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. MethodsResultsA 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. 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) mol/l vs 9.7 (8.8-10.9) mol/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) mm(3) vs 61.1 (7.6-239.9) mm(3)] and absolute calcified plaque volume [33.5 (8.3-148.3) mm(3) vs 4.7 (0.9-17.3) mm(3)] 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]. ConclusionsWhat's new?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. It is known that Type 2 diabetes increases the risk of developing coronary artery disease more markedly in women than in men, but differences in coronary plaque composition between the sexes are poorly elucidated. This study found that women have smaller absolute volumes of coronary plaque components but a more unfavourable coronary plaque structure and enhanced systemic inflammation. The reported difference in plaque composition between men and women with a new diagnosis of Type 2 diabetes might be the basis for larger studies evaluating the impact of sex-differentiated therapeutic strategies at an early stage of Type 2 diabetes to prevent the development and progression of cardiovascular disease.