The electrocardiographic parameters QTc interval and HR at rest were negatively correlated with sirtuin 1 in the T1DM – HD group (R = –0.435, p = 0.043 and R = –0.506, p = 0.016, respectively); in the control group, the QTc interval was significantly positively associated with sirtuin 1 (R = 0.510, p = 0.004). This evidence concerns the gene SIRT1 and type 1 diabetes mellitus.