Lipid transfer protein activities in type 1 diabetic patients without renal failure and nondiabetic control subjects and their association with coronary artery calcification

This study examined the role of cholesteryl ester transfer (CET), cholester yl ester transfer protein (CETP) activity, and phospholipid transfer protei n (PLTP) activity in the increased prevalence of coronary artery calcificat ion (CAC) in diabetic subjects compared with nondiabetic subjects and in th e loss of the sex difference in CAC in diabetes. CETP activity, PLTP activi ty, and CET were measured in 195 type 1 diabetic subjects without renal fai lure and 194 nondiabetic control subjects of similar age (30-55 years) and sex distribution (50% female). CAC was quantified with electron beam comput ed tomography. CETP activity was higher in diabetic subjects (mean 84 arbit rary units [AU]) than in nondiabetic subjects (80 AU, P = 0.028). PLTP acti vity was also higher in diabetic subjects (96 AU) than in nondiabetic subje cts (81 AU, P < 0.001). However, CET was lower in diabetic men (geometric m ean 32 nmol ml(-1) . h(-1)) than nondiabetic men (37 nmol . ml(-1) . h(-1), P = 0.004) and did not differ between diabetic (30 nmol ml(-1) . h(-1)) an d nondiabetic (32 nmol . ml(-1) . h(-1), P = 0.3) women. CETP and PLTP acti vities were not associated with CAC. CET was positively associated with CAC in both diabetic and nondiabetic subjects (odds ratio per 10 nmol . ml(-1) . h(-1) increase in CET in all subjects = 1.4, P = 0.001). The prevalence of CAC was similar in diabetic (51%) and nondiabetic (54%, P = 0.7) men but was much higher in diabetic (47%) than nondiabetic (21%, odds ratio 3.6, P < 0.001) women so that there was no sex difference in CAC in diabetic subj ects. The odds of CAC in diabetic women compared with nondiabetic women was altered little by adjustment for CETP activity, PLTP activity, or CET (odd s ratio on adjustment 3.7, P < 0.001). The greater effect of diabetes on CA C in women than in men, i.e., the loss of the sex difference in CAC, was in dependent of CETP and PLTP activity and GET. In conclusion, among both diab etic and nondiabetic subjects, higher cholesteryl ester transfer is a risk factor for CAC. However, abnormalities in cholesteryl ester transfer or lip id transfer protein activities do not underlie the increased CAC risk in di abetic women compared with nondiabetic women or the loss of the sex differe nce in CAC in diabetes.