High-Sensitivity CRP Predicts Long-term Mortality in Patients Receiving DES

Measurement of high-sensitivity C-reactive protein (hsCRP) prior to PCI predicts cardiovascular risk out to 10 years, according to a study published online July 9, 2015, ahead of print in EuroIntervention. 

The results “confirm that hsCRP may be a useful biomarker to assess the risk of death and [MI] in patients with established [CAD] who undergo PCI,” say Ron T. van Domburg, PhD, of Erasmus University Medical Center (Rotterdam, the Netherlands), and colleagues. 

The investigators measured circulating hsCRP levels immediately before PCI in a subset of 468 patients (mean age 61 years; 69% men) who received the Cypher sirolimus-eluting stent (Johnson & Johnson/Cordis) between April and October 2002 while enrolled in the single-center, all-comers RESEARCH registry. 

hsCRP levels were classified as low (< 1 mg/L), intermediate (1-3 mg/L), or high (> 3 mg/L). 

The presence of diabetes, a history of MI, and smoking correlated with higher hsCRP levels. While women tended to have higher levels than men, the difference was not statistically significant (P = .074). Patients with unstable angina had the highest hsCRP levels, followed by those with acute MI and stable angina. 

Clear Predictor

Kaplan-Meier curves showed ongoing divergence in rates of all-cause mortality or MI (primary endpoint) for the hsCRP groups throughout the 10-year period: 14.7% for low levels, 31.1% for intermediate, and 43.1% for high. 

After adjustment for established cardiovascular risk factors and clinical presentation, patients with high and intermediate baseline levels of hsCRP had more than double the risk of all-cause mortality/MI of those with low biomarker levels. They also had increased all-cause mortality (table 1).

When added to a predictive model incorporating conventional cardiovascular risk factors, hsCRP only slightly improved its discriminatory ability for 10-year cardiovascular outcome (P = .56). However, it did result in better classification of the predicted risk of death or MI during follow-up (P < .001). 

Useful Tool in Clinical Practice

According to the authors, few studies have looked at the prognostic value of hsCRP over such a long time frame, with the lengthiest reports extending to 6 years in ACS patients. The 10-year follow-up in the current study is “of particular interest in clinical practice,” they say. 

Dr. van Domburg and colleagues suggest 2 possible mechanisms to explain the prognostic value of hsCRP in this context. 

“Firstly, high CRP levels have previously been shown to be associated with stent thrombosis and restenosis after PCI with first-generation [DES],” they note, adding that there is growing evidence regarding late adverse reactions to the devices. 

While less evidence is available for second-generation DES, at least 1 study has shown that elevated CRP is an independent predictor of neointimal hyperplasia in patients receiving zotarolimus-eluting stents. Another possible mechanism may be the association of high CRP levels with coronary plaque burden and new events in native vessels, they add.   

The researchers conclude that hsCRP “may be a useful biomarker for long-term risk assessment in patients with established [CAD] and undergoing PCI.” There also may be implications for statin therapy in DES-treated patients, they add, since those “with intense activation of inflammatory cells, as detected by systemic CRP levels, are likely to enjoy the highest benefit from a high-dosed statin treatment.”

Source: 
Oemrawsingh RM, Cheng JM, Akkerhuis KM, et al. High-sensitivity C-reactive protein predicts 10-year cardiovascular outcome after percutaneous coronary intervention. Eurointervention. 2015;Epub ahead of print. 

Disclosure:

• Dr. van Domburg reports no relevant conflicts of interest. 

Related Stories:

• PROSPECT Substudy: Persistently High CRP Predicts Future MACE in ACS Patients After PCI
• Elevated CRP—But Not High Platelet Reactivity—Predictive After DES
• Elevated CRP Predicts Stent Thrombosis, Death, MI in DES Patients