Understanding the controversy surrounding the correlation between fibrinogen level and prognosis of coronary artery disease-The role of the subtypes of coronary artery disease.

BACKGROUND: There is a controversy surrounding the correlation between fibrinogen (Fib) level and prognosis of coronary artery disease (CAD). We try to investigate the role of the subtypes of CAD in this controversy.

METHODS: A retrospective analysis was conducted from a single center CAD registered database. 3020 consecutive patients with CAD confirmed by coronary angiography were enrolled. The end points were all-cause mortality.

RESULTS: The mean follow-up time was 27.2±13.1months and death events occurred in 258 cases. Mortality rates for patients with CAD and those in the stable coronary artery disease (SCAD) and unstable angina pectoris (UAP) groups exhibited an overall rising trend as Fib levels increased (log rank test, all p<0.05). However, similar trends were not detected in patients with acute myocardial infarction (AMI). The results of a Cox proportional-hazards regression analysis showed that Fib level was independently correlated with the risk of death in patients with CAD as well as those in the SCAD and UAP groups (CAD, HR 1.40, CI 1.16-1.68; SCAD, HR 1.86, CI 1.24-2.79; UAP, HR 1.42, CI 1.06-1.90). In the AMI group, however, no independent correlation was observed between Fib level and mortality.

CONCLUSION: The different proportions of subtypes of CAD affected the correlation between Fib level and the clinical prognosis of patients with CAD. This is maybe a clue to explain the controversy.