The factors were assessed for their association with resistance to clopidogrel, including hemoglobin, hematocrit, β-blocker use, and other factors, such as comorbidities (diabetes, dyslipidemia, hypertension and previous stroke) and medications (calcium channel blockers, angiotensin receptor blockers, angiotensin-converting enzyme inhibitors, statins and diuretics). The gene discussed is ACE; the disease is diabetes mellitus.