, biomarker-guided primary prevention studies may lead to new approaches to prevent cerebrovascular disease.