Objective: Lipoprotein-associated phospholipase A2 (Lp-PLA2) is a useful inflammatory marker of cardiovascular risk, yet little is known of its prognostic role in heart failure (HF). We evaluated the association of Lp-PLA2 with mortality in subjects with HF and assessed its incremental value for risk discrimination over established risk factors and biomarkers.
Methods: Residents of Olmsted County, MN, diagnosed with HF between September 2003 and April 2007 (n=646, mean age 76 years, 51% women) were prospectively enrolled and followed-up. Plasma Lp-PLA2 levels were measured at baseline and evaluated along with known risk indicators.
Results: Lp-PLA2 was positively associated with male gender and low-density lipoprotein cholesterol and inversely associated with statin use and diabetes. During follow-up (median 21 months), 213 deaths occurred. Elevated Lp-PLA2 was associated with an increased risk of mortality (hazard ratio (HR)=1.57; 95% confidence interval (CI): 1.03-2.37; P=0.035, per 1-unit increase in the log-transformed values). The relationship differed markedly by age (P(interaction)=0.003), with a strong association in patients under 80 years (covariate-adjusted HR=3.83; 95% CI: 1.93-7.61; P<0.001) and none in older ones (covariate-adjusted HR=0.82; 95% CI: 0.44-1.51; P=0.55). For the younger subjects, an improvement in the model's discriminatory power was obtained by adding Lp-PLA2 to established risk indicators and biomarkers (area under the receiver operating characteristic curve, 0.709-0.744, P(difference)=0.008).
Conclusion: In this community-based cohort of patients with HF, Lp-PLA2 was strongly and independently associated with mortality and contributed incrementally to risk discrimination in patients under 80 years of age.