Coronary spastic angina is associated with insulin resistance - possible involvement of endothelial dysfunction.

Objective: In this study, we examined whether coronary spastic angina (CSA) is associated with insulin resistance.

Background: There is increasing evidence that insulin resistance is associated with endothelial dysfunction. Patients with CSA show endothelial dysfunction.

Methods: The study participants include 111 CSA patients (81 men and 30 women, mean age 62±12 years) and 53 participants without CSA (24 men and 29 women, mean age 63±10 years), serving as the controls. The oral glucose tolerance test was performed, and anthropometric parameters, plasma glucose and insulin levels, lipid profiles, and other laboratory parameters were evaluated.

Results: Homeostasis model assessment of insulin resistance (HOMA-IR), Log HOMA-IR, the quantitative insulin sensitivity check index, the insulin sensitivity index, and insulin resistance 60-120 min after glucose load (log post-glucose-IR) were calculated as surrogate markers of insulin resistance. The number of men, the number of smokers, log post-glucose-IR, the insulin sensitivity index, and fasting plasma glucose levels were higher in CSA patients compared with controls (P=0.001, 0.001, 0.004, 0.012, and 0.013, respectively), whereas plasma high-density lipoprotein cholesterol levels were lower (P<0.001).

Conclusion: Insulin resistance on glucose load (log post-glucose-IR), plasma high-density lipoprotein cholesterol levels, and smoking were significantly associated with CSA (r=0.225, P=0.004; r=-0.313, P<0.001; and r=0.258, P=0.001, respectively).