Sex differences in coronary plaque composition evaluated by coronary computed tomography angiography in newly diagnosed Type 2 diabetes: association with low-grade inflammation.

AIM: To determine differences in coronary plaque composition and inflammatory biomarkers between men and women with newly diagnosed Type 2 diabetes without known cardiovascular disease.

METHODS: A total of 88 people with newly diagnosed (<1 year) Type 2 diabetes underwent contrast-enhanced coronary computed tomography angiography. Advanced coronary plaque analysis was performed using semi-automated software. Plasma concentrations of inflammatory biomarkers were determined.

RESULTS: There were no significant differences between men (n=60) and women (n=28) regarding age or cardiovascular risk factors (all P>0.05). The median (quartiles) serum levels of fibrinogen [10.9 (9.8-12.6) μmol/l vs 9.7 (8.8-10.9) μmol/l], fibrin d-dimer [0.3 (0.2-0.4) mg/l vs 0.27 (0.2-0.4) mg/l] and C-reactive protein [3.1 (1.1-5.2) mg/l vs (0.8-2.6) 1.6 mg/l] were significantly higher in women (all P<0.05). Overall, men more often had multi-vessel involvement [28 men (47%) vs 4 women (14%)], and higher total plaque burden [median (quartiles) 11.6 (2.3-36.0)% vs 2.0 (0.4-5.4)%; both P<0.05]. The median (quartiles) total plaque volume [269.9 (62.6-641.9) mm3 vs 61.1 (7.6-239.9) mm3 ] and absolute calcified plaque volume [33.5 (8.3-148.3) mm3 vs 4.7 (0.9-17.3) mm3 ] were higher in men (both P<0.05). Women had a lower relative proportion of the calcified plaque component [median (quartiles) 7.8 (4.7-15.4)% vs 23.7 (8.4-31.1)%] and a higher relative proportion (median [quartiles]) of the non-low-density non-calfied plaque component [77.6 (66.0-86.0)% vs 63.6 (54.0-72.9)%; both P<0.05].

CONCLUSIONS: In people with newly diagnosed Type 2 diabetes, women had lower absolute coronary plaque volumes but a more unfavourable plaque composition and enhanced systemic inflammation compared with men.