Platelet Indices and Their Association with Vascular Complications in Type 2 Diabetes Mellitus: An Observational Study

Abstract

Background: Type 2 diabetes mellitus (T2DM) is associated with endothelial dysfunction, platelet hyperreactivity and progressive microvascular and macrovascular disease. Mean platelet volume (MPV), platelet distribution width (PDW) and platelet-large cell ratio (P-LCR) are routinely available hematological parameters that may reflect platelet size and activation. The present study evaluated platelet indices in adults with T2DM and examined their association with vascular complications. Methods: This observational study was conducted at Government Villupuram Medical College and Hospital over one year from April 2020 to March 2021. Three hundred adults with known or newly diagnosed T2DM were enrolled by convenient non-probability sampling. Patients with hematological or liver disorders, hypertension, thyroid disorders, pregnancy, recent blood transfusion and antiplatelet-drug use were excluded. A standardized clinical proforma was used to document diabetes duration and vascular complications. MPV, PDW, P-LCR and platelet count were obtained from an automated complete blood count using a Sysmex XP-100 analyzer. Glycemic measurements were performed using a Beckman Coulter biochemistry analyzer. Retinopathy, nephropathy, neuropathy, coronary artery disease (CAD), peripheral vascular disease (PVD) and cerebrovascular accident (CVA) were assessed using clinical examination and appropriate investigations. Data were analyzed using SPSS version 17; Student's t test was used for between-group comparisons and one-way ANOVA for comparisons across multiple groups. A p value <0.05 was considered statistically significant. Results: The study population had a mean age of 57.93±14.92 years; 166 (55.33%) were men and 134 (44.67%) were women. Vascular complications were documented in 139 (46.33%) participants. The mean MPV was significantly higher among participants with vascular complications than among those without complications (11.129±0.733 vs 9.924±1.168 fL; p<0.001). Mean PDW was also significantly higher (14.759±2.033 vs 13.830±2.295 fL; p<0.001). P-LCR did not differ significantly (25.252±6.013% vs 24.366±5.478%; p=0.183), and platelet count showed no significant difference in the source analysis (2.60±0.85 vs 2.77±0.97; p=0.207). The most frequent recorded complications were diabetic retinopathy (27.33%), nephropathy (19.33%), CAD (18.00%), neuropathy (11.33%), PVD (4.00%) and CVA (2.00%). Post-prandial blood glucose was higher in participants with complications than in those without complications (352.101±60.961 vs 196.516±30.042 mg/dL; p<0.001). Conclusion: In this cohort of adults with T2DM, higher MPV and PDW were associated with the presence of vascular complications, whereas P-LCR and platelet count were not significantly associated with the overall complication status. MPV and PDW may therefore serve as inexpensive, readily available markers of altered platelet phenotype in T2DM. Their clinical value as predictive biomarkers requires confirmation in larger, prospective studies with standardized definitions and multivariable adjustment. Keywords: Type 2 diabetes mellitus; platelet indices; mean platelet volume; platelet distribution width; platelet-large cell ratio; vascular complications; diabetic retinopathy; diabetic nephropathy; coronary artery diseasE