Insulin clearance may be vascular damage indicator

Among people at risk of type 2 diabetes mellitus (T2DM), lowered insulin clearance may be an early indicator of vascular damage independently of other classical cardiovascular disease (CVD) risk factors, a recent study reports.

A total of 667 volunteers (mean age, 44.1 years; 417 women) participated in the study, all of whom were free of CVDs, but were deemed to be at risk of T2DM based on family or medical history, or body mass index. The carotid intima-media thickness (cIMT) was measured using a high-resolution ultrasound, while frequently sampled 75-g oral-glucose tolerance test (oGTT) was employed for insulin clearance analysis.

Forward stepwise regression modelling found that glucose-stimulated insulin clearance was a strong correlate of cIMT (p<0.0001), second only to age and performing better than even the traditional CVD risk factors, such as body mass index and systolic blood pressure. This analysis also identified sex and fasting insulin clearance as significant indicators of cIMT.

In subsequent multiple linear regression analysis, glucose-stimulated insulin clearance remained significantly associated with cIMT (β, –0.16; p<0.0001) even after controlling for CVD risk factors. Age, sex, body mass index, and systolic blood pressure remained significantly predictive, too.

“We identified glucose-stimulated insulin clearance as a robust parameter that was associated with higher cIMT, independent of other investigated factors,” the researchers said.

“Our results substantially add to the recent observation of a link between insulin clearance and cardiovascular risk as we systematically examined its relative contribution independent of a large number of potential risk factors for subclinical atherosclerosis that had not been tested in this regard before,” they added.