The platelet to lymphocyte ratio (PLR) may aide in stratifying risk in coronary artery disease (CAD), according to the results of a meta-analysis published in Angiology.
Publication databases were searched through October 2019 for studies in the relationship between PLR and CAD was examined. A total of 14 studies (n=4871) were included in the final analysis, of which 11 were cohort studies, 2 were case-control studies, and 1 was a cross-sectional study. The analyses investigated the relationship between PLR and stable CAD (n=8), PLR and coronary slow flow (CSF; n=4), PLR and stable CAD by severity (n=3), and PLR and coronary collateral circulation (CCC; n=2). The studies were conducted in Turkey (n=11), China (n=1), Egypt (n=1), and India (n=1).
Patients with stable CAD had a higher PLR compared with control individuals (weighted mean difference [MD], 21.71; 95% CI, 10.16-33.26; P =.002), and patients with atherosclerosis had higher PLR than control individuals (MD, 32.39; 95% CI, 20.74-44.05; P <.001). PLR increased with the severity of atherosclerosis (MD, 26.76; 95% CI, 23.73-29.79; P <.001).
Patients with poor vs good CCC had higher PLR (MD, -24.32; 95% CI, -28.28 to -20.37; P <.001), and those with CSF had higher PLR compared with individuals with normal coronary flow (MD, 49.01; 95% CI, 11.10-86.92; P =.01).
Study limitations include the high levels of heterogeneity between studies examining the relationship between PLR and stable CAD, atherosclerosis, and CSF.
“Platelet to lymphocyte ratio, as a simple, cost-effective biomarker, may be useful for stratification of high-risk patients with stable CAD,” concluded the study authors.
Qiu Z, Jiang Y, Jiang X, et al. Relationship between platelet to lymphocyte ratio and stable coronary artery disease: Meta-analysis of observational studies. Angiology. 20202;3319720943810. doi:10.1177/0003319720943810