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.