PLATELET-TO-LYMPHOCYTE RATIO AS A PREDICTOR OF CARDIOVASCULAR RISK IN TYPE 2 DIABETES MELLITUS

Abstract

Background: Cardiovascular disease is a major cause of morbidity and mortality in type 2 diabetes mellitus (T2DM). Chronic inflammation, endothelial dysfunction, and platelet activation contribute to accelerated atherosclerosis. The platelet-to-lymphocyte ratio (PLR), derived from a routine complete blood count, may provide a simple marker of cardiovascular-risk burden. Objective: To evaluate the association between PLR and estimated 10-year cardiovascular risk among adults with T2DM and to assess the ability of PLR to identify patients with higher cardiovascular risk. Materials and Methods: This multicentre cross-sectional analytical study was conducted in the Departments of General Medicine at Geetanjali Institute of Medical Sciences, Jaipur, and Mahatma Gandhi Medical College and Hospital, Jaipur, from 1 July 2025 to 1 July 2026. A total of 200 adults aged 40–74 years with T2DM and without established cardiovascular disease were included. PLR was calculated from the platelet count and absolute lymphocyte count obtained from the same complete blood-count sample. Ten-year cardiovascular risk was estimated using the 2019 World Health Organization laboratory-based cardiovascular disease risk charts for the South Asia region. One-way analysis of variance, Spearman correlation, multivariable logistic regression, and receiver operating characteristic analyses were performed. Results: The mean age of the 200 participants was 56.5 ± 8.1 years; 119 (59.5%) were men. Mean PLR was 128.8 ± 32.9. PLR increased from 106.7 ± 28.6 in the <5% cardiovascular-risk category to 156.9 ± 30.9 in the ≥30% category (one-way ANOVA F(4,195)=17.19, p<0.001). PLR correlated positively with estimated 10-year cardiovascular risk (Spearman ρ=0.511, p<0.001). Fifty-one participants (25.5%) had an estimated risk ≥20%. PLR identified this higher-risk group with an area under the ROC curve of 0.778 (95% CI 0.702–0.844); the optimal cutoff was 134.5, with sensitivity of 78.4% and specificity of 68.5%. Each 10-unit increase in PLR was associated with higher odds of estimated risk ≥20% after adjustment for HbA1c, BMI, and eGFR (adjusted OR 1.39, 95% CI 1.19–1.62, p<0.001). Conclusion: PLR showed a graded association with increasing estimated 10-year cardiovascular risk in patients with T2DM and demonstrated moderate discriminatory ability for identifying participants with risk ≥20%. PLR may be useful as an inexpensive adjunct to conventional cardiovascular-risk assessment, but prospective studies using incident cardiovascular events are required before it can be used as a stand-alone prediction marker.