Background: Chronic kidney disease is a risk factor for death in the year following myocardial infarction or coronary angioplasty. Whether the risk is similar after coronary stenting, whether impaired renal function is associated with an increased risk of cardiovascular death or myocardial infarction (MI) after coronary stenting and whether this risk is maintained beyond the first year are uncertain.
Methods: We analyzed the long-term risks of MI or the combination of cardiovascular death and non-fatal MI in patients participating in 4 coronary stenting trials with mandated, prospective long-term follow-up. Cox proportional hazards models were used to adjust for confounding and to generate multivariable odds ratios.
Results: Patients (n=1,228) were followed for a median of 5 years. There were 125 MIs and 55 cardiovascular deaths. Patients with a serum creatinine>or=1.3 mg/dL had markedly elevated risks of cardiovascular death and MI that emerged during the first year and were maintained throughout follow-up. The adjusted hazard ratio of MI was 2.14 (p=0.006) while the adjusted hazard ratio of a combined end point of MI or cardiovascular death was 2.13 (p=0.001). The risks were similar in patients with moderate (serum creatinine 1.3-1.9 mg/dL) or advanced chronic kidney disease.
Conclusions: The presence of even mild chronic kidney disease is associated with a high risk of cardiovascular death and MI following coronary stenting. Further research to address the causes of the association and to define the best therapy for these patients is necessary.