Long exposure to type 2 diabetes and risk of non-fatal coronary heart disease in Chinese females and males: Findings from a China national cross-sectional study

•We tested gender differences in coronary heart disease (CHD) risk in type 2 diabetes (T2DM).•Long exposure to T2DM imparts a larger CHD risk to females than to males.•The excessive risk couldnot be explained by increased conventional risk factors. To investigate the risk of Chinese females versus males for non-fatal coronary heart disease (CHD) due to long exposure to type 2 diabetes mellitus (T2DM). 223,612 Chinese patients with T2DM were recruited from China in 2012. Binary logistic regression analysis was performed to obtain odds ratios (OR) of females versus males for non-fatal CHD. Additive interaction was used to test whether female gender and long exposure to T2DM (≥15 years) had a synergistic effect for non-fatal CHD. Significant relative excess risk due to interaction (RERI > 0), attributable proportion due to interaction (AP > 0) or synergy index (SI > 1) suggest a significant additive interaction. More females than males with T2DM had non-fatal CHD (11.3% versus 10.6%, P