Strong independent correlation of proteinuria with cerebral microbleeds in patients with stroke and transient ischemic attack.

OBJECTIVE To assess the association of proteinuria with the frequency and number of cerebral microbleeds (CMB), a harbinger of future hemorrhagic stroke. DESIGN Cross-sectional analysis. Patients Patients with consecutive ischemic stroke and transient ischemic attack admitted to a university hospital during a 22-month period. INTERVENTIONS Presence and number of CMB were evaluated using gradient-echo T2*-weighted magnetic resonance imaging. Multivariable models were generated to determine the contribution of proteinuria to the frequency and number of CMB after adjusting for confounders. RESULTS Of 236 patients (mean age, 70 years; 53% female), 72 (31%) had CMB present on gradient-echo imaging and 89 (38%) had evidence of proteinuria. In multivariable analyses with presence of CMB as the outcome, higher urinary protein (odds ratio [OR], 2.33; 95% confidence interval [CI], 1.10-4.95), being female (OR, 2.29; 95% CI, 1.19-4.49), history of atrial fibrillation (OR, 2.49; 95% CI, 1.14-5.44), elevated serum homocysteine (OR, 1.19; 95% CI, 1.09-1.29), and small-vessel disease subtype (OR, 2.95 95% CI, 1.43-6.10) were all significantly associated with presence of CMB. Logistic regression analysis by number of CMB showed similar findings. CONCLUSIONS Proteinuria is strongly associated with both the frequency and number of CMB in patients with recent cerebral ischemia. Urinary protein excretion may be a CMB risk marker or potential therapeutic target for mitigating the untoward clinical sequela of CMB.