Proteinuria Predicts Resistance to Antiplatelet Therapy in Ischemic Stroke

The occurrence of a stroke while on antiplatelet agents presents a therapeutic dilemma. One of the main causes for recurrent strokes is antiplatelet resistance more commonly known as high on treatment platelet reactivity (HTPR). Prior studies have established that proteinuria is associated with HTPR following myocardial infarction. Here, we investigated whether dipstick proteinuria correlates with HTPR in patients presenting with stroke. We performed a retrospective cohort analysis of 102 patients admitted for a recurrent ischemic stroke that had either a VerifyNow aspirin or VerifyNow clopidogrel laboratory test performed to assess platelet reactivity. Dipstick proteinuria was defined as > 30 mg/dl (2+ or more). HTPR was defined as an aspirin resistance unit > 550 for aspirin and a P2Y12 reactivity unit > 208 for clopidogrel. Patients with proteinuria on dipstick were significantly more likely to have HTPR to either aspirin (p value 0.017) or clopidogrel (p value 0.017). After controlling for age, smoking, diabetes, hypertension, CAD and GFR, proteinuria was an independent predictor of HTPR for patient taking aspirin (p = 0.025). Platelet resistance is an entity that undermines the activity of antiplatelet agents in reducing stroke risk. Here, we demonstrate an association with increased platelet reactivity and proteinuria. This highlights a potential new therapeutic target in reducing future stroke risk.