Association Between Platelet Parameters and Metabolic Syndrome in Residents of Wuhu, China: A Mediation Analysis of Insulin Resistance

Objective: To examine the associations between platelet parameters and metabolic syndrome (MetS) and to explore their relationships with insulin resistance (IR). Patients and Methods: This cross-sectional study included approximately 570,000 adults who underwent health examinations at the Health Management Center of the First Affiliated Hospital of Wannan Medical College between 2017 and 2023. Demographic and behavioral data were collected using questionnaires, and relevant clinical measurements were obtained through physical examinations. Platelet parameters and metabolic indicators were measured using an automated analyzer. Restricted cubic spline (RCS) models and multivariable logistic regression analyses were used to assess the associations between platelet parameters and MetS. Bootstrap-based mediation analysis was applied to explore the statistical associations among platelet parameters, IR, and MetS. Results: The prevalence of MetS was 19.5%. Platelet count (PLT), mean platelet volume (MPV), platelet distribution width (PDW), and plateletcrit (PCT) were all positively associated with MetS (all P < 0.001). After multivariable adjustment, PCT and PDW showed relatively stronger associations with MetS (PCT: Q4 vs Q1, aOR = 1.85, 95% CI: 1.81-1.89; PDW: Q4 vs Q1, aOR = 1.73, 95% CI: 1.69-1.76). Multivariable linear regression analysis showed that PDW was positively associated with IR assessed by the triglyceride-glucose index (TyG) (β = 0.150, 95% CI: 0.146-0.155). Within the analytical models of this study, PDW, IR, and MetS exhibited statistically significant associations. Conclusion: Elevated platelet parameters were positively associated with MetS, with particularly pronounced associations observed for PCT and PDW. PDW was significantly associated with IR, and IR was in turn closely associated with MetS.