The age-specific prognostic impact of the platelet-to-lymphocyte ratio on long-term outcome after acute coronary syndrome

Abstract

Abstract Background Personalized risk stratification within the ageing society after ACS remains scarce. With increasing general life expectancy, easily applicable age-specific strategies for the prediction of fatal adverse events are in urgent need. Increased platelet activity together with inflammatory activation play a key role during ACS. Objective We aimed to evaluate the age-specific prognostic potential of the platelet to lymphocyte ratio (PLR) on long-term cardiovascular mortality after ACS. Methods Patients presenting with ACS admitted to a tertiary care centre with a high-volume cardiac catheterization unit between December 1996 and January 2010 were recruited within a clinical registry including assessment of peripheral blood samples. The impact of the PLR on survival was assessed by Cox-regression hazard analysis. Results We included a total of 681 patients with a median age of 64 years (IQR:45–84). 200 (29.4%) individuals died during the median follow-up time of 8.5 years. A strong and independent association of the PLR with cardiovascular mortality was found in the total study population (adjusted [adj.] hazard ratio [HR] per one standard deviation [1-SD] of 1.52 [95% CI: 1.18–1.96; p<0.001). After stratification in individuals <65 years (n=339) and ≥65 years (n=342), a prognostic effect of the PLR on cardiovascular mortality was solely observed in elderly patients ≥65 years (adj. HR per 1-SD of 1.32 [95% CI: 1.01–1.74]; p=0.045), but not in their younger counterparts <65 years (adj. HR per 1-SD of 1.08 [95% CI: 0.60–1.93]; p=0.804). Conclusion The present investigation highlights a strong and independent age-specific association of the PLR with cardiovascular mortality in patients with ACS. The PLR only allows to identify patients ≥65 years at high risk for fatal events after ACS – even from a long-term perspective. Funding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): Medical University of Vienna Effect of PLR stratified by age