Mean platelet volume and its relation to insulin resistance in non-diabetic patients with slow coronary flow

SummaryBackgroundIncreased mean platelet volume is a central process in the pathophysiology of coronary heart disease. Insulin resistance contributes to increased platelet activation.AimTo assess the mean platelet volume and its possible relationship with insulin resistance in non-diabetic patients with slow coronary flow.Methods and subjectsThe study included 60 patients with slow coronary flow and 20 subjects (controls) with normal coronary arteries. Slow coronary flow patients were divided into 2 groups, insulin resistant (32 patients) and insulin sensitive (28 patients) according to the homeostasis model assessment of insulin resistance index (HOMA-IR).ResultsPatients with slow coronary flow had significantly higher mean platelet volume values (7.9 ± 0.47 vs. 7.1 ± 0.5, p < 0.01), insulin level (10.8 ± 3.2 vs. 8.2 ± 1.4, p < 0.01), and HOMA-IR scores (2.72 ± 0.85 vs. 1.84 ± 0.19, p < 0.01). These parameters were significantly higher in insulin-resistant patients than in insulin-sensitive ones. The mean platelet volume was correlated with HOMA-IR (r = 0.52, p < 0.01) and insulin level (r = 0.58, p < 0.01). In multivariate analysis, mean platelet volume and HOMA-IR were independent predictors of mean TIMI frame count {(B ± SE = 0.562 ± 2.95, p < 0.01) and (B ± SE = 0.538 ± 2.46, p < 0.01), respectively}.ConclusionPatients with slow coronary flow have increased mean platelet volume which was associated with insulin resistance in non-diabetic slow coronary flow patients. TIMI frame counts correlated with mean platelet volume and increased insulin resistance. Thus, insulin resistance and platelet activity may have a role in the pathogenesis of slow coronary flow. Also, they may have a possible benefit as follow-up markers in non-diabetic patients with slow coronary flow.