C-reactive protein, interleukin 6, fibrinogen and risk of sudden death in European middle-aged men: the PRIME study.

Objective: To examine prospectively the association of high-sensitivity C-reactive protein, interleukin 6, and fibrinogen with sudden death in asymptomatic European men.
Methods and Results: Among the 9771 men from the Etude PRospective de l'Infarctus du Myocarde (PRIME) Study, 664 had a first coronary heart disease over 10 years, including 50 sudden deaths, 34 nonsudden coronary deaths, and 580 nonfatal coronary heart disease events. For each outcome, 2 matched controls, who were free of coronary heart disease at the index date, were randomly selected from the initial cohort (nested case control study design). There was a 3-fold increased risk (95% CI, 1.20 to 7.81) of sudden death between the upper and the lower third of interleukin 6 after adjustment for baseline confounders in conditional logistic regression analysis. Neither high-sensitivity C-reactive protein (hazard ratio(third versus first tertile)=1.27; 95% CI, 0.51 to 3.17) nor fibrinogen (hazard ratio(third versus first tertile)=1.90; 95% CI, 0.76 to 4.75) was associated with sudden death. For comparison, there was a 6-fold increased risk of nonsudden coronary death from the highest compared with the lowest tertile of fibrinogen and a trend toward an association with higher C-reactive protein and higher interleukin 6. All 3 inflammatory biomarkers were moderately, but significantly, associated with nonfatal coronary heart disease.
Conclusions: Interleukin 6, but not high-sensitivity C-reactive protein or fibrinogen, is an independent predictor of sudden death in asymptomatic European men.