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.

AIMS

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).

METHODS

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.

RESULTS

More females than males with T2DM had non-fatal CHD (11.3% versus 10.6%, P < .0001). Females had slightly higher risk of non-fatal CHD since 5-10 years of diabetic duration and the effect size became larger since 15 years and onwards. Overall effect of females versus males for non-fatal CHD was 1.04 (95% CI: 1.01-1.08) among patients with <15 years of duration while the effect size increased to 1.17 (95% CI: 1.07-1.28) among patients with ≥15 years of duration. Using males with <15 years of duration as the reference, females with ≥15 years of duration were at 1.82-fold (95% CI: 1.70-1.95) non-fatal CHD risk while males with ≥15 years of duration were only at 1.56 (95% CI: 1.45-1.68) fold non-fatal CHD risk, with significant additive interaction (all three measures < 0.05).

CONCLUSIONS

Long exposure to T2DM imparted a larger risk of non-fatal CHD to Chinese females than to Chinese males.