Association between insulin dosage and insulin usage time, and coronary artery lesions in patients with type 2 diabetes and coronary heart disease

Insulin is used in the treatment of type 2 diabetes, with its usage reaching 30–50% in Western countries. The aim of the present study was to determine the association between insulin dosage (ID)/insulin usage time (IT) and coronary artery lesions in patients of type 2 diabetes with coronary heart disease. Based on the insulin using dosage, 353 type 2 diabetes patients were divided into the high-dose (≥0.5 IU/kg) and low-dose (<0.5 IU/kg) group. Selected coronary angiography was performed and the Gensini score was used to determine the degree of the coronary artery lesions. The homeostasis model assessment-insulin sensitivity (HOMA-IS) index was assessed by HOMA2. Data including age, gender, smoking, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), triglyceride (TG), glucose (Glu), hemoglobin A1c (HbA1c), C-peptide, ID, IT, diabetes duration time (DT), and IT/DT were collected. The association between insulin usage (both dose and time) and the coronary artery lesions in these patients was then determined. Statistical differences for the two groups for factors including C-peptide, HbA1c, ID, IT, DT, IT/DT and the Gensini score values (P<0.05) were identified. By contrast, no significant differences for factors such as gender, smoking history, age, BMI, TC, TG, LDL, HDL, fasting insulin, Glu, SBP and DBP were observed. The coronary artery damage Gensini score in insulin-insensitive individuals was significantly greater than that in the insulin-sensitive individuals. The Spearman analysis revealed that ID and IT, DT and IT/DT were positively correlated with the coronary artery damage Gensini score. The multivariate regression, the interquartile range method and receiver operating characteristic analyses showed that ID, ID/DT, IT had a greater effect on coronary vascular damage compared with DT. In conclusion, the degree of coronary artery lesions were correlated with ID, IT, DT, IT/DT. High doses of insulin or a high IT/DT ratio may aggravate coronary artery damage.