African Americans Carry Higher Risk of Stent Thrombosis

Findings from a study published in Circulation indicate that African Americans are at in increased risk of developing stent thrombosis (ST) after drug-eluting stent implantation, even after outcomes were adjusted for socioeconomic factors and comorbidities.

While previous data has suggested that African American race predicts ST after drug-eluting stent implantation, it had not been determined whether socioeconomic status or comorbid conditions confound the contribution of race to the development of ST. With that in mind, Ron Waksman, MD, of Washington Hospital Center, and colleagues compared 1,594 black patients who underwent drug-eluting stent implantation with 5,642 non-black patients.

The researchers identified 108 definite STs, and performed multivariable Cox regression analysis with adjustment for comorbidities, including median household income as a marker of socioeconomic status, to assess the impact that black race may have on the development of ST. They found that black patients were younger and more likely to have a history of hypertension, diabetes mellitus, chronic renal insufficiency, and congestive heart failure than their counterparts. Additionally, clopidogrel compliance at the time of the ST event was higher in the black than in the nonblack population (87.5% vs. 77.8%.

Waksman and colleagues determined that “black race emerged as a strong predictor of definite late ST,” even after adjusting for median income and clopidogrel compliance; therefore, it is an independent predictor of definite drug-eluting stent ST. “Because clopidogrel compliance was higher in black patients and socioeconomic status was not associated with ST, further investigation into the potential mechanisms of this influence of race on ST must be pursued,” they concluded.

For more information:

• medGadget.com: Abbott XIENCE V Drug Eluting Stent Outperforms Boston Scientific's TAXUS Express2 in Trial
• American Heart Journal: The Effect of Intended Duration of Clopidogrel Use on Early and Late Mortality and Major Adverse Cardiac Events in Patients with Drug-eluting Stents
• American Journal of Cardiology: Racial Disparities in Outcomes Following Percutaneous Coronary Intervention with Drug-Eluting Stents